Ulva Species Usage in Aquaculture: Current Status and Future Prospective Volume 51- Issue 4

Mohamed H Abo-Raya¹, Reda F A Abdelhameed² and Radi A Mohamed¹*

• ¹Department of Aquaculture, Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, Egypt
• ²Department of Pharmacognosy, Faculty of Pharmacy, Suez Canal University, Egypt

Received: July 05, 2023;   Published: July 24, 2023

*Corresponding author: Radi A Mohamed, Department of Aquaculture, Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, Kafrelsheikh, Egypt

DOI: 10.26717/BJSTR.2023.51.008147

Abstract PDF

Concerns about the economy, the environment, and production have sparked a search for long-acting immune-stimulants and growth promoters for aquatic species. Ulva spp. as green macro-algae is currently being studied as a potential alternative source for a variety of antibiotics and its wide range of availability and chemical composition creates both opportunities and challenges. Various studies have recently been undertaken on the utilization of Ulva spp. as a protein, lipids, carbohydrates, and vitamins source; besides, the existence of a wide range of bioactive compounds which can be used as antihypertensive, antioxidative, antitumor, antimicrobial, and anticoagulant components in functional foods or pharmaceuticals and nutraceuticals due to their health benefits and therapeutic potentials. Moreover, different researchers have used Ulva spp. in different forms, such as fresh, extract, and powder, to examine its effects on different aquatic organisms like fish, crustaceans, and molluscs. As a result, this review article aims to highlight the properties, impacts, and application methods of various Ulva spp.

Keywords: Ulva spp.; Aquatic Organisms; Feed; Effects

Seaweeds have been used for a variety of applications, including human-eating [1], paper manufacturing, cosmetics, animal feeding, wastewater treatment, medical research, and fertilizers [2-4]. Furthermore, green seaweed provide a sustainable biomass feedstock for the biotech industries and food, including bioremediation, future biofuel generation, and integrated aquaculture systems, from an economic standpoint [5,6].

Ulva is a chlorophyte, an informal collection of three traditional groups (Ulvophyceae, Trebouxiophyceae, and Chlorophyceae) [7-9]. The Trebouxiophyceae and Chlorophyceae diversified significantly in terrestrial and freshwater settings, while the Ulvophyceae dominated marine environments [10]. Furthermore, the morphological and cytological diversity of Ulvophyceae is amazing [11]. Sheet, unicells-like thalli, filaments, and giant-celled coenocytic or siphonal macro-algae [12] branch and fuse to form morphologies with root-, leaf-, and stemlike structures similar in size to large shrubs on land [13-15]. Due to eutrophication-driven tides in shallow areas, Ulva is becoming more essential in coastal ecosystem management [16,17]; besides, it has become available to do much research in the field of aquaculture; for example, U. fasciata [18], U. lactuca [19], U. rigida [20], and U. clathrata [21].

Although some studies have reported that different Ulva spp. have positive effects on different parameters such as growth and immunity, other studies have negative effects, and others have proven that there is no effect. These data varied according to fish spp., Ulva spp., concentrations used, and method of use. However, most of them dealt with Ulva as powder and few studies reported on Ulva as fresh and extract; besides, few studies documented its effects on growth, immune, and antioxidant-related gene expressions [18]. In general, the economic, academic, environmental, and biological significance of macro-algae, especially of Ulva spp. is not widely valued and discussed. As a result, this review targets to integrate the literature and delivers an essential perception of the use of different Ulva spp. in aquatic organisms’ feed. This review study achieves three (3) main purposes:

a) To describe the characteristics and chemical composition of different Ulva spp.
b) To describe the potential methods of different Ulva spp. used in different aquatic organisms’ feeds.
c) To explore the impacts of dietary supplementation of different Ulva spp. on immunological and growth parameters.

General Structure and Characteristics of Ulva spp.

Figure 1

They do not have real roots, leaves, and stems; moreover, because of its enlarged leaf-like structures that resemble garden lettuce, it’s also known as sea lettuce. Ulva’s morphology shows distinct seasonal fluctuations; for example, small plants are sensitive to the touch and dark green in colour, but older thalli turn light green and their surface becomes slimy [22]. The specific characteristics of different Ulva spp. are shown in Table 1 [23-37]. They have simple reproductive structures with no vascular tissue and form multilayered and stable vegetation that captures available photons from sunlight.

Table 1: The specific characteristics of most common Ulva spp.

Table 2: Proximal composition of different Ulva spp. reported in different studies.

Ulva chemical composition:

As shown in Table 2 [38-56]. Ulva has an intriguing chemical composition that enables them to be used in the production of functional or health-promoting foods appealing. Crude protein, ash, crude fat, and fiber contents in Ulva meals range from 1.6 to 32% percent, 2.9 to 44 percent, 0.1 to 6 percent, and 0.6 to 40%, respectively.

The chemical composition of Ulva varies based on species, geographical distribution, physiological status, and other factors, such as the primary environmental determinants like salinity, water temperature, nutrients, light, and minerals availability [57]. In general, macro- algae is rich in vitamins, minerals, and non-starch polysaccharides [58].

Because of their mineral richness or the useful qualities of their polysaccharides, seaweed is typically employed in human or animal food. However, the importance of seaweed proteins for nutrition is rarely emphasized [59]. Species and seasons have an impact on the protein content of seaweed. Ulva’s amino acid profile has been the subject of in-depth research. Aspartic and glutamic acids make up a sizable portion of the amino acid composition in many organisms. Between 26 to 32 percent of the total amino acids are found in green seaweed [60]. Red and brown seaweeds are additionally higher potential sources of DHA and EPA than green seaweeds due to changes in colour and fatty acid contents [60].

Cultivation of Ulva spp.:

Ulva cultivation and harvesting are quite simple and, due to its size compared to micro-algae, a substantial amount of biomass can be collected [61]. Three basic sources of macro-algal biomass for downstream processing are used:

a) harvesting seaweed directly from the sea,
b) collecting dead macro-algae from the coast, and
c) cultivating selected seaweed species [62]. Direct cultivation
of Ulva is possible in open water. Onshore, offshore, and integrated seaweed cultivation are some of the different techniques for growing seaweed [62].

The macro-algal growth life cycle depends on different factors, such as nutrients availability and photosynthesis; besides, various environmental parameters such as water salinity, temperature, current, and depth [63].

Harvesting of Ulva:

There is a lengthy history of macro-algae harvesting in many coastal regions [64]. The two types techniques of harvesting are:
a) Mechanical (moving boat, dredge, and mesh conveyor)
b) Manual (hand)
Harvesting takes place three times a year on average in natural water bodies. However, intense mechanical harvesting has negative repercussions for marine ecosystems and significantly reduces macro- algae development [65]. Moreover, harvesting macro-algae blooms has not proven to be economically viable in the world [66]. However, in some other areas, the elimination of proliferating macro-algae development as a means of eliminating surplus nutrients from the environment is advantageous.

Integrating Ulva with Mariculture:

Mariculture refers to the practice of raising aquatic organisms in regulated or semi-controlled environments [67]. Ulva spp., a type of seaweed, has a variety of applications and is gaining popularity as a new experimental system for biological research, as well as a component of integrated aquaculture systems [68].

Different Methods of Ulva spp. Application

As illustrated in Figure 2, Ulva can be added through different methods.

Figure 2

Table 3: Studies on the use of Ulva as a fresh in crustaceans feed.

Table 4: Studies on the use of Ulva as a fresh in molluscs feed.

Ulva Addition as Fresh:

As illustrated in Table 3 [69-74] and Table 4 [75-80], different Ulva species can be added fresh to the diets of crustaceans and molluscs, but they are never used in fish feed. There are various techniques to add fresh Ulva.

A. Fresh Ulva Addition from Marine Water Bodies Directly:
Ulva is gathered from various aquatic water bodies and cleaned with sterilized marine water to get rid of epiphytes, after that set in laboratory conditions, in 5-L marine water containers, at 25°C, with a photoperiod of 12 h:12 h light: dark, with fluorescent light tubes of 75 W; besides, using Provasoli medium at a constant concentration of 0.5 ppm of nitrogen in water for two weeks before the feeding trial [72].
B. Fresh Ulva addition after Culturing:

Ulva is enriched with nitrogen and given 5-6 volume exchanges per day of filtered water pumped from the sea at a depth of 20 meters (41 ppt, 19.5-25.3°C). Ulva thalli that have been separated from the sea are grown in 1m2, 600-L tanks that are vigorously agitated [81,82]. A concentrated solution of inorganic nutrients containing disodium phosphate and ammonium sulphate is added to the media (at fluxes determined by the experimental treatment). Every morning, the cultures receive the solution over a 4-hour period, which is regarded to be sufficient for Ulva spp. to fulfil its daily ammonia-N needs [83].

Ammonia-N is added at concentrations ranging from 0.5 g (“low-N” Ulva culture) to 10 g (“high-N” culture). These levels are chosen based on Neori, et al. [82], which stated that various N-fluxes would provide Ulva with noticeably altered tissue-nitrogen levels while maintaining sufficient production to permit harvesting for feeding. Several Ulva cultures, both low-N and high-N, are developed. Once a week, the algae are replenished at their original density after being centrifuged (at 500 rpm for 3 min) to remove surface water and weighed to estimate biomass production.

C. Fresh Spores and Germlings of Ulva Addition
To stimulate gametogenesis, Ulva spp. thalli are gathered from submerged limestone rocks and treated with a cold (4°C) treatment. the Ulva thalli are placed between wet newspaper and then refrigerated. After 7 days of cold treatment, each of the five 400 L tanks is loaded with a modified culture medium with 10 kg of the blotted wet weight of Ulva thalli [84], that lacked sodium meta silicate, PII metals, and vitamin stock solutions. Each tank carried three horizontally stacked baskets of 12, 30 x 60-centimeter PVC plates. Only light aeration is used in the tanks to decrease water movement and allow for optimum spore adhesion. Ulva thalli are withdrawn from the 5 tanks after six days, and the germlings seeded PVC plates are distributed into three 400 L tanks with three containers of 20 plates, all of which are positioned vertically. The modified medium is then used to grow the germlings for 5 weeks, with media replacements occurring every two weeks [80].

Table 5: Studies on the use of Ulva as a powder in fish feed.

Table 6: Studies on the use of Ulva as a powder in crustaceans feed.

Ulva Addition as Powder

As illustrated in Table 5 [85-102] & Table 6[103,104], different Ulva spp. can be added as a powder in crustaceans and fish feed but not to momollusc’seed.

A. Preparation of Ulva as Powder

Ulva spp., a green macro-alga, is collected fresh from the nearshore waters of diverse coastal water bodies or gathered after cultivation. Ulva samples are completely rinsed with salt water, dried in a 40°C oven for 48 hours, ground to powder for proximate analysis, and stored dry until utilized in the diet formulation [49].

B. Ulva Addition as Extract

As illustrated in Table 7 [105-107] & Table 8 [108-112], different Ulva spp. can be added as extract either through injection or on feed for fish and crustaceans but not molluscs.

Table 7: Studies on the use of Ulva as an extract in fish feed.

Table 8: Studies on the use of Ulva as an extract in crustaceans feed.

Bioactive substances classification into various classes is currently unclear and is dependent on the classification’s aim. Because of the ease of characterizing biosynthetic pathways, biosynthetic classifications will not be able to match the scope of pharmacological categorization. According to Croteau, et al. [113], plant bioactive chemicals
are divided into three categories:
a. terpenes and terpenoids (about 25,000 kinds),
b. alkaloids (approximately 12,000 sorts), and
c. phenolic compounds (approximately 8000 types). Furthermore, many bioactive compounds are divided into various families, each with unique structural characteristics based on how they are generated in nature (biosynthesis).

Figure 3

As shown in Figure 3, secondary metabolites, often known as bioactive compounds, are produced in four ways: The four pathways include the mevalonic acid pathway, the non-mevalonate (MEP) pathway, the shikimic acid pathway, and the malonic acid pathway [114]. Either aliphatic amino acids or aromatic amino acids (from the shikimic acid pathway) can create alkaloids. Malonic and shikimic acids can create phenolic chemicals. Terpenes can be made by two different processes: mevalonic acid and MEP.

Furthermore, as illustrated in Figure 4, Ulva bioactive substances can be extracted through many conventional and non-conventional extraction techniques.

Figure 4

Table 9: Effects of different Ulva types dietary inclusion as powder, extract, and fresh on growth performance of fish, crustaceans, and molluscs.

Effects of different Ulva spp. addition on different performance parameters

Growth Performance:

As shown in Table 9 [115-118], adding Ulva meal as a powder generally boosted growth at low levels but had the lowest growth performance at high levels, depending on the specific Ulva species, fish species, and addition method. Diler, et al. [92] discovered that fish fed a diet supplemented with 0, 5, 10, 15, and 20 percent U. rigida that replaced wheat meal starch showed the best growth by 5 percent meal inclusion, while fish fed a diet supplemented with 20 percent Ulva meal showed the worst growth performance. The growth of European seabass fry (Dicentrarchus labrax L.) was also positively impacted by the addition of 5% U. lactuca powder to the meal [51]. When compared to a control diet, the growth rate of Nile tilapia fingerlings (Oreochromis niloticus) (18.47±1.25 gm) fed meals containing 2.5 and 5% of U. lactuca powder dramatically increased by 53 and 68% respectively [52]. Additionally, Abdel Warith, et al. [41] reported that African catfish (Clarias gariepinus) fed diets containing 20 or 30 percent U. lactuca meal had the worst growth performance and feed utilization compared to control diets. These adverse effects were attributed to the experimental diet’s low protein content, high ash content, and high level of soluble fiber [41]. In contrast, Abdel-Aziz and Ragab discovered that increasing the content of U. fasciata powder in the feeding of Rabbit fish fry (Siganus rivulatus) by 50% or 100% increased growth rate [48]. Nile tilapia (Oreochromis niloticus) growth was accelerated by up to 10% Ulva sp. in the fish feed [88]. Ulva spp. supplementation increased final body weight, weight gain, and specific growth rate in grey mullet (Liza ramada) considerably with an increase in Ulva spp. level up to 28% in the fish diet [91]. On the other hand, Legarda, et al. [85] found that increasing the amount of U. fasciata powder (5, 10, and 20 g kg-1) had no impact on the somatic characteristics and growth performance of (Seriola dorsalis). The growth parameters of European seabass (Dicentrarchus labrax) fed a diet supplemented with 2.5 and 7.5 percent Ulva meal were unaffected [93]. The discrepancies in results between studies may be due to different Ulva spp. and seasonal variables, as well as variations in the make-up of control diets.

As for the relationship of using Ulva extracts on growth performance parameters, when Nile tilapia (Oreochromis niloticus) were fed various quantities of U. clathrate [108] and U. fasciata [116]as extract, no significant effects were observed. But, Akbary and Aminikhoei [115] discovered that feeding grey mullet (Mugil cephalus) on 10 mg/ kg of U. rigida extract resulted in a faster growth rate. Additionally, Yamasaki, et al. [117]; Ge et al. [109]; Akbary and Aminikhoei [115] reported that shrimp development improved because of the use of Ulva extract.

Regarding the impact of applying fresh Ulva on growth efficiency, the results showed that a 50 percent fresh U. fasciata replacement in rabbit fish fry (Siganus rivulatus) (0.18 g) diet resulted in the highest final weight, total weight gain, average daily gain, growth rate, and specific growth rate when compared to a 100 percent replacement [44]. The growth performance of pacific white shrimp (Litopenaeus vannamei) can be significantly improved by substituting up to 50% fresh U. lactuca for commercial feed [19]. Additionally, fresh U. clathrate improved the growth rate of pacific white shrimp (Litopenaeus vannamei) and brown shrimp (Farfantepenaeus californiensis) according to studies by Peña‐Rodríguez, et al. [71]; Gamboa-Delgado, et al. [73]; Cruz-Suárez, et al. [2].

In terms of how employing Ulva spores and germlings affects growth performance, the inclusion of fresh Ulva lens and Ulva spp. germlings improved the growth performance of molluscs, according to Daume et al. [75]; Shpigel, et al. [55]; Corazani and Illanes [76]; Boarder [20]. On the other hand, the growth rate of abalone (Haliotis midae and Haliotis laevigata) was found to be lowered by fresh Ulva spp.’ spores [77] and fresh Ulva spp.’ Germlings [80], respectively. It is unclear whether the Ulva species’ active ingredient is responsible for improving growth; instead, the advantage has been attributed to the plants’ mineral and vitamin content, lipid mobilization, and improved absorption and digestion efficiency ratios.

Table 10: Effects of different Ulva types dietary inclusion on feed intake.

Feed Intake:

When Nile tilapia (Oreachromis niloticus)[18] and black tiger shrimp (Penaeus monodon juvenile) [104] were fed U. fasciata as extract and U. lactuca as powder respectively, found no influence on feed intake, as indicated in Table 10 [104,118]. In contrast, Yıldırım, et al. [118] reported that fish groups fed with the diet containing U. lactuca powder of Rainbow Trout (Oncorhynchus mykiss) (32.96 0.29g) had lower daily dry feed intake and total feed intake than those of the control group. Moreover, according to studies done on abalone and fish, dimethyl-beta-propionthein (DMTP) and dimethyl sulfonyl propionate (DMSP); besides, other compounds found in seaweed extracts, such as amino acids, phosphatidylcholine, digalactosyl-diacylglycerol, 6-sulfoquinovosyldiacylglycerol, and phosphatidylethanolamine, can act as attractants in pelleted diets [53, 119,120]. According to Cruz Suárez, et al. [53], these compounds act as attractants and enhance shrimp growth performance, feed efficiency, and feed intake.

Table 11: Effects of different Ulva types dietary inclusion on FCR.

Feed Conversion Ratio (FCR):

As shown in Table 11, in a meal containing 20% fresh U. clathrate, FCR was decreased in young European Abalone (Haliotis tuberculate) [71]. Furthermore, in European abalone (Haliotis tuberculate) FCR was declined by U. lactuca [55]. Similarly, fresh U. clathrata decreased FCR in pacific white shrimp (litopenaeus vannamei) (3.5 g) [2]. According to Vyas [43], adding 10 percent Ulva meal powder to (Labeo rohita) fry (0.62 0.04 g) diet produced the lowest FCR. In addition, the impact of Ulva spp. as powder on FCR in crustaceans differed between studies. Cruz‐Suárez, et al. [53] discovered that a concentration of 33 g kg-1 Ulva clathrate improved FCR in white shrimp (Litopenaeus vannamei) (1.6 g), but Elizondo-González et al. [72] found that the concentration of 3 percent U. lactuca improved FCR in pacific white shrimp (Litopenaeus vannamei) (0.59 0.09 g). In contrast, Serrano Jr, et al. [104] showed no effect on FCR in young black tiger shrimp after 90 days of feeding U. lactuca at a rate of 15% and 30% replacement of soybean meal (Penaeus monodon). Additionally, after a 90- day feeding trial using various quantities of U. fasciata extract, Nile tilapia (Oreachromis niloticus) fed the extract showed no influence on the FCR [18].

Table 12: Effects of different Ulva types dietary inclusion on PER.

Protein Efficiency Ratio (PER)

PER in brown shrimp (Farfantepenaeus californiensis) (0.12 g) was shown to grow at a rate of 30 g wet weight per tank of fresh U. clathrate (Table 12) [74]. Furthermore, Vyas [43] found that integrating Ulva meal increased PER in (Labeo rohita) fry by the lowest concentration of 10 percent, and this result correlated with Nakagawa et al. [103]. Additionally, Japanese Flounder (Paralihthys olivaceus) (5 g) had the highest protein efficiency ratio when fed the lowest concentration of Ulva meal (2 percent) [96]. It has been reported that algae can boost the absorption and assimilation of dietary protein [121] or adjust lipid metabolism [103]. On the other hand, U. lactuca powder substituted for wheat meal showed reduced protein retention and protein efficiency ratio by 10% [118]. Furthermore, the PER of black tiger shrimp juveniles (Penaeus monodon) fed a U. lactuca diet was comparable throughout the experimental shrimp groups [104]. Similarly, no effect of U. fasciata methyl extract on PER in Nile tilapia (Oreachromis niloticus) (1.320.12 g) was found by Abo‐Raya ,et al. [18].

Immune and Ani-Oxidant Parameters

As shown in Table 13 [122-124], we are not aware of any studies on the impact of fresh Ulva on the defense mechanisms and antioxidant activity of fish or crustaceans. On the other hand, few studies, including one by Peixoto, et al. [124], showed that European seabass (Dicentrarchus labrix) (25.5±4.1 g) fed Ulva powder at 2.5 and 7.5 percent had better innate immune and antioxidant responses. Additionally, Nile tilapia’s immunological response was stimulated by 5% U. rigida powder [95]. Furthermore, most studies have shown that Ulva extract improves immunological and antioxidant activities in fish [18,104,107,108,123,125,126]. Additionally, most research demonstrated that higher Ulva extract concentrations can have undesirable effects. 10 mg/kg of Ulva rigida water extract enhanced lysozyme, phagocytic, and respiratory burst activities in grey mullet (Mugil cephalus) than 5 and 15 mg/kg [115]. Like this, U. fasciata methyl extract enhanced lysozyme, phagocytic, and antioxidant activities in Nile tilapia (Oreachromis niloticus) (1.32±0.12 g) at a dose of 100 mg/ kg when compared to 50 and 150 mg/kg [18]. Moreover, Ulva extract has also been shown to improve immunological and antioxidant activities in crustaceans [109,111,112,126] . The only study that we are aware of that used Ulva extract administered intraperitoneally in fish discovered that Senegalese sole’s immune response was improved by 0.5 mg/fish U. Ohnoi extract [122]. According to all of this research, the presence of several bioactive substances such as 9-octadecenoic acid [127], hexadecanoic acid [128], phytol [129-131], 13-octadecenoic acid [132], arachidonic acid [133], and neophytadiene [130,131], could be connected to the greater lysozyme activity, phagocytic activity, and WBCs count.

Table 13: Effects of different Ulva types dietary inclusion on immune and ani-oxidative parameters.

Haemato-Biochemical Parameters:

No investigations on fish and crustaceans by fresh Ulva demonstrated impacts on haemato-biochemical activities, as shown in Table 14, like immune and antioxidant responses. On the other hand, Seriola dorsalis given 20g/kg U. fasciata powder had a higher haematocrit (7.93±0.24 g) (Legarda et al., 2021)[51]. U. fasciata methyl extract improved haemato-biochemical parameters in Nile tilapia (Oreachromis niloticus) [18]. These results were suggested due to the presence of palmitic acid (17.25 %) and oleic acid (10.25 [18]. In contrast, research by Nakagawa [102] shown that U. pertusa at concentrations of 2.5, 5.0, 10.0, and 15.0 percent replaced fish meal, inhibited lipid buildup in intraperitoneal body fat in Black Sea bream (Acanthopagrus schlegeli). Additionally, Nile tilapia fingerlings (Oreochromis niloticus) fed U. lactuca meal powder with a concentration of 2.5 and 5 percent exhibited no significant influence on liver enzyme activity, serum total protein, globulin, and albumin [52].

Table 14: Effects of different Ulva types dietary inclusion on Haemato-biochemical parameters.

Table 15: Effects of different Ulva types of dietary inclusion on Antioxidant and immune-related genes expressions.

Antioxidant and Immune-Related Genes Expressions:

According to Table 15. In Pacific white shrimp (Litopenaeus vannamei), fresh U. clathrate (30.01g) was found to trigger immune and lipid metabolism genes [70]. Injecting U. ohnoi extract intraperitoneally led to the activation of immune-related genes like toll-like receptors (TLRs) in Senegalese sole (Solea senegalensis) [122]. Additionally, it was shown that U. rigida extract increased the expression of interleukin-1 (IL-1) in turbot peritoneal leucocytes [107]. To the best of our knowledge, no studies utilizing Ulva meal powder on fish and crustaceans have revealed the expression of immune and antioxidant- related genes.

Growth-Related Genes Expressions:

To our knowledge, Abo‐Raya, et al. [18] is the only study that has examined the impact of Ulva species on growth-related genes in fish. They discovered that growth hormone (GH) and Insulin-like growth factor-1 (ILGF-1) expressions in Nile tilapia fed U. fasciata methyl extract made slight and non-significant increases, and they attributed these findings to the presence of bioactive compounds that inhibit growth; for example, clionasterol [Gamma sitosterol (C29H50O)] that has been mentioned to influence cholesterol synthesis in intestinal cell [18,134,135].

Evaluation and future work

This review has discussed the potential of Ulva spp. as an alternative sustainable feed additive.
A. The outcomes of most Ulva research clearly show the following:
a) Ulva can be used in different forms (fresh, powder, and extract) and may have positive, negative, and non-effect on the different performance parameters.
b) Ulva contains numerous significant and useful bioactive compounds such as oleic acid, hexadecenoic acid, phytol, neophytadiene, arachidonic acid, and clionasterol which have significant effects on growth, haemato-biochemical, immune, and antioxidant parameters.
B. Ulva is a promising feed additive for fish, crustaceans, and molluscs; in addition, it can be a sustainable aquaculture resource in the future due to:
a) It’s wide geographical composition, dispersion, and advantages over terrestrial plants; besides, it can generate a thriving and lucrative industry for coastal fishing communities.
b) When compared to the number of aquatic organisms that perish every day throughout the world and the negative effects of antibiotics on aquatic species and people, the extraction of Ulva bioactive substances is affordable.
C. On the other hand, in all the published studies involving Ulva, there are numerous research gaps:
a) Most research indicated that using Ulva at high doses had adverse effects; therefore, determining the appropriate concentration is vital. Therefore, regression statistical methods are more accurate than ANOVA since it is simple to determine the appropriate concentration to affect the various parameters.
b) Because all extracts contained a variety of bioactive substances, including both harmful and beneficial ones with varying concentrations, it is impossible to be certain of the reasons for the effects in any research. As a result, all researchers built the reasons for their results on the expectation.
c) Even though all research focused on showing how Ulva affected growth performance, nearly only one of them showed how Ulva affected the genes involved in growth. Additionally, no studies highlighted how Ulva as fresh affected haematological, biochemical, immunological, and oxidative parameters.
d) Most of the research used traditional methods of extraction, such as Maceration, for ease of extraction, these methods have severe drawbacks, such as low extraction selectivity and heat breakdown of thermo-labile compounds.
D. Therefore, future research should include the following:
a. Before examining the impacts of Ulva as powder, researchers must first study the effects of Ulva as an extract to identify any potentially dangerous or beneficial bioactive compounds.
b. Researchers should concentrate on using non-conventional extraction techniques to extract bioactive ingredients and be interested in learning how growth-related genes are affected.
c. The researchers must do additional studies to identify the precise bioactive ingredient that has the exact impact on the various studied parameters and not just to do expectations for how the extract responded. Therefore, using the liquid-liquid partition technique, the extract must be divided into three parts (hexane, chloroform, and ethyl acetate). Each part must then be tested again for various activities, and once it is known which part has the desired effect, fractionation and isolation of the precise effective bioactive compounds must be done using an open-column chromatography system [136].

Ulva is a green macro-alga responsible for the disastrous green tides seen all over the world. These green blooms are a result of human activity. Ulva blooms mostly occur in shallow seas, and this alga’s decomposition can release potentially harmful gases. Ulva has undergone in vivo testing for its pharmacological effects as an antioxidant, an anti-inflammatory, and a growth promoter. Furthermore, Ulva is a promising feed additive that can be utilized in the aquaculture industry. According to numerous studies, isolating and extracting its extracts needs a few steps, procedures, and strategies. Moreover, it can also be used fresh and in powder form. However, it’s important to be cautious while choosing the right dosage. Future studies should prioritize their research on Ulva’s biological activity and other health advantages since there is currently a dearth of information, particularly about its extract.

This study was not financially supported by any funding organization.

This article does not contain any experiments with humans or animals.

The authors declare that they have NO conflict of interest that might be perceived to influence the discussion reported in this review.

All authors contributed equally to this work (writing the main manuscript text, preparing figures and tables, and reviewing the manuscript).

All data used has references that can be used to access it and no permissions are required.

1. Besada V, Andrade J M, Schultze F, González J J (2009) Heavy metals in edible seaweeds commercialized for human consumption. Journal of Marine Systems 75(1-2): 305-313.
2. Cruz Suárez L E, León A, Peña Rodríguez A, Rodríguez Peña G, Moll B, et al. (2010) Shrimp/Ulva co-culture: A sustainable alternative to diminish the need for artificial feed and improve shrimp quality. Aquaculture 301(1-4): 64-68.
3. Lahaye M, Jegou D (1993) Chemical and physical-chemical characteristics of dietary fibres from Ulva lactuca (L.) Thuret and Enteromorpha compressa (L.) Grev. Journal of Applied Phycology 5: 195-200.
4. McHugh DJ (2003) A guide to the seaweed industry FAO Fisheries Technical Paper 441. Food and Agriculture Organization of the United Nations Rome pp. 110.
5. Dibenedetto A (2012) 4 Production of aquatic biomass and extraction of bio-oil. In: Biorefinery: From Biomass to Chemicals and Fuels. De Gruyter pp. 81-100.
6. Alsufyani T, Engelen A H, Diekmann O E, Kuegler S, Wichard T (2014) Prevalence and mechanism of polyunsaturated aldehydes production in the green tide forming macroalgal genus Ulva (Ulvales, Chlorophyta). Chemistry and physics of lipids 183: 100-109.
7. Herron MD, Hackett JD, Aylward FO, Michod RE (2009) Triassic origin and early radiation of multicellular volvocine algae. Proceedings of the National Academy of Sciences 106(9): 3254-3258.
8. Verbruggen H, Ashworth M, LoDuca ST, Vlaeminck C, Cocquyt E, et al. (2009) A multi-locus time-calibrated phylogeny of the siphonous green algae. Molecular phylogenetics and evolution 50(3): 642-653.
9. Kreft H, Jetz W (2007) Global patterns and determinants of vascular plant diversity. Proceedings of the National Academy of Sciences 104(14): 5925-5930.
10. Becker B, Marin B (2009) Streptophyte algae and the origin of embryophytes. Annals of botany 103(7): 999-1004.
11. Cocquyt E, Verbruggen H, Leliaert F, De Clerck O (2010) Evolution and cytological diversification of the green seaweeds (Ulvophyceae). Molecular biology and evolution 27(9): 2052-2061.
12. Mine I, Menzel D, Okuda K (2008) Morphogenesis in giant-celled algae. International Review of Cell and Molecular Biology 266: 37-83.
13. Littler M M, Littler D S, Brooks B L (2005) Extraordinary mound building Avrainvillea (Chlorophyta): the largest tropical marine plants. Coral Reefs 24(4): 555-555.
14. Vroom P S, Smith C M (2003) Life without cells. Biologist 50: 222-226.
15. Chisholm J, Dauga C, Ageron E, Grimont P, Jaubert J (1996) 'Roots' in mixotrophic algae. Nature 381: 382-382.
16. Smetacek V, Zingone A (2013) Green and golden seaweed tides on the rise. Nature 504: 84-88.
17. Teichberg M, Fox S E, Olsen Y S, Valiela I, Martinetto P, et al. (2010) Eutrophication and macroalgal blooms in temperate and tropical coastal waters: Nutrient enrichment experiments with Ulva spp. Global Change Biology 16(9): 2624-2637.
18. Abo Raya M H, Alshehri K M, Abdelhameed R F, Elbialy Z I, Elhady S S, et al. (2021). Assessment of growth‐related parameters and immune-biochemical profile of nile tilapia (oreochromis niloticus) fed dietary ulva fasciata extract. Aquaculture Research 52(7): 3233-3246.
19. Pallaoro M F, do Nascimento Vieira F, Hayashi L (2016) Ulva lactuca (Chlorophyta, Ulvales) as co-feed for Pacific white shrimp. Journal of Applied Phycology 28: 3659-3665.
20. Boarder S J (2001) Comparative performances of juvenile Haliotis roei fed on enriched Ulva rigida and various artificial diets. J Shellfish Res 20(2): 653-657.
21. da Silva Copertino M, Tormena T, Seeliger U (2009) Biofiltering efficiency, uptake and assimilation rates of Ulva clathrata (Roth) J. Agardh (Clorophyceae) cultivated in shrimp aquaculture wastewater. Journal of Applied Phycology 21: 31-45.
22. Lobban C S, Wynne M J (1981) The biology of seaweed. Univ of California Press p. 77.
23. Sivakumar K, Kannappan S, Dineshkumar M, Patil P K (2014) Evaluation of marine macro alga, Ulva fasciata against bio-luminescent causing Vibrio harveyi during Penaeus monodon p. 1-7.
24. Cartel J E (2020) Experimental Validation of a Performance Model of a Biofiltration System. In 2019 IEEE 11th International Conference on Humanoid, Nanotechnology Information Technology Communication and Control Environment and Management (HNICEM) IEEE p. 1-6.
25. Alrawagh OM (2018) Post treatment of secondary wastewater effluent for irrigation purposes using Ulva lactuca algae. PhD Thesis. Al-Azhar University, Gaza, Egypt p. 17-18.
26. Algarum I N, Island B, Huisman W A J, Huisman J (1753) Ulva lactuca Linnaeus 1753(2): 561-1200.
27. Hernández Garibay E, Zertuche González J A, Pacheco Ruíz I (2011) Isolation and chemical characterization of algal polysaccharides from the green seaweed Ulva clathrata (Roth) C. Agardh Journal of Applied Phycology 23(3): 537-542.
28. Dobretsov S V, Qian P Y (2002) Effect of bacteria associated with the green alga Ulva reticulata on marine micro-and macrofouling. Biofouling 18(3): 217-228.
29. Leiro J M, Castro R, Arranz J A, Lamas J (2007) Immunomodulating activities of acidic sulphated polysaccharides obtained from the seaweed Ulva rigida Agardh. International immunopharmacology 7(7): 879-888.
30. Heesch S (2007) Genetic diversity and possible origins of New Zealand populations of Ulva, MAF Biosecurity New Zealand. p. 1-9.
31. Aguilar Rosasl R, Aguilar Rosas L E, Shimada S (2008) First record of Ulva pertusa Kjellman (Ulvales, Chlorophyta) in the Pacific coast of Mexico. Algae 23(3): 201-207.
32. Hiraoka M, Ohno M, Kawaguchi S, Yoshida G (2004) Crossing test among floating Ulva thalli forminggreen tide'in Japan. Hydrobiologia 512: 239-245.
33. Jin D Q, Lim C S, Sung JY, Choi H G, Ha I, et al. (2006) Ulva conglobata, a marine algae, has neuroprotective and anti-inflammatory effects in murine hippocampal and microglial cells. Neuroscience letters 402(1-2): 154-158.
34. Matsumoto K, Shimada S (2015) Systematics of green algae resembling Ulva conglobata, with a description of Ulva adhaerens nov.(Ulvales, Ulvophyceae). European Journal of Phycology 50(1): 100-111.
35. Gao G, Zhong Z, Zhou X, Xu J (2016) Changes in morphological plasticity of Ulva prolifera under different environmental conditions: a laboratory experiment. Harmful algae 59: 51-58.
36. Hiraoka M, Shimada S, Uenosono M, Masuda M (2004b) A new green-tide-forming alga, Ulva ohnoi Hiraoka et Shimada sp. nov.(Ulvales, Ulvophyceae) from Japan. Phycological research 52(1): 17-29.
37. Leskinen E, Alstom rapaport C, Pamilo P (2004) Phylogeographical structure, distribution and genetic variation of the green algae Ulva intestinalis and compressa (Chlorophyta) in the Baltic Sea area. Molecular ecology 13(8): 2257-2265.
38. Pratiwi D Y, Pratiwy F M (2021) Comparison of Ulva lactuca and Ulva clathrata as ingredients in Litopenaeus vannamei p. 1-2.
39. Corral Rosales D C, Cruz Suárez L E, Ricque Marie D, Rodríguez Jaramillo C, Palacios E (2018) Modulation of reproductive exhaustion using Ulva clathrata in Pacific white shrimp Litopenaeus vannamei (Boone, 1931) broodstock during commercial maturation. Aquaculture Research 49(12): 3711-3722.
40. Laramore S, Baptiste R, Wills P S, Hanisak M D (2018) Utilization of IMTA-produced Ulva lactuca to supplement or partially replace pelleted diets in shrimp (Litopenaeus vannamei) reared in a clear water production system. Journal of Applied Phycology 30: 3603-3610.
41. Abdel Warith A W A, Younis E S M, Al Asgah N A (2016) Potential use of green macroalgae Ulva lactuca as a feed supplement in diets on growth performance, feed utilization and body composition of the African catfish, Clarias gariepinus. Saudi Journal of Biological Sciences 23(3): 404-409.
42. Yıldırım Ö, Ergün S, Yaman S, Türker A (2009) Effects of two seaweeds (Ulva lactuca and Enteromorpha linza) as a feed additive in diets on growth performance, feed utilization, and body composition of rainbow trout (Oncorhynchus mykiss) 15(3): 455.
43. Vyas A (2016) Effect of sea weed (Ulva sp.) as a feed additive in diet on growth and survival of Labeo rohita FRY. J Exp Zool India 19: 771-778.
44. Abdel Aziz M, Ragab M (2017) Effect of Use Fresh Macro Algae (Seaweed) Ulva fasciata and Enteromorpha flaxusa With or Without Artificial Feed on Growth Performance and Feed Utilization of Rabbitfish (Siganus rivulatus) fry. Journal of Aquaculture Research and Development 8: 482.
45. Peixoto MJ, Salas Leitón E, Pereira LF, Queiroz A, Magalhães F, et al. (2016) Role of dietary seaweed supplementation on growth performance, digestive capacity and immune and stress responsiveness in European seabass (Dicentrarchus labrax). Aquaculture Reports 3: 189-197.
46. Valente L, Gouveia A, Rema P, Matos J, Gomes E, et al. (2006) Evaluation of three seaweeds Gracilaria bursa-pastoris, Ulva rigida and Gracilaria cornea as dietary ingredients in European sea bass (Dicentrarchus labrax) juveniles. Aquaculture 252(1): 85-91.
47. Azaza M, Mensi F, Ksouri J, Dhraief M, Brini B, et al. (2008) Growth of Nile tilapia (Oreochromis niloticus) fed with diets containing graded levels of green algae ulva meal (Ulva rigida) reared in geothermal waters of southern Tunisia. Journal of applied ichthyology 24(2): 202-207.
48. Hashim R, Saat M A M (1992) The utilization of seaweed meals as binding agents in pelleted feeds for snakehead (Channa striatus) fry and their effects on growth. Aquaculture 108(3-4): 299-308.
49. Ergün S, Soyutürk M, Güroy B, Güroy D, Merrifield D (2009) Influence of Ulva meal on growth, feed utilization, and body composition of juvenile Nile tilapia (Oreochromis niloticus) at two levels of dietary lipid. Aquaculture International 17: 355-361.
50. Güroy D, Güroy B, Merrifield D, Ergün S, Tekinay A, et al. (2011) Effect of dietary Ulva and Spirulina on weight loss and body composition of rainbow trout, Oncorhynchus mykiss (Walbaum), during a starvation period. Journal of animal physiology and animal nutrition 95(3): 320-327.
51. Wassef E A, El Sayed A F M, Sakr E M (2013) Pterocladia (Rhodophyta) and Ulva (Chlorophyta) as feed supplements for European seabass, Dicentrarchus labrax, fry. Journal of applied phycology 25: 1369-1376.
52. Khalafalla M, M El Hais A e M (2015) Evaluation of seaweeds Ulva rigida and Pterocladia capillaceaas dietary supplements in Nile Tilapia Fingerlings. Journal of Aquaculture Research and Development 6: 1-5.
53. Cruz Suárez L, Leon A, Pena Rodriguez A, Rodriguez Pena G, Moll B et al. (2008) Shrimp and green algae co-culture to optimize commercial feed utilization. In: ISNF XIII international symposium on nutrition and feeding in fish Florianopolis: 304-333
54. Cruz Suárez L, Tapia Salazar M, Nieto López M, Guajardo Barbosa C, Ricque Marie D (2009) Comparison of Ulva clathrata and the kelps Macrocystis pyrifera and Ascophyllum nodosum as ingredients in shrimp feeds. Aquaculture Nutrition 15(4): 421-430.
55. Shpigel M, Ragg N L, Lupatsch I, Neori A (1999) Protein content determines the nutritional value of the seaweed Ulva lactuca L for the abalone Haliotis tuberculata and H. discus hannai Ino. Journal of Shellfish Research 18(1): 227-233.
56. Bindu M, Sobha V (2004) Conversion efficiency and nutrient digestibility of certain seaweed diets by laboratory reared Labeo rohita (Hamilton). Indian J Exp Biol 42(12): 1239-1244.
57. Marinho Soriano E, Fonseca P, Carneiro M, Moreira W (2006) Seasonal variation in the chemical composition of two tropical seaweeds. Bioresource technology 97(18): 2402-2406.
58. Wong K H, Cheung P C (2000) Nutritional evaluation of some subtropical red and green seaweeds: Part I-proximate composition, amino acid profiles and some physico-chemical properties. Food chemistry 71(4): 475-482.
59. Fleurence J (1999) Seaweed proteins: Biochemical, nutritional aspects and potential uses. Trends in food science & technology 10(1): 25-28.
60. Ackman R, Sebedio J, Ratnayake W (1981) Structure determinations of unsaturated fatty acids by oxidative fission. In: Methods in enzymology. Elsevier 72: 253-276.
61. Kraan S (2013) Mass-cultivation of carbohydrate rich macroalgae, a possible solution for sustainable biofuel production. Mitigation and Adaptation Strategies for Global Change 18: 27-46.
62. Sudhakar K, Mamat R, Samykano M, Azmi W, Ishak W, et al. (2018) An overview of marine macroalgae as bioresource. Renewable and Sustainable Energy Reviews 91: 165-179.
63. Burkholder J M, Mason K M, Glasgow Jr H B (1992) Water-column nitrate enrichment promotes decline of eelgrass Zostera marina: Evidence from seasonal mesocosm experiments. Marine ecology progress series 81: 163-178.
64. Yoza B A, Masutani E M (2013) The analysis of macroalgae biomass found around Hawaii for bioethanol production. Environmental technology 34(13-16): 1859-1867.
65. Reyimu Z, Özçimen D (2017) Batch cultivation of marine microalgae Nannochloropsis oculata and Tetraselmis suecica in treated municipal wastewater toward bioethanol production. Journal of Cleaner Production 150: 40-46.
66. Robledo D, Gasca Leyva E, Fraga J (2013) Social and economic dimensions of carrageenan seaweed farming in Mexico. Social and Economic Dimensions of Carrageenan Seaweed Farming. Fisheries and Aquaculture Technical: 580.
67. Buck B H, Nevejan N, Wille M, Chambers M D, Chopin T (2017) Offshore and multi-use aquaculture with extractive species: Seaweeds and bivalves. In: Aquaculture perspective of multi-use sites in the open ocean. Springer Cham: 23-69.
68. Largo D B, Diola A G, Marababol M S (2016) Development of an integrated multi-trophic aquaculture (IMTA) system for tropical marine species in southern Cebu, Central Philippines. Aquaculture Reports 3: 67-76.
69. Brito L O, Arantes R, Magnotti C, Derner R, Pchara F, et al. (2014) Water quality and growth of Pacific white shrimp Litopenaeus vannamei (Boone) in co-culture with green seaweed Ulva lactuca (Linaeus) in intensive system. Aquaculture International 22: 497-508.
70. Elizondo Reyna E, Medina González R, Nieto López M G, Ortiz López R, Elizondo González R, et al. (2016) Consumption of Ulva clathrata as a dietary supplement stimulates immune and lipid metabolism genes in Pacific white shrimp Litopenaeus vannamei. Journal of Applied Phycology 28: 3667-3677.
71. Peña Rodríguez A, Magallón Barajas F J, Cruz Suárez L E, Elizondo González R, Moll B (2017) Effects of stocking density on the performance of brown shrimp Farfantepenaeus californiensis co‐cultured with the green seaweed Ulva clathrata. Aquaculture Research 48(6): 2803-2811.
72. Elizondo González R, Quiroz Guzmán E, Escobedo Fregoso C, Magallón Servín P, Peña Rodríguez A (2018) Use of seaweed Ulva lactuca for water bioremediation and as feed additive for white shrimp Litopenaeus vannamei. PeerJ 6: e4459.
73. Gamboa Delgado J, Peña Rodríguez A, Ricque Marie D, Cruz Suárez L E (2011) Assessment of nutrient allocation and metabolic turnover rate in Pacific white shrimp Litopenaeus vannamei co-fed live macroalgae Ulva clathrata and inert feed: Dual stable isotope analysis. Journal of Shellfish Research 30: 969-978.
74. Peña Rodríguez A, Elizondo González R, Nieto López M G, Ricque Marie D, Cruz Suárez L E (2017) Practical diets for the sustainable production of brown shrimp, Farfantepenaeus californiensis, juveniles in presence of the green macroalga Ulva clathrata as natural food. Journal of Applied Phycology 29: 413-421.
75. Daume S, Davidson M, Ryan S, Parker F (2007) Comparisons of rearing systems based on algae or formulated feed for juvenile greenlip abalone (Haliotis laevigata). Journal of Shellfish Research 26(3): 729-735.
76. Corazani D, Illanes J (1998) AQUACULTURE-Growth of juvenile abalone, Haliotis discus hannai Ino 1953 and Haliotis rufescens Swainson 1822, fed with different diets. Journal of Shellfish Research 17: 663-666.
77. Simpson B J, Cook P A (1998) Rotation diets: A method of improving growth of cultured abalone using natural algal diets. Journal of Shellfish Research 17: 635-640.
78. Stuart M, Brown M (1994) Growth and diet of cultivated black-footed abalone, Haliotis iris (Martyn). Aquaculture 127(4): 329-337.
79. Daume S, Huchette S, Ryan S, Day R W (2004) Nursery culture of Haliotis rubra: The effect of cultured algae and larval density on settlement and juvenile production. Aquaculture 236(1): 221-239.
80. Strain L W, Borowitzka M A, Daume S (2006) Growth and survival of juvenile greenlip abalone (Haliotis laevigata) feeding on germlings of the macroalgae Ulva sp. Journal of Shellfish Research 25: 239-247.
81. Vandermeulen H, Gordin H (1990) Ammonium uptake using Ulva (Chlorophyta) in intensive fishpond systems: mass culture and treatment of effluent. Journal of Applied Phycology 2: 363-374.
82. Neori A, Cohen I, Gordin H (1991) Ulva lactuca biofilters for marine fishpond effluents. II. Growth rate, yield and C: N ratio. Botanica Marina 34(6): 483-490.
83. Fujita RnM, Wheeler P A, Edwards R L (1988) Metabolic regulation of ammonium uptake by Ulva rigida (Chlorophyta): A compartmental analysis of the rate-limiting step for uptake 1. Journal of Phycology 24(4): 560-566.
84. Reimann BE, Lewin JM, Guillard RR (1963) Cyclotella cryptica: A new brackish-water diatom species. Phycologia 3: 75-84.
85. Legarda E C, Viana M T, Zaragoza O B D R, Skrzynska A K, Braga A, et al. (2021) Effects on fatty acids profile of Seriola dorsalis muscle tissue fed diets supplemented with different levels of Ulva fasciata from an Integration Multi-Trophic Aquaculture system. Aquaculture 535: 736414.
86. Nakagawa H, Kasahara S, Sugiyama T (1987) Effect of Ulva meal supplementation on lipid metabolism of black sea bream, Acanthopagrus schlegeli (Bleeker). Aquaculture 62(2): 109-121.
87. Marinho G, Nunes C, Sousa Pinto I, Pereira R, Rema P, et al. (2013) The IMTA-cultivated Chlorophyta Ulva spp. as a sustainable ingredient in Nile tilapia (Oreochromis niloticus) diets. Journal of applied phycology 25: 1359-1367.
88. Natify W, Droussi M, Berday N, Araba A, Benabid M (2015) Effect of the seaweed Ulva lactuca as a feed additive on growth performance, feed utilization and body composition of Nile tilapia (Oreochromis niloticus). International Journal of Agronomy and Agricultural Research 7: 85-92.
89. Silva D, Valente L, Sousa Pinto I, Pereira R, Pires M, et al. (2015) Evaluation of IMTA-produced seaweeds (Gracilaria, Porphyra, and Ulva) as dietary ingredients in Nile tilapia, Oreochromis niloticus, juveniles. Effects on growth performance and gut histology. Journal of Applied Phycology 27: 1671-1680.
90. Shpigel M, Guttman L, Shauli L, Odintsov V, Ben Ezra D, et al. (2017) Ulva lactuca from an integrated multi-trophic aquaculture (IMTA) biofilter system as a protein supplement in gilthead seabream (Sparus aurata) diet. Aquaculture 481: 112-118.
91. Elmorshedy I (2010) Using algae and seaweed in the diets of marine fish larvae. Fac. Agri. Saba Bacha, Alexandria University, Egypt. 1-16.
92. Diler I, Tekinay A A, Guroy D, Guroy B K, Soyuturk M (2007) Effects of Ulva rigida on the growth, feed intake and body composition of common carp, Cyprinus carpio L. Journal of Biological Sciences 7(2): 305-308.
93. Peixoto M J, Svendsen J C, Malte H, Pereira L F, Carvalho P, et al. (2016b) Diets supplemented with seaweed affect metabolic rate, innate immune, and antioxidant responses, but not individual growth rate in European seabass (Dicentrarchus labrax). Journal of Applied Phycology 28: 2061-2071.
94. Mustafa G, Wakamatsu S, Takeda T a, Umino T, Nakagawa H (1995) Effects of algae meal as feed additive on growth, feed efficiency, and body composition in red sea bream. Fisheries Science 61(1): 25-28.
95. Güroy B K, Cirik Ş, Güroy D, Sanver F, Tekinay A A (2007) Effects of Ulva rigida and Cystoseira barbata meals as a feed additive on growth performance, feed utilization, and body composition of Nile tilapia, Oreochromis niloticus. Turkish Journal of Veterinary and Animal Sciences 31(2): 91-97.
96. Xu B T, Yamaski S, Hirata H (1993) Supplementary Ulva sp. var. meal level in diet of Japanese flounder, Paralihthys olivaceus. Aquaculture Science 41: 461-468.
97. Wassef E A, El Sayed A F M, Kandeel K M, Sakr E M (2005) Evaluation of Pterocla Dia (Rhodophyta) and Ulva (Chlorophyta) meals as additives to gilthead seabream Sparus aurata diets. Egypt J Aquat Res 31: 321-332.
98. Wassef E, ElMasry M, Eissa M, Mikhail F (2001) Evaluation of® ve supplementary feeds for grey mullet Mugil cephalus L. fry. Egyptian Journal of Nutrition and Feeds 4: 731-741.
99. El Tawil N E (2010) Effects of green seaweeds (Ulva sp.) as feed supplements in red tilapia (Oreochromis sp.) diet on growth performance, feed utilization and body composition. Journal of the Arabian Aquaculture Society 50(2): 179-194.
100. Vadher K K, Vyas A, Parmar P (2016) Effects of seaweed, Gracilaria sp. as feed additive in diets on growth and survival of Labeo rohita. J Exp Zool 19: 771-778.
101. Nakazoe JI (1986) Effect of supplementation of alga or lipids to the diets on the growth and body composition of nibbler Girella punctata Grey. Bull Tokai Reg Fish Res Lab 120: 43-51.
102. Nakagawa H (1993) Optinum level of Ulva meal diet supplement to minimize weight loss during wintering in black sea bream Acanthopagrus schlegeli (Bleeker). Asian Fish Sci 6(2): 139-148.
103. Nakagawa H, Kasahara S, Suggiyama T, Wada I (1984) Usefulness of Ulva-meal as feed supplementary in cultured black sea bream. Aquaculture Science 32: 20-27.
104. Serrano Jr AE, Santizo RB, Tumbokon BLM (2015) Potential use of the sea lettuce Ulva lactuca replacing soybean meal in the diet of the black tiger shrimp Penaeus monodon juvenile. Aquaculture Aquarium, Conservation & Legislation 8: 245-252.
105. Mangott A, Nappi J, Carini ADP, Goncalves P, Hua K, et al. (2020) Ulva lactuca as a functional ingredient and water bioremediator positively influences the hepatopancreas and water microbiota in the rearing of Litopenaeus vannamei. Algal Research 51: 102040.
106. Akbary P, Aminikhoei Z (2018b) Effect of water-soluble polysaccharide extract from the green alga Ulva rigida on growth performance, antioxidant enzyme activity, and immune stimulation of grey mullet Mugil cephalus. Journal of applied phycology 30: 1345-1353.
107. Castro R, Piazzon M, Zarra I, Leiro J, Noya M, et al. (2006) Stimulation of turbot phagocytes by Ulva rigida Agardh polysaccharides. Aquaculture 254: 9-20.
108. Del Rocío Quezada Rodríguez P, Fajer Ávila EJ (2017) The dietary effect of ulvan from Ulva clathrata on hematological-immunological parameters and growth of tilapia (Oreochromis niloticus). Journal of Applied Phycology 29: 423-431.
109. Ge H, Ni Q, Chen Z, Li J, Zhao F (2019) Effects of short period feeding polysaccharides from marine macroalga, Ulva prolifera on growth and resistance of Litopenaeus vannamei against Vibrio parahaemolyticus infection. Journal of Applied Phycology 31: 2085-2092.
110. Corral Rosales C, Ricque Marie D, Cruz Suárez LE, Arjona O, Palacios E (2019) Fatty acids, sterols, phenolic compounds, and carotenoid changes in response to dietary inclusion of Ulva clathrata in shrimp Litopenaeus vannamei Journal of Applied Phycology 31: 4009-4020.
111. Akbary P, Aminikhoei Z (2018a) Effect of polysaccharides extracts of algae Ulva rigida on growth, antioxidant, immune response, and resistance of shrimp, Litopenaeus vannamei against Photobacterium damselae. Aquaculture Research 49: 2503-2510.
112. Selvin J, Huxley A, Lipton A (2004) Immunomodulatory potential of marine secondary metabolites against bacterial diseases of shrimp. Aquaculture 230: 241-248.
113. Croteau R, Kutchan TM, Lewis NG (2000) Natural products (secondary metabolites). Biochemistry and molecular biology of plants 24: 1250-1319.
114. Taiz L, Zeiger E (2006) Secondary metabolites and plant defense. Plant physiology 4: 315-344.
115. Akbary P, Aminikhoei Z (2018b) Effect of water-soluble polysaccharide extract from the green alga Ulva rigida on growth performance, antioxidant enzyme activity, and immune stimulation of grey mullet Mugil cephalus. Journal of applied phycology 30: 1345-1353.
116. Abo Raya MH, Alshehri KM, Abdelhameed RF, Elbialy ZI, Elhady SS, et al. (2021b) Assessment of growth‐related parameters and immune‐biochemical profile of nile tilapia (oreochromis niloticus) fed dietary ulva fasciata extract. Aquaculture Research 52: 3233-3246.
117. Yamasaki S, Ali F, Hirata H (1997) Low water pollution rearing by means of polyculture of larvae of Kuruma prawn Penaeus japonicus with a sea lettuce Ulva pertusa. Fisheries science 63: 1046-1047.
118. Yıldırım Ö, Ergün S, Yaman S, Türker A (2009) Effects of two seaweeds (Ulva lactuca and Enteromorpha linza) as a feed additive in diets on growth performance, feed utilization, and body composition of rainbow trout (Oncorhynchus mykiss).
119. Sakata K, Tsuge M, Kamiya Y, Ina K (1985) Isolation of a Glycerolipid (DGTH) as a Phago stimulant for a Seahare, Aplysia Juliana, from a Green Alga, Ulva pertusa. Agricultural and biological chemistry 49: 1905-1907.
120. Sakata K, Kato K, Iwase Y, Okada H, Ina K, et al. (1991) Feeding-stimulant activity of algal glycerolipids for marine herbivorous gastropods. Journal of chemical ecology 17: 185-193.
121. Yone Y, Furuichi M, Urano K (1986) Effects of dietary wakame Undaria pinnatifida and Ascophyllum nodosum supplements on growth, feed efficiency, and proximate compositions of liver and muscle of red sea bream. Nippon Suisan Gakkaishi 52: 1465-1468.
122. Ponce M, Zuasti E, Anguís V, Fernández Díaz C (2020) Effects of the sulfated polysaccharide ulvan from Ulva ohnoi on the modulation of the immune response in Senegalese sole (Solea senegalensis). Fish & Shellfish Immunology 100: 27-40.
123. Castro R, Zarra I, Lamas J (2004) Water-soluble seaweed extracts modulate the respiratory burst activity of turbot phagocytes. Aquaculture 229: 67-78.
124. Peixoto MJ, Svendsen JC, Malte H, Pereira LF, Carvalho P, et al. (2016b) Diets supplemented with seaweed affect metabolic rate, innate immune, and antioxidant responses, but not individual growth rate in European seabass (Dicentrarchus labrax). Journal of Applied Phycology 28: 2061-2071.
125. Nasaran D, Huxley V (2013) Effect of Chosen Immunostimulant Induced Immunological Changes in Common Carp (Cyprinus carpio). Dr. E John Jothi Prakash p. 67.
126. Huxley AJ (2002) Studies on the non-specific immunomodulation in Penaeus monodon with special reference to protection against common bacterial pathogens. Manonmaniam Sundaranar University 47: 777-780.
127. Carrillo Pérez C, Camarero C, del Mar M, Alonso de la Torre S (2012) Role of oleic acid in immune system; mechanism of action: A review. Nutrición Hospitalaria 27(4): 978-990.
128. Amarowicz R (2009) Squalene: A natural antioxidant? European journal of lipid science and technology 111: 411-412.
129. Jeong SH (2018) Inhibitory effect of phytol on cellular senescence. Biomedical Dermatology 2: 13.
130. Raman BV, Samuel L, Saradhi MP, Rao BN, Krishna N, et al. (2012) Antibacterial, antioxidant activity and GC-MS analysis of Eupatorium odoratum. Asian Journal of Pharmaceutical and Clinical Research 5: 99-106.
131. Tyagi T, Agarwal M (2017) Phytochemical screening and GC-MS analysis of bioactive constituents in the ethanolic extract of Pistia stratiotes L. and Eichhornia crassipes (Mart.) solms. Journal of Pharmacognosy and phytochemistry 6: 195-206.
132. Krishnamoorthy K, Subramaniam P (2014) Phytochemical profiling of leaf, stem, and tuber parts of Solena amplexicaulis (Lam.) Gandhi using GC-MS. International scholarly research notices p. 1-14.
133. Tallima H, El Ridi R (2018) Arachidonic acid: Physiological roles and potential health benefits–a review. Journal of advanced research 11: 33-41.
134. Haider M, Ashraf M, Azmat H, Khalique A, Javid A, et al. (2015) Nutritional efficacy of acid fish silage in Labeo rohita at growth out stage. Journal of Animal and Plant Sciences 25: 519-526.
135. Richard E, Ostlund J (2002) Phytosterols in human nutrition. Annual Review of Nutrition 22: 533-549.
136. Othman AR, Abdullah N, Ahmad S, Ismail IS, Zakaria MP (2015) Elucidation of in-vitro anti-inflammatory bioactive compounds isolated from Jatropha curcas L. plant root. BMC complementary and alternative medicine 15: 1-10.