EVALUATION OF RECOVERABLE FUNCTIONAL LIPID COMPONENTS OF SEVERAL BROWN SEAWEEDS (PHAEOPHYTA) FROM JAPAN WITH SPECIAL REFERENCE TO FUCOXANTHIN AND FUCOSTEROL CONTENTS(1)

A marine bio-functional lipid, fucoxanthinol, attenuates human colorectal cancer stem-like cell tumorigenicity and sphere formation

Fucoxanthinol (FuOH), an intestinal metabolite form of fucoxanthin (Fx) isolated from marine algae, is known to possess multiple health benefits, such as prevention of human cancer. However, there is little available information about the effects of FuOH on colorectal cancer stem cells (CCSCs) and their contribution to drug resistance, tumorigenesis and cancer recurrence. In the present study, we investigated the anti-proliferative effect of FuOH on two putative CCSCs, CD44^high/EpCAM^high cells and colonospheres (Csps) formed by HT-29 human colorectal cancer cells, and the suppressive effects of FuOH on the growth of xenografted tumor. FuOH significantly inhibited the growth of CD44^high/EpCAM^high cells and disintegrated Csps and induced many condensed chromatin bodies in the cells in a dose-dependent manner. The IC₅₀ value of FuOH for these changes in Csps was 1.8 µM. FuOH down-regulated pAkt (Ser⁴⁷³), PPARβ/δ and PPARγ in Csps. These proteins play a critical role in cell proliferation, the cell cycle, metastasis and extracellular adhesion. Ten days after the administration of FuOH (5 mg/kg body weight) to the mice every 3 to 4 days significantly suppressed the Csps tumorigenesis when compared to the untreated control mice. Our results suggest that FuOH could be used as a chemopreventive agent against human CCSC.

Reduction of HbA1c levels by fucoxanthin-enriched akamoku oil possibly involves the thrifty allele of uncoupling protein 1 (UCP1): a randomised controlled trial in normal-weight and obese Japanese adults

Lifestyle-related problems are becoming a major health threat in East Asian countries. Therefore, finding an efficacious nutraceutical for this population is important. One candidate is fucoxanthin (Fx), a carotenoid abundantly found in edible brown seaweed that has been associated with a number of valuable health-promoting benefits. Unfortunately, clinical studies of Fx are limited. In the present study, we aimed to evaluate the effects of Fx on obesity-related parameters in Japanese subjects harbouring an SNP associated with lifestyle-related problems. In all, sixty normal-weight and obese Japanese adults with BMI over 22 kg/m² were single-blinded and randomly assigned to three Fx-dose cohorts and administered Fx-enriched akamoku oil containing Fx at 0, 1 or 2 mg/d for 8 weeks (n 20 per group). Parameters relating to obesity and serum Fx metabolites were measured before and after intervention, but no significant differences were observed between and within the groups. Despite no changes in visceral fat areas and resting energy expenditures after intervention, we observed a significant decline in HbA1c levels in the 2 mg/d Fx group compared with that in the 0 mg/d group (P < 0·05), which was correlated with an increase in serum fucoxanthinol (Fx metabolite) levels. In addition, HbA1c levels declined more significantly in subjects with G/G alleles of the uncoupling protein 1 (UCP1) gene than in those with the A/A and A/G alleles (P < 0·05). We conclude that although Fx supplementation does not affect visceral fat areas, it may reduce HbA1c levels in those harbouring the thrifty allele of UCP1-3826A/G.

Phylogenetic Tree Analysis of the Cold-Hot Nature of Traditional Chinese Marine Medicine for Possible Anticancer Activity

Traditional Chinese Marine Medicine (TCMM) represents one of the medicinal resources for research and development of novel anticancer drugs. In this study, to investigate the presence of anticancer activity (AA) displayed by cold or hot nature of TCMM, we analyzed the association relationship and the distribution regularity of TCMMs with different nature (613 TCMMs originated from 1,091 species of marine organisms) via association rules mining and phylogenetic tree analysis. The screened association rules were collected from three taxonomy groups: (1) Bacteria superkingdom, Phaeophyceae class, Fucales order, Sargassaceae family, and Sargassum genus; (2) Viridiplantae kingdom, Streptophyta phylum, Malpighiales class, and Rhizophoraceae family; (3) Holothuroidea class, Aspidochirotida order, and Holothuria genus. Our analyses showed that TCMMs with closer taxonomic relationship were more likely to possess anticancer bioactivity. We found that the cluster pattern of marine organisms with reported AA tended to cluster with cold nature TCMMs. Moreover, TCMMs with salty-cold nature demonstrated properties for softening hard mass and removing stasis to treat cancers, and species within Metazoa or Viridiplantae kingdom of cold nature were more likely to contain AA properties. We propose that TCMMs from these marine groups may enable focused bioprospecting for discovery of novel anticancer drugs derived from marine bioresources.

Comparative Studies on the Characteristic Fatty Acid Profiles of Four Different Chinese Medicinal Sargassum Seaweeds by GC-MS and Chemometrics

Sargassum seaweeds produce abundant biomass in China and have long been used as herbal medicine and food. Their characteristic fatty acid (FA) profiles and related potential function in promoting cardiovascular health (CVH) have not been systematically investigated. In this study, FA profiles of four medicinal Sargassum were characterized using GC-MS. Principal component analysis was used to discriminate the four medicinal Sargassum, and orthogonal projection to latent structures discriminant analysis was carried out between the two official species HAI ZAO and between the two folk medicine species HAI QIAN. In all of the algae investigated, the major SFA and MUFA were palmitic and stearic acid, respectively, while the major PUFAs were linoleic, arachidonic, and eicosapentaenoic acid. S. fusiforme and S. horneri had higher concentrations of PUFAs. With respect to CVH, all of the studied species, particularly S. fusiforme, exhibited satisfactory levels such as PUFA/SFA ratio and n-6/n-3 ratio. Each species possesses a unique FA profile and is discriminated clearly. Potential key FA markers (between the two Chinese official species, and between the two folk species) are assessed. The study provides characteristic fatty acid profiles of four Chinese medicinal Sargassum and their related potential function in promoting CVH.

Bioprospecting of Marine Macrophytes Using MS-Based Lipidomics as a New Approach

The marine environment supports a remarkable diversity of organisms which are a potential source of natural products with biological activities. These organisms include a wide variety of marine plants (from micro- to macrophytes), which have been used in the food and pharmaceutical industry. However, the biochemistry and biological activities of many of these macrophytes (namely macroalgae and halophytes, including seagrasses) are still far from being fully explored. Most popular bioactive components include polysaccharides, peptides, phenolics and fatty acids (FAs). Polar lipids (glycolipids, phospholipids and betaine lipids) are emerging as novel value-added bioactive phytochemicals, rich in n-3 FA, with high nutritional value and health beneficial effects for the prevention of chronic diseases. Polar lipids account various combinations of polar groups, fatty acyl chains and backbone structures. The polar lipidome of macrophytes is remarkably diverse, and its screening represents a significant analytical challenge. Modern research platforms, particularly mass spectrometry (MS)-based lipidomic approaches, have been recently used to address this challenge and are here reviewed. The application of lipidomics to address lipid composition of marine macrophytes will contribute to the stimulation of further research on this group and foster the exploration of novel applications.

Spatial and seasonal variations in the biofunctional lipid substances (fucoxanthin and fucosterol) of the laboratory-grown edible Japanese seaweed (Sargassum horneri Turner) cultured in the open sea

This work studied the effect of spatial and seasonal differences on the accumulation of functional lipid components in Sargassum horneri (Turner), an edible Japanese seaweed popularly called Akamoku. S. horneri obtained from Samenoura bay area of Japan was laboratory cultured to evaluate the effect of temperature on the accumulation of total lipids (TL), fucoxanthin (Fx) and fucosterol (Fs) by the alga. The laboratory cultured 3 month old S. horneri were cultured in the open sea in two different geographical locations off Usujiri and Matsushima to evaluate the monthly variations, over a year, in their TL, Fx and Fs contents. S. horneri grown off the Usujiri area accumulated the maximum TL close to 193 mg g^-1 dry weight during the coldest part of the year. Fx and Fs contributed 5.6% and 16.2% of the TL in S. horneri harvested off Usujiri in February. Further, in spite of being the same species and parent stock, S. horneri grown off the Matsushima area accumulated less TL, Fx and Fs as compared to their Usujiri counterparts. Our study clearly indicates the role of temperature and light apart from nutritional profile and depth of waters where the seaweed was grown on the accumulation of functional lipid components in S. horneri.

Inhibition of Ultraviolet B-Induced Expression of the Proinflammatory Cytokines TNF-α and VEGF in the Cornea by Fucoxanthin Treatment in a Rat Model

Ultraviolet B (UVB) irradiation is the most common cause of radiation damage to the eyeball and is a risk factor for human corneal damage. We determined the protective effect of fucoxanthin, which is a carotenoid found in common edible seaweed, on ocular tissues against oxidative UVB-induced corneal injury. The experimental rats were intravenously injected with fucoxanthin at doses of 0.5, 5 mg/kg body weight/day or with a vehicle before UVB irradiation. Lissamine green for corneal surface staining showed that UVB irradiation caused serious damage on the corneal surface, including severe epithelial exfoliation and deteriorated epithelial smoothness. Histopathological lesion examination revealed that levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF), significantly increased. However, pretreatment with fucoxanthin inhibited UVB radiation-induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UVB-induced damage. Moreover, significant preservation of the epithelial integrity and inhibition of stromal swelling were also observed after UVB irradiation in fucoxanthin-treated groups. Pretreatment with fucoxanthin may protect against UVB radiation-induced corneal disorders by inhibiting expression of proinflammatory factors, TNF-α, and VEGF and by blocking polymorphonuclear leukocyte infiltration.

A review of the components of brown seaweeds as potential candidates in cancer therapy

Brown seaweeds have opened new opportunities for the development of novel anticancer agents due to their diverse structural composition and mode of action.

Biological Properties of Fucoxanthin in Oil Recovered from Two Brown Seaweeds Using Supercritical CO2 Extraction

The bioactive materials in brown seaweeds hold great interest for developing new drugs and healthy foods. The oil content in brown seaweeds (Saccharina japonica and Sargassum horneri) was extracted by using environmentally friendly supercritical CO2 (SC-CO2) with ethanol as a co-solvent in a semi-batch flow extraction process and compared the results with a conventional extraction process using hexane, ethanol, and acetone mixed with methanol (1:1, v/v). The SC-CO2 method was used at a temperature of 45 °C and pressure of 250 bar. The flow rate of CO2 (27 g/min) was constant for the entire extraction period of 2 h. The obtained oil from the brown seaweeds was analyzed to determine their valuable compounds such as fatty acids, phenolic compounds, fucoxanthin and biological properties including antioxidant, antimicrobial, and antihypertension effects. The amounts of fucoxanthin extracted from the SC-CO2 oils of S. japonica and S. horneri were 0.41 ± 0.05 and 0.77 ± 0.07 mg/g, respectively. High antihypertensive activity was detected when using mixed acetone and methanol, whereas the phenolic content and antioxidant property were higher in the oil extracted by SC-CO2. The acetone-methanol mix extracts exhibited better antimicrobial activities than those obtained by other means. Thus, the SC-CO2 extraction process appears to be a good method for obtaining valuable compounds from both brown seaweeds, and showed stronger biological activity than that obtained by the conventional extraction process.

Isolation of the molecular species of monogalactosyldiacylglycerols from brown edible seaweed Sargassum horneri and their inhibitory effects on triglyceride accumulation in 3T3-L1 adipocytes

The chemical composition of monogalactosyldiacylglycerols (MGDGs) from brown alga Sargassum horneri and their inhibitory effects on lipid accumulation were investigated in this study. A total of 10 molecular species of MGDGs were identified using nuclear magnetic resonance, alkaline hydrolysis, gas chromatography-flame ionization detector, and high-performance liquid chromatography-tandem mass spectrometry methods. Individual molecular species of MGDGs, including (2S)-1-O-myristoyl-2-O-palmitoleoyl-3-O-β-D-galactopyranosyl-sn-glycerol (1), (2S)-1-O-myristoyl-2-O-linoleyl-3-O-β-D-galactopyranosyl-sn-glycerol (3), (2S)-1-O-palmitoyl-2-O-linolenoyl-3-O-β-D-galactopyranosyl-sn-glycerol (5), (2S)-1-O-myristoyl-2-O-oleyl-3-O-β-D-galactopyranosyl-sn-glycerol (7), (2S)-1-O-palmitoyl-2-O-palmitoleoyl-3-O-β-D-galactopyranosyl-sn-glycerol (8), (2S)-1-O-palmitoyl-2-O-linoleyl-3-O-β-D-galactopyranosyl-sn-glycerol (9), and (2S)-1-O-palmitoyl-2-O-oleyl-3-O-β-D-galactopyranosyl-sn-glycerol (10), were then furnished using semi-preparative high-performance liquid chromatography, and their inhibitory effects on triglyceride (TG) accumulation and free fatty acid (FFA) levels in 3T3-L1 adipocytes were evaluated. Compounds 3 and 9 showed inhibitory effects on TG and FFA accumulation, with TG levels of 1.568 ± 0.2808 and 1.701 ± 0.1460 μmol/L and FFA levels of 0.149 ± 0.0258 and 0.198 ± 0.0229 mequiv/L, respectively, which were more effective than other compounds. The primary structure-activity relationship suggested that linoleyl [18:2(ω-6)] in the sn-2 position played an important role on triglyceride accumulation inhibition.

The major bioactive components of seaweeds and their mosquitocidal potential

Seaweeds are one of the most widely studied natural resources for their biological activities. Novel seaweed compounds with unique chemical structures have been reported for their pharmacological properties. The urge to search for novel insecticidal compound with a new mode of action for development of botanical insecticides supports the relevant scientific research on discovering the bioactive compounds in seaweeds. The mosquitocidal potential of seaweed extracts and their isolated compounds are documented in this review paper, along with the discussion on bioactivities of the major components of seaweeds such as polysaccharides, phenolics, proteins, terpenes, lipids, and halogenated compounds. The effects of seaweed extracts and compounds toward different life stages of mosquito (egg, larva, pupa, and adult), its growth, development, and reproduction are elaborated. The structure-activity relationships of mosquitocidal compounds are discussed to extrapolate the possible chemical characteristics of seaweed compounds responsible for insecticidal properties. Furthermore, the possible target sites and mode of actions of the mosquitocidal seaweed compounds are included in this paper. The potential synergistic effects between seaweeds and commercial insecticides as well as the toxic effects of seaweed extracts and compounds toward other insects and non-target organisms in the same habitat are also described. On top of that, various factors that influence the mosquitocidal potential of seaweeds, such as abiotic and biotic variables, sample preparation, test procedures, and considerations for a precise experimental design are discussed. The potential of active seaweed extracts and compounds in the development of effective bioinsecticide are also discussed.

Extracts from New Zealand Undaria pinnatifida Containing Fucoxanthin as Potential Functional Biomaterials against Cancer in Vitro

This study tested extracts from New Zealand seaweed Undaria pinnatifida containing fucoxanthin, in parallel with pure fucoxanthin, in nine human cancer cell lines, for anticancer activity. Growth inhibition effects of extracts from Undaria pinnatifida were found in all types of cancer cell lines in dose- and time- dependent manners. Cytotoxicity of fucoxanthin in three human non-cancer cell lines was also tested. Compared with pure fucoxanthin, our extracts containing low level of fucoxanthin were found to be more effective in inhibiting the growth of lung carcinoma, colon adenocarcinoma and neuroblastoma. Our results suggest that fucoxanthin is a functional biomaterial that may be used as a chemopreventive phytochemical or in combination chemotherapy. Furthermore, we show for the first time that some unknown compounds with potential selective anti-cancer effects may exist in extracts of New Zealand Undaria pinnatifida, and New Zealand Undaria pinnatifida could be used as a source for either functional biomaterial extraction or production of functional food.

Anticholinesterase and Antioxidant Activities of Fucoxanthin Purified from the Microalga Phaeodactylum Tricornutum

Hot extraction with acetone was the most efficient method for the extraction of fucoxanthin from Phaeodactylum tricornutum. The purified compound resulted in three main peaks consisted of the trans form along with two isomers. The structure of microalgal fucoxanthin was similar to that of brown seaweed, but the ratio of trans- to cis-form was different. The ratio of the cis-form increased as the extraction temperature increased. Fucoxanthin was unstable at high temperature, in acidic condition, and after long period of storage. Fucoxanthin exhibited strong activity against BChE, with an IC50 value of 1.97 mM and mixed inhibition type, whereas it had weak activity against AChE. The IC50 value on reducing power was 0.01 mM, which was much stronger than those of the positive controls. When the amount of cis-isomer increased by 2%, the scavenging activity against DPPH, hydrogen peroxide, superoxide anion, and reducing power decreased by 21.0, 10.3, 16.0, and 19.7%, respectively. Therefore, fucoxanthin could be a useful approach for Alzheimer's disease treatment.

Anti-inflammatory activity of edible brown alga Eisenia bicyclis and its constituents fucosterol and phlorotannins in LPS-stimulated RAW264.7 macrophages

Although individual phlorotannins contained in the edible brown algae have been reported to possess strong anti-inflammatory activity, the responsible components of Eisenia bicyclis have yet to be fully studied. Thus, we evaluated their anti-inflammatory activity via inhibition against production of lipopolysaccharide (LPS)-induced nitric oxide (NO) and tert-butylhydroperoxide (t-BHP)-induced reactive oxygen species (ROS), along with suppression against expression of inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), in RAW 264.7 cells. The anti-inflammatory activity potential of the methanolic extract and its fractions of E. bicyclis was in the order of dichloromethane>methanol>ethyl acetate>n-butanol. The strong anti-inflammatory dichloromethane fraction was further purified to yield fucosterol. From the ethyl acetate fraction, six known phlorotannins were isolated: phloroglucinol, eckol, dieckol, 7-phloroeckol, phlorofucofuroeckol A and dioxinodehydroeckol. We found that these compounds, at non-toxic concentrations, dose-dependently inhibited LPS-induced NO production. Fucosterol also inhibited t-BHP-induced ROS generation and suppressed the expression of iNOS and COX-2. These results indicate that E. bicyclis and its constituents exhibited anti-inflammatory activity which might attribute to inhibition of NO and ROS generation and suppression of the NF-κB pathway and can therefore be considered as a useful therapeutic and preventive approach to various inflammatory and oxidative stress-related diseases.

In vitro antioxidant properties of crude extracts and compounds from brown algae

Research on the bioactives from seaweeds has increased in recent years. Antioxidant activity is one of the most studied, due to the interest of these compounds both as preservatives and protectors against oxidation in food and cosmetics and also due to their health implications, mainly in relation to their potential as functional ingredients. Brown algae present higher antioxidant potential in comparison with red and green families and contain compounds not found in terrestrial sources. In vitro antioxidant chemical methods, used as a first approach to evaluate potential agents to protect from lipid oxidation in foods, confirmed that the brown algae crude extracts, fractions and pure components are comparatively similar or superior to synthetic antioxidants. Particular emphasis on the fucoidan and phlorotannin polymeric fractions is given, considering variations associated with the species, collection area, season, and extraction and purification technologies.

Fucoxanthin content and antioxidant properties of Undaria pinnatifida

This study investigated the fucoxanthin content of New Zealand (NZ) Undaria pinnatifida harvested from two locations in the Marlborough Sounds, New Zealand across its growing season. Fucoxanthin content and antioxidant properties of processed New Zealand U. pinnatifida and commercial wakame from Japan and Korea were further compared. Results showed that U. pinnatifida harvested from Port Underwood had higher fucoxanthin content in the blade compared to Pelorus Sound. The sporophyll also contained a significant amount of fucoxanthin throughout the harvest season, although lower than in the blade. Two antioxidant measurement methods, DPPH and CUPRAC, were utilised to measure antioxidant activities. Processed NZ U. pinnatifida had a lower fucoxanthin content and antioxidant activity than freeze-dried Undaria. Fucoxanthin content and antioxidant activities of NZ processed U. pinnatifida were not significantly different from other commercial samples from Japan and Korea. In conclusion, U. pinnatifida in New Zealand has a great potential to be a food and nutraceutical resource.

Functional properties of carotenoids originating from algae

Carotenoids are isoprenoid molecules which are synthesised de novo by photosynthetic plants, fungi and algae and are responsible for the orange, yellow and some red colours of various fruits and vegetables. Carotenoids are lipophilic compounds, some of which act as provitamins A. These compounds can be divided into xanthophylls and carotenes. Many macroalgae and microalgae are rich in carotenoids, where these compounds aid in the absorption of sunlight. Industrially, these carotenoids are used as food pigments (in dairy products, beverages, etc.), as feed additives, in cosmetics and in pharmaceuticals, especially nowadays when there is an increasing demand by consumers for natural products. Production of carotenoids from algae has many advantages compared to other sources; for example, their production is cheap, easy and environmentally friendly; their extraction is easier, with higher yields, and there is no lack of raw materials or limited seasonal variation. Recently, there has been considerable interest in dietary carotenoids with respect to their antioxidant properties and their ability to reduce the incidence of some chronic diseases where free radicals are involved. Possibly, carotenoids protect cells from oxidative stress by quenching singlet oxygen damage with various mechanisms. Therefore, carotenoids derived from algae could be a leading natural resource in the research for potential functional ingredients.

Towards a better understanding of medicinal uses of the brown seaweed Sargassum in Traditional Chinese Medicine: a phytochemical and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

For nearly 2000 years Sargassum spp., a brown seaweed, has been used in Traditional Chinese Medicine (TCM) to treat a variety of diseases including thyroid disease (e.g. goitre).

AIMS OF THE REVIEW

To assess the scientific evidence for therapeutic claims made for Sargassum spp. in TCM and to identify future research needs.

BACKGROUND AND METHODS

A systematic search for the use of Sargassum in classical TCM books was conducted and linked to a search for modern phytochemical and pharmacological data on Sargassum spp. retrieved from PubMed, Web of Knowledge, SciFinder Scholar and CNKI (in Chinese).

RESULTS AND DISCUSSION

The therapeutic effects of Sargassum spp. are scientifically plausible and may be explained partially by key in vivo and in vitro pharmacological activities of Sargassum, such as anticancer, anti-inflammatory, antibacterial and antiviral activities. Although the mechanism of actions is still not clear, the pharmacological activities could be mainly attributed to the major biologically active metabolites, meroterpenoids, phlorotanins and fucoidans. The contribution of iodine in Sargassum for treating thyroid related diseases seem to have been over estimated.

CONCLUSIONS

The bioactive compounds in Sargassum spp. appear to play a role as immunomodulators and could be useful in the treatment of thyroid related diseases such as Hashimoto's thyroiditis. Further research is required to determine both the preventative and therapeutic role of Sargassum spp. in thyroid health.

STEROL PROFILES IN 18 MACROALGAE OF THE PORTUGUESE COAST(1)

The sterol profiles of dominant macroalgae occurring in the western Portuguese coast were evaluated. An analytical procedure, involving alkaline hydrolysis and extraction followed by separation by reversed-phase HPLC-diode array detection (HPLC-DAD), was optimized for the study of their sterols composition. The validated methodology is short in analysis time (as the compounds are determined in <20 min), sensitive, reproducible, and accurate. It was then successfully applied to the determination of campesterol, cholesterol, desmosterol, ergosterol, fucosterol, stigmasterol, and β-sitosterol in 18 species (three Chlorophyta, five Rhodophyta, and 10 Phaeophyta). The profiles obtained for the several macroalgal species were considerably different. C29 sterols were predominant in Phaeophyta and Chlorophyta (71%-95% of total sterol content), while in Rhodophyta cholesterol content is significantly higher (34%-87%). Among the studied species, Asparagopsis armata Harv. contained the lowest sterol amount (555 mg · kg(-1) dry weight), and Cystoseira tamariscifolia (Huds.) Papenf. the highest one (6,502 mg · kg(-1) dry weight). Data obtained may be helpful in identifying suitable marine sources of sterols, with potential applications in the food and pharmaceutical industries.

Algal chemodiversity and bioactivity: sources of natural variability and implications for commercial application

There has been significant recent interest in the commercial utilisation of algae based on their valuable chemical constituents many of which exhibit multiple bioactivities with applications in the food, cosmetic, agri- and horticultural sectors and in human health. Compounds of particular commercial interest include pigments, lipids and fatty acids, proteins, polysaccharides and phenolics which all display considerable diversity between and within taxa. The chemical composition of natural algal populations is further influenced by spatial and temporal changes in environmental parameters including light, temperature, nutrients and salinity, as well as biotic interactions. As reported bioactivities are closely linked to specific compounds it is important to understand, and be able to quantify, existing chemical diversity and variability. This review outlines the taxonomic, ecological and chemical diversity between, and within, different algal groups and the implications for commercial utilisation of algae from natural populations. The biochemical diversity and complexity of commercially important types of compounds and their environmental and developmental control are addressed. Such knowledge is likely to help achieve higher and more consistent levels of bioactivity in natural samples and may allow selective harvesting according to algal species and local environmental conditions for different groups of compounds.

Characteristics and consumer acceptance of healthier meat and meat product formulations-a review

Awareness of health and nutrition has led to the development of "functional foods" which is a new approach to achieve healthier status thus reducing the risk of diseases. Meat has been highly exploited as a functional ingredient/food in recent years wherein meat has either been modified or incorporated into non meat products. Changing consumer demand has influenced the market for all types of meat. The development and marketing the functional foods can be, however, very challenging compared to the foods that conventionally have a high health image. This review gives the overall perception about importance of using meat/meat products as a functional food.

The allenic carotenoid fucoxanthin, a novel marine nutraceutical from brown seaweeds

Obesity and type 2 diabetes are pathologies with rapidly growing prevalence throughout the world. A few molecular targets offer the most hope for anti-obesity and anti-diabetic therapeutics. One of the keys to success will be the induction of uncoupling protein 1 (UCP1) in abdominal white adipose tissue (WAT) and the regulation of cytokine secretions from both abdominal adipose cells and macrophage cells infiltrated into adipose tissue. Anti-obesity and anti-diabetic effects of fucoxanthin, a characteristic carotenoid found in brown seaweeds, have been reported. Nutrigenomic studies reveal that fucoxanthin induces UCP1 in abdominal WAT mitochondria, leading to the oxidation of fatty acids and heat production in WAT. Fucoxanthin improves insulin resistance and decreases blood glucose levels through the regulation of cytokine secretions from WAT. The key structure of carotenoids for the expression of anti-obesity effect is suggested to be the carotenoid end of the polyene chromophore, which contains an allenic bond and two hydroxyl groups.

Effect of brown seaweed lipids on fatty acid composition and lipid hydroperoxide levels of mouse liver

Brown seaweed lipids from Undaria pinnatifida (Wakame), Sargassum horneri (Akamoku), and Cystoseira hakodatensis (Uganomoku) contained several bioactive compounds, namely, fucoxanthin, polyphenols, and omega-3 polyunsaturated fatty acids (PUFA). Fucoxanthin and polyphenol contents of Akamoku and Uganomoku lipids were higher than those of Wakame lipids, while Wakame lipids showed higher total omega-3 PUFA content than Akamoku and Uganomoku lipids. The levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) in liver lipids of KK-A(y) mouse significantly increased by Akamoku and Uganomoku lipid feeding as compared with the control, but not by Wakame lipid feeding. Fucoxanthin has been reported to accelerate the bioconversion of omega-3 PUFA and omega-6 PUFA to DHA and AA, respectively. The higher hepatic DHA and AA level of mice fed Akamoku and Uganomoku lipids would be attributed to the higher content of fucoxanthin of Akamoku and Uganomoku lipids. The lipid hydroperoxide levels of the liver of mice fed brown seaweed lipids were significantly lower than those of control mice, even though total PUFA content was higher in the liver of mice fed brown seaweed lipids. This would be, at least in part, due to the antioxidant activity of fucoxanthin metabolites in the liver.

Evaluation of the proximate, fatty acid and mineral composition of representative green, brown and red seaweeds from the Persian Gulf of Iran as potential food and feed resources

The proximate, fatty acid and mineral composition were determined for green (Ulva lactuca and Enteromorpha intestinalis), brown (Sargassum ilicifolium and Colpomenia sinuosa) and red (Hypnea valentiae and Gracilaria corticata) seaweeds collected from the Persian Gulf of Iran. Results showed that the seaweeds were high in carbohydrate (31.8-59.1%, dry weight) and ash (12.4-29.9%) but low in lipid content (1.5-3.6%). The protein content of red or green seaweeds was significantly higher (p < 0.05) compared to brown seaweeds. The fatty acid composition of various seaweed lipids varied considerably with 51.9-67.4% of saturates, 22.0-32.9% of monoenes and 9.2-19.1% of polyunsaturated fatty acids (PUFA). E. intestinalis contained the highest total n-3 PUFA content with the lowest n-6/n-3 ratio. Persian Gulf seaweeds contained higher concentrations of all the minerals examined (K, Mg, Fe, Mn, Cu, Zn and Co) compared to terrestrial vegetables. Seaweeds could potentially be used as a food or feed additive in Iran.

Comparative antioxidant activity of edible Japanese brown seaweeds

Japanese edible brown seaweeds, Eisenia bicyclis (Arame), Kjellmaniella crassifolia (Gagome), Alaria crassifolia (Chigaiso), Sargassum horneri (Akamoku), and Cystoseira hakodatensis (Uganomoku) were assayed for total phenolic content (TPC), fucoxanthin content, radical scavenging activities (DPPH, peroxyl radical, ABTS, and nitric oxide), and antioxidant activity in a liposome system. Among the solvents used for extraction, methanol was the most effective to extract total phenolics (TPC) from brown seaweeds. Among 5 kinds of brown seaweeds analyzed, methanol extract from C. hakodatensis was the best source for antioxidants. The high antioxidant activity of the extract was based not only on the high content of phenolics, but on the presence of fucoxanthin. No significant correlation (P > 0.05) was observed between TPC per gram extract with DPPH radical scavenging activity of the methanol extracts. These observed discrepancy would be due to structural variations in the phenolic compounds, and different levels of fucoxanthin in the extracts. The present study also demonstrated the synergy in the antioxidant activity of the combination of brown seaweed phenolics and fucoxanthin.