Seaweed is more than the wrap that keeps rice together in sushi. Seaweed biomass is already used for a wide range of other products in food, including stabilising agents. Biorefineries with seaweed as feedstock are attracting worldwide interest and include low-volume, high value-added products and vice versa. Scientific research on bioactive compounds in seaweed usually takes place on just a few species and compounds. This paper reviews worldwide research on bioactive compounds, mainly of nine genera or species of seaweed, which are also available in European temperate Atlantic waters, i.e. Laminaria sp., Fucus sp., Ascophyllum nodosum, Chondrus crispus, Porphyra sp., Ulva sp., Sargassum sp., Gracilaria sp. and Palmaria palmata. In addition, Undaria pinnatifida is included in this review as this is globally one of the most commonly produced, investigated and available species. Fewer examples of other species abundant worldwide have also been included. This review will supply fundamental information for biorefineries in Atlantic Europe using seaweed as feedstock. Preliminary selection of one or several candidate seaweed species will be possible based on the summary tables and previous research described in this review. This applies either to the choice of high value-added bioactive products to be exploited in an available species or to the choice of seaweed species when a bioactive compound is desired. Data are presented in tables with species, effect and test organism (if present) with examples of uses to enhance comparisons. In addition, scientific experiments performed on seaweed used as animal feed are presented, and EU, US and Japanese legislation on functional foods is reviewed.

Bioactive compounds in seaweed: functional food applications and legislation

http://digital.csic.es/bitstream/10261/63862/4/Screening%20for%20Bioactive.pdf

Screening for Bioactive Compounds from Algae

Edible seaweeds are rich in bioactive antioxidants, soluble dietary fibers, proteins, minerals, vitamins, phytochemicals, and polyunsaturated fatty acids Although previously the seaweeds were only used as gelling and thickening agents in the food or pharmaceutical industries, recent researches have revealed their potential as complementary medicine The red, brown and green seaweeds have been shown to have therapeutic properties for health and disease management, such as anticancer, antiobesity, antidiabetic, antihypertensive, antihyperlipidemic, antioxidant, anticoagulant, anti-inflammatory, immunomodulatory, antiestrogenic, thyroid stimulating, neuroprotective, antiviral, antifungal, antibacterial and tissue healing properties in vivo Active compounds include sulphated polysaccharides, phlorotannins, carotenoids (eg fucoxanthin), minerals, peptides and sulfolipids, with proven benefits against degenerative metabolic diseases Their therapeutic modes of action and bioactive components have been meticulously studied by scientists and their reports are summarized in this review

Seaweeds: A sustainable functional food for complementary and alternative therapy

Six species of edible Irish seaweeds; Laminaria digitata, Laminaria saccharina, Himanthalia elongata, Palmaria palmata, Chondrus crispus and Enteromorpha spirulina were screened for potential bioactivity. Extraction of secondary metabolites was carried out using different solvents to determine antioxidant and antimicrobial properties of the dried extracts. The total phenolic contents of dried methanolic extracts were significantly different (p < 0.05). H. elongata exhibited highest phenolic content at 151.3 mg GAE/g of seaweed extract and also had the highest DPPH scavenging activity (p < 0.05) with a 50% inhibition (EC50) level at 0.125μg/ml of extract. H. elongata also had the highest total tannin and total flavonoid contents (p < 0.05) of 38.34 mg CE/g and 42.5 mg QE/g, respectively. Antimicrobial activity was determined using a microtitre method which allowed detection of bacterial growth inhibition at low levels. All methanolic seaweed extracts inhibited the food spoilage and food pathogenic bacteria tested; Listeria monocytogenes, Salmonella abony, Enterococcus faecalis and Pseudomonas aeruginosa, except C. crispus extracts. It was found that dried methanolic extracts of red and green seaweeds had significantly lower antimicrobial activity than the brown species; H. elongata had the highest antimicrobial activity with up to 100% inhibition. In the studied work, the antimicrobial activity of red and green seaweed extracts significantly increased when ethanol and acetone were used as extraction solvents (p < 0.05). Inhibition of E. faecalis with C. crispus extracts increased from 39.28 to 100% when ethanol and acetone were applied as solvents.

/pdf/an-assessment-of-the-antioxidant-and-antimicrobial-activity-17ovpvdza5.pdf

An Assessment of the Antioxidant and Antimicrobial Activity of Six Species of Edible Irish Seaweeds

Cancer remains one of the most lethal diseases worldwide. There is an urgent need for new drugs with novel modes of action and thus considerable research has been conducted for new anticancer drugs from natural sources, especially plants, microbes and marine organisms. Marine populations represent reservoirs of novel bioactive metabolites with diverse groups of chemical structures. This review highlights the impact of marine organisms, with particular emphasis on marine plants, algae, bacteria, actinomycetes, fungi, sponges and soft corals. Anti-cancer effects of marine natural products in in vitro and in vivo studies were first introduced; their activity in the prevention of tumor formation and the related compound-induced apoptosis and cytotoxicities were tackled. The possible molecular mechanisms behind the biological effects are also presented. The review highlights the diversity of marine organisms, novel chemical structures, and chemical property space. Finally, therapeutic strategies and the present use of marine-derived components, its future direction and limitations are discussed.

https://www.mdpi.com/1660-3397/17/9/491/pdf

Marine Natural Products : A Source of Novel Anticancer Drugs

Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds.

Tamarind seed is an underutilized byproduct of the tamarind pulp industry. Only a small portion of the seed, in the form of tamarind kernel powder (TKP), is used as a sizing material in the textile, paper, and jute industries. Though many applications of this seed are possible, there have been hardly any other uses for it including using it as an additive in food formulations. The excellent gelling cum adhesive characteristics of the decorticated seed powder can lead to several applications in food and pharmaceutical industries which are evident by the number of research papers as well as patent applications. This article thus focuses on the possibilities of using the seed in several food and non-food industries with particular reference to physical and engineering properties, hydration behavior, rheological properties, functional and nutritional characteristics, and the processing of the tamarind seed for wider applications.

Tamarind seed: properties, processing and utilization.

Ready-to-drink (RTD) tea is a popular beverage in many countries. Instability due to development of haze and formation of tea cream is the common problem faced in the production of RTD black tea beverages. Thus decreaming is an important step in the process to meet the cold stability requirements of the product. Enzymatic decreaming approaches overcome some of the disadvantages associated with other conventional decreaming methods such as cold water extraction, chill decreaming, chemical stabilization, and chemical solubilization. Enzyme treatments have been attempted at three stages of black tea processing, namely, enzymatic treatment to green tea and conversion to black tea, enzymatic treatment to black tea followed by extraction, and enzymatic clarification of extract. Tannase is the most commonly employed enzyme (tannin acyl hydrolase EC 3.1.1.20) aiming at improving cold water extractability/solubility and decreasing tea cream formation as well as improving the clarity. The major enzymatic methods proposed for processing black tea having a direct or indirect bearing on RTD tea production, have been discussed along with their relative advantages and limitations.

Application of Enzymes in the Production of RTD Black Tea Beverages: A Review

Studies were conducted on the selected quality attributes of rice flour obtained by dry and wet grinding methods. Raw and parboiled rice have been dry ground at a moisture content of 12%, while wet grinding is performed at 30%. The functional properties of ground samples and doughs made out of the flours were characterized. The damaged starch contents in the dry ground rice flour were 21.5 and 22.6% for raw and parboiled samples, respectively; whereas, these were only 8.7 and 9.5% for wet ground samples. The dry ground rice flour formed sticky dough having high stickiness values but it was less cohesive in nature compared to those of wet ground samples. The doughs made from wet ground rice were more adhesive than the dry ground samples; the former was suitable for forming extrusion processing for preparing various convenience foods like pasta and noodles.

https://www.tandfonline.com/doi/pdf/10.1080/10942910701657686

Chandini S. Kumar

Papers

Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds.

Tamarind seed: properties, processing and utilization.

Application of Enzymes in the Production of RTD Black Tea Beverages: A Review

A Comparison of Selected Quality Attributes of Flours: Effects of Dry and Wet Grinding Methods

Composition, Functionality and Potential Applications of Seaweed Lipids