The development of seaweed-derived bioactive compounds for use as prebiotics and nutraceuticals using enzyme technologies

This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This author accepted manuscript is made available following 12 month embargo from date of publication (Oct 2017) in accordance with the publisher’s archiving policyBackground Seaweeds are a large and diverse group of photosynthetic macro-algae found across the world's oceans. There is a growing recognition that they are important sources of bioactive compounds with a variety of biological activities that could potentially contribute to functional food and nutraceutical industries. Scope and approach The complex structure and distinctive components of seaweed cell walls, which differ significantly from terrestrial plants, presents a major challenge for the effective extraction of bioactive compounds from inside the cells. Enzyme technologies have been used to improve the extraction, hydrolysis, and structure modification efficiently with a high degree of environmental sustainability. This review critically analyses the advances, challenges, and future directions in applying enzyme technologies to improve the extraction and processing of bioactive compounds from seaweeds and their potential applications in functional foods and nutraceuticals. Key findings and conclusions Different enzymatic processes have been demonstrated to (1) assist the extraction by breaking down the seaweed cell walls, and (2) degrade or hydrolyse macromolecules including polysaccharides and proteins. These enzymatic processes improve the yield and recovery of bioactive compounds and enhance their biological properties with regard to prebiotic, antioxidant, ACE inhibitory, anti-inflammatory, and antiviral effects. Seaweed-derived bioactive compounds from these processes present significant new opportunities in developing novel food applications. The current food regulations and safety requirements for seaweeds and their products are addressed for commercial product development

Enzymatic Extraction of Fucoxanthin from Brown Seaweeds

Brown seaweeds contain a number of bioactive compounds. The xanthophyll, fucoxanthin, has in vivo efficacy against disorders such as type 2 diabetes, obesity and cancer. Organic solvents are traditionally employed to extract fucoxanthin, but carry a toxic chemical and environmental burden. The aim of this study was to optimise a fucoxanthin extraction method using enzymes, water, low-temperature dehydration and mechanical blending, to produce yields comparable to those achieved with an organic solvent (acetone). Response surface methodology was applied, using Fucus vesiculosus as a model species. A fucoxanthin yield of 0.657 mg g-1 (dry mass) was obtained from F. vesiculosus blade using the enzymatic method, equivalent to 94% of the acetone-extracted yield. Optimum extraction parameters were determined to be enzyme-to-water ratio 0.52%, seaweed-to-water ratio 5.37% and enzyme incubation time 3.05 h. These findings may be applied to the development of value-added nutraceutical products from seaweed

Influence of ohmic heating in the composition of extracts from Gracilaria vermiculophylla

Electric field-based technologies for extraction processes have been gaining importance due to sustainability concerns. This work aims to assess the potential of ohmic heating as an efficient and feasible tool for the extraction of different biocompounds from Gracilaria vermiculophylla and its effect on the extracts' composition. Different ratios of water/ethanol (0 to 75% ethanol, v/v) were used to target different families of biocompounds. The ohmic heating-based extraction was performed at 82 °C under electric field and frequency of 28 V/cm and 25 kHz, respectively. Conventional extractions without the presence of electric field were made keeping a temperature profile identical to the ohmic heating treatments, thus addressing the potential occurrence of electrical (non-thermal) effects. Extraction yields and extracts composition (content in polysaccharides, proteins, phenolic compounds and pigments) were evaluated. Further, as agar is the major commertially exploited compound from Gracilaria spp., the effect of ohmic heating on the extracted agar in terms of yield, carbohydrates' composition, monosaccharides profile, and gelling ability was also envisaged. Overall, significant differences in the extraction of each family of compounds between ohmic and conventional extractions were observed, being more pronounced at the best solvent for each compound (100% water for carbohydrates, 75:25 water/ethanol for proteins, 75:25 and 50:50 water/ethanol for phenolic compounds and 25:75 water/ethanol for pigments). Higher extraction yields were achieved for ohmic heating at 1 h, except for 100% water, probably indicating accelerated extraction kinetics promoted by the presence of electric field effects. Furthermore, the gelling ability of agar and the antioxidant activity were not impaired by the use of moderate electric fields. Therefore, ohmic heating is an interesting alternative, with reduced energy consumption and improved extraction performances, to recover functional ingredients or additives from seaweeds for the food industry.This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of project OH2O – PTDC/EQU/029145/2017 and the strategic funding of UID/BIO/04469/2019 unit, and by the European Fund for Regional Development (FEDER) and COMPETE 2020 – Competitiveness and Internationalization Operational Program under the scope the projects OH2O (POCI-01-0145-FEDER 029145) and VALORMAR – Full valorization of marine resources: po tential, technological innovation and new applications (call 10/SI/2016; reference: 24517). This work was also developed within the scope of the stratigic funding of CICECO-Aveiro Institute of Materials (UIDB/50011/2020 & UIDP/50011/2020), QOPNA (UID/QUI/00062/2019) and LAQV-REQUIMTE (UIDB/50006/2020), financed by national funds through the FCT/MEC and when appropriate co-financed by FEDER under the PT2020 Partnership Agreement. This work was also funded by national funds (OE), through FCT, I.P., within the scope of the frame work contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.info:eu-repo/semantics/publishedVersio

Gut Microbiota Modulation, Anti-Diabetic and Anti-Inflammatory Properties of Polyphenol Extract from Mung Bean Seed Coat (Vigna radiata L.)

The present study investigated the gut health, anti-diabetic, and anti-inflammatory activities of mung bean seed coat extract (MSE). MSE was obtained by pressurized liquid extraction (PLE) using 50% ethanol as the extracting solvent. After 24 h of in vitro human fecal fermentation, MSE exhibited higher productions of total short-chain fatty acids (SCFA) than those of the control group (CON) and other polyphenol-rich substrates, including gallic acid (GA) and vitexin (VIT) (p > 0.05), but still lower than the fructo-oligosaccharide (FOS). In 16S-rRNA next-generation sequencing, MSE regulated the composition of gut microbiota by stimulating the growth of the beneficial bacteria Enterococcus, Ruminococcus, Blautia, and Bacteroides and decreasing the growth of the potential pathogenic bacteria Escherichia-Shigella. Similarly, qPCR showed increased numbers of Bifidobacterium, Lactobacillus, Faecalibacterium prausnitzii, and Prevotella, compared with those of CON (p < 0.05). MSE also reduced reactive oxygen species and increased glucose uptake in insulin-resistant HepG2 cells dose-dependently. The anti-inflammatory activity of MSE was observed in LPS-stimulated THP-1 monocytes with the reduction of TNFα, IL-1β, IL-6, and IL-8 genes. The data demonstrated the potential applications of MSE as a dietary supplement with gut health benefits and its ability to mitigate diabetes and inflammatory-related diseases

Enzyme-assisted extraction of carbohydrates from the brown alga Ecklonia radiata: effect of enzyme type, pH and buffer on sugar yield and molecular weight profiles

Available online 15 July 2016The aim of this study was to understand the carbohydrate yield, composition, and molecular weight (MW) profiles of extracts from the brown alga Ecklonia radiata prepared using an enzyme-assisted extraction approach. The most significant effect on the total sugar yield was observed when comparing the use of salt-containing buffers (7.9–23.9 g × 100 g−1 dry weight (DW)) to pH-adjusted water (23.6–27.9 g × 100 g−1 DW), with the buffers significantly reducing the extraction efficiency in all instances. The inclusion of selected enzymes had little or no impact on total sugar yield, when compared with the corresponding solvent or buffer-only extractions. Marginal differences on total sugar yield were found when using different carbohydrate hydrolytic enzymes and proteases, and when changing pH in pH-adjusted water extractions. Both enzymes and pH influence sugar composition, and significantly affect MW profile of the polysaccharide fractions but in different ways. The acidic extraction at pH 4.5 yields lower MW components. Enzyme-assisted extraction reduced the MW of the extracted polysaccharides by 20–50% compared to pH-adjusted water only extractions.Suvimol Charoensiddhi, Andrew J. Lorbeer, Jelle Lahnstein, Vincent Bulone, Christopher M.M. Franco, Wei Zhan

Sequential extraction and characterization of fucoidans and alginates from Ecklonia radiata, Macrocystis pyrifera, Durvillaea potatorum, and Seirococcus axillaris

In a previous study, we optimized the acidic treatment of brown algae to facilitate the efficient sequential extraction of fucoidans and alginates, using a sample of the brown alga Ecklonia radiata. Here, we applied the optimized process to other brown algae feedstocks from South Australia, in order to assess their potential for valorization and to determine whether the process was effective when using different feedstocks. The starting materials included samples of Macrocystis pyrifera, Durvillaea potatorum, Seirococcus axillaris, and two more samples of E. radiata collected from different sites and at different periods. The initial feedstock sample (as used for optimization) was also included for comparison. In terms of product yields, the sequential process appeared to perform similarly for all feedstocks (30–40 % of total available fucoidans and 80–94 % of total available alginates), with the exception of Seirococcus axillaris (5.5 and 74 %, respectively). The remainder of the fucoidans either resisted extraction or were hydrolyzed by the acid treatment. The fucoidan extracts had sulfate contents of 10 to 30 % by weight and fucose contents of 12–30 % by weight and exhibited antioxidant potential, to which the presence of phlorotannins contributed. The quality of the alginates varied, with M. pyrifera yielding the most viscous (599 mPa s) and colorless alginates, while the alginates from S. axillaris had the lowest mannuronic to guluronic acid ratio (0.54), indicating the strongest gel-forming capability.Andrew J. Lorbeer, Suvimol Charoensiddhi, Jelle Lahnstein, Claire Lars, Christopher M.M. Franco, Vincent Bulone, Wei Zhan

Microbiome analysis of thai traditional fermented soybeans reveals short-chain fatty acid-associated bacterial taxa

Abstract Thua Nao is a Thai traditional fermented soybean food and low-cost protein supplement. This study aimed to evaluate the bacterial community in Thua Nao from northern Thailand and assess potentially active short-chain fatty acids (SCFAs)-related bacteria. Sixty-five Thua Nao consisting of 30 wet and 35 dried samples were collected from six provinces: Chiang Rai, Chiang Mai, Mae Hong Son, Lampang, Lamphun, and Phayao. Bacterial diversity was significantly higher in the wet samples than in the dried samples. The dominant phyla were Firmicutes (92.7%), Proteobacteria (6.7%), Actinobacteriota (0.42%), and Bacteroidota (0.26%). The genus Bacillus (67%) was the most represented in all samples. Lactobacillus, Enterococcus, and Globicatella were enriched in the wet samples. Assessment of the SCFA-microbiota relationships revealed that high butyrate and propionate concentrations were associated with an increased Clostridiales abundance, and high acetate concentrations were associated with an increased Weissella abundance. Wet products contained more SCFAs, including acetate (P = 2.8e−08), propionate (P = 0.0044), butyrate (P = 0.0021), and isovalerate (P = 0.017), than the dried products. These results provide insight into SCFA-microbiota associations in Thua Nao, which may enable the development of starter cultures for SCFA-enriched Thua Nao production

Polymeric Packaging Applications for Seafood Products: Packaging-Deterioration Relevance, Technology and Trends

Seafood is a highly economical product worldwide. Primary modes of deterioration include autolysis, oxidation of protein and lipids, formation of biogenic amines and melanosis, and microbial deterioration. These post-harvest losses can be properly handled if the appropriate packaging technology has been applied. Therefore, it is necessary for packaging deterioration relevance to be clearly understood. This review demonstrates recent polymeric packaging technology for seafood products. Relationship between packaging and quality deterioration, including microbial growth and chemical and biochemical reactions, are discussed. Recent technology and trends in the development of seafood packaging are demonstrated by recent research articles and patents. Development of functional polymers for active packaging is the largest area for seafood applications. Intelligent packaging, modified atmosphere packaging, thermal insulator cartons, as well as the method of removing a fishy aroma have been widely developed and patented to solve the specific and comprehensive quality issues in seafood products. Many active antioxidant and antimicrobial compounds have been found and successfully incorporated with polymers to preserve the quality and monitor the fish freshness. A thermal insulator has also been developed for seafood packaging to preserve its freshness and avoid deterioration by microbial growth and enzymatic activity. Moreover, the enhanced biodegradable tray is also innovative as a single or bulk fish container for marketing and distribution. Accordingly, this review shows emerging polymeric packaging technology for seafood products and the relevance between packaging and seafood qualities