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Seaweeds are an excellent source of bioactive compounds, and therefore the use of sustainable and food compatible extraction methods such as enzyme-assisted (EAE) and ultrasound-assisted extraction were applied on Sargassum muticum, Osmundea pinnatifida, and Codium tomentosum. Extracts were evaluated for proximate characterization and biological properties. Higher extraction yields were observed for C. tomentosum EAE (48-62%; p < 0.05 for Cellulase and Viscozyme), followed by O. pinnatifida (49-55%; p < 0.05 except Alcalase) and S. muticum (26-31%; p < 0.05). S. muticum extracts presented the highest nitrogen (25 ± 2 mg/glyoph extract) and total phenolics (261 ± 37 μgcatechol equiv/glyoph extract) contents, whereas higher sugars (78 ± 14 mgglucose equiv/glyoph extract) including sulfated polysaccharide (44 ± 8 mgNa2SO4 acid/glyoph extract) contents characterized O. pinnatifida extracts. A higher effect on hydroxyl-radical scavenging activity (35-50%) was observed for all extracts, whereas S. muticum Alcalase and C. tomentosum Cellulase extracts exhibited higher prebiotic activity than fructooligosaccharides. O. pinnatifida and C. tomentosum EAE showed inhibitory potential against α-glucosidase (38-49%).

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a b s t r a c tThe survival rates of Lactobacilus acidophilus Ki, Lactobacillus paracasei L26 and Bifidobacterium animalis BB-12 were studied after whey protein microencapsulation via spray-drying, with or without L-cysteineHCl, and storage up to 6 months at 5 C and 22 C, with variation in relative air humidity and oxygen levels. Lb. paracasei L26 was the least susceptible to storage conditions: above 10 6 cfu g À1 were recorded by 180 d at 22 C, irrespective of relative humidity, and the presence/absence of oxygen and L-cysteine. Higher relative humidity, higher temperature and longer storage periods were deleterious to survival of both B. animalis BB-12 and Lb. acidophilus Ki; the effect of L-cysteine-HCl was dependent on the probiotic strain. The effect of overhead oxygen was not significant upon any probiotic strain studied. Whey protein microcapsules containing L-cysteine-HCl protected probiotic cultures from simulated gastrointestinal conditions.

a b s t r a c tExtracts with prebiotic activity or bioactive compounds from natural sources such as seaweeds or mushrooms, combining a broad spectrum of biological properties, may offer great potential for their use as functional ingredients enabling intestinal microbiota modulation. In this context, selected enzymatic extracts from Sargassum muticum, Osmundea pinnatifida and Pholiota nameko were evaluated in vitro. Faecal fermentations were conducted anaerobically under controlled temperature and pH over 24 h. Enzymatic extracts of Ph. nameko and of O. pinnatifida at 1% (w/v), lead to increases in Bifidobacterium spp. after 6 h of fermentation in comparison to negative control, suggesting a stimulatory effect. No significant changes over 24 h were observed of Lactobacillus spp. In particular, the Ph. nameko extract obtained with Flavourzyme not only stimulated growth and/or activity of Bifidobacterium spp. but also led to a decrease of Clostridium histolyticum group upon 24 h, thus potentially benefiting colonic health. Higher percentages of this extract (2 and 3%) impaired a C. histolyticum reduction confirming this selective action and prebiotic potential. Differences in short chain fatty acids (SCFA) and lactic acid production between the four extracts may indicate a potential relationship between their physico-chemical properties, which differ in composition and structures, and modulation of gut bacterial species.