Isolation and antioxidative properties of phenolics-saponins rich fraction from defatted rice bran   总被引：1，自引：0，他引：1  

Kim Wei Chan  Nicholas M.H. Khong  Shahid Iqbal  Maznah Ismail 《Journal of Cereal Science》2013

The study presents a protocol for the preparation of phenolics-saponins rich fraction (PSRF), a new active nutraceutical from defatted rice bran followed by the determination of its antioxidant properties. PSRF was prepared by employing a simple alcoholic fractionation procedure on the crude alcoholic extract (CAE) of defatted rice bran. PSRF was found to be significantly higher in the contents of total phenolic, saponin, and steroidal saponin than CAE and its counterpart, aqueous fraction (AqF) (p < 0.05). Except for iron chelating activity, PSRF exhibited notably higher activity than CAE and AqF in all antioxidant activity assays performed (p < 0.05). HPLC-DAD analysis revealed that PSRF contained substantially higher amounts of gallic acid, 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, and ferulic acid than CAE and AqF (p < 0.05). In conclusion, alcoholic fractionation of CAE simultaneously concentrated the phenolic compounds and saponins into PSRF, thus contributed to its higher antioxidant activity. Due to its elevated antioxidant properties, PSRF may be recommended for investigation as an active ingredient in the nutraceutical, functional food, and natural food preservative formulations. This is also the first report suggesting defatted rice bran as a potential and sustainable source of saponins.  相似文献   

Biomass,proximate biochemical composition and fatty acid profiles associated with the growth phase of Chlorella salina Butcher and Isochrysis maritima Billard and Gayral isolated from the coastal waters of Penang,Malaysia     

Syazwina  S. Siti  Basri  E. Mohammad  Maznah  W. O. Wan 《Aquaculture International》2022,30(2):899-918

Choosing the right algae with the relevant properties and optimal harvest time for specific culture conditions and products is essential. As such, biomass, biochemical composition and fatty acid (FA) profile at different growth stages of locally isolated strains, suitable for aquaculture, Chlorella salina and Isochrysis maritima, were determined. Biomass and moisture content of both species were affected by the growth phase. A particular accumulation trend of proximate biochemical compounds was observed in these two strains. Protein content decreased whereby, as culture aged, more carbohydrate and lipid accumulated in C. salina and I. maritima, respectively. Variations in FA profile were exhibited in C. salina where PUFA was the highest, followed by SFA and MUFA throughout the growth phases. I. maritima had the highest SFA content, followed by PUFA and MUFA during the exponential phase. The essential PUFAs in C. salina were linoleic acid (LA) and α-linolenic acid (ALA) with a low occurrence of γ-linolenic acid (GLA; 0.49–0.78%) and docosahexaenoic acid (DHA; 0.21–0.45%). I. maritima recorded relatively high ALA (4.73–6.71%), GLA (5.05–7.80%) and DHA (5.15–7.02%) with minor presence of arachidonic acid (ARA; 0.45–0.59%) and eicosapentaenoic acid (EPA; 0.43–0.58%). Both C. salina and I. maritima are suitable for aquaculture feeds, but I. maritima was more superior by having EPA and higher DHA in their cells. Harvesting regime at a specific phase must be taken into account to achieve maximum yields of a target compound; thus, for feeding purpose, harvesting both strains at stationary phase is recommended as better PUFA compositions were obtained.

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