Abstract
Polysaccharides from Grateloupia livida (Harv.) Yamada (GL) were extracted by a heating circumfluence method. Single-factor experiments were performed for the three parameters: extraction time (X1), extraction temperature (X2) and the ratio of water to raw material (X3) and their test range. From preliminary experimental results, one type of the response surface methodology, the Box-Behnken design was applied for the optimizing polysaccharide extraction conditions. The experimental data obtained were fitted to a second-order polynomial equation. The optimal conditions were extraction time 5 h, extraction temperature 100 °C and ratio of water to raw material 70 mL/g. Under these conditions, the experimental yield was 39.22% ± 0.09%, which well matched the predicted value (39.25%), with 0.9774 coefficient of determination (R2). GL polysaccharides had scavenging activities for DPPH and hydroxyl radicals in vitro. The scavenging rates for both radicals peaked at 20 mg/mL GL concentration. However, the positive standard, VC (ascorbic acid), possessed stronger antioxidant activities than GL polysaccharides. Furthermore, the anticancer activity of GL polysaccharides on HepG2 cell proliferation increased dose- and time-dependently, but the positive standard, 5-fluorouracil (5-fu, showed more significant anticancer activity in this study. Overall, GL polysaccharides may have potential applications in the medical and food industries.
Highlights
Marine algae are classified by their colors, mainly red, green, and brown algae
The three factors were effective for the yield of Grateloupia livida (Harv.) Yamada (GL) polysaccharides
The effect of extraction time on the yield of GL polysaccharides was investigated with extraction time 3 to 7 h (Figure 1A), with other extraction parameters fixed, such as an extraction temperature of
Summary
Marine algae are classified by their colors, mainly red, green, and brown algae. The red algae have a special red color because of the algae pigments and accessory pigments, and different living water layers lead to different ratios of accessory pigments, so different species of red algae have different colors, ranging from yellowish-red to purplish-red [1]. G. livida (Harv.) Yamada (GL), a red algae belonging to Rhodophyta, Rhodophyceae, Gigartinales, Halymeniaceae, is mainly distributed in the coastal warm temperate zone [8]. It is an edible and medicinal seaweed, usually used for treating sore throat, stomachache, ascariasis and seaworm infections and dysentery [9]. According to our preliminary research, we separated the ethanol extract, petroleum ether, ethyl acetate, n-butyl alcohol and aqueous fractions from GL and discovered antioxidant, antibacterial and antischistosomal bioactivities [8] In this experiment, we studied the extraction of aqueous fractions, or polysaccharides. We evaluated the scavenging and anticancer activities of GL polysaccharides with the aim of exploitation for medicines and foods
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
