•Carotenoid and phenolics significantly correlated (p<0.05) to antioxidant activities.•Fucoxanthin and gallic acid were the lead compounds responsible for antioxidant activities.•Chaetoceros ...calcitrans and Isochrysis galbana had higher activities than the rest.
Natural antioxidants from sustainable sources are favoured to accommodate worldwide antioxidant demand. In addition to bioprospecting for natural and sustainable antioxidant sources, this study aimed to investigate the relationship between the bioactives (i.e. carotenoid and phenolic acids) and the antioxidant capacities in fucoxanthin‐producing algae. Total carotenoid, phenolic acid, fucoxanthin contents and fatty acid profile of six species of algae (five microalgae and one macroalga) were quantified followed by bioactivity evaluation using four antioxidant assays. Chaetoceros calcitrans and Isochrysis galbana displayed the highest antioxidant activity, followed by Odontella sinensis and Skeletonema costatum which showed moderate bioactivities. Phaeodactylum tricornutum and Saccharina japonica exhibited the least antioxidant activities amongst the algae species examined. Pearson correlation and multiple linear regression showed that both carotenoids and phenolic acids were significantly correlated (p<0.05) with the antioxidant activities, indicating the influence of these bioactives on the algal antioxidant capacities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
To compare the in vitro antioxidant capacity of a diatom, Chaetoceros calcitrans (C. calcitrans) extracted using six types of solvents.
Each extract was evaluated in terms of extraction yield, total ...carotenoid, fucoxanthin content, total phenolic and antioxidant capacities (DPPH and ABTS+ scavenging activity and iron chelating activity).
The methanol extract exhibited the highest yield (22.71 ± 0.96) g/100 g dry weight (DW), total carotenoid (4.46 ± 0.36) mg/g DW, total phenolic (2.49 ± 0.08) mg gallic acid equivalents/g DW and second highest fucoxanthin content (2.08 ± 0.03) mg fucoxanthin/g DW as compared to other solvent extracts. Methanolic extract also exhibited significantly higher (P < 0.05) scavenging (DPPH, ABTS+) and iron chelating activities.
Methanol was the recommended solvent for the production of antioxidant rich extract from C. calcitrans. Both carotenoids and phenolic acids were found to be positively correlated to the antioxidant capacities of C. calcitrans. Lead bioactives confirmed by subsequent high performance liquid chromatography studies were fucoxanthin, gallic acid and protocatechuic acid.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Jellyfish is an emerging aquaculture species, farmed for Oriental cuisines and nutraceutical ingredients. This study aimed to examine antioxidative and antimicrobial potentials of various fractions ...of the jellyfish, Acromitus hardenbergi. The bell and oral arms of the jellyfish were sequentially extracted with petroleum ether (PE), dichloromethane (DCM), chloroform (CHCl3), methanol (MeOH), and water (H2O) to extract its bioactive in an increasing polarity gradient. Test fractions were assayed for antiradical activities using electron spin resonance spectrometry, β-carotene-linoleate model and Folin-Ciocalteu assay; and antimicrobial activity against 2 Gram-negative bacteria, 4 Gram-positive bacteria and 2 fungal species using the disc diffusion assay. All fractions were also subjected to Fourier Transform Infrared (FTIR) analysis to identify types of functional groups present. It was found that the hydrophilic extracts (H2O fractions) possessed the most effective radical scavenging activity (p < 0.05) while the lipophilic extracts (PE fractions) the most active antimicrobial activity, especially against Gram-positive bacteria (p < 0.05). Total oxidation substrates content was found to be highest in the PE fractions of jellyfish bell and oral arms (p < 0.05). FTIR data showed that the H2O and MeOH fractions contains similar functional groups including -OH, -C=O, -N-H and -S=O groups, while the PE, DCM, and CHCl3 fractions, the -CH3, -COOH groups. This study showed that A. hardenbergi contains antioxidants and antimicrobials, thereby supporting the traditional claim of the jellyfish as an anti-aging and health-promoting functional food. Bioassay-guided fractionation approach serves as a critical milestone for the strategic screening, purification, and elucidation of therapeutically significant actives from jellyfish.
Data in this article illustrate representative fucoxanthin chromatograms of a microalga, Chaetoceros calcitrans; a macroalga, Saccharina japonica and; a pure fucoxanthin standard. High performance ...liquid chromatography (HPLC) eluted fucoxanthin at the 7.008±0.024thmin. This data article refers to the research article ‘‘Antioxidant capacities of fucoxanthin-producing algae as influenced by their carotenoid and phenolic contents’’ Foo et al. 1; where a more comprehensive data interpretation and analysis is explained.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fucoxanthin is the major carotenoid produced by diatoms and shown to exhibit potent anti-obesity and anti-cancer activities. This study presents a simple protocol for the preparation of ...fucoxanthin-rich fraction (FxRF) with high antioxidative properties from a selected marine diatom, Chaetoceros calcitrans. Fucoxanthin concentrates were prepared from crude methanolic extract (CME) with liquid–liquid partitioning of three types of solvent systems (i.e. diethyl ether–water, dichloromethane–water and ethyl acetate–water), followed by comparative antioxidant evaluation. Dichloromethane fraction (DCMF) was found to contain significantly higher (p<0.05) level of carotenoid (7.13±0.01mg·g−1DW) and fucoxanthin (5.25±0.03mgFX·g−1DW) contents accompanied with elevated (p<0.05) antioxidant activities (DPPH and ABTS+ radical scavenging, and beta carotene bleaching assays) as compared to other tested fractions. This study showed that FxRF with enhanced antioxidant properties could be effectively produced and concentrated through the DCM–H2O partition of CME.
•Production of fucoxanthin-rich fraction (FxRF) from a diatom was demonstrated.•Dichloromethane–water fractionation was the best system to produce FxRF.•The FxRF exhibited a higher antioxidant activity than the crude extract.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Jellyfish is an emerging aquaculture species, farmed for Oriental cuisines and nutraceutical ingredients. This study aimed to examine antioxidative and antimicrobial potentials of various fractions ...of the jellyfish, Acromitus hardenbergi. The bell and oral arms of the jellyfish were sequentially extracted with petroleum ether (PE), dichloromethane (DCM), chloroform (CHCl3), methanol (MeOH), and water (H2O) to extract its bioactive in an increasing polarity gradient. Test fractions were assayed for antiradical activities using electron spin resonance spectrometry, β-carotene-linoleate model and Folin-Ciocalteu assay; and antimicrobial activity against 2 Gram-negative bacteria, 4 Gram-positive bacteria and 2 fungal species using the disc diffusion assay. All fractions were also subjected to Fourier Transform Infrared (FTIR) analysis to identify types of functional groups present. It was found that the hydrophilic extracts (H2O fractions) possessed the most effective radical scavenging activity (p < 0.05) while the lipophilic extracts (PE fractions) the most active antimicrobial activity, especially against Gram-positive bacteria (p < 0.05). Total oxidation substrates content was found to be highest in the PE fractions of jellyfish bell and oral arms (p < 0.05). FTIR data showed that the H2O and MeOH fractions contains similar functional groups including -OH, -C=O, -N-H and -S=O groups, while the PE, DCM, and CHCl3 fractions, the -CH3, -COOH groups. This study showed that A. hardenbergi contains antioxidants and antimicrobials, thereby supporting the traditional claim of the jellyfish as an anti-aging and health-promoting functional food. Bioassay-guided fractionation approach serves as a critical milestone for the strategic screening, purification, and elucidation of therapeutically significant actives from jellyfish.
Objective: To compare the in vitro antioxidant capacity of a diatom, Chaetoceros calcitrans(C. calcitrans) extracted using six types of solvents.Methods: Each extract was evaluated in terms of ...extraction yield, total carotenoid,fucoxanthin content, total phenolic and antioxidant capacities(DPPH and ABTS +scavenging activity and iron chelating activity).Results: The methanol extract exhibited the highest yield (22.71 ± 0.96) g/100 g dry weight(DW), total carotenoid (4.46 ± 0.36) mg/g DW, total phenolic (2.49 ± 0.08) mg gallic acid equivalents/g DW and second highest fucoxanthin content (2.08 ± 0.03) mg fucoxanthin/g DW as compared to other solvent extracts. Methanolic extract also exhibited significantly higher(P < 0.05) scavenging(DPPH, ABTS +) and iron chelating activities.Conclusions: Methanol was the recommended solvent for the production of antioxidant rich extract from C. calcitrans. Both carotenoids and phenolic acids were found to be positively correlated to the antioxidant capacities of C. calcitrans. Lead bioactives confirmed by subsequent high performance liquid chromatography studies were fucoxanthin, gallic acid and protocatechuic acid.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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