Potential of benthic diatoms Achnanthes longipes, Amphora coffeaeformis and Navicula sp. as antioxidant sources
2006
Affan, A. | Karawita, R. | Jeon, Y.J. | Lee, J.B., Cheju National Univ., Jeju 690-756 (Korea). Dept. of Oceanography
Recently, interest in plant-derived food additives has developed, mainly because synthetic antioxidants suffer from several disadvantages. In the present study, different organic fractions from solvent partition of 80% methanol extracts and enzymatic extracts from five proteases and five carbohydrases from benthic diatoms - Achnanthes longipes, Navicula sp. and Amphora coffeaeformis - were assessed for their antioxidant activity. Among the organic fractions tested, the n-hexane (80.4%) and 80% methanol extracts (76.6%) of A. longipes, chloroform (63.2%) of Navicula sp. and n-hexane (67.4%) of A. coffeaeformis, were effective in DPPH radical scavenging. The chloroform (53.4%) fractions and n-hexane (53.1%) fractions of A. longipes (53.4% and 53.1%) exhibited higher activities of H2O2. The n-hexane fraction of A. longipes was highest in presenting hydroxyl radical scavenging activity and NO inhibition activity (56.5% and 75.6% respectively). The aqueous residue of A. coffeaeformis (75.6%) showed the highest metal chelating effect. Chloroform and ethyl acetate fractions of all diatoms exhibited significant antioxidant activity in linoleic acid peroxidation. Among enzymatic extracts, the Neutrase extract of A. coffeaeformis exhibited the highest effect in DPPH radical scavenging. Flavozyme (48.7%), Viscozyme (47.4%) and Celluclast (45.7%) extracts of Navicula sp. exhibited higher O2 radical scavenging activity. The Viscozyme extract of A.longipes (41.2%) possessed the highest effect in hydroxyl radical scavenging. On the other hand, termamyl (89.3%) and protamax (88.8%) had strong metal chelating activity. In linoleic acid peroxidation, Termamyl and Kojizyme extracts of A. longipes, AMG and Termamyl of Navicula sp., and Kojizyme of A. coffeaeformis showed significant effect. These data suggest that Jeju benthic diatoms are rich in hydrophobic and hydrophilic antioxidative compounds with different antioxidative properties, which can be applied in the food and pharmaceutical industries.
显示更多 [+] 显示较少 [-]