PJB-2018-663
Antibacterial antioxidant and phenolic fractions analysis of Caesalpinia crista seed coat extract and its different fractions
Lubna Mobin, Syed Asad Saeed, Rashida Ali, Shahina Naz and Syed Ghufran Saeed
Abstract
Methanolic crude extract from the seed coat of Caesalpinia crista was purified into different polyphenolic fractions. Solid Phase Extraction (SPE) was used for the purification of crude extract using C18 cartridges. Non-anthocyanin (fraction I) and anthocyanin (fraction II) are the two main fractions that were collected from crude extract and Fraction Ia (Phenolic acid), Fraction Ib (flavanols etc) and Ic (flavonols etc) are the three sub fractions collected from non-anthocyanin fractions. It was shown by the HPLC analysis of separated fractions that among the ten polyphenolic standards that were taken i.e. vanillic acid, syringic acid, coumaric acid, caffeic acid, delphinidin, myricetin, epicatechin, kaempferol, pelargonidin, cyanidin and their other derivatives were not the main constituent of the C. crista seed coat. Activity against the bacteria was determined against two Gram-positive and three Gram-negative bacteria by an agar well diffusion method. It was found that against a panel of bacteria the seed coat of C. crista was found active. Gram positive bacteria was more sensitive towards fraction Ic while fraction Ia was more active against gram negative bacteria. Antioxidant screening was carried out by using different methods such as reducing power, diphenyl-1-picrylhydrazyl and lipoxygenase assay. Study showed that the seed coat of C. crista has considerable antioxidant properties. Phenolic fractions’s order of antioxidant activity was in accordance to their whole flavonoid and phenolic contents (except of anthocyanin fraction) i.e. Non anthocyanin>flavonols>flavanol> phenolic acid. The significant (p<0.01) correlation was found between the antioxidant activity and the total phenolic content. Current study suggests that along with the content of polyphenols, the antioxidant and antimicrobial activities depend also on the structure of polyphenols. Moreover, the seed coat of C. Crista is a potential source of antibacterial and antioxidant compounds.
To Cite this article:
Mobin, L., S.A. Saeed, R. Ali, S. Naz and S.G. Saeed. 2021. Antibacterial antioxidant and phenolic fractions analysis of Caesalpinia crista seed coat extract and its different fractions. Pak. J. Bot., 53(2): DOI: http://dx.doi.org/10.30848/PJB2021-2(18)
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