Total polyphenolic compounds, total flavonoids, GC-MS analysis of volatile constituents, evaluation of antioxidant and antimicrobial activities of Prunus dulcis nuts

Abstract

Prunus dulcis has been known as a source of nutrients in many traditional foods and as a source of important biologically active compounds in traditional medicines. The present study describes the determination of total polyphenolic compounds, total flavonoids and GC-MS analysis of hexane and chloroform fractions of 70% ethanol extract of whole almond shelled seed. Antioxidant and antimicrobial activities of various extracts of the nuts were evaluated. Folin-Ciocalteau procedure resulted in total polyphenolic compounds as 0.008 mg (gallic acid equivalents)/mg of the dried extract and amount of total flavonoids contents yielded were 0.001 mg (quercetin equivalents)/mg of the nuts dried extracts. GC-MS analysis of the hexane and chloroform fractions yielded a number of volatile constituents, resulting in highest amounts of 6-Octadecenoic acid and 1,1,3,3-Tetramethyl cyclopentane as 37.52% and 24.54% in hexane and chloroform fractions respectively. Antioxidant activity using the DPPH radical scavenging assay resulted in very low activity in all the extracts. Only n-butanol extract showed mild activity against the gram negative E. coli with inhibition zone diameter 8 mm while rest of samples did not show any activity against any microbial strains under study.