Inhibition of fungal plant pathogens by seed proteins of  Harpullia cupanioides (Roxb.)

Abstract

Seed extracts of 50 plant species belonging to different families were evaluated for their ability to inhibit growth of Trichoderma viride in vitro. Of the various seed extracts, the seed extracts of Harpullia cupanioides (Roxb) belonging to Sapindaceae family exhibited very high antifungal activity. The seed extract of H. cupanioides strongly inhibited the growth of Rhizoctonia solani, Curvularia lunata, Colletotrichum musae and Alternaria alternata. Seed extract of H. cupanioides retained its antifungal activity even after heating at 100 °C for 10 min or autoclaving at 121 °C for 20 min. For partial purification of antifungal proteins, H. cupanioides seed extract was subjected to ammonium sulphate fractionation followed by gel filtration on Sephadex G-200 column. The fractions from sephadex G-200 were individually tested for their antifungal activity against T. viride. SDS-PAGE analysis of the fractions from Sephadex-G200 column indicated that the fractions with antifungal activity contained a 68-kDa band as well as other low molecular weight protein bands. The N-terminal amino acid sequence of the 68-kDa protein (13 residues) was determined by Edman degradation. However, comparison with sequences in the GenBank database (Swiss Prot) did not reveal any homology with known protein sequences.

Two Triterpenoid Saponins with alpha-glucosidase Inhibitory Activity from Harpullia pendula Seed Extract

“…1 Previous investigations carried out on these plants proved them to be rich in polyhydroxylated triterpenoid saponins. [2][3][4][5] This type of saponins was reported to exhibit antimicrobial, [6][7][8] molluscicidal, miracidicidal and cercaricidal activities 9 as well as cytotoxic and Haemolytic properties. 4 Harpullia pendula Planch known as tulipwood or tuliplance wood is a small to medium rainforest tree native to Australia.…”