Chemical profiling and biological activity of Cassia abbreviata Oliv.

Abstract

We describe the phytochemical profile, antimicrobial and insecticidal activity of the aerial parts (mature leaves, flowers, pulp, seeds) of Cassia abbreviata Oliv. The extracts were prepared by the maceration technique with methanol, petroleum ether and dichloromethane. The antimicrobial potential of the extracts was evaluated by the microdilution method. The insecticidal activity of the extracts was tested against the first instar larvae of Plutella xylostella Linnaeus. Laboratory trials demonstrated that the dichloromethane seed extracts of the plant exhibited promising antibacterial activity against Proteus mirabilis (ATCC 12,453) at 1.56 mg/ml. The dichloromethane pulp extracts elicited the highest larval mortality (86.67±5.77%) and antifeedant activity (83.30±0.59%) in P. xylostella at 50 mg/ml after 24 h of larval feeding. Pupae and adults emerged from treated larvae showed several morphological abnormalities. The dichloromethane seed and pulp extracts of C. abbreviata were subjected to GC-MS analysis in view of their highest antimicrobial and insecticidal activity. The current investigation reports the presence of Hexadecanoic acid, 2‑hydroxy-1-(hydroxymethyl) ethyl ester (8.90%) and Phenol, 2,4-bis(1,1-dimethylethyl) (6.34%) as the major compounds in the dichloromethane pulp extracts. The predominant compound in the dichloromethane seed extracts is 1,2-Benzenedicarboxylic acid, bis (2-ethylhexyl) ester (70.20%). The strong antimicrobial and insecticidal potential of C. abbreviata seed and pulp extracts may be due to the major phytoconstituents identified through GC-MS studies or through synergistic interactions of the major and minor compounds. The findings suggest that the tested extracts can be considered as potential candidates in the search for alternative sources of antimicrobial agents and biopesticides.