Assessment of chemically characterized nanoencapuslated Ocimum sanctum essential oil against aflatoxigenic fungi contaminating herbal raw materials and its novel mode of action as methyglyoxal inhibitor

Abstract

The study reports industrial significance of chemically characterized nanoencapuslated Ocimum sanctum essential oil (OSEO) against fungi contaminating herbal raw materials and aflatoxin B 1 secretion. The chitosan encapsulated OSEO exhibited enhanced antifungal and antiaflatoxigenic potential as compared to unencapsulated OSEO. The nanoencapsulated OSEO reduced the ergosterol content and enhanced the leakage of vital cellular ions along with the loss of 260 and 280 nm absorbing material suggesting fungal plasma membrane as action site. The nanoencapsulated OSEO also reduced the methylglyoxal content, the aflatoxin inducing substrate. In addition, the OSEO nanoemulsion possessed promising antioxidant potential. The nanoemulsion was characterized through SEM, FTIR and XRD analysis. This is the first report on assessment of OSEO loaded novel chitosan nanoemulsion against aflatoxin B 1 contamination. The study recommends application of the encapsulated OSEO to extend the shelf life of stored herbal raw materials and the findings also lead towards the development of aflatoxin and methylglyoxal resistant medicinal plants through green transgenics. © 2019 Elsevier B.V.