AUTHOR=Singh Bijendra Kumar , Chaudhari Anand Kumar , Das Somenath , Tiwari Shikha , Maurya Akash , Singh Vipin Kumar , Dubey Nawal Kishore 

TITLE=Chitosan encompassed Aniba rosaeodora essential oil as innovative green candidate for antifungal and antiaflatoxigenic activity in millets with emphasis on cellular and its mode of action

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.970670

DOI=10.3389/fmicb.2022.970670

ISSN=1664-302X

ABSTRACT=<p>The present study demonstrates first time investigation on encapsulation of <italic>Aniba rosaeodora</italic> essential oil into chitosan nanoemulsion (AREO-CsNe) with the aim of improvement of its antifungal, and aflatoxin B<sub>1</sub> (AFB<sub>1</sub>) inhibitory performance in real food system. The GC–MS analysis of AREO revealed the presence of linalool (81.46%) as a major component. The successful encapsulation of EO into CsNe was confirmed through SEM, FTIR, and XRD analysis. The <italic>in-vitro</italic> release study showed the controlled release of AREO. AREO-CsNe caused complete inhibition of <italic>Aspergillus flavus</italic> (AFLHPSi-1) growth and AFB<sub>1</sub> production at 0.8 and 0.6 μl/ml, respectively, which was far better than AREO (1.4 and 1.2 μl/ml, respectively). Impairment of ergosterol biosynthesis coupled with enhancement of cellular materials leakage confirmed plasma membrane as the possible antifungal target of both AREO and AREO-CsNe. Significant inhibition of methylglyoxal (AFB<sub>1</sub> inducer) synthesis in AFLHPSi-1 cells by AREO and AREO-CsNe confirmed their novel antiaflatoxigenic mode of action. <italic>In-silico</italic> molecular docking studies revealed effective interaction of linalool with Ver-1 and Omt-A proteins, leading to inhibition of AFB<sub>1</sub> biosynthesis. Further, AREO-CsNe showed enhanced antioxidant activity with IC<sub>50</sub> values 3.792 and 1.706 μl/ml against DPPH<sup>•</sup> and ABTS<sup>•+</sup> radicals, respectively. In addition, AREO-CsNe caused 100% protection of stored millets (<italic>Setaria italica</italic> seeds) from AFB<sub>1</sub> contamination and lipid peroxidation over a period of 1 year without compromising its sensory properties and exhibited high safety profile with LD<sub>50</sub> value 9538.742 μl/kg body weight. Based on enhanced performance of AREO-CsNe over AREO, it can be recommended as a novel substitute of synthetic preservative for preservation of stored millets.</p>