Dr. Aditi KunduSOURABH SUMANT-111672024-09-102024-09-102023https://krishikosh.egranth.ac.in/handle/1/5810214231Litsea glutinosa is an evergreen tree, belong to Lauraceae family, widely distributed in India, Southern China, Malaysia, Australia and the Western Pacific islands. Diverse biofunctional properties of the plant are attributed to its valuable phyto-components. Sequential extraction using various organic solvents through Conventional Solid Liquid Extraction (CSLE) resulted highest yield of methanolic extract (6.74%), followed by CHCl3 (3.87%) extract and EtOAc (3.12%) extract. Extracts were evaluated in vitro against selected pathogenic fungi, Aspergillus flavus, A. parasiticus, and Penicillium expansum using poison food technique, highlighting maximum inhibitory action of CHCl3 extract against P. expansum (EC50 85.3 μg/mL) and A. parasiticus (EC50 129.1 μg/mL). However, EtOAc soluble fraction exhibited substantial mycelial growth inhibitory action against A. parasiticus (EC50 151.5 μg/mL). While, inverted plate antifungal assay revealed moderate effectiveness of CHCl3 extract against P. expansum (EC50 493.1 μg/mL), suggesting potential antifungal effect due to non-volatile components of the extract. Monoterpene dl-limonene (58.40%) rich L. cubeba exhibited highest efficacy against A. parasiticus 6365 (EC50 253.3 μg/mL). A comparative analysis of four extraction techniques namely, CSLE, Ultrasonic Assisted Extraction (UAE), Microwave Assisted Extraction (MAE), and High-Speed Homogenization displayed UAE as the most efficient method. Therefore, UAE parameters were optimized to yield maximum CHCl3 soluble fractions using Response Surface Methodology (RSM) design. RSM results showed an impressive extraction yield of 582.15 mg/ 5 g sample, employing solvent to solute ratio of 54.43 mL/5g, employing power of 58.26 W and extraction time of 19.07 min. Further, superiority of extraction efficiency of UAE over CSLE was also demonstrated by SEM microstructural analysis of the extracted samples, claiming more disintegration and rupture of the cell matrix. Fatty acid composition analysis of L. glutinosa bark resulted octadecanoic acid (11.69%) and 9,12-octadecadienoic acid (11.45%) as predominant. Untargeted phytochemical analysis using UPLC-QTOF-ESI-MS/MS revealed tentative identification of forty compounds from CHCl3 extract comprising, astragalin (448.0997), boldine (329.1618), litseaglutine A (312.1229), lauroscholtzine (342.1695), obtusilactone B(333.2435), akolactone A (293.2489), litseakolide A (309.2062), obtusilactone A (309.2438), akolactone B (289.2172), litsealactone B (279.1964), litseakolide B (307.2269) litsine A (422.1595) and liseanolide (283.2278) etc. Likewise, analysis of hexane, EtOAc and methanolic extracts based on their accurate mass resulted tentative identification of nineteen, twenty-six and thirty-eight phytocompounds, respectively. The effect of CHCl3 extract on the treated fungi resulted reduction of cell wall ergosterol content 98.19% in P. expansum at 3000 μg/mL concentration. Molecular docking studies of the identified major compounds (ligands) and cyt P450 sterol 1,4 α-demethylase (target protein, responsible for ergosterol biosynthesis) indicated litsealactone B as most prominent component due to its low distance conventional H-bonds and hydrophobic π-alkyl interactions.EnglishThesis