GC/MS Analysis, Cytotoxicity, and Antiviral Activities of Annona glabra Hexane Extract Supported by In Silico Study

Abstract: Annona glabra Linn is employed in conventional medicine to treat a number of human
disorders, including cancer and viruses. In the present investigation, the significant phytochemical
components of Annona glabra hexane extract were identified using gas chromatography–mass
spectrometry (GC-MS) analysis. Three major compounds were identified in the hexane extract: tritriacontane
(30.23%), 13, 17-dimethyl-tritriacontane (22.44%), and limonene (18.97%). MTT assay was
used to assess the cytotoxicity of the extract on six human cancer cell lines including liver (HepG-2),
pancreas (PANC-1), lung (A-549), breast (MCF-7, HTB-22), prostate (PC-3), and colon (CACO-2,
ATB-37). The extract exhibited significant cytotoxic activity against both CACO-2 and A-549 cancer
cell lines (IC50 = 47  0.74 g/mL and 56.82  0.92 g/mL) in comparison with doxorubicin
(IC50 = 31.91  0.81 g/mL and 23.39  0.43 g/mL) and of SI of 3.8 and 3.1, respectively. It also
induced moderate-to-weak activities against the other cancerous cell lines: PC-3, PANC-1, MCF-7,
and HepG-2 (IC50 = 81.86  3.26, 57.34  0.77, 80.31  4.13, and 57.01  0.85 g/mL) in comparison
to doxorubicin (IC50 = 32.9  1.74, 19.07  0.2, 15.48  0.84 and 5.4  0.22 g/mL, respectively)
and SI of 2.2, 3.1, 2.2, and 3.1, respectively. In vitro anti-HSV1 (Herpes simplex 1 virus) and HAV
(Hepatitis A virus) activity was evaluated using MTT colorimetric assay with three different protocols
to test protective, anti-replicative, and anti-infective antiviral activities, and three separate
replications of each experiment were conducted. The plant extract showed promising protective
and virucidal activity against HSV1 with no significant difference with acyclovir (79.55  1.67 vs.
68.44  7.62 and 70.91  7.02 vs. 83.76  5.67), while it showed mild protective antiviral activity
against HAV (48.08 3.46) with no significant difference vs. acyclovir (36.89  6.61). The selected
main compounds were examined for their bioactivity through in silico molecular docking, which
exhibited that limonene could possess the strongest antiviral properties. These findings support
Annona glabra’s conventional use, which is an effective source of antiviral and anticancer substances
that could be used in pharmaceuticals.