Annonareticulate (Mart.), Lablab purpureus (L.) Sweet, Murrayakoenigii (L.) Spreng, Moringaoleifera (Lam.), Hibiscussabdariffa (L.) and Euphorbiahirta (L.) are most commonly used medicinal plants by the traditional healers of Karbi Anglong district of Assam, India against different human ailments including cancer suspected cases. The proposed study includes field survey related to ethnomedicinal aspects of medicinal plants, phytochemical analysis, and evaluation of their cytostatic potential with the possible mode of action against Dalton's lymphoma (DL) cell line. The phytochemical analysis of all the plant's extract was studied using standard protocol. The cytotoxicity of the methanol extracts was determined by MTT reduction assay. The effect of the same extract was also tested for development of apoptosis features in DL cells using a fluorescence microscope and flowcytometry. The underlying mechanism closely associated with apoptotic cell death was also studied by measuring reactive oxygen species (ROS), mitochondrial membrane potential, and expression level of apoptosis inducing proteins. Murraya koenigii induced more apoptotic features in DL cells, followed by Annona reticulate. The decrease in mitochondrial membrane potential, release of cytochrome- c, increase in ROS level and higher expression of caspases (3 and 9) after plant extracts treatment may cause involvement of mitochondria in the process of apoptosis. From this study, it can be concluded that the plant species mainly Murraya koenigi and Annona reticulate significantly induced cytotoxicity in DL cells through apoptosis by utilizing mitochondrial pathway.

All the plants and their secondary metabolites used in the present study were obtained from Ayurveda, with historical roots in the Indian subcontinent. The selected secondary metabolites have been experimentally validated and reported as potent antiviral agents against genetically-close human viruses. The plants have also been used as a folk medicine to treat cold, cough, asthma, bronchitis, and severe acute respiratory syndrome in India and across the globe since time immemorial. The present study aimed to assess the repurposing possibility of potent antiviral compounds with SARS-CoV-2 target proteins and also with host-specific receptor and activator protease that facilitates the viral entry into the host body. Molecular docking (MDc) was performed to study molecular affinities of antiviral compounds with aforesaid target proteins. The top-scoring conformations identified through docking analysis were further validated by 100 ns molecular dynamic (MD) simulation run. The stability of the conformation was studied in detail by investigating the binding free energy using MM-PBSA method. Finally, the binding affinities of all the compounds were also compared with a reference ligand, remdesivir, against the target protein RdRp. Additionally, pharmacophore features, 3D structure alignment of potent compounds and Bayesian machine learning model were also used to support the MDc and MD simulation. Overall, the study emphasized that curcumin possesses a strong binding ability with host-specific receptors, furin and ACE2. In contrast, gingerol has shown strong interactions with spike protein, and RdRp and quercetin with main protease (Mpro) of SARS-CoV-2. In fact, all these target proteins play an essential role in mediating viral replication, and therefore, compounds targeting aforesaid target proteins are expected to block the viral replication and transcription. Overall, gingerol, curcumin and quercetin own multitarget binding ability that can be used alone or in combination to enhance therapeutic efficacy against COVID-19. The obtained results encourage further in vitro and in vivo investigations and also support the traditional use of antiviral plants preventively.

Cantharidin, a type of terpenoid, is the blistering agent of blister beetles frequently used in traditional medicine. The isolation and anticancer activity of cantharidin from blister beetles,Mylabris cichoriihas been recently reported by us. This study deals with changes in mitochondrial structure and function and understanding their significance in the underlying mechanism(s) in cantharidin-mediated antitumor effects in Dalton's lymphoma (DL) bearing mice. Cantharidin treatment caused the appearance of abnormal mitochondrial features which included roundish mitochondria with thickened membranes, irregularity in cristae, and appearance of small and large size vacuoles in mitochondria of DL cells. Cantharidin treatment resulted in a decrease in mitochondrial reduced glutathione, succinate dehydrogenase activity, mitochondrial membrane potential, and induced apoptosis and necrosis in DL cells. The decrease/release of mitochondrial cytochrome c were also observed after cantharidin treatment. Flow cytometry-based cell cycle analysis showed a time-dependent accumulation of the sub-G0 population of DL cells, thus, confirming the involvement of apoptosis in tumor cells in cantharidin-mediated antitumor activity. These finding signify that the apoptosis induced by cantharidin in DL cells should involve mitochondrial-dependent pathways. It is suggested that these cantharidin-mediated changes in mitochondria may play a crucial role in its antitumor activity.

Two new coordination solids [Cu₂(μ²-Bz)₄(CH₃OH)₂][Cu₂(η²-Bz)₂(phen)₂(H₂O)₂]·(NO₃)₂ (1) and [Cu(phen)(H₂O)(Bz)(η²-Bz)] (2) (phen = 1,10-phenanthroline; Bz = benzoate) have been synthesized and characterized using elemental analysis, TGA, spectroscopic (IR, UV-vis-NIR and ESR) and single crystal X-ray diffraction techniques. Change of the solvent from methanol to DMF results in changes in the architectures that are triggered by a change from square pyramidal to octahedral coordination at the divalent metal centers for complexes 1 and 2 respectively. The structural topology of the complexes is established by the interplay of strong O–H⋯O and weak C–H⋯O, C–H⋯C, π–π stacking interactions. Unconventional parallel intramolecular and anti-parallel intermolecular contacts involving the chelate rings (CR) also stabilize the structures. The energetic analyses of the structures evidence that the parallel arrangement is energetically favoured which is likely due to the presence of the Cu⋯Cu cuprophilic interaction in 1 that is not established in 2. Compound 1 exhibits the highest antibacterial activity against Rhizobium leguminosarum among the tested cultures. In vitro cytotoxicity and apoptosis studies were carried out for compounds 1 and 2 on malignant Dalton's lymphoma cell line (DL). Both compounds showed a significant effect on the decrease in cell viability as compared to a control, while compound 2 induced remarkable cytotoxicity towards DL cells. Treatment also showed the appearance of membrane blebbing, chromatin condensation and fragmented nuclei which are typical characteristic features of apoptotic cell death. Furthermore, a docking study revealed that both compounds docked in the active sites of all the cancer target proteins under study. Moreover, SAR analysis revealed that oxygen and nitrogen atoms of compound 1 and the oxygen atoms of compound 2 are crucial for biological activities.