Compared to traditional physical and chemical approaches, nanobiotechnology and plant-based green synthesis procedures offer significant advantages, as well as having a greater range of medical and biotechnological applications. Nanoparticles of zinc oxide (ZnO NPs) have recently been recognized as a promising option for many industries, including optics, electrics, packaged foods, and medicine, due to their biocompatibility, low cytotoxicity, and cost-effectiveness. Several studies have shown that zinc ions are important in triggering cell apoptosis by promoting the generation of reactive oxygen species (ROSs) and releasing zinc ions (Zn²⁺), which are toxic to cells. The toxic nature of the chemicals used in the synthesis of ZnO nanoparticles limits their clinical utility. An overview of recent developments in green ZnO NP synthesis is presented in this review, emphasizing plant parts as reducing agents and their medical applications, including their antimicrobial, anticancer, antioxidant, and anti-inflammatory properties, as well as key mechanisms of action for these applications to facilitate further research on the biomedical fields in the future.

Curcuma species are widely used as a food additive and also in various medicinal purposes. The plant is a rich source of essential oil and is predominantly extracted from the rhizomes. On the other hand, the leaves of the plants are usually considered as an agrowaste. The valorization of these Curcuma leaf wastes into essential oils is becoming accepted globally. In the present study, we aim to extract essential oils from the leaves of Curcuma longa (LEO), C. aromatica (REO), and C. anguistifolia (NEO). The chemical composition of these essential oils was analyzed by GC-MS. Free radical scavenging properties were evaluated against the radical sources, including DPPH, ABTS, and hydrogen peroxide. The antibacterial activity was assessed by the disc diffusion method and Minimum inhibitory concentration analysis against Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli, Pseudomonas aeruginosa and Salmonella enterica) bacteria. Results identified the compounds α-phellandrene, 2-carene, and eucalyptol as predominant in LEO. The REO was predominated by camphor, 2-bornanone, and curdione. The main components detected in NEO were eucalyptol, curzerenone, α-lemenone, longiverbenone, and α-curcumene. Antioxidant properties were higher in the LEO with IC₅₀ values of 8.62 ± 0.18, 9.21 ± 0.29, and 4.35 ± 0.16 μg/mL, against DPPH, ABTS, and hydrogen peroxide radicals. The cytotoxic activity was also evident against breast cancer cell lines MCF-7 and MDA-MB-231 cells; the LEO was found to be the most active against these two cell lines (IC₅₀ values of 40.74 ± 2.19 and 45.17 ± 2.36 μg/mL). Likewise, the results indicated a higher antibacterial activity for Curcuma longa essential oil with respective IC₅₀ values (20.6 ± 0.3, 22.2 ± 0.3, 20.4 ± 0.2, and 17.6 ± 0.2 mm). Hence, the present study confirms the possible utility of leaf agrowastes of different Curcuma spp. as a possible source of essential oils with pharmacological potential.

Plants have been employed in therapeutic applications against various infectious and chronic diseases from ancient times. Various traditional medicines and folk systems have utilized numerous plants and plant products, which act as sources of drug candidates for modern medicine. Artemisia is a genus of the Asteraceae family with more than 500 species; however, many of these species are less explored for their biological efficacy, and several others are lacking scientific explanations for their uses. Artemisia nilagirica is a plant that is widely found in the Western Ghats, Kerala, India and is a prominent member of the genus. In the current study, the phytochemical composition and the antioxidant, enzyme-inhibitory, anti-inflammatory, and anticancer activities were examined. The results indicated that the ethanol extract of A. nilagirica indicated in vitro DPPH scavenging (23.12 ± 1.28 µg/mL), ABTS scavenging (27.44 ± 1.88 µg/mL), H₂O₂ scavenging (12.92 ± 1.05 µg/mL), and FRAP (5.42 ± 0.19 µg/mL). The anti-inflammatory effect was also noticed in the Raw 264.7 macrophages, where pretreatment with the extract reduced the LPS-stimulated production of cytokines (p < 0.05). A. nilagirica was also efficient in inhibiting the activities of α-amylase (38.42 ± 2.71 µg/mL), α-glucosidase (55.31 ± 2.16 µg/mL), aldose reductase (17.42 ± 0.87 µg/mL), and sorbitol dehydrogenase (29.57 ± 1.46 µg/mL). It also induced significant inhibition of proliferation in breast (MCF7 IC₅₀ = 41.79 ± 1.07, MDAMB231 IC₅₀ = 55.37 ± 2.11µg/mL) and colon (49.57 ± 1.46 µg/mL) cancer cells. The results of the phytochemical screening indicated a higher level of polyphenols and flavonoids in the extract and the LCMS analysis revealed the presence of various bioactive constituents including artemisinin.

Oroxylum indicum is a traditionally used plant in Ayurvedic and folk medicines. The plant is useful for the management of gastrointestinal diseases as well as skin diseases. In the present study, we analyzed the antitumor potential of O. indicum in Dalton’s lymphoma ascites tumor cells (DLA) and Ehrlich ascites carcinoma (EAC)-induced solid and ascites tumors. Further, the potential of O. indicum extract (OIM) on skin papilloma induction by dimethyl benz(a) anthracene (DMBA) and croton oil was evaluated. The chemical composition of the extract was analyzed using UPLC-Q-TOF-MS. The predominant compounds present in the extract were demethoxycentaureidin 7-O-rutinoside, isorhamnetin-3-O-rutinoside, baicalein-7-O-glucuronide, 5,6,7-trihydroxyflavone, 3-Hydroxy-3′,4′,5′-trimethoxyflavone, 5,7-dihydroxy-3-(4-methoxyphenyl) chromen-4-one, and 4′-Hydroxy-5,7-dimethoxyflavanone. Treatment with high-dose OIM enhanced the percentage of survival in ascites tumor-bearing mice by 34.97%. Likewise, high and low doses of OIM reduced the tumor volume in mice by 61.84% and 54.21%, respectively. Further, the skin papilloma formation was brought down by the administration of low- and high-dose groups of OIM (by 67.51% and 75.63%). Overall, the study concludes that the Oroxylum indicum root bark extract is a potentially active antitumor and anticancer agent.

Oroxylum indicum Vent is a medium-sized deciduous tree that belongs to the family Bignoniaceae. The roots of this tree are used as one of the ten ingredients to prepare the Dasamula formulation in the Ayurvedic system of medicine in India. Although traditional uses are attributed to the medicinal plant, there are limited scientific data on its potential. The present study thus analyzed the cytotoxic and apoptotic potential of the plant against different cancer cells. MTT assay was used to determine cytotoxicity using HeLa, HCT 15, and MDA-MB-231 cells, with the IC50 values, revealed at concentrations of 92.43, 133.0, and 112.84 µg/mL respectively. However, the extract was less toxic to non-cancer cells. HeLa cells further treated with OIM were subjected to flow cytometric analysis for studying the cell cycle stages. When untreated cells at G1 phase were found at a relative percentage of 71.9%, it increased to 79.3 and 86% with OIM treatment at concentrations of 50 and 100 µg/mL; cells in the S phase decreased from 10.3 to 8.2 and 7.5%, concluding the arrest of the cell cycle at G1 phase. With further study of apoptotic morphology with dual acridine orange–ethidium bromide staining and Annexin–Hoechst staining, cells at early and late apoptotic stages were observed with OIM treatment at 100 µg/mL concentration. Although such effects were noticed with OIM treatment, it could not be concluded that the extract had remarkable anti-proliferative effects, since the small changes noticed in cell cycle arrest and apoptotic induction were attained at a high concentration of OIM 100 µg/mL. The biological activities of plants and their extracts are attributed to the presence of multifarious compounds present in them. LC-MS Q-TOF analysis confirmed the presence of biochanin A and baicalein in OIM. HPLC-based quantification of baicalein and chrysin was shown to be 3.36 and 1.11 mg/gram dry weight. To conclude, the above results suggest that the root bark of O. indicum has a broad spectrum of biological activities, including anticancer and apoptotic properties.

Background: Minocycline (Mino) has a longer half-life than 1st-generation tetracycline. A trace element, Cu is necessary for the operation of numerous cellular enzymes as it is an essential component in free radical scavenging and enzyme redox chemistry. Methods: FT-IR, electronic spectra (UV), X-ray diffraction (XRD), thermogravimetric analysis, SEM, TEM were used to characterize the novel complex (Mino/Cu). The molar conductance value validates that the Cu (II) complex is not electrolytic. Mino is chelated with Cu (II) via (C=O) ketonic oxygen atoms and (OH) groups based on spectral data. Cu (II)’s complex surface morphology showed up as tiny rectangular projections, according to SEM analysis. TEM showed that the Cu (II) chelate formed black spots with particle sizes between 9 and 23 nm. Cytotoxicity against MCF-7 breast cancer cell proliferation and antibacterial activity against three resistant strains (Salmonella enteritidis, Klebsiella pneumonia and Bacillus subtilis) are estimated in vitro along with the scavenging capabilities of ORAC free radicals. Result: The study found that the Mino/Cu complex had strong anticancer properties, inhibiting MCF-7 proliferation growth and cancer cell viability by 57.54 µg/ml at concentrations of 100 ug/ml. It also showed strong antibacterial properties against S.enteritidis, K. pneumonia and B.subtilis at low concentrations. The complex also demonstrated high antioxidant activity with ORAC activity 1581 (µM Trolox eq/ml).