Bionanotechnology is a branch of science that has revolutionized modern science and technology. Nanomaterials, especially noble metals, have attracted researchers due to their size and application in different branches of sciences that benefit humanity. Metal nanoparticles can be synthesized using green methods, which are good for the environment, economically viable, and facilitate synthesis. Due to their size and form, gold nanoparticles have become significant. Plant materials are of particular interest in the synthesis and manufacture of theranostic gold nanoparticles (NPs), which have been generated using various materials. On the other hand, chemically produced nanoparticles have several drawbacks in terms of cost, toxicity, and effectiveness. A plant-mediated integration of metallic nanoparticles has been developed in the field of nanotechnology to overcome the drawbacks of traditional synthesis, such as physical and synthetic strategies. Nanomaterials′ tunable features make them sophisticated tools in the biomedical platform, especially for developing new diagnostics and therapeutics for malignancy, neurodegenerative, and other chronic disorders. Therefore, this review outlines the theranostic approach, the different plant materials utilized in theranostic applications, and future directions based on current breakthroughs in these fields.

Zinc Oxide Nanoparticles (ZnONPs) are one of the most widely used metal oxide nanoparticles in biological applications because of their outstanding biocompatibility, affordability, and low toxicity. In biomedicine, ZnONPs have shown promise, particularly in the disciplines of anticancer and antibacterial fields. In comparison to other standard synthesis methods, the environmentally-friendly synthesis of metallic nanoparticles utilizing various plant extracts is a good option. The current research focuses on the synthesis of zinc oxide nanoparticles (ZnONPs) from R. sativus leaf extract under various physical conditions (Precipitation method). Analytical methods were used to confirm and characterize the produced ZnONPs. The spherical nature of the produced nanoparticles was established by SEM analysis. The generation of very pure ZnONPs was confirmed by EDS data. The crystalline nature of the produced nanoparticles, with a particle size of 66.47 nm, was confirmed by XRD. The XRD graphs’ presence of the (100), (002), and (101) planes strongly suggest the production of wurtzite ZnO. The visual and infrared area exhibits transmissions of 84 percent in the pH 10 nanoparticles. The band gap of the nanoparticles increases from 3.34 to 3.38 eV when the pH increases. These nanoparticles were effective against both Gram-positive and Gram-negative bacteria. The effect of several process parameters such as pH and temperature were investigated, and the best conditions were discovered to be pH 12 and 80 °C, respectively. The effect of ZnONPs was tested with human breast cancer cells (MCF-7), and they showed significant cytotoxic results. Collectively, our data suggest that ZnONPs of R. sativus leaf extract inhibit breast cancer cell lines. The ZnONPs are, therefore, a prospective source of chemopreventive drugs that merit additional exploration in order to uncover lead compounds with cancer chemotherapeutic potential.

Enzymes that degrade pectin are called pectinases. Pectinases of microbial origin are used in juice clarification as the process is cost-effective. This study screened a pectinase-producing bacterium isolated from soil and identified as Bacillus subtilis 15A B-92 based on the 16S rRNA molecular technique. The purified pectinase from the isolate showed 99.6 U/mg specific activity and 11.6-fold purity. The molecular weight of the purified bacterial pectinase was 14.41 ± 1 kD. Optimum pectinase activity was found at pH 4.5 and 50 °C, and the enzyme was 100% stable for 3.5 h in these conditions. No enzymatic inhibition or activation effect was seen with Fe²⁺, Ca²⁺, or Mg²⁺. However, a slight inhibition was seen with Cu²⁺, Mn²⁺, and Zn²⁺. Tween 20 and 80 slightly inhibited the pectinase, whereas iodoacetic acid (IAA), ethylenediaminetetraacetate (EDTA), urea, and sodium dodecyl sulfate (SDS) showed potent inhibition. The bacterial pectinase degraded citrus pectin (100%); however, it was inactive in the presence of galactose. With citrus pectin as the substrate, the Km and Vmax were calculated as 1.72 mg/mL and 1609 U/g, respectively. The high affinity of pectinase for its substrate makes the process cost-effective when utilized in food industries. The obtained pectinase was able to clarify orange and apple juices, justifying its application in the food industry.

Oral cancer has a high mortality rate, which is mostly determined by the stage of the disease at the time of admission. Around half of all patients with oral cancer report with advanced illness. Hitherto, chemotherapy is preferred to treat oral cancer, but the emergence of resistance to anti-cancer drugs is likely to occur after a sequence of treatments. Curcumin is renowned for its anticancer potential but its marred water solubility and poor bioavailability limit its use in treating multidrug-resistant cancers. As part of this investigation, we prepared and characterized Curcumin nanomicelles (CUR-NMs) using DSPE-PEG-2000 and evaluated the anticancer properties of cisplatin-resistant cancer cell lines. The prepared CUR-NMs were sphere-shaped and unilamellar in structure, with a size of 32.60 ± 4.2 nm. CUR-NMs exhibited high entrapment efficiency (82.2%), entrapment content (147.96 µg/mL), and a mean zeta potential of −17.5ζ which is considered moderately stable. The cellular uptake and cytotoxicity studies revealed that CUR-NMs had significantly higher cytotoxicity and cellular uptake in cisplatin drug-resistant oral cancer cell lines and parental oral cancer cells compared to plain curcumin (CUR). The DAPI and FACS analysis corroborated a high percentage of apoptotic cells with CUR-NMs (31.14%) compared to neat CUR (19.72%) treatment. Conclusively, CUR-NMs can potentially be used as an alternative carrier system to improve the therapeutic effects of curcumin in the treatment of cisplatin-resistant human oral cancer.

The applications of bioactive compounds from medicinal plants as therapeutic drugs are largely increasing. The present study selected the bioactive compounds from Acacia concinna (A. concinna) and Citrus limon (C. limon) to assess their phytochemicals, proteins, and biological activity. The plant material was collected, and extraction performed as per the standard procedure. Qualitative analysis was undertaken, and identification of functional organic groups was performed by FTIR and HPLC. Antibacterial, anticancer, antioxidant, antihyperglycemic, antihyperlipidemic, and inhibition kinetics studies for enzymes were performed to assess the different biological activities. Flavonoids and phenols were present in a significant amount in both the selected plants. A. concinna showed significant antimicrobial activity against Z. mobilis, E. coli, and S. aureus, with minimum inhibition zones (MIZ) of 24, 22, and 20 mm, respectively. C. limon strongly inhibited all the tested pathogenic bacteria with maximum and minimum MIZ of 32 and 17 mm. A. concinna silver nanoparticles also exhibited potent antimicrobial activity. Both extracts showed substantial antioxidant, antihyperlipidemic, antidiabetic, anticancer (MCF-7), and anti-urease (antiulcer) properties. To conclude, these plants can be used to treat hyperlipidemia, diabetes, cancer, and gastrointestinal ulcers. They can also serve as antimicrobial and antioxidant agents. Thus, the studied plants must be exploited cost-effectively to generate therapeutic drugs for various diseases.

Cancer is characterized by the abnormal development of cells that divide in an uncontrolled manner and further take over the body and destroy the normal cells of the body. Although several therapies are practiced, the demand and need for new therapeutic agents are ever-increasing because of issues with the safety, efficacy and efficiency of old drugs. Several plant-based therapeutics are being used for treatment, either as conjugates with existing drugs or as standalone formulations. Withania somnifera (L.) Dunal is a highly studied medicinal plant which is known to possess immunomodulatory activity as well as anticancer properties. The pivotal role of KAT6A in major cellular pathways and its oncogenic nature make it an important target in cancer treatment. Based on the literature and curated datasets, twenty-six compounds from the root of W. somnifera and a standard inhibitor were docked with the target KAT6A using Autodock vina. The compounds and the inhibitor complexes were subjected to molecular dynamics simulation (50 ns) using Desmond to understand the stability and interactions. The top compounds (based on the docking score of less than −8.5 kcal/mol) were evaluated in comparison to the inhibitor. Based on interactions at ARG655, LEU686, GLN760, ARG660, LEU689 and LYS763 amino acids with the inhibitor WM-8014, the compounds from W. somnifera were evaluated. Withanolide D, Withasomniferol C, Withanolide E, 27-Hydroxywithanone, Withanolide G, Withasomniferol B and Sitoindoside IX showed high stability with the residues of interest. The cell viability of human breast cancer MCF-7 cells was evaluated by treating them with W. Somnifera root extract using an MTT assay, which showed inhibitory activity with an IC50 value of 45 µg/mL. The data from the study support the traditional practice of W. somnifera as an anticancer herb.