Bioactive compounds

Medicinal plants have served as a primary source of therapeutic agents throughout human history and continue to contribute significantly to modern pharmacotherapy. In recent decades, the renewed interest in plant-based medicines has been driven by increasing concerns over the adverse effects of synthetic drugs, rising healthcare costs, and a global shift toward natural and sustainable therapeutic options. However, the transition from traditional knowledge to evidence-based medicine requires systematic validation through scientifically robust methodologies. In vitro screening techniques have emerged as essential tools in this process, enabling the rapid and controlled evaluation of biological activities associated with plant-derived compounds. These methods facilitate the identification of pharmacologically active constituents, elucidation of mechanisms of action, and preliminary assessment of safety profiles. This review provides a comprehensive and critical overview of in vitro approaches used in medicinal plant research, including phytochemical analysis, antioxidant assays, cytotoxic and anticancer evaluations, antimicrobial testing, and advanced cell-based models. Particular emphasis is placed on the importance of sample preparation, authentication, extraction, and standardization, as these factors significantly influence reproducibility and experimental reliability. Furthermore, the applications of in vitro screening in drug discovery, validation of ethnomedicinal claims, toxicity assessment, and nutraceutical development are discussed in detail. Despite inherent limitations in mimicking complex in vivo systems, in vitro methodologies remain indispensable due to their efficiency, cost-effectiveness, and adaptability to high-throughput platforms. Overall, this review highlights the pivotal role of in vitro screening as a scientific bridge connecting traditional medicinal knowledge with modern pharmaceutical research, thereby facilitating the rational development of plant-based therapeutics.

Ancient medicinal plants have been in use across cultures for the treatment of microbial infections. The recent upsurge in antibiotic resistance has created interest in the discovery of plant-based remedies with antimicrobial activity. In this research, the phytochemical profile and antimicrobial potential of three traditional medicinal plants, Azadirachta indica (Neem), Ocimum sanctum (Tulsi), and Withania somnifera (Ashwagandha), which are well known for their ethnomedicinal uses, were examined. The objective was to evaluate their potential as alternative antimicrobial agents. Phytochemical screening presented the existence of alkaloids, flavonoids, tannins, and saponins in different concentrations in the plant extracts. Antimicrobial activity was determined by the agar well diffusion method, and statistical analysis proved differences in antimicrobial potency among the plant extracts to be significant. Withania somnifera showed the greatest antimicrobial activity, with Ocimum sanctum showing intermediate activity, while Azadirachta indica showed the lowest activity. There was a high positive correlation between the content of alkaloids and antimicrobial activity.