S.V. Mirudhula

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.