eng Oriental Scientific Publishing Company Biosciences Biotechnology Research Asia 0973-1245 2025-03-25 22 1 335 348 10.13005/bbra/3365 54408 article Kruti Dave 1 Birva Limbachiya 1 Heer Tank 1 Department of Biotechnology, Mehsana Urban Institute of Sciences, Ganpat University, Kherva, Gujarat, India This study explores the phytotherapeutic potential of Psidium guajava L. (Leaves) and Withania coagulans (Berries) through an in-depth assessment of the antidiabetic, antioxidant, antimicrobial, and anticancer activities of four extracts prepared using the maceration method with methanol and water. The presence of flavonoids, tannins, terpenoids, and saponins in all four extracts was revealed using Phytochemical screening. The antidiabetic activity was assessed across all extracts, with the methanolic extract of Psidium guajava L. exhibiting the strongest effect, followed by both extracts of Withania coagulans, which demonstrated notable efficacy. The antioxidant activity was highest in the Psidium guajava L methanolic extract, compared to the other three extracts. Antimicrobial activity against Staphylococcus aureus was evaluated for all extracts, with the methanolic extract of Withania coagulans showing the most significant inhibitory effect. In anticancer assays targeting lung cancer cells, the Withania coagulans extracts displayed promising potential, particularly the methanolic extract. Given the strong bioactivity observed in the methanolic extracts of both plants, GC-MS analysis was carried out to pinpoint the bioactive compounds responsible for their therapeutic effects. The study sheds light on the potential of Psidium guajava L. and Withania coagulans as rich sources of bioactive compounds, offering promising applications in phytotherapy for managing diabetes, oxidative stress, microbial infections, and cancer. https://www.biotech-asia.org/vol22no1/phytotherapy-based-insights-antidiabetic-antioxidant-antimicrobial-and-anticancer-activities-of-psidium-guajava-l-and-withania-coagulans-with-gas-chromatography-mass-spectrometry-profiling/ Anticancer activity; Antidiabetic activity; Antimicrobial activity; Antioxidant activity; GC-MS;  Phytotherapy; Psidium guajava L.; Withania coagulans.