Phytochemical profiles and therapeutic applications of selected medicinal plants: an evidence-based narrative review

The significant medicinal constituents and pharmacological potential of several botanicals suggest promising therapeutic applications. Scorzonera undulata displayed a diverse phytochemical profile, with 25 volatile and 21 phenolic compounds identified, including quinic and chlorogenic acids, along with flavonoids such as kaempferol, apigenin, luteolin derivatives, quercitrin, and naringin—mostly concentrated in the aerial parts. These extracts exhibited notable antioxidant, antimicrobial, anti-inflammatory, and cytotoxic activities, especially methanolic extracts against MCF-7 breast cancer cells, indicating therapeutic relevance. Andrographis paniculata extracts, rich in andrographolide, showed clinical potential in alleviating mild COVID-19 symptoms. However, the compound’s nonlinear pharmacokinetics highlight the need for optimized delivery strategies. Morinda citrifolia fruit extracts demonstrated considerable in vitro antimicrobial effects and moderate cytotoxicity, supported by UPLC–Orbitrap MS identification of unique bioactives. These findings reinforce the need for further pharmacological and clinical validation. The antiviral efficacy of Houttuynia cordata against dengue virus type 2 was evident, with aqueous extracts showing strong virucidal action and inhibition of viral replication. Hyperoside was identified as the dominant active constituent, supported by a rich phytochemical profile including flavonoids, aristolactams, and triterpenoids. Genotoxicity assessments indicated a favorable safety profile, suggesting potential for phytotherapeutic development. Achillea millefolium (yarrow) contained essential oils enriched in camphor, 1,8-cineole, artemisia ketone, and azulene derivatives, alongside phenolic acids and flavonoids like chlorogenic acid, apigenin, luteolin, and quercetin. These contributed to its antioxidant, anti-inflammatory, antimicrobial, and hemostatic effects, validating traditional medicinal applications and warranting clinical standardization. Flavonoids such as luteolin and apigenin offered anticancer and cardiovascular benefits by inhibiting PD-L1 via STAT3 suppression and promoting autophagy to counter vascular calcification. Bryophyllum pinnatum demonstrated broad pharmacological activity attributed to bufadienolides, flavonoids, and phenolic acids, supporting its ethnomedicinal use while emphasizing the need for clinical safety validation.