Ophiorrhiza rugosa var. prostrata is one of the most frequently used ethnomedicinal plants by the indigenous communities of Bangladesh. This study was designed to investigate the antidiarrheal, anti-inflammatory, anthelmintic and antibacterial activities of the ethanol extract of O. rugosa leaves (EEOR). The leaves were extracted with ethanol and subjected to in vivo antidiarrheal screening using the castor oil-induced diarrhea, enteropooling, and gastrointestinal transit models. Anti-inflammatory efficacy was evaluated using the histamine-induced paw edema test. In parallel, in vitro anthelmintic and antibacterial activities were evaluated using the aquatic worm and disc diffusion assays respectively. In all three diarrheal models, EEOR (100, 200 and 400 mg/kg) showed obvious inhibition of diarrheal stool frequency, reduction of the volume and weight of the intestinal contents, and significant inhibition of intestinal motility. Also, EEOR manifested dose-dependent anti-inflammatory activity. Anthelmintic action was deemed significant (P < 0.001) with respect to the onset of paralysis and helminth death. EEOR also resulted in strong zones of inhibition when tested against both Gram-positive and Gram-negative bacteria. GC-MS analysis identified 30 compounds within EEOR, and of these, 13 compounds documented as bioactive showed good binding affinities to M3 muscarinic acetylcholine, 5-HT3, tubulin and GlcN-6-P synthase protein targets in molecular docking experiments. Additionally, ADME/T and PASS analyses revealed their drug-likeness, likely safety upon consumption and possible pharmacological activities. In conclusion, our findings scientifically support the ethnomedicinal use and value of this plant, which may provide a potential source for future development of medicines.

Holigarna caustica (Dennst.), a popular plant used in folk medicine in Bangladesh, is often used by the local folk practitioner to treat a variety of chronic diseases. The present research is an attempt to find out an innovative therapeutic prospect for the management of neuropsychiatric disorders. The methanol extract of H. caustica leaves (MEHC) were utilized on various behavioral tests for assessing anxiolytic, anti-depressant, and anti-inflammatory activities. The antioxidant potentials and quantitative phytochemicals were evaluated through spectrophotometric methods. Results revealed that treatment of MEHC (200 and 400 mg/kg) significantly reduced anxiety like behaviors in mice, particularly, 400 mg/kg efficiently improved % of entries and time spent (p < 0.05) in the open arms in elevated plus maze test, whereas, superior head dipping tendency (p < 0.05) was observed in hole-board test. In contrast, mice treated with 200 mg/kg revealed better anxiolytic effect in both open field and hole-cross tests. During antidepressant evaluation, mice administrated with MEHC exhibited active behaviors (swimming and struggling) in forced swimming and tail suspension tests. In parallel, MEHC manifested a noteworthy (p < 0.001) suppression of inflammatory response induced by histamine. The MEHC also showed strong antioxidant activities in 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) (IC₅₀: 57.64 μg/mL) scavenging, H₂O₂ (IC₅₀: 51.60 μg/mL) scavenging, and ferric reducing power assay. The levels of total phenol, flavonoid, flavonol, condensed tannin, and antioxidant were estimated as higher in MEHC. Moreover, 11 compounds were documented as bioactive, displayed good binding affinities to potassium channel receptor, human serotonin receptor, cyclooxygenase (COX-1 and 2), and xanthine oxidoreductase enzyme targets in molecular docking experiments. Furthermore, ADME/T and Prediction of Activity Spectra for Substances (PASS) analyses exposed their drug-likeness, nontoxic upon consumption, and likely pharmacological actions. Overall, the H. caustica is potentially bioactive as evident by in vivo, in vitro, and computational analysis. Our findings support the folkloric value of this plant, which may provide a potential source towards developing drug leads.

Dhaiphul (Woodfordia fruticosa) is a frequently demanded plant in South-East Asian regions for its diverse medicinal values. This study was proposed to examine antioxidant, antidiabetic, and antidepressant potentials of methanol extract of W. fruticosa leaves (MEWF) and its derived n-hexane (NHFMEWF) and ethyl acetate (EAFMEWF) fractions through in vitro, in vivo, and computational models. Among test samples, MEWF and EAFMEWF contained the highest phenolic content and showed maximal antioxidant activity in DPPH radical scavenging and ferric reducing power assays. In comparison, NHFMEWF possessed maximum flavonoid content and a significantly potent α-amylase inhibitory profile comparable with positive control acarbose. In animal models of depression (forced swimming and tail suspension test), EAFMEWF and NHFMEWF demonstrated a dose-dependent antidepressant-like effect; explicitly, the depressive-like behaviors significantly declined in EAFMEWF-treated dosing groups in contrast to the control group. In the computational analysis, previously isolated flavonoid compounds from Dhaiphul leaves manifested potent binding affinity against several key therapeutic target proteins of diabetes and depressive disorders including α-amylase, serotonin transporter, dopamine transporter, and neuronal nitric oxide synthase with varying pharmacokinetics and toxicity profiles. This research's outcomes may provide potential dietary supplements for mitigating hyperglycemia, cellular toxicity, and depressive disorder.

Cuscuta reflexa Roxb. is traditionally used by the indigenous communities of Bangladesh to treat different diseases, such as pain, edema, tumor, jaundice, and skin infections. This study tested neuro-pharmacological, anti-nociceptive, and antidiarrheal activities by in vivo and in silico experiments for the metabolites extracted (methanol) from the leaves of Cuscuta reflexa (MECR). During the anxiolytic evaluation analyzed by elevated plus maze and hole board tests, MECR (200 and 400 mg/kg) exhibited a significant dose-dependent reduction of anxiety-like behavior in mice. Similarly, mice treated with MECR demonstrated a dose-dependent decrease in the time of immobility in both forced swimming and tail suspension tests. In addition, anti-nociceptive activity was assessed by the chemical-induced (acetic acid and formalin) pain models. In both cases, 400 mg/kg was found to be most effective and significantly (p < 0.001) inhibited acetic acid stimulated writhing and formalin-induced licking (pain response) in mice. Furthermore, antidiarrheal efficacy determined by the castor-oil induced diarrheal model manifested an evident inhibition of diarrheal stool frequency. In parallel, previously isolated bioactive compounds were documented based on the biological activities and subjected to in silico studies to correlate with the current pharmacological outcomes. The selected isolated compounds (15) displayed favorable binding affinities to potassium channels, human serotonin receptor, COX-1, COX-2, M3 muscarinic acetylcholine receptor, and 5-HT3 receptor proteins. Additionally, the ADME/T and toxicological properties were justified to unveil their drug-like properties and toxicity level. Overall, Cuscuta reflexa is bioactive and could be a potential source for the development of alternative medicine.