Stenochlaena palustris is a widely found fern in mangrove forests and other areas of different countries over the world. This plant has many uses in traditional medicine of many countries. This study was conducted on its leaves extract to investigate its different phytochemical and pharmacological properties based on its local medicinal uses. Phytochemical screening indicated the presence of different secondary metabolites in this plant. On silica coated TLC plates, the extract exhibited the presence of different antioxidative compounds. Total phenolic, flavonoid and tannin contents were determined (97 mg GAE/g, 90 mg QE/g and 23 mg GAE/g, respectively). This extract also scavenged DPPH, hydrogen peroxide and superoxide radicals (SC50 = 80, 158 and 236 μg/ml, respectively). It also showed ferric ion reducing capability (RC50 =166 μg/ml). This plant showed significant antihyperglycemic, peripheral analgesic (acetic acid induced), anti-inflammatory (formaldehyde induced) and laxative activities in mice. This plant also showed little cytotoxic activity in brine shrimp lethality bioassay. These results are also compared with respective standard drugs and our findings justified its traditional usage.

Background: Ceriops decandra (Griff.) Ding Hou is used conventionally for managing a number of therapeutic conditions including diabetes, haemorrhage, pain, diarrhea, angina, and dysentery etc. Furthermore, Ceriops tagal Linn is used to treat hemorrhage, acariasis, wound infection, malaria, malignant diabetes and ulcers etc in folk medicine. The present study was designed to evaluate the comparative pharmacological activities of leaves of these two medicinal plants of the Sundarbans. Methods: Antioxidant activity was assessed by total phenolic, total flavonoids, total tannin content, and DPPH free radical scavenging assays. Acetic acid-induced test for analgesic, oral glucose tolerance test for antihyperglycemic, open field test for neurobehavioral, prothrombin time test for anticoagulant, anthelmintic potential on Paramphistomum cervi, and in-vivo cytotoxicity test on brine shrimp nauplii were used for appraising pharmacological activities of both extracts. Results: C. decandra extract revealed greater radical scavenging activity than that of C. tagal. C. decandra extract significantly (P < 0.05) reduced writhing inhibition of 54.55% and 66.37% at 500mg/kg and 250 mg/kg, respectively. In oral glucose tolerance test, C. decandra significantly lowered the blood glucose level for pretreated mice with glucose by 25.76%, 2272%, and 31.88%, 38.71% respectively, at 60 min and 120min at the 250 mg/kg, and 500 mg/kg dose level. But, the reduction of blood glucose level by C. tagal extract was less than that of C. decandra. Furthermore, C. decandra produced a sedative effect at both doses starting from 30 min to 120 min of experimental period. The crude extract of C. decandra and C. tagal delayed the prothrombin time in a dose dependently. The C. decandra and C. tagal produced dose-dependent paralysis and death time. The LC50 values obtained from brine shrimp lethality bioassay were 94.69, 114.29 µg/mL for C. decandra and C. tagal, respectively. Conclusion: C. decandra revealed prominent pharmacological activities than that of C. tagal. Also, the present study confirmed the scientific evidence of both plants.

Sonneratia caseolaris (L.) is a common mangrove plant which has significant medicinal value in traditional medicine. Ethanol extract from the fruits of S. caseolaris (SCE) was used in this project to explore its different pharmacological effects considering its traditional usage. In the castor oil-induced diarrheal method, SCE significantly lengthened the latency of the first defecation period up to 95.8 and 119.4 min as well as lowering stool count by 43.3% and 64.4% at the doses of 250 and 500 mg/kg, respectively. In evaluating the neuropharmacological effect using the open-field model, a significant central nervous system (CNS) depressant nature was observed after a reduction in the no. of squares crossed by mice at various time intervals. In evaluating the blood coagulation effect, SCE significantly reduced blood clotting time at 5.86, 5.52, and 5.01 min at 25, 50, and 100 mg/ml doses, respectively. In the assessment of the anthelmintic effect, SCE significantly killed Paramphistomum cervi (P. cervi) where the death times of the nematodes were 40.3, 36.8, and 29.9 min at 12.5, 25, and 50 mg/ml doses, respectively. The extract showed a very poor cytotoxic effect in brine shrimp lethality bioassay. In molecular docking analysis, maslinic acid, oleanolic acid, luteolin, luteolin 7-O-β-glucoside, myricetin, ellagic acid, and R-nyasol showed the best binding affinities with the selected proteins which might be the credible reasons for eliciting pharmacological responses. Among these seven compounds, only luteolin 7-O-β-glucoside had two violations in Lipinski’s rule of five.