Evaluation of Diuretic and Laxative properties of two mangrove plants Kandelia candel (Gura) and Brownlowia tersa (Sundori lota) from Sunderbans as well as the phytochemical characterization of their bioactive fraction(s).

This project work was designed to investigate different fractionated extracts (in ethanol, n-hexane, chloroform, ethyl acetate and water) of two mangrove plants Kandelia candel and Brownlowia tersa for diuretic and laxative potentials and their phytochemical nature. In diuretic test, frusemide (5 mg/kg body weight) was used as standard drug and the parameters like volume of urine up to 6^thhour, pH, density, conductivity and electrolyte contents of collected urine (Na⁺, K⁺, Cl^-) were measured. Among the four fractions of leaves of Kandelia candel, ethyl acetate fraction showed significant diuretic activity (p<0.001) at dose 200 mg/kg and 400 mg/kbw compared with control. For aerial parts of Brownlowia tersa, chloroform fraction demonstrated more diuretic activity. Upon urine analysis for ions, pH and conductivity, both the samples were found to work as loop diuretics mechanism, having carbonic anhydrase inhibitory effect also. In laxative activity test, bisacodyl (10 mg/kg body weight) was used as standard drug and a significant percent increment of fecal output (p<0.0001) was observed for ethyl acetate fraction of Kandelia candel at dose 200 and 400 mg/kbw. For Brownlowia, the ethyl acetate and water fractions demonstrated significant laxative effect. Then one of the most bioactive fractions for each plant (i.e. ethyl acetate fractions for Kandelia candel and chloroform fraction for Brownlowia tersa) was subjected to column chromatography. One single spot (R_f value: 0.25, in mobile phase 20% ethyl acetate: 80% n-hexane) was isolated (1.25 mg pure compound) for Kandelia candel and in case of Brownlowia tersa the R_f value of isolated single spot (1.45 mg pure compound) was as 0.3 in 30% ethyl acetate:70% n- hexane solvent system. Phytochemical analysis of fractionated extracts for both the plants exhibited the presence of carbohydrate, reducing sugar, steroids, saponins, glycosides, tannins, alkaloids, terpenoids and flavonoids etc. Further spectroscopic techniques (NMR, Mass) may reveal the chemical structure of these pure fractions.

• Research Project