Sheikh Zahir Raihan

Antibacterial activity of two limonoids from Swietenia mahagoni against multiple-drug-resistant (MDR) bacterial strains.

Solvent partitioning followed by column chromatography of the MeOH extract of the seeds of Swietenia mahagoni afforded two limonoids, swietenolide (1) and 2-hydroxy-3-O-tigloylswietenolide (2). The compounds were identified by spectroscopic means. The antibacterial activity of these compounds was assessed against eight multiple-drug-resistant bacterial strains (clinical isolates) by the conventional disc diffusion method. While both compounds were active against all test organisms, compound 2 displayed overall more potent activity than compound 1.

Emergence of Multidrug Resistant Extended-Spectrum β-Lactamase Producing Eshcherichia coli Associated With Urinary Tract Infections in Bangladesh.

The incidence of infections due to extended-spectrum β-lactamase (ESBL)–producing Escherichia coli has been increased dramatically in recent years. Treatment is difficult because of frequent multidrug resistance. To identify the sensitivity of commonly used antibiotics, 36 ESBL producing E. coli strains were isolated from young adult female patients in a govt. medical college hospital in Bangladesh. The samples were studied for antimicrobial sensitivity against nine (9) commonly used antibiotics namely ampicillin (amp), trimethoprim-sulfomethoxazole (tms), tetracycline (tet), ciprofloxacin (cip), mecillinum (mel), ceftriaxone (cef), nalidixic acid (nal), Azithromycin (azm) and Chloramphenicol (chl) and the MIC values were determined by agar dilution method. Overall, 72% of the strains were multidrug resistant (MDR) i.e. resistant to two or more drugs. Among 36 strains, 14 isolates were initially found to be resistant against third generation cephalosporin, ceftriaxone. Those were subjected to the test for production of ESBL (Extended Spectrum β-Lactamase) and 7 showed positive results.

Evaluation of antinociceptive, anti-inflammatory and anxiolytic activities of methanolic extract of Terminalia citrina leaves

Abstract Objective To investigate the antinociceptive, anti-inflammatory and anxiolytic effects of methanolic extracts of Terminalia citrina (T. citrina) leaves (Family: Combretaceae). Methods The antinociceptive activity was evaluated by acetic acid induced writhing method and radiant heat tail flick method while anti-inflammatory activity was evaluated by human red blood cell membrane stabilization method and anxiolytic activity by elevated plus maze model. Results The methanolic extract of T. citrina leaves showed significant antinociceptive, anti-inflammatory and anxiolytic effects in dose dependent manner compared to their respective standard drugs. Conclusions The present study demonstrated that T. citrina possesses antinociceptive, anti-inflammatory and anxiolytic effects.

Phytochemical screening and in vitro anthelmintic activity of methanol extract of Terminalia citrina leaves

Abstract Objective To evaluate anthelmintic activity of methanolic extract of leaves of Terminalia citrina ( T. citrina ) plant belonging to the Combretaceae family. Methods The tests of phytochemical screening included alkaloids, flavonoids, tannins, saponins, quinines, anthocyanins, glycosides, carbohydrates and reducing sugars. The anthelmintic activity of methanolic extract of leaves of T. citrina was evaluated against Pheretima posthuma at three different concentrations (25 mg/mL, 50 mg/mL and 100 mg/mL) of extracts which involved determination of time of paralysis and time of death of worms. Results The phytochemical screening of T. citrina leaves revealed the presence of flavonoids, tannins, alkaloids, carbohydrates and reducing sugars. The present study indicated that methanolic extract significantly exhibited paralysis and also caused death of worms especially at highest concentration of 100 mg/mL, as compared to standard reference Albendazole (10 mg/mL). Conclusions This study suggests that the leaves of T. citrina possess potent anthelmintic activity.

Ethnopharmacological investigation of the aerial part of Phragmites karka (Poaceae)

Abstract Background: In this ethnopharmacological study, methanolic extract of the aerial plant parts of Phragmites karka (Family: Poaceae) and its petroleum ether and carbon tetrachloride fractions were investigated for bioactivities in Swiss-albino mice, namely, analgesic, central nervous system (CNS) depressant, hypoglycemic, and antidiarrheal activity. Methods: The cold methanolic extract of the aerial plant parts of Phragmites karka (MEPK) was first prepared, and it was then further fractionated as petroleum ether (PEFMEPK) and carbon tetrachloride (CTFMEPK) fractions. Analgesic activity was performed employing acidic acid-induced writhing test, central analgesic effect by radiant heat tail-flick method. CNS depressant activity was evaluated by phenobarbitone-induced sleeping time test. Hypoglycemic activity was tested by glucose tolerance test (GTT). Antidiarrheal activity was evaluated by castor oil-induced diarrhea method. For all in vivo tests, doses of 200 and 400 mg/kg body weight were used. Results: In the mice model, the MEPK, PEFMEPK, and CTFMEPK fractions showed significant peripheral analgesic activity at a dose of 400 mg/kg body weight with percentage of inhibition of acetic acid-induced writhing 77.67 (p<0.001), 33.50 (p<0.001), and 40.29 (p<0.001), respectively, compared to the standard dichlofenac (60.68%, p<0.001) group. The hypoglycemic properties of MEPK, PEFMEPK, and CTFMEPK extracts were evaluated in normoglycemic mice where the reduction of blood glucose level after 30 min of glucose load were 69.85%, 78.91%, and 72.73%, respectively, and for standard glibenclamide, the reduction was 72.85%. All results were significant (p<0.05). In the case of the CNS depressant activity by phenobarbitone-induced sleeping time test, the crude ME significantly reduced sleep latency by 57.14% and increased the duration of sleep by 63.29% compared to the control, which were comparable to that of standard diazepam (65.71% and 77.62%, respectively). Among all the extract and fractions, methanolic extract showed the maximum antidiarrheal effect. The methanolic extract at 200 mg/kg dose induced a significant decrease in the total number of defecation in 4 h (69.05% of inhibition, p<0.001) and at 400 mg/kg dose showed 76.19% of inhibition (p<0.001). Conclusions: In light of the available literature, these findings represent the first experimental investigation of biological activities of P. karka in the perspective of their traditional use.