Many modern medicines used today were discovered by extracting active chemicals from plants used in traditional medicine. To identify and locate any new and potential therapeutic aaplications of commonly used medicinal plants by the folk medicinal practitioners of Noakhali, Bangladesh, we conducted a survery with a semi-structured questionnaire using the guided field-walk method. Detailed information was obtained on 143 plants belonging to 62 families. Leaves were mostly used (52%) followed by roots (30.55%) and whole plants (18.74%) along with fruits, barks, seeds, stems and flowers. Gastrointestinal disorders were the most common diseases treated followed by respiratory tract infections, weakness, fever, diabetes, skin disorders, sexually transmitted diseases, hepatic disorders, pain and rheumatism. Some plants were also used for the treatment of cancer, hypertension, nerve disorders, helmenthiasis, urinary tract infections, tuberculosis, leucorrhea, edema and chicken pox. The findings of this study may help the scientists to get a comprehensive view of the folk medicinal practices in Bangladesh and can use the results to identify medicinal plants of therapeutic interests.

This present study explored the anthelmintic activities of crude methanolic extract of dried leaves and stems of Justicia gendarussa, an evergreen plant belonging to the family Acanthaceae. This plant is commonly known as Bishjarul in Bangladesh. Five concentrations (10, 20, 30, 40 and 50 mg/mL) of each extract were studied in the bioassay to determine the paralysis time and death time of the worm, Pheretima posthuma. Methanolic extract of leaves (50 mg/mL) caused paralysis of the worms at 35.3 min and death at 70.7 min while methanolic extract of stem of J. gendarussa caused paralysis at 41.3 min and death at 89.3 min. Albendazole (positive control) paralyzed and killed the worms at 17 and 48 min, respectively. The study confirms the significant anthelmintic activities of leaves and stems extract of J. gendarussa and therefore demands the isolation of active principles thorough bioassay. This is the first report of anthelmintic activities of J. gendarussa.

The present study was carried out to evaluate the antimicrobial and insecticidal activities of plant Sanchezia speciosa Hook. F. extract against pathogenic bacteria and fungi by disc diffusion method and insect by surface film activity test. Fifteen different species of Gram-positive and Gram-negative bacteria, six species of fungi and Tribolium castaneum (Herbst) insect were used for this screening. The result revealed that among the three fractions obtained by solventsolvent partitioning, chloroform fraction was the best extractive for antibacterial and antifungal properties than other two fractions (pet-ether, ethyl acetate). The ranges of zone of inhibition were 8 ± 0.01 to 23 ± 0.02 mm using 500 μg/disc. In addition the minimum inhibitory concentrations (MICs) of different solvent fractions tested were found to be in the range from 16 µg/ml to 128 µg/ml against fifteen pathogenic bacteria depending on isolates and extracting solvent. The insecticidal assay also indicated reasonable activity with 60 %, 40 % and 20 % mortality rate of Tribolium castaneum (Herbst) at a dose of 50 mg/ml in 48 hours for chloroform, ethyl acetate and petroleum ether extract respectively. This is the first report of antibacterial, antifungal and insecticidal activities of the ethanolic extract and it's fractionates (Chloroform, ethyl acetate and petroleum ether fraction) of Sanchezia speciosa Hook. F.

This study investigated the cytotoxic and anthelmintic activities of Leonurus sibiricus L.(commonly known as Raktodrone in Bangladesh) belonging to the family Labiatae. The dried leaves and roots of L. sibiricus were extracted with methanol and fractionated by modified Kupchan method. The crude methanolic extracts as well as its soluble fractions of petroleum ether, ethyl acetate and chloroform were screened for cytotoxic activity using brine shrimp lethality bioassay. They were found to possess significant cytotoxic activities. The LC 50 values of crude extract of leaves and its pet-ether, ethyl acetate and chloroform soluble fractions were 1.0, 2.0, 2.11 and1.33 µg/ml, respectively. On the other hand, the LC 50 of crude methanolic extract of roots and fractions of pet-ether, ethyl acetate and chloroform were 2.0µg/ml, 2.81 µg/ml, 3.55 µg/ml and 7.58µg/ml, respectively. Vincristine sulphate was used as positive control. The crude methanol extract of leaves and roots also showed very good anthelmintic activities as determined against the earthworms, Pheretima posthuma. The study confirms the moderate anthelmintic and potent cytotoxic activities of leaf and root extracts of L. sibiricus.

ABSTRACT:The present study was carried out to investigate the methanolic extract of leaf of Erioglossum rubiginosum and its fractionates (petroleum ether, carbontetrachloride and chloroform fractions) for their in vitro antioxidant, thrombolytic and cytotoxic activities. Among the different fractions, the carbontetrachloride soluble fraction (CTF) showed significant antioxidant activity (IC 50 =30.32±0.08 µg/ml) as compared to standard ascorbic acid (IC 50 =5.87±0.21 µg/ml) and BHT (IC 50 =27.50±0.64 µg/ml). The extract also inhibited 58.44±0.97% lipid from peroxidation and reveled excellent phenolic profile of about 128.56±1.02 mg of GAE /g of extract. In the thrombolytic assay the highest % of clot lysis was exhibited by the chloroform soluble fraction (CF) (28.57±0.83%), while for streptokinase it was about 66.77±0.92%. The LC 50 values were found within the range of 12.92 to 80.06 µg/ml, while different solvent fractions were tested for cytotoxicity against brine shrimp nauplii. This is the first report of antioxidant, thrombolytic and cytotoxic activities of E. rubiginosum.