Nargis Sultana Chowdhury is a PhD student of pharmacy department of Jahangirnagar University and Doctoral fellow of Bangladesh Council of Scientific and Industrial Research (BCSIR) Laboratories, Dhaka, Bangladesh. Chowdhury received her B.Pharm and M.Pharm degree from Jahangirnagar University, Dhaka, Bangladesh. Her primary research interests are in the field of natural products. She has published more than 15 papers in reputed international and national journals. She is working as an assistant professor in Manarat International University in the department of pharmacy, Dhaka, Bangladesh.
There is a general call for new antibiotics and chemotherapeutic agents that are highly effective and possess low toxicity. Plants and microorganisms, being the major source of many drugs, have attracted scientists from ancient times. Endophytes provide an abundant reservoir of bioactive metabolites for medicinal exploitation, and an increasing number of novel compounds are being isolated from endophytic fungi. This study was conducted to characterize and explore the bioactive metabolites from two aquatic plants of Bangladesh namely Monochoria hastata (L.) Solms and Aponogeton undulatus Roxb. as well as their associated endophytic fungi. Extracts from the plants and endophytic fungi were screened for bioactivities followed by isolation and characterization of the active constituents by various chromatographic and spectroscopic methods.rnrnPreliminary screening of crude extracts from plants and endophytic fungi showed significant bioactivities and revealed the presence of interesting metabolites (1,2,3,4,5 and 6).
Nazia Hoque is a PhD student of Centre of Natural Product Research, Department of Pharmacy, Jahangirnagar University, Dhaka, Bangladesh. She has completed her MS in Pharmaceutical science and B. Pharm from the same institution. She is now working as a senior Lecturer in the Department of Pharmacy, East West University, Dhaka, Bangladesh.
The objective of the study was to evaluate the presence of different phytoconstituents and investigate in vitro bioactivities of pet ether extract, chloroform extract and methanol extract of Thysanolaena maxima available in Bangladesh. Phytochemical screening was conducted using specific standard procedure. Antioxidant activity of the extracts was evaluated using DPPH radical scavenging assay, determination of total phenolic content, determination of total flavonoid content and reducing power assay. Antibacterial and cytotoxic activities were investigated using disc diffusion method and brine shrimp lethality bioassay respectively. The methanol extract of T. maxima showed the highest DPPH radical scavenging activity and highest phenolic content (IC50 value for DPPH is 37.76 μg/ml and total phenolic content is 74.39±2.87 in mg/g, Gallic acid equivalents) compared to the pet ether and chloroform extract. On the other hand, chloroform extract posses maximum flavonoid content (81±7.542 in mg/g, Quercetin equivalents) and highest reducing power compare to other extracts. In antibacterial study, all the extracts showed mild to moderate activity against 5 gram positive and 6 gram negative bacteria with zone of inhibition ranging from 7 mm to 15 mm. In Brine shrimp lethality bioassay, the LC50 values for pet ether, chloroform and methanol extract were 1351.9 μg/ml, 975.61 μg/ml and 1136.74 μg/ml respectively which revealed very weak cytotoxic potential of the extracts. The results indicate that T. maxima could be a very potent source of natural radical scavenger and antimicrobial agents. Further studies are needed to be conducted to identify the compounds responsible for producing such bioactivities.