Volume 18, Issue 4, 2018 October-December

Volume 18, No 4 Pages:
2018 October-December Articles: 4

Phytochemical screening and evaluation of antidepressant activity of methanolic extract of the spadix of Colocasia affinis Schott

The objective of this study was to determine the phytoconstituents present in successive extracts and the antidepressant activity of methanolic extract of the spadix of Colocasia affinis. The preliminary phytochemical investigation indicated the presence of fats and fixed oils, steroids and triterpenoids in petroleum ether extract, steroids and triterpenoids in chloroform extract, flavonoids and tannins in methanol extract and carbohydrates in the aqueous extract. An in vivo test for antidepressant activity was performed on the methanolic extract of the plant at two different doses using force swim test and tail suspension test on an experimental animal model (rat). Imipramine was used as a standard drug for the study. The methanolic extract at 200 and 400 mg/kg, produced significant reduction (p<0.001) in the immobility period when compared with that of control group animals in both the tests. Thus, the result indicates that the methanolic extract exhibited significantly good antidepressant activity. Further investigation may be needed to understand the actual mechanism of action.

Isolation and molecular characterization of ginger soft rot pathogenic fungi in Aizawl district of Mizoram, India

Ginger soft rot disease caused by fungal pathogens have become one of the most serious problems causing reduced production around the world. It has also caused a major problem among farmers of Mizoram state in India resulting in a huge decline in rhizome yield. However, the exact causative agents of this disease have not been identified in the state. Therefore, the present study was undertaken to isolate and characterized the causative agents of ginger soft rot disease from the diseased plants collected from five different villages of Aizawl district, Mizoram. Isolated fungi were cultured and morphological and molecular identification were done using internal transcribed spacer of rDNA. Fusarium oxysporum, F. solani and Plectosphaerella cucumerina were identified in ginger samples from five villages. Fusarium spp. were the most common and seem to be the major causative agents. It is suggested that further investigation is required to explore the diversity of ginger soft rot pathogenic fungi in the whole state which could be helpful in introducing effective and eco-friendly disease management programme.

Some phytochemical analyses of different extracts of the cogon grass Imperata cylindrica from Mizoram, India

Cogon grass, Imperata cylindrica (L.) Räuschel, was studied for its flavonoid and phenol contents. A series of extracts of the underground (rhizome-root) parts was prepared by hot extraction using solvents of different polarities such as chloroform, methanol, and petroleum ether. The total flavonoid content of the plant extracts was determined based on the reaction with aluminum chloride, sodium nitrite, and sodium hydroxide. Quercetin was used as a standard reference. Chloroform extract showed highest content of flavonoids with 30.88 mg QE/g dry wt., followed by petroleum ether extract which was 22.05 mg mg QE/g dry wt., and methanol extract has the least value with 7.35 mg QE/g dry wt. The total phenolic content of the plant was estimated based on the reaction of Folin-Ciocalteu reagent using gallic acid as the standard reference. Again, the chloroform extract had the highest content with 7.54 mg GAE/g dry wt., while methanol extract contained 5.03 mg GAE/g dry wt., and petroleum ether extract contained 3.63 mg mg GAE/g dry wt. Our study shows that I. cylindrica is a good source of antioxidants.

Diversity, distribution and conservation status of fish of the genus Garra (Cypriniformes: Cyprinidae) from the Kaladan drainage of Mizoram, northeastern India

The present study was carried out on the diversity of fish under the genus Garra from the Kaladan River and its tributaries of Mizoram, northeast India. The study reported the occurrence of seven species viz. Garra flavatra, G. cf. koladynensis, G. cf. matensis, G. nigricolis, G. rakhinica, G. manipurensis and G. khawbungi. Key to Garra species from Kaladan River drainage of Mizoram and their brief descriptions are given.