Geo-environmental factors and the effectiveness of mulberry leaf extract in managing malaria.

Malaria prevalence has become medically important and a socioeconomic impediment for the endemic regions, including Purulia, West Bengal. Geo-environmental variables, humidity, altitude, and land use patterns are responsible for malaria. For surveillance of the endemic nature of Purulia's blocks, statistical and spatiotemporal factors analysis have been done here. Also, a novel approach for the Pf malaria treatment using methanolic leaf extract of Morus alba S1 has significantly reduced the parasite load. The EC50 value (1.852) of the methanolic extract of M. alba S1 with P. falciparum 3D7 strain is close to the EC50 value (0.998) of the standard drug chloroquine with the same chloroquine-sensitive strain. Further studies with an in-silico model have shown successful interaction between DHFR and the phytochemicals. Both 1-octadecyne and oxirane interacted favourably, which was depicted through GC-MS analysis. The predicted binary logistic regression model will help the policy makers for epidemiological surveillance in malaria-prone areas worldwide when substantial climate variables create a circumstance favourable for malaria. From the in vitro and in silico studies, it can be concluded that the methanolic extract of M. alba S1 leaves were proven to have promising antiplasmodial activity. Thus, there is a scope for policy-driven approach for discovering and developing these lead compounds and undermining the rising resistance to the frontline anti-malarial drugs in the world.

Cloning, expression and characterization of PURase gene from Pseudomonas sp. AKS31.

Polyurethane (PUR) is a soil and aquatic contaminant throughout the world. Towards bioremediation, in a previous study, a soil bacterium, Pseudomonas sp. AKS31, capable of efficiently degrading PUR was isolated. Polyurethanase (PURase) enzyme is capable of cleaving the ester bond of PUR and is considered as a key regulator of PUR biodegradation. Hence, for a high yield, easy purification, and further characterization, the aim of this study was to clone and overexpress the PURase gene of this isolate. The current study also investigated structural aspects of this enzyme through predictive bioinformatics analyses. In this context, the PURase gene of the isolate was cloned and expressed in E. coli using pET28(a)+ vector. The obtained recombinant protein was found insoluble. Therefore, first, the protein was made soluble with urea and purified using nickel-NTA beads. The purified enzyme exhibited substantial activities when tested on the LA-PUR plate. Bioinformatics-based analysis of the protein revealed the presence of a lipase serine active site and indicated that this PURase belongs to the Family 1.3 lipase. Hence, the present study shows that active PURase can be produced in large quantities using a prokaryotic expression system and thus, provides an effective strategy for in-vitro PUR-degradation.

Pot and field studies on bioremediation of p-nitrophenol contaminated soil using Arthrobacter protophormiae RKJ100.

Biodegradation of p-nitrophenol (PNP), a priority pollutant, was studied as a model system for bioremediation of sites contaminated with nitroaromatic/organic compounds. Bioremediation of PNP-containing soil was first carried out in pots using immobilized and free cells of Arthrobacter protophormiae RKJ100 in order to ascertain the role of a suitable carrier material. Results showed that stability of the introduced strain was enhanced upon immobilization and that the rate of PNP depletion decreased with increasing depth of soil. Small-scale field studies (in one square meter plots) were then conducted in which PNP-contaminated soil from an agricultural field was bioaugmented with strain RKJ100 under natural environmental conditions. PNP was totally depleted in 5 days by immobilized cells, whereas free cells were able to deplete 75% of PNP in the same time period. The fate of the released strain as monitored by plate counts, hybridization studies, and real-time polymerase chain reaction revealed fairly stable population of the cells upon immobilization on corncob powder throughout the period of study.