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The co-substrate is a crucial component in the bio-decolorization process that helps bacteria to grow and carry out their fundamental functions. Different types of textile dyes with diverse chemical structures are frequently employed in the textile industry, and the most of them are resistant to biodegradation because of their xenobiotic nature. Due to the low carbon content of textile dyes, particularly of azo dyes, co-metabolic conditions are required for decolorization process. Hence, the current study was aimed to determine which striking carbon and nitrogen sources are preferred for generating co-metabolic conditions to decolorize the following dyes: Disperse Yellow-3, Malachite Green, Basic Red-18, and Reactive Blue-4. Different carbon and nitrogen sources were used to isolate, screen, and evaluate different bacterial strains for dye degradation. A potential bacterial strain Pseudomonas taiwanensis strain TNZ3 was identified based on 16s rDNA sequence and selected for further study. It was found that the presence of yeast, peptone, NH4Cl, sucrose, glucose, fructose, maltose, galactose, lactose, and starch in dye contaminated media effectively enhanced azo dye degradation rate by Pseudomonas taiwanensis strain TNZ3. In the medium inoculated with Pseudomonas taiwanensis strain TNZ3, sucrose and yeast with peptone extracts induced the greatest decolorization among diverse carbon and nitrogen sources. In all dyes, the maximum decolorization occurs at 1.5% yeast extract supplementation. The results made it abundantly clear that various carbon and nitrogen sources used as co-substrates played effective role on dye decolorization process.

Discharge of textile industrial effluent without proper treatment has become a severe hazard for the animal health and environment worldwide. Therefore, this study was designed to isolate azo dye-degrading bacteria from textile wastewater and evaluate their ability to biodegrade reactive dyes into non-toxic products. The potent bacterial strain which was isolated from textile wastewater was identified as Pseudomonas monteilii strain RZT1 on the basis of 16S rDNA sequence. The isolated bacterial strain exhibited good decolorization ability with yeast extract supplementation as cosubstrate in static conditions for Malachite Green dye. The optimal condition for the decolorization of Malachite Green dye by P. monteilii strain RZT1 were at pH 7.0 and 28°C. Decolorization rates of Malachite Green dye by P. monteilii strain RZT1 were varied with initial dye concentration as follow: 84.8%, 75.4%, 63.4% and 45.5% decolorization for 100ppm, 200ppm, 300ppm and 400ppm initial dye concentration respectively. We investigated the effects of dyes used in the textile industry on the seed germination of Five crops - Rice (Oryza sativa), Wheat (Triticum aestivum L.), Khesari (Lathyrus sativus), Mustard (Brassica nigra) and Bitter Melon (Momordica charantia). It was found that textile dye Malachite Green had negative effect on seed germination and seedling growth in test cultures. The harmful effects of dye on seed germination and early seedling growth parameters were augmented with increase of dye concentration. Interestingly, treatment of the Malachite Green dye with isolated bacteria reduced the adverse effects of that dye on seed germination and seedling growth. Thus, it indicated the potentiality of P. monteilii strain RZT1 for bioremediation of textile effluents into a non-toxic form for plants.

The present work reports a study on the behavior of the time series of rainfall during the summer monsoon (June–September) in northeast India. It has been observed through hypothesis testing that although a normal distribution fits the time series, no persistence forecast is possible as indicated by the low value of the Lag-1 autocorrelation coefficient (0.041). A linear regression over time is not a good fit. Subsequently, the intrinsic behavior of the time series has been explored through Hurst exponent (H) computed using rescaled range analysis. The value of the Hurst exponent is in the range of 0 < H < 0.5, and from this range, it could be understood that long-term switching is expected to exist between high and low values in adjacent pairs. However, when the Hurst exponent value is being low, the summer monsoon rainfall over northeast India has been thought of as characterized by volatility and roughness. Finally, the connectivity of the El Nino-Southern Oscillation (ENSO) to the Indian summer monsoon rainfall has been briefly discussed in light of the long-term behavior.

There is an alternative approaches from eradication of infections causes by pathogenic bacteria especially resistant bacteria. Methanol extract of Rumex vesicarius leaves were evaluated from in vitro antibacterial activity against twelve bacterial species were used which are four of them gram positive which are Streptococcus constellatus, Staphylococcus gallinarum, Staphylococcus sciuri and Streptococcus iniae and eight of them gram negative which are Aeromonas diversa, Xanthomonas campestris, Xanthomonas axonopodies, Siccibacter colletis, Edwardsielloa anguillarum, Aeromonas cavernicala, Enterobacter xiangfangenis and Vibro rotiferianus. The plant extract showed highest 12 mm zone of inhibition against Staphylococcus constellatus at the concentration of 20 μg/disc and no zone of inhibition was found from Aeromonas diversa. In minimum inhibitory concentration (MIC) test, methanol extract of Rumex vesicarious in 200μg/ml concentration showed best result against Vibrio rotiferianus. It can be concluded that methanol extracts of Rumex vesicarious leaves may be used as natural antibacterial from treatment of some diseases, especially local skin diseases.

There is an alternative approach to control the infectious diseases caused by pathogenic bacteria especially resistant bacteria. The present study was designed to determine the antimicrobial activities of Kalanchoe blossfeldiana and Paederia foetida plants extracts against some selected bacterial strains. K. blossfeldiana and P. foetida leaves were extracted in methanol. In vitro antibacterial activities were evaluated against twelve bacterial strains including, Staphylococcus gallinarum, Staphylococcus sciuri, Streptococcus constellatus, Streptococcus iniae, Aeromonas diversa, Xanthomonas campestris, Xanthomonas axonopodis, Siccibacter colletis, Edwardsiella anguillarum, Aeromonas cavernicala, Enterobacter xiangfangenis and Vibrio rotiferianus. Antimicrobial activities were screened by disc diffusion method. In addition, minimum inhibitory concentration (MIC) was determined using broth dilution method. Data were analyzed with a statistical software program (SPSS 16). In antimicrobial screening, both the plant extracts showed highest inhibition (15mm zone diameter) against Staphylococcus gallinarum at the concentration of 20μg/disc and 15μg/disc, respectively. In the MIC test, both K. blossfeldiana and P. foetida leaves extracts showed the lowest MIC value of 100μg/ml on Vibrio rotiferianus and Streptococcus iniae, respectively. From the above findings, it can be concluded that the extracts may be used as natural antibacterial agent for treatment of some bacterial diseases. Further investigations on the chemical composition and possible isolation of active ingredients are warranted.