Rajkumar Bidlan - Academia.edu (original) (raw)

Papers by Rajkumar Bidlan

Wastewater is a by-product of industrialization and urbanization processes. Developed countries g... more Wastewater is a by-product of industrialization and urbanization processes. Developed countries generate more wastewater than developing and less developed countries. Even developed countries can't treat 100% of wastewater produced. This study was aimed to investigate advanced biological methods for wastewater treatment. It reveals that biological treatment is cost effective and ecofriendly. Microbes are the best arms to combat pollutants. Metabolic engineering of microbes is the advanced strategy to optimize wastewater treatment. New microbes and their potentiality must be investigated in future. Metabolic engineering in light of biofuel production utilizing wastewater as a resource must be explored massively in future.

The study involved testing the effects of mixture of Organochlorine pesticides (Lindane and DDT) ... more The study involved testing the effects of mixture of Organochlorine pesticides (Lindane and DDT) on the germination of seeds and simultaneous bioremediation of these pesticidesby a novel microbial consortium. These two pesticides (Lindane and DDT) were selected as they are Persistent Organic Pollutants (POP), widely used in the developing economies for agricultural usage and in particular DDT which is used for mass healthcare programs thereby contributing to environmental pollution. The study was done using green gram seeds which is one of the commonly consumed legumes in India. The seed growth in presence of these pesticides exhibited a noticeable reduction in vigour index that significantly reduced withincreasing concentrations of organochlorine mixture, Lindane and DDT, at 10 ppm, 20 ppm and 30 ppm concentrations. The germination of green gram seeds was repressed upto a viguor index of 21.1on moist filter paper at 30 ppm concentrations which was evident in reduction of amylase an...

Bioscience Biotechnology Research Communications, 2017

Organochlorine pesticides are ubiquitous group of recalcitrant molecules that accumulate in food ... more Organochlorine pesticides are ubiquitous group of recalcitrant molecules that accumulate in food chains and have inherent toxic effects and adverse health effects. To circumvent the problem, microbial communities are found to be promising candidates for degrading the organochlorine pesticide's and removal of residues. In this study, a novel microbial consortium isolated from Yamuna and Godavari rivers capable of simultaneous biodegradation of organochlorine pesticides (DDT and Lindane) was subjected to metagenomic sequencing. This consortia used was enriched by progressively increasing concentrations of Lindane and DDT (organochlorine pesticides) for months till a stable Lindane and DDT tolerant population was established, and found to be degrading mixture of organochlorine pesticides with concentrations up to 30 ppm of DDT and Lindane. Currently, in the realm of our knowledge very few metagenomic analysis were carried out to characterize the consortia and understand the biodiversity of microbial communities in the riverine ecosystems, that was found to be unique and highly effi cient in bio-degradation of organochlorine pesticides. The study concluded biodiversity with a shannon alpha-diversity index of 3.0317 and identifi ed 871 species with Brevundimonas diminuta (previously assigned to the genus Pseudomanas) having abundance ratio of 17.57 % followed by Stenotrophomonas acidaminiphila in the mixed consortium and deciphered the systematic and functional contexts within riverine metagenome.

Journal of Pure and Applied Microbiology, 2017

Organochlorine pesticides (OCPs) such as Lindane and DDT (dichlorodiphenyltrichloroethane) have b... more Organochlorine pesticides (OCPs) such as Lindane and DDT (dichlorodiphenyltrichloroethane) have been extensively used for agricultural purposes primarily for pest management and DDT is still the "sought after" for public health care programs to control vector-borne diseases like malaria in developing nations. OCPs, due to recalcitrant nature slowly degrade and pose adverse health effects to the environment and community. Residues of OCPs were detected in soil, water and air leading to potential bioaccumulation in food chains and were considered persistent organic pollutants. Microorganisms were found to be potential bio-degraders of organochlorine pesticides. In this study, the microbial population from aquatic systems, rivers from Yamuna (North India) and Godavari (South India) was isolated and enriched until a Lindane and DDT tolerant population was established. Screening of the population for understanding bioremediation thresholds was done using 5ppm of DDT and Lindane. The populated microbial cells formed the consortium that was subjected to metagenomic analysis to identify the organisms till species level. The 16S amplicon sequencing identified 871 species in the consortium and established the biodiversity of the consortium. The defined consortium was able to degrade DDT and Lindane up to 30 ppm simultaneously in varying order of pesticide concentrations.

Journal of Experimental Biology and Agricultural Sciences, 2018

Organochlorine pesticides (OCPs) such as 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (p,p'-DDT... more Organochlorine pesticides (OCPs) such as 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (p,p'-DDT) and ᵧ-hexachlorocyclohexane (Lindane) pose serious health effects to the environment and community. Although both these compounds are prohibited in many parts of the world, their residues were detected in various soil, air and aquatic ecosystems. Currently, research has been carried out on a single pesticide with a single microbe or a consortium with few members for biodegradation of organochlorine pesticides. In the environment, the scenario is different with many other compounds and native flora present that can make the application of single microbe or small consortium difficult to succeed. The current study was initiated to develop a microbial consortium that can act simultaneously degrade and eliminate more than one organochlorine compounds while maintaining its integrity in the environment. In this study, the simultaneous degradation of DDT and Lindane at 10 ppm, 20 ppm and 30 ppm concentration was studied at 0, 24, 42, 78 and 92 hours at optimized conditions (pH-7 and OD600 0.075). The enriched consortium could simultaneously degrade 90% of 10 PPM of DDT and Lindane.The enriched consortium was tested for degrading mixture of organochlorine pesticides with concentrations up to 30 ppm of DDT and Lindane mixture, and demonstrated promising observations that illustrate the usage of the consortium for degrading the OCPS with high efficiency.

Bioscience Biotechnology Research Communications, 2018

Organochlorine pesticides (OCPs) primarily 1, 1, 1-trichloro-2,2-bis(4-chlorophenyl) ethane (p,p'... more Organochlorine pesticides (OCPs) primarily 1, 1, 1-trichloro-2,2-bis(4-chlorophenyl) ethane (p,p'-DDT) and -hexachlorocyclohexane (lindane) pose adverse health effects to the environment and community. Lindane and DDT (dichlorodiphenyltrichloroethane) have been broadly used for agricultural purposes. DDT is still the "sought after" for public health care programs to control vector-borne diseases like malaria in developing nations. Even though both these compounds are prohibited in many parts of the world, their residues are still found in various environmental, food, human and animal samples. In this study, the microbial population isolated from aquatic systems, rivers from Yamuna (North India) and Godavari (South India) was enriched until a Lindane and DDT tolerant population was established. Screening of the population for understanding bioremediation potential was done using 5ppm of DDT and Lindane. The populated microbial cells formed the consortium that was used subjected to metagenomic analysis to identify the organisms till species level. The 16S amplicon sequences were analysed using Kaiju online tool for establishing the identity of individual bacteria present in the mixed population. This consortium was shown to consist of 138 species with 11 uncultured bacteria with Taylorella asinigenitalis holding the maximum numbers in its population. The microbial consortium was found simultaneously degrading DDT and Lindane in shake fl asks. The enriched consortium could degrade 95% of 5 ppm lindane and 57.8% of 5 ppm DDT in the supplied mixture by the end of 72 h. This is a promising observation and the consortium shows high effi ciency in degrading the OCPs. The consortium can become a vital tool for biodegradation of organochlorine pesticides to eradicate the pesticide residues in water and soil ecosystems.

International Journal of Environmental Science and Technology, 2019

Jatropha seed cake is a by-product of biodiesel industry which is rich in proteins and carbohydra... more Jatropha seed cake is a by-product of biodiesel industry which is rich in proteins and carbohydrates and contains many bioactive compounds. Besides having a good protein quality, the essential amino acid content (except lysine) is also high in Jatropha seed cake, and therefore, Jatropha proteins can be exploited for many technical applications. The major hindrance for its use as a protein supplement is the presence of anti-nutritional factors and toxins, especially the phorbol esters. The detoxification of Jatropha seed cake for the removal of phorbol esters has been shown in our earlier studies. Proteins were extracted from the detoxified Jatropha seed cake and analyzed for amino acid content. Various parameters such as temperature, solubilization pH, precipitation pH and extraction time were studied for their effect on protein content, and the process was optimized using response surface methodology among 5 best samples selected based on protein content and protein yield from dry concentrates. The amount of dry matter, protein content and protein yield of 17.1%, 41.98% and 38.66%, respectively, was obtained under the optimized conditions of 60 °C temperature, solubilization pH 11.0, precipitation pH 4.41 and extraction time of 0.78 h. Amino acid contents revealed that the extracted samples contained a higher concentration of essential amino acids, especially leucine (4.40 ± 0.98 g/100 g). The results indicated that the protein extraction procedure from Jatropha seed cake affected the amino acid content, yet the values were close to FAO/WHO reference protein, and thus, the Jatropha proteins can be explored further for their use as feed supplement.

Bioscience Biotechnology Research Communications, 2019

International Journal of Pharmacy and Pharmaceutical Sciences, 2016

Jatropha curcas is an oilseed plant with good adaptability to grow in unfavourable conditions lik... more Jatropha curcas is an oilseed plant with good adaptability to grow in unfavourable conditions like infertile soil with scanty rainfall. It had been exploited for the extraction of oil for bio-diesel. The compressed seed cake, after the oil extraction, is a rich source of protein with certain toxic and anti-nutritional factors. The major toxins in the seed cake are phorbol esters and trypsin inhibitors that lead to various health problems if ingested. Even though the application of the various extracts carries a lot of beneficial advantages, yet the toxicity in oil and the compressed cake does not allow the by-products and the oil to be used elsewhere. Various physicochemical and biological methods have been described for the detoxification of Jatropha seed cake and oil of which the chemical extraction with methanol and ethanol have shown promising results in reducing the toxin contents by 97-100% while UV-irradiation reduced the phorbol esters completely. Submerged fermentation by Bacillus sp. achieved complete detoxification of phorbol esters within a week. A new strain was found to degrade the phorbol esters to phorbol, myristic acid and acetic acid within 12 h of incubation in submerged fermentation process. The detoxified products, in future, can be used as animal feed and food supplement to help utilize the by-products as a healthy diet.

International Journal of Current Microbiology and Applied Sciences, 2016

Research Journal of Microbiology, 2007

Process Biochemistry, 2002

Microbial degradation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT)-residues is one of t... more Microbial degradation of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT)-residues is one of the mechanisms for the removal of this compound from the environment. A DDT-degrading consortium was isolated by long term enrichment of soil samples collected from DDT-contaminated fields. This consortium was acclimated by repeated passages through a mineral salt medium containing increasing concentrations of DDT. This acclimated consortium could degrade 25 ppm of

Chemosphere, 2004

The effects of technical grade hexachlorocyclohexane (tech-HCH) on the germination of different s... more The effects of technical grade hexachlorocyclohexane (tech-HCH) on the germination of different seeds were tested. Two types of seeds, radish and green gram showed marked reduction in germination percentage and seeding vigour index. The abnormalities and reduction in germination increased with increasing concentration of tech-HCH. At 100 microg HCH level the germination of radish and green gram seeds was inhibited almost completely on moist filter paper and soil. Protease and amylase activities were reduced in seeds grown in soil spiked with tech-HCH. Bioremediation of HCH-spiked soils with a HCH-degrading microbial consortium helped in eliminating the toxic effects of tech-HCH towards seed germination. The degradation of 25 microg tech-HCH g(-1) soil was complete by 120 h. The seed germination and the activities of the assayed enzymes, amylase and protease, were same as before or better in bioremediated soils.

Dichlorodiphenyltrichloroethane (DDT) is the first synthetic compound used against pests. Though ... more Dichlorodiphenyltrichloroethane (DDT) is the first synthetic compound used against pests. Though it was first synthesised by Zeidler, the noble prize for its activity against insects especially against body lice and in control of typhus fever was awarded to Dr. Paul Muller. After the discovery that DDT can be used against insects, it was extensively used by almost all the countries for both agriculture as well as health programs. Later, it was discovered that DDT was responsible for many environmental problems viz. thinning of the eggshells in many birds especially Falcons, bringing it under the endangered category, being one among the first few hazards noticed. Today it is one of the suspect culprits for hormonal imbalance and even cancer. Its main advantage, when initially used, was its effectiveness on wide variety of insects, leading to a large-scale application on pests. However, the persistency has been now the main cause of concern to the environmentalists. Residues of DDT ha...