Microbiology

In the present study, combinations of Distillery Waste (DW) with other industrial wastes viz. curd Whey Waste (WW), Fruit Processing Waste (FPW) and Sugar Industry Effluent (SIE) were evaluated to replace the use of water that was reported earlier for biosurfactant production from 1: 3 diluted distillery waste by using four new bacterial cultures BS-A, BS-J, BS-K and BS-P, isolated from soil collected from a distillery unit. These isolates have the potential to produce biosurfactant from these individual wastes and in their combinations. Highest biomass and biosurfactant yields with higher reduction in the Chemical Oxygen Demand (COD), total sugars, nitrogen and phosphate levels were obtained in 1:1:1 proportion of DW+WW+FPW followed by DW+WW+ SIE and individual wastes. The combinations of wastes improved the yields of biosurfactants by 18-41% and reduced COD of the combined wastes by 76-84.2%. Total sugars, nitrogen and phosphate levels reduced in the range of 79-86%, 58-71% and 45-59%, respectively. Among the four microbial isolates tested, BS-J and BS-P were the efficient biosurfactant producers and were identified as Kocuria turfanesis and Pseudomonas aeruginosa based on the 16S rDNA sequence and phylogenetic analyses. Benefits derived by using combined distillery waste with other wastes are improved production of biosurfactant as resource and saving precious water and the costly nutrients with concomitant reduction in pollution load of the wastes.

An unconventional nutrient medium, distillery spent wash ((1:3) diluted) was used to produce di-rhamnolipid biosurfactant by Pseudomonas aeruginosa strain BS2. This research further assessed the potential of the biosurfactant as a washing agent for metal removal from multimetal contaminated soil (Cr-940 ppm; Pb-900 ppm; Cd-430 ppm; Ni-880 ppm; Cu-480 ppm). Out of the treatments of contaminated soil with tap water and rhamnolipid biosurfactant, the latter was found to be potent in mobilization of metal and decontamination of contaminated soil. Within 36 hours of leaching study, di-rhamnolipid as compared to tap water facilitated 13 folds higher removal of Cr from the heavy metal spiked soil whereas removal of Pb and Cu was 9-10 and 14 folds higher respectively. Leaching of Cd and Ni was 25 folds higher from the spiked soil. This shows that leaching behavior of biosurfactant was different for different metals. The use of wastewater for production of biosurfactant and its effi cient use in metal removal make it a strong applicant for bioremediation.

Methods used for biosurfactant recovery include solvent extraction, precipitation, crystallization, centrifugation and foam fractionation. These methods cannot be used when distillery wastewater (DW) is used as the nutrient medium for biosurfactant production by Pseudomonas aeruginosa strain BS2, because recovery of biosurfactant by any of these methods imparts color to the biosurfactant. The biosurfactant has a nonaesthetic appearance with lowered surface active properties. These methods cannot be used for continuous recovery of biosurfactant during cultivation. Hence, a new downstream technique for biosurfactant recovery from fermented DW comprised of adsorption-desorption processes using wood-based activated carbon (WAC) was developed. This study involves batch experiments to standardize the factors affecting the rate of biosurfactant adsorption onto WAC. WAC was the most efficient adsorbent among various ones tested (i.e., silica gel, activated alumina and zeolite). The WAC (1% w v-1), equilibrium time (90 min), pH range of 5-10 and temperature of 40°C were optimum to achieve 99.5% adsorption efficiency. Adsorption kinetics and intraparticle diffusion studies revealed the involvement of both boundary layer diffusion and intraparticle diffusion. The Langmuir adsorption isotherm of WAC indicated the formation of a monolayer coverage of the biosurfactant over a homogeneous carbon surface, while the Freundlich isotherm showed high adsorption at strong solute concentrations and low adsorption at dilute solute concentrations. WAC concentration of 4% w v-1 facilitated complete removal of the biosurfactant from collapsed foam (contained 5-fold higher concentration of biosurfactant than was present in fermented DW). Biosurfactant adsorption was of chemisorption type. Acetone (polar solvent) was a specific viable eluant screened among various ones tested because it selectively facilitated maximum recovery, i.e., 89% biosurfactant from WAC. By acetone treatment, complete regeneration of WAC was feasible and WAC can be reused for biosurfactant recovery up to 3 cycles. The recovered biosurfactant showed improved surface-active property (i.e., much lower critical micelle concentration value of 0.013 verses 0.028 mg mL-1 for biosurfactant recovered by classical methods). The reuse potential of WAC was assessed and results suggest that the carbon can be reused for three consecutive cycles for biosurfactant adsorption from fermented wastewater without any decrease in adsorption efficiency. Thus, this process forms a basis for continuous recovery of biosurfactant from fermented DW and concentrated foam. This process reduces the use of high cost solvent, avoids end product inhibition and minimizes product degradation.

Surface-active potential of biosurfactants produced cost-effectively in curd whey by Pseudomonas aeruginosa strain-PP2 and Kocuria turfanesis strain-J were tested using parameters viz. surface tension (ST) reduction, F(CMC) (highest dilution factor to reach critical micelle concentration) and emulsification index (EI-24) of pesticides; monocrotophos and imidacloprid at extreme environmental conditions. Results have shown that ST reduction of biosurfactants was stable at pH 2-11. High F(CMC) of the biosurfactant in the fermented whey at low pH improved emulsification of pesticides. ST marginally increased at 5% and 15% NaCl, resulting in high EI-24 and F(CMC). Over a range of temperatures 30-121 °C, ST remained low with a higher F(CMC) and EI-24 at 60 °C than at 121 and 30 °C. The biosurfactants have shown differences in their surface-active property and have marked specificity to emulsify pesticides in extreme environmental conditions.

In the present study, combinations of Distillery Waste (DW) with other industrial wastes viz. curd Whey Waste (WW), Fruit Processing Waste (FPW) and Sugar Industry Effluent (SIE) were evaluated to replace the use of water that was reported earlier for biosurfactant production from 1: 3 diluted distillery waste by using four new bacterial cultures BS-A, BS-J, BS-K and BS-P, isolated from soil collected from a distillery unit. These isolates have the potential to produce biosurfactant from these individual wastes and in their combinations. Highest biomass and biosurfactant yields with higher reduction in the Chemical Oxygen Demand (COD), total sugars, nitrogen and phosphate levels were obtained in 1:1:1 proportion of DW+WW+FPW followed by DW+WW+ SIE and individual wastes. The combinations of wastes improved the yields of biosurfactants by 18-41% and reduced COD of the combined wastes by 76-84.2%. Total sugars, nitrogen and phosphate levels reduced in the range of 79-86%, 58-71% and 45-59%, respectively. Among the four microbial isolates tested, BS-J and BS-P were the efficient biosurfactant producers and were identified as Kocuria turfanesis and Pseudomonas aeruginosa based on the 16S rDNA sequence and phylogenetic analyses. Benefits derived by using combined distillery waste with other wastes are improved production of biosurfactant as resource and saving precious water and the costly nutrients with concomitant reduction in pollution load of the wastes.

The ability of the biosurfactant producing Kocuria turfanesis to mineralize monocrotophos was investigated through an experimental set up using different treatments of soil with carrier based bioaugmentation package of egg shell coated with biosurfactant and biosurfactant producing microbial isolates BS-J cells. Dual capabilities of biosurfactant production and degradation of monocrotophos are the two main attributes of strain BS-J which was isolated from lube oil and distillery spent wash contaminated soil collected from a distillery unit. On the basis of the cellular morphology, physiological and chemotaxonomic characteristics and phylogenetic similarity of 16S rDNA gene sequences, the strain BS-J was identified as a Kocuria turfanesis. Present study has shown that degradation of monocrotophos in contaminated soil was facilitated after using carrier based bioaugmentation package of egg shell coated with biosurfactant producing microbial isolate BS-J cells and its biosurfactant resulted 86-89 % degradation of monocrotophos after 7-days of treatment. Without biosurfactant producing microbial cells the degradation of pesticide was comparatively lower indicating the need of live biosurfactant producing microbial cells and their surfactants for efficient degradation of pesticide. Results indicate that Kocuria turfanesis strain BS-J has great potential utility for the bioremediation of soil contaminated with monocrotophos.

Pseudomonas aeruginosa strain BS2 has been demonstrated to have an ability to produce potent biosurfactant, an ecofriendly substitute to synthetic surfactants from distillery and whey wastes and capable of reducing the pollution load of these wastes in the range of 85-90%. To determine the basis for future identification of the genes responsible for biosurfactant production from wastes, studies on the presence of plasmid if any, its profile and role in biosurfactant production were performed. Suitable plasmid screening technique was selected because strain BS2 produced excessive slime in Luria Burnetti broth, which interfered with the migration and detection of plasmid. Among the several methods, alkaline lysis method was the most suitable which aided in recovery of slime-free cell lysate and resulted in the formation of a discrete band of plasmid in agarose gel. Plasmid profile study demonstrated that plasmid had high molecular weight of 32.08×10 6 Da and possessed the genetic determinants for antibiotics (chloramphenicol, tetracycline and sulphonamide) and heavy metal salt (mercuric chloride) resistance and were used as markers in curing experiment. To determine the role of megaplasmid in biosurfactant production, curing of megaplasmid was performed at highest sublethal doses of acridine orange (100 g/ml) and mitomycin-C (15 g/ml). Results indicated that only mitomycin-C treatment resulted in 28% of cell population which turned sensitive towards marker antibiotics and heavy metal salt due to loss of megaplasmid, which was further confirmed by agarose gel electrophoresis. Comparative analysis of biosurfactant production potential of cured cells with that of wild cells in both the wastes showed that the cured cells had similar potential capability of biosurfactant production as of wild strain which illustrates that genes responsible for biosurfactant production in distillery and whey wastes utilizing strain BS2 were not plasmid borne but resided on the chromosome where they are more stable.

Tuberculosis is the world wide problem and a major health issue in India, especially due to emergence of Multi Drug Resistance (MDR) strains of Mycobacterium tuberculosis. A total of 112 respiratory specimens comprising of 54 sputum, 42 bronchial aspirates and 16 pleural fluids were tested for tuberculosis by ZiehlNeelson staining (ZN), culture and Line Probe Assay (LPA), a Polymerase Chain Reaction (PCR) based rapid test. M. tuberculosis was detected in 48 (42.86%) samples in which ZN stain was positive in 28 (25.00%), culture in 39 (34.82%) and LPA in 48 (42.86%) samples. All these tests were simultaneously positive in 27 (56.25%) of 48 positive samples, any two tests positive in 13 (27.08%) and only LPA positive in 8 (16.67%) samples. MDR was observed in 5 out of 39 (12.82%) culture positive samples and 6 out of 48 (12.5%) LPA positive samples. ZN stain sensitivity is low and culture is time consuming. LPA is most sensitive test, it is rapid and can be used for diagnosis of tuberculosis and detection of MDR as well in a single test run.

MDR cases of tuberculosis are increasing and they are difficult to treat. This study was conducted to assess prevalence of drug resistance in Mycobacterium tuberculosis. Study comprises of 67 sputum specimen received for Mycobacterium tuberculosis (MTB) culture. Culture was done in Middlebrook broth using BacT Alert 3D automated culture system. The study period was from Dec 2018 to Nov 2019. Out of these MTB was grown in 31 (46.27%) cases. The first line sensitivity testing was done in liquid culture media (BacT Alert3D) against Isonizid, Rifampicin, Ethambutol, Streptomycin. Isonizid and Rifampicin resistance was seen in 3 (9.68%) cases. Only Isonizid resistance was seen in 9 (29.03%) cases. This indicates that multidrug resistance is present to the tune of 9.68 % while monoresistance to isonizid is more common in 29.03%. Monoresistance to rifampicin was not observed. Resistance to ethambutol and streptomycin was not observed in the present study. The advantage of doing Drug susceptibility testing in liquid media over solid media is speed and the results can be obtained within 15 days as compared to over 4 weeks when tested in solid media. Rifampicin resistance can be considered as a marker for labeling the strain as MDR.

An unconventional nutrient medium, distillery spent wash ((1:3) diluted) was used to produce di-rhamnolipid biosurfactant by Pseudomonas aeruginosa strain BS2. This research further assessed the potential of the biosurfactant as a washing agent for metal removal from multimetal contaminated soil (Cr-940 ppm; Pb-900 ppm; Cd-430 ppm; Ni-880 ppm; Cu-480 ppm). Out of the treatments of contaminated soil with tap water and rhamnolipid biosurfactant, the latter was found to be potent in mobilization of metal and decontamination of contaminated soil. Within 36 hours of leaching study, di-rhamnolipid as compared to tap water facilitated 13 folds higher removal of Cr from the heavy metal spiked soil whereas removal of Pb and Cu was 9-10 and 14 folds higher respectively. Leaching of Cd and Ni was 25 folds higher from the spiked soil. This shows that leaching behavior of biosurfactant was different for different metals. The use of wastewater for production of biosurfactant and its effi cient use in metal removal make it a strong applicant for bioremediation.

Pseudomonas aeruginosa strain BS2 has been demonstrated to have an ability to produce potent biosurfactant, an ecofriendly substitute to synthetic surfactants from distillery and whey wastes and capable of reducing the pollution load of these wastes in the range of 85-90%. To determine the basis for future identification of the genes responsible for biosurfactant production from wastes, studies on the presence of plasmid if any, its profile and role in biosurfactant production were performed. Suitable plasmid screening technique was selected because strain BS2 produced excessive slime in Luria Burnetti broth, which interfered with the migration and detection of plasmid. Among the several methods, alkaline lysis method was the most suitable which aided in recovery of slime-free cell lysate and resulted in the formation of a discrete band of plasmid in agarose gel. Plasmid profile study demonstrated that plasmid had high molecular weight of 32.08×10 6 Da and possessed the genetic determinants for antibiotics (chloramphenicol, tetracycline and sulphonamide) and heavy metal salt (mercuric chloride) resistance and were used as markers in curing experiment. To determine the role of megaplasmid in biosurfactant production, curing of megaplasmid was performed at highest sublethal doses of acridine orange (100 g/ml) and mitomycin-C (15 g/ml). Results indicated that only mitomycin-C treatment resulted in 28% of cell population which turned sensitive towards marker antibiotics and heavy metal salt due to loss of megaplasmid, which was further confirmed by agarose gel electrophoresis. Comparative analysis of biosurfactant production potential of cured cells with that of wild cells in both the wastes showed that the cured cells had similar potential capability of biosurfactant production as of wild strain which illustrates that genes responsible for biosurfactant production in distillery and whey wastes utilizing strain BS2 were not plasmid borne but resided on the chromosome where they are more stable.

The ability of oxindolimine copper(II) and zinc(II) complexes, known to have antitumor activity, to inhibit human topoisomerase IB has been tested through enzymatic kinetic assays and molecular docking simulations. These copper and zinc compounds are able to inhibit remarkably the cleavage reaction and only partially the religation step, the copper compound being more efficient than the zinc one. A complete inhibition activity of the cleavage is only obtained when the enzyme is pre-incubated with the compound, the inhibition being irreversible and reversible for the copper and zinc compounds, respectively. The relative stability of such complexes was estimated by competitive equilibria with human serum albumin (HSA), monitored by CD spectroscopy. The copper species shows a log K CuL = 17.2, while the analogous zinc complex exhibits a log K ZnL = 7.2. Molecular docking simulation studies show that the almost square planar geometry of the copper compound allows a direct coordination of the metal with two amino acids (Glu492, Asp563) of the enzyme at variance of the zinc compound which has a more tetrahedral geometry.

A gold(III) compound [Au(C^N^C)(IMe)]CF(3)SO(3) (Gold III) has been reported to have anticancer properties as it is able to reduce topoisomerase IB activity in vitro and suppress tumor growth in nude mice model. Here we have investigated the mechanism of inhibition of human topoisomerase IB activity by this compound, analyzing the various steps of the catalytic cycle. DNA supercoiled relaxation and the cleavage reaction are inhibited, but Gold III does not perturb the religation reaction, in contrast to what has been observed for camptothecin. Pre-incubation of enzyme with the inhibitor before adding DNA substrate increases the inhibitory effect. In addition, when Gold III is preincubated with the enzyme it prevents the stabilization of the cleavable complex by camptothecin. The analysis of the DNA-topoisomerase binding reaction indicates that the compound acts as a topoisomerase I inhibitor by preventing the enzyme-DNA interaction.

The chlorinated cyclic sulphite diester endosulfan is a broad spectrum insecticide that has been used extensively for over 30 years on a variety of crops. Endosulfan is often classified as a cyclodiene and has the same primary action and target site as the other cyclodiens 1. However, it has chemical and physical properties significantly different from other cyclodienes insecticide that affects both its environmental and biological fates. The aim of this research work is the investigation of an enzymatic Method for endosulfan degradation. Enzymatic degradation for pesticide is receiving serious attention as an alternative to existing methods, such as incineration and landfill. In particular, enzymatic insecticide bioremediation is the focus of extensive study after the isolation of enzymes capable of detoxifying a range of organophosphate compounds from several bacterial species. An essential step in the investigation of an enzymatic method for endosulfan degradation is the definitive identification of a biological source of endosulfan degrading activity.

Urinary tract infection (UTI) is one of the commonest hospital acquired infection. It encompass a spectrum of clinical and pathological conditions involving various parts of the urinary tract. Despite treatment with antimicrobial agents, urinary tract infections are often recurrent. Either there is reinfection with a different micro-organism or recurrence of bacteriuria with the same organism that was originally isolated. A wide range of anti-microbials has been used to treat urinary tract infections. There is an increase in bacterial resistance in most patients and several infections have often proved to be therapeutically problematic. In recent times complementary and alternative medicine has taken an important role in treatment of various diseases. The objective of this study is to evaluate the antibacterial potential of the Asparagus racemosus ( Satawari ) on various multidrug resistant clinical isolates Four different extracts of Asparagus racemosus ( Satawari ) were screened for their antibacterial activity against multidrug resistant bacterial strains from patients with UTI. Aqueous, ethanolic, methanolic and ethyl acetate extracts of Asparagus racemosus ( Satawari ) were tested for antimicrobial activity in vitro by the agar well diffusion method. The minimum inhibitory concentration (MIC) of the effective extract was determined by the agar dilution method. Ethanolic extract of A. racemosus shown significant in vitro antibacterial activity against E. coli, Salmonella spp. as well as Pseudomonas aeruginosa while it is ineffective against Streptococcus spp. and S.aureus. Aqueous extract was found to be effective against both Gram positive as well as gram negative uropathogens. This extract is effective against Streptococcus spp., S.aureus spp., Salmonella spp., E. coli as well as Pseudomonas aeruginosa. Similarly, methanolic extracts result is also broad spectrum and showing activity towards gram positive as well as gram negative uropathogens. Similarly, ethyl acetate extract efficacy towards Salmonella spp., E. coli, Pseudomonas aeruginosa as well S.aureus but, it is ineffective against Streptococcus isolates. Result of antimicrobial assay reveals that methanolic and aqueous extract of plant exhibited broad spectrum activity against tested isolates as compared to ethanolic and ethyl acetate extract. This indicates that involvement of more than one active principles of biological significance. The herb A. racemosus is a safe drug with antimicrobial potential and without any known adverse effect might be an alternative to antibiotics during UTI infections.

The present study was carried out to evaluate antibacterial activity of toothpastes, which were available in local market. A total 15 samples were collected for isolation of cariogenic bacteria. The bacterial strains were isolated by using selective Medias and identified on the basis of cultural, morphological, biochemical characteristics. The bacterial strains resistant to various choosen antibiotics subjected to action of toothpaste. Aqueous solutions of toothpastes were tested against dental caries bacteria. The distilled water suspension of toothpastes were found to has remarked antibacterial properties.in the current study total 7 brands of toothpastes used and labeled as T1-T7.The effectiveness of toothpaste was reported based on zone of growth inhibition against cariogenic bacteria. Toothpastes T3and T7 showin g broad spectrum of action against antibiotic resistant strains of Pseudomonas spp, Streptococcus spp., Staphylococcus aureus. And Lactobacillus spp.T1 is also effectiv...

Concrete being the foremost building material broadly used in the construction sector is subjected to crack formation due to low tensile strength, durability, and ductility. So this issue is of great curiosity to the researchers in pursuit for the concrete production with better properties. Micro-cracks are the main reason for structural failure occurs, when the load applied exceeds its limits. This causes the seepage of water and other salts. In order to overcome this, the carbonate precipitating, non-pathogenic, sporeforming, alkaline resistant strain of Bacillus subtilis has been explored as a bio-cementing material. Cracks in M20 grade concrete blocks are injected by direct means with screened bacterial strain Bacillus subtilis (BH3) at the cell concentration of 10 4 , 10 5 , 10 6 CFU/ml with silica gel as an immobilizing agent and calcium lactate as a food source. The cracks were allowed to heal for appropriate time duration at specific pH, temperature, and urea concentration. These findings suggest the potential of Bacillus subtilis in an autogenously healing process.