Is dairy wastewater safe for production of edible microbial biomass: A case study of Saras dairy plant at Jaipur, India

Mismanagement of wastewater at large scale may lead to catastrophic environmental and health consequences. Microbial remediation of wastewater is one of the most effective low-cost solutions. There are also initiatives to use wastewater for production edible biomass as an alternative for protein diets. While much researches were oriented towards maximum recovery of biomass and applications, less were focused on mutagenicity of dairy wastewater. In this study, we examined wastewater of one of the largest dairy industries in Rajasthan for its suitability for microbial biomass production and mutagenicity. Influent wastewater was collected from Saras dairy plant, Jaipur, for over a week. Physiochemical properties of wastewater were examined, such as; temperature, pH, salinity, TSS, TDS, turbidity, conductivity, BOD, COD, total carbon, and total nitrogen. SOS chromotest and Salmonella fluctuation test (TA 98, TA 100 and TA 102) were carried out at variable concentration of wastewater to assess mutagenic activity. Results indicated ideal pH, temperature and salinity, for microbial remediation. High TOC and TKN were also observed in the investigated wastewater, which is few of the prerequisites for single cell production. The ratio of BOD and COD was between 0.3-0.4, making the wastewater ideal for microbial growth. No mutagenic activity was observed by SOS chromotest, all three concentrations (C 0.01, C 0.1, and C 0.2) investigated in this study were <1.5 IF. Likewise, mutagenic ratio for all three types of Salmonella revertants were below 1.2 threshold, for investigated concentrations (C 0.5, C 1, and C 10) of wastewater. Conclusively, examined influent wastewater is less likely to induce mutagenic activity at the investigated concentration. Through physiochemical analysis, the investigated wastewater assumed to be candidate substrate for microbial biomass production.

Is dairy wastewater safe for production of edible microbial biomass: A case study of Saras Dairy plant at Jaipur, India

Mismanagement of wastewater at large scale may lead to catastrophic environmental and health consequences. Microbial remediation of wastewater is one of the most effective low-cost solutions. There are also initiatives to use wastewater for production edible biomass as an alternative for protein diets. While much researches were oriented towards maximum recovery of biomass and applications, less were focused on mutagenicity of dairy wastewater. In this study, we examined wastewater of one of the largest dairy industries in Rajasthan for its suitability for microbial biomass production and mutagenicity. Influent wastewater was collected from Saras dairy plant, Jaipur, for over a week. Physiochemical properties of wastewater were examined, such as; temperature, pH, salinity, TSS, TDS, turbidity, conductivity, BOD, COD, total carbon, and total nitrogen. SOS chromotest and Salmonella fluctuation test (TA 98, TA 100 and TA 102) were carried out at variable concentration of wastewater to assess mutagenic activity. Results indicated ideal pH, temperature and salinity, for microbial remediation. High TOC and TKN were also observed in the investigated wastewater, which is few of the prerequisites for single cell production. The ratio of BOD and COD was between 0.3-0.4, making the wastewater ideal for microbial growth. No mutagenic activity was observed by SOS chromotest, all three concentrations (C 0.01, C 0.1, and C 0.2) investigated in this study were <1.5 IF. Likewise, mutagenic ratio for all three types of Salmonella revertants were below 1.2 threshold, for investigated concentrations (C 0.5, C 1, and C 10) of wastewater. Conclusively, examined influent wastewater is less likely to induce mutagenic activity at the investigated concentration. Through physiochemical analysis, the investigated wastewater assumed to be candidate substrate for microbial biomass production.

Las plantas como fuente de compuestos fotoprotectores frente al daño en el ADN producido por la radiación ultravioleta

La fotoprotección es una estrategia preventiva y terapéutica frente al cáncer y el envejecimiento de la piel. En el presente trabajo se revisan los efectos biológicos adversos de la radiación ultravioleta, los conceptos básicos relevantes de la fotoprotección y los métodos para llevar a cabo su medición. Asimismo, se resumen los resultados obtenidos de la caracterización radiobiológica y genética del modelo experimental (SOS Chromotest) usado para la bioprospección de extractos y moléculas de origen vegetal con potencial en fotoprotección. Además, se presentan datos sobre la eficacia fotoprotectora y las estimaciones del efecto antigenotóxico de aceites esenciales y extractos obtenidos de especies de plantas, así como de los compuestos mayoritarios de los aceites y extractos promisorios analizados en este estudio. Por último, se postulan posibles mecanismos de acción de algunas moléculas relevantes. Los resultados se presentan y discuten destacando su potencial uso para el desarrollo de bloqueadores solares multifuncionales.

THE EFFECT ON THE GENETIC APPARATUS OF THE MICROBIAL CELL OF COMPOUNDS BASED ON SUBSTITUTED 1H-INDOL-4-, 5-, 6-, 7-YLAMINES

The study of new antimicrobial compounds includes determining the mechanism of their effect on the microbial cell. As a rule, the effect of most modern synthetic antimicrobials is associated either with the suppression of DNA synthesis, or with the suppression of bacterial protein synthesis at the level of translation or transcription.There are sensitive and simple methods for screening and monitoring the potential genotoxic activity of a wide range of natural and synthetic compounds. To date, the Ames test has been widely used, based on the sensitivity of Salmonella strains to carcinogenic chemicals, although some compounds that cause Ames negative reactions could actually be carcinogenic to animals.Similarly, the SOS chromotest is an SOS transcriptional analysis that can evaluate DNA damage caused by chemical and physical mutagens. It measures the expression of a reporter gene (β-galactosidase). The β-galactosidase enzyme processes ortho-nitrophenyl galactopyranoside to form a yellow compound detected at 420 nm. Then, the induction of β-galactosidase normalizes the activity of alkaline phosphatase, an enzyme expressed constitutively by Escherichia coli. SOS chromotest is also widely used for genotoxicological studies. The answer is quick (several hours) and does not require the survival of the test strain. Dose response curves for various chemicals include a linear region. The slope of this area is taken as a measure of SOS induction.Therefore, an SOS chromotest was selected for the study, which allows one to identify the DNA-mediated effect of the studied compounds.The aim of the work was to evaluate the SOS-inducing activity of antimicrobial compounds based on substituted 1H-indol-4-, 5-, 6-, 7-ylamines.The strain Escherichia coli PQ 37 with the genotype F-thr leu his-4 pyrD thi galE lacΔU169 srl300 :: Th10 rpoB rpsL uvrA rfa trp :: Mis + sfi A :: Mud (Ar, lac) cts, Due to the presence of sfi A genes :: lac Z, lacZ β-galactosidase gene expression in strain PQ 37 is controlled by the promoter of the sfiA gene, one of the components of the E. coli SOS regulon. The indicator of the SOS-inducing activity of the studied compounds in the SOS chromotest is the activity of β-galactosidase, which evaluates the activity of active microorganisms - alkaline phosphatase, which also allows you to control the toxic effect of the studied compounds on bacterial cells.The results showed that 4,4,4-trifluoro-N-(6-methoxy-1,2,3-trimethyl-1H-indol-5-yl)-3-oxobutanamide (1), 4,4,4-trifluoro-N-(6-methyl-2-phenyl-1H-indol-5-yl)-3-oxobutanamide (2) and N-(1,5-dimethyl-2-phenyl-1H-indol-6-yl)-4,4,4-trifluoro-3-oxobutanamide (3) does not possess SOS-inducing activity in the studied concentrations. 4-Hydroxy-8-phenyl-4-(trifluoromethyl)-1,3,4,7-tetrahydro-2H-pyrrolo [2,3-h] -quinolin-2-one (4), 9-hydroxy-5-methyl-2-phenyl-9-(trifluoromethyl)-1,6,8,9-tetrahydro-7Н-pyrrolo-[2,3-f]quinolin-7-one (5), 6-hydroxy-2,3-dimethyl-6-(trifluoromethyl)-1,6,7,9-tetrahydro-8H-pyrrolo[3,2-h]quinolin-8-one (6) and 1,2,3,9-tetramethyl-6-(trifluoromethyl)-1,9-dihydro-8H-pyrrolo [3,2-h]quinolin-8-one (7) showed dose-dependent SOS-inducing activity in bactericidal concentrations. The obtained research results allowed us to identify compounds 4, 5, 6, 7, the mechanism of action of which includes exposure to DNA of a microbial cell.

Evaluation of the potential genotoxic activity in seawater of Asin Bay, Gulf of Gulluk, Mugla, Aegean coast of Turkey

This research examined the genotoxic activity in the seawater of Asin Bay (Gulf of Gulluk) located in Mugla, Turkey, Aegean coast of Turkey. Genotoxic activities of 66 raw samples, taken from 17 different stations in the spring and summer seasons of the year 2013, were determined by using in vitro mutagenicity assay SOS chromotest with Escherichia coli PQ37 strain bacteria activities. In the applied procedure, β-galactosidase (β-gal) activity, alkaline phosphatase (AP) activity, and different solvent controls were taken into account to generate reliable results in terms of the corrected induction factors (CIF) used as a quantitative measure of genotoxic activity level. The SOS chromotest procedure was simply and rapidly performed as an early assay to explore for whether a potential genotoxic activity was presence in the in the seawater of Asin Bay (Gulf of Gulluk) with no special measuring devices except a microplate reader. The implemented assay was successfully completed within only 24 h including the revival of the bacteria. The results showed that 11 samples (%17 of total) were close to the threshold value of 1.5. The findings of this study clearly revealed that the seawater of Asin Bay (Gulf of Gulluk) had no potential genotoxic risks in terms of the organisms in marine ecosystem, since all of the calculated CIF values were determined to be below the threshold level. It was concluded that according to the SOS chromotest results, the levels of potential genotoxic agents were found to be under the limits for the offshore fishery.

The SOS Chromotest applied for screening plant antigenotoxic agents against ultraviolet radiation

We proposed the SOS Chromotest for bioprospecting of plant genoprotective agents against UV-induced genotoxicity. The Colombian flora resulted to be a source of antigenotoxic compounds against UV.

Synthesis and Antibacterial Activity of Quaternary Ammonium 4-Deoxypyridoxine Derivatives

A series of novel quaternary ammonium 4-deoxypyridoxine derivatives was synthesized. Two compounds demonstrated excellent activity against a panel of Gram-positive methicillin-resistantS. aureusstrains with MICs in the range of 0.5–2 μg/mL, exceeding the activity of miramistin. At the same time, both compounds were inactive against the Gram-negativeE. coliandP. aeruginosastrains. Cytotoxicity studies on human skin fibroblasts and embryonic kidney cells demonstrated that the active compounds possessed similar toxicity with benzalkonium chloride but were slightly more toxic than miramistin. SOS-chromotest inS. typhimuriumshowed the lack of DNA-damage activity of both compounds; meanwhile, one compound showed some mutagenic potential in the Ames test. The obtained results make the described chemotype a promising starting point for the development of new antibacterial therapies.