Efficacious use of potential biosurfactant producing plant growth promoting rhizobacteria to combat petrol toxicity in Zea mays L. plants.

Soil pollution caused by petroleum hydrocarbons is a serious threat for human life, as it affects the groundwater, cause economical losses after decreasing the agricultural production, and create other ecological issues. Here, we are reporting the isolation and screening of rhizosphere bacteria possessing biosurfactant producing potential and capable of enhancing plant growth under petrol stress as well as possessing. Efficient biosurfactant producers having plant growth promoting traits were characterized morphologically, physiologically, and phylogenetically. These selected isolates were identified as Bacillus albus S2i, Paraclostridium benzoelyticum Pb4, and Proteus mirabilis Th1 based on 16S rRNA sequence analysis. These bacteria possessed plant growth promoting attributes as well as exhibited positive activity toward the assays based on hydrophobicity, lipase activity, surface activity, and hydrocarbon degradation that indicated the production of biosurfactants. Fourier transform infrared spectroscopy of crude biosurfactants extracted from bacterial strains revealed that the biosurfactants from Pb4 and Th1 might belong to glycolipid or glycolipopeptide class whereas the biosurfactants from S2i could be from phospholipid class. Scanning electron micrographs exhibited group of exopolymer matrices interconnecting the cells forming a complex network of mass, while energy dispersive X-ray analysis has shown elemental composition of biosurfactants with dominance of nitrogen, carbon, oxygen, and phosphorous. Further, these strains were then used to ascertain their effect on the growth and biochemical parameters including stress metabolites and antioxidant enzymology of Zea mays L. plants grown under petrol (gasoline) stress. Significant increments in all studied parameters were observed in comparison with control treatments that might be due to petrol degradation by bacteria and also by secreting growth stimulating substances released by these bacteria in soil ecosystem. To the best of our knowledge, this is the first report in which Pb4 and Th1 were studied as surfactant producing PGPR and further their role as biofertilizer for the significant improvement in phytochemical constituents of maize plants grown under petrol stress was assessed.

A novel RdRp-based colorimetric RT-LAMP assay for rapid and sensitive detection of SARS-CoV-2 in clinical and sewage samples from Pakistan.

Novel corona virus SARS-CoV-2, causing coronavirus disease 2019 (COVID-19), has become a global health challenge particularly for developing countries like Pakistan where overcrowded cities, inadequate sanitation, little health awareness and poor socioeconomic conditions exist. The SARS-CoV-2 has been known to spread primarily through direct contact and respiratory droplets. However, detection of SARS-CoV-2 in stool and sewage have raised the possibility of fecal-oral mode of transmission. Currently, quantitative reverse-transcriptase PCR (qRT-PCR) is the only method being used for SARS-CoV-2 detection, which requires expensive instrumentation, dedicated laboratory setup, highly skilled staff, and several hours to report results. Considering the high transmissibility and rapid spread, a robust, sensitive, specific and cheaper assay for rapid SARS-CoV-2 detection is highly needed. Herein, we report a novel colorimetric RT-LAMP assay for naked-eye detection of SARS-COV-2 in clinical as well as sewage samples. Our SARS-CoV-2 RdRp-based LAMP assay could successfully detect the virus RNA in 26/28 (93%) of RT-PCR positive COVID-19 clinical samples with 100% specificity (n = 7) within 20 min. We also tested the effect of various additives on the performance of LAMP assay and found that addition of 1 mg/ml bovine serum albumin (BSA) could increase the sensitivity of assay up to 101 copies of target sequence. Moreover, we also successfully applied this assay to detect SARS-CoV-2 in sewage waters collected from those areas of Lahore, a city of Punjab province of Pakistan, declared as virus hotspots by local government. Our optimized LAMP assay could provide a sensitive first tier strategy for SARS-CoV-2 screening and can potentially help diagnostic laboratories in better handling of high sample turnout during pandemic situation. By providing rapid naked-eye SARS-CoV-2 detection in sewage samples, this assay may support pandemic readiness and emergency response to any possible virus outbreaks in future.

Enhanced visible light photocatalytic activity of TiO2 co-doped with Fe, Co, and S for degradation of Cango red.

The photocatalytic activity of TiO2 was enhanced under visible light when it was co-doped with Fe, Co, and S through the sol-gel method. The resultant nano photocatalysts were characterized by XRD, EDX coupled with SEM, FT-IR, UV-Vis, and UV-DRS. The concentration ratio of precursor salts of Fe and S was kept at 1% each and of Co varied between 0.5% -1.5%. The photodegradation of Congo red was carried out and various factors like the concentration of catalyst, initial concentration of dye, pH, and irradiation time were also investigated to optimize the degradation process. Under optimized degradation conditions, 99.3% of Congo red (30 ppm) was degraded at slightly acidic pH, with 0.14 g of photocatalyst within 70 min of irradiation time.