The 3,4-dihydroxy phenyl L-alanine (L-dopa) is a drug of choice for Parkinson's disease, controlling changes in energy metabolism enzymes of the myocardium following neurogenic injury. Aspergillus oryzae is commonly used for L-dopa production; however, potential improvements in ease of handling, growth rate and environmental impact have led to an interest in exploiting alternative yeasts. The two important elements required for L-dopa production are intracellular tyrosinases (thus pre-grown yeast cells are required for the transformation of L-tyrosine to L-dopa) and L-ascorbate, which acts as a reducing agent.

Farmers near towns and cities are using a wide range of highly polluted wastewaters for crop irrigation in Pakistan due to severe freshwater shortage. The present study aimed to promote indigenous bacterial strains isolated from domestic, hospital, textile, pharmaceutical and mixed wastewaters to remove contaminants and colour and render these wastewaters safer for irrigation. Thirty seven bacterial strains were isolated from five wastewater samples collected from different sites in Lahore, Pakistan. Under optimal growth conditions, three isolates (D6, D7 and P1) showed >93% decolourisation potential in the treatment of hospital wastewater. 16S rDNA sequencing identified two of these isolates (D6 and D7) as showing 100% and 99.86% homology to Bacillus paramycoides spp. – novel strains from B. cereus group. Isolate P1 showed 97.47% homology to Alcaligenes faecalis. GCMS analysis of the untreated hospital wastewater revealed the presence of pharmaceutic pollutants, i.e. Phenol (876 µg/L), Salicylic acid (48 µg/L), Caffeine (7 µg/L), Naproxen (23 µg/L), Octadecene (185 µg/L) and Diazepam (14 µg/L). The analysis of treated hospital wastewaters showed percentage degradation of pharmaceutic pollutants (100%–43%) and significant reduction in the BOD₅ (91%–68%), COD (89%–52%) and heavy metals concentrations. These strains therefore can represent a low-cost and low-tech alternative to bioremediate complex matrices of hospital wastewater prior to crop irrigation to support the achievement of clean re-usable water in developing countries like Pakistan. GRAPHICAL ABSTRACT

The spent black tea extract was utilized in order to synthesize the spent black tea silver nanoparticles (SBT-AgNPs). Various parameters were tested to yield the best production of SBT-AgNPs. The characterization was conducted by X-Ray diffraction, Scanning electron microscopy, Zeta potential and energy dispersive X-ray (EDX). The XRD analysis showed hkl planes corresponding to (111), (200), (220), (311) planes at 2θ theta deg 38.3°, 40.8°, 64.5°, and 74.2°. The scanning electron microscopy reported the plate like round shaped morphology of the AgNPs. The zeta potential was examined to be -17.5 mV and a size distribution by intensity of 157.6 d. nm was observed. The EDX was employed to determine the purity of samples by reporting a strong peak of silver (Ag). The degradation activity was examined by photocatalytic removal of methylene blue and malachite green dyes from textile wastewater. The textile wastewater showed a decrease of methylene blue by 25% and 58.3%. The malachite green was also reduced by 33.3% and 60%, which was remarkably significant owing to the presence of the complex factor in the natural environment. The study sets a promising record to harbor the full potential of available food waste resource, such as spent black tea to form SBT-AgNPs and its application in the dye removal from textile waste. The multifaceted outcomes of this study resulted in an eco-friendly procedure, thereby reusing the waste material for environmental cleanup.

The use of bacteria in the synthesis of silver nanoparticles (AgNPs) emerges as an ecofriendly and exciting approach. In the present study, we reported the biosynthesis of AgNPs by using culture supernatant of the bacteria Bacillus licheniformis (MN900686). The biogenically synthesized AgNPs were confirmed by the change in the color of the culture filtrate from yellow to brown after the addition of AgNO3. Further characterization performed by means of UV vis-spectroscopy showed absorption peak at 414 nm which confirmed the formation of AgNPs. Fourier Transfer infrared (FTIR) confirmed the involvement of biological molecules in the formation of nanoparticles (NPs). The SEM revealed that the NPs have approximately 38 nm size. The agar well diffusion assay was used to determine antibacterial activity while tube dilution method was used to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The human pathogenic bacterial strains i.e., P. aeruginosa (MN900691) and B. subtilis (MN900684), were used as test strains. The anti-bacterial assay against test strains revealed that these NPs showed concentration dependent increased zone of inhibition (ZOI). The maximum ZOI at 25 µL of AgNPs was 20 mm against B. subtilis after 24 hours of incubation. One-way ANOVA test showed significant ZOI (p ≤ 0.05) against B. subtilis. The MIC was ranged from 4.3-6.6 μg/mL while MBC ranged from 8.3 to 6.6 μg/mL. Overall, this study suggested that the biogenically synthesized NPs are an effective alternative source of antimicrobials against pathogenic bacteria.

Feather wastes-byproduct of commercial poultry processing plant is produced in large amounts. Keratinolytic enzymes produced by feather degrading bacteria can easily degrade these waste products releasing pure keratin as a residue. The aim of present study was to isolate, and characterize feather degrading bacteria as well as assess the keratinolytic potential of purified enzyme. Three feather degrading bacteria (dps3, wps1 and dcs1) were isolated from feathers of domestic chickens. Preliminary characterization of isolated bacteria revealed these isolates belonging to genus Bacillus. 16S rRNA gene sequencing identified the isolates as B. subtilis dps3 (MW255302), B. cereus wps1 (MW255303) and B. licheniformis dcs1 (MW255304). Cell free supernatant of B. licheniformis dcs1 degraded feathers completely in 14 days indicating its keratinolytic ability. Purification of keratinase enzyme from B. licheniformis dcs1 was performed using column chromatography. SDS-PAGE indicated its molecular weight as 32 KDa. Kerotinolytice activity was maximum at optimum pH of 7 and 45°C temperature. Enzyme showed the potential to degrade keratin material such as hairs and nails of humans. Findings of current study suggested that purified enzyme possess potential to upgrade nutritional quality of poultry waste containing keratin and might play as important biotechnological tool for keratin hydrolysis.

Graphical SCFAs exert dual roles in health and disease by modulating immune responses, inflammation, and fibrosis across organs, influencing salutogenesis and pathogenesis through dose, cell-specific, and contextual factors.