Sludge granulation and efficiency of phase separator in UASB reactor treating combined industrial effluent

Sludge granulation and the effect of gas-liquid-solid separator （GLSS） design on the efficiency of upflow anaerobic sludge blanket （UASB） and upflow anaerobic sludge filter （UASF） reactors, operating at HRTs ranging from 3 to 12 h was investigated. VSS/TS ratio gradually increased in both the reactors with increasing sludge age （from 0.5 to more than 0.7 for UASB reactor and 0.012 to 0.043 for UASF reactor）. X-Ray diffraction analysis of the UASF sludge showed the presence of expanding clays revealing its additional absorption capability. Fuoraphyllite and albite precipitation related to excellular polymers of the microbial shell structure, showed the extended growth of microorganisms during sludge granulation. A gradual decrease （82%-69%） in COD removal with decreasing HRT was apparent in UASF reactor. In case of UASB reactor, this decrease was marginal because addition of GLSS device significantly improved （14%-20%） the overall efficiency of the UASB reactor. GLSS enhanced the efficiency of the UASB reactor by increasing the settleability of suspended particles and accelerating the coagulation of colloidal particles due to the velocity gradient.

Phytoremediation Strategies for Heavy Metal Contamination: A Review on Sustainable Approach for Environmental Restoration

Current globalization trends and important breakthroughs globally need a complete study of heavy metal contamination, its causes, its impacts on human and environmental health, and different remediation strategies. Heavy metal pollution is mostly produced by urbanization and industry, which threatens ecosystems and human health. Herein, we discuss a sustainable environmental restoration strategy employing phytoremediation for heavy metal pollution, the carcinogenic, mutagenic, and cytotoxic effects of heavy metals such as cadmium, copper, mercury, selenium, zinc, arsenic, chromium, lead, nickel, and silver, which may be fatal. Phytoremediation, which was prioritized, uses plants to remove, accumulate, and depollute pollutants. This eco-friendly method may safely collect, accumulate, and detoxify toxins using plants, making it popular. This study covers phytostabilization, phytodegradation, rhizodegradation, phytoextraction, phytovolatilization, and rhizofiltration. A phytoremediation process’s efficiency in varied environmental circumstances depends on these components’ complex interplay. This paper also introduces developing phytoremediation approaches including microbe-assisted, chemical-assisted, and organic or bio-char use. These advancements attempt to overcome conventional phytoremediation’s limitations, such as limited suitable plant species, location problems, and sluggish remediation. Current research includes machine learning techniques and computer modeling, biostimulation, genetic engineering, bioaugmentation, and hybrid remediation. These front-line solutions show that phytoremediation research is developing towards transdisciplinary efficiency enhancement. We acknowledge phytoremediation’s promise but also its drawbacks, such as site-specific variables, biomass buildup, and sluggish remediation, as well as ongoing research to address them. In conclusion, heavy metal pollution threatens the ecology and public health and must be reduced. Phytoremediation treats heavy metal pollution in different ways. Over time, phytoremediation systems have developed unique ways that improve efficiency. Despite difficulties like site-specificity, sluggish remediation, and biomass buildup potential, phytoremediation is still a vital tool for environmental sustainability.

Decolorization of Blue CL-BR dye by AOPs using bleach wastewater as source of H_2O_2

This research was focused on the investigation of the efficacy of advanced oxidation processes （Fenton, ozonation and UV/H2O2） for decolorization of reactive azo dye （Blue CL-BR） using bleach wastewater as possible source of H2O2. All the experiments were performed on the laboratory scale set-up. The results showed that colour removal efficiencies by UV or bleach （H2O2） alone were not so efficient. Fenton process with bleach wastewater was found to be the most effective at process conditions such as pH of 3 and HEO2/Fe^2＋ ratio of 24：1, resulting in 64% colour removal. Almost complete colour removal, i.e., 99% and 95% were achieved by UV//H2O2 and UV/bleach wastewater in 30 and 60 min, respectively. Ozonation proved an efficient method for decolorization of Blue CL-BR dye at alkaline pH. It was possible to achieve 98% colour removal with 30 min of ozonation at pH 9. The colour removal of dye was found to follow first order kinetics.

Evaluation of extraction protocols for anti-diabetic phytochemical substances from medicinal plants

AIM To examine the efficacy of three extraction techniques: Soxhlet-extraction(SE), cold-maceration(CM) and microwave-assisted-extraction(MAE) using 80% methanol as solvent. METHODS The study was performed on each of 50 g of Vernonia amygdalina(VA) and Occimum gratissimum(OG) leaves respectively. The percentage yield, duration of extraction, volume of solvent used, qualitative and quantitative phytoconstituents present was compared. The biological activities(hypoglycemic effect) were investigated using albino wistar rat model of diabetes mellitus(n = 36) with a combined dose(1:1) of the two plants leaf extracts(250 mg/kg b.w.) from the three methods. Theextracts were administered orally, once daily for 21 d.RESULTS In this report, the percentage VA extract yield from MAE was highest(20.9% ± 1.05%) within 39 min using 250 m L of solvent, when compared to the CM(14.35% ± 0.28%) within 4320 min using 900 m L of solvent and SE(15.75% ± 0.71%) within 265 min using 500 m L of solvent. The percentage differences in OG extract yield between: MAE vs SE was 41.05%; MAE vs CM was 46.81% and SE vs CM was 9.77%. The qualitative chemical analysis of the two plants showed no difference in the various phytoconstituents tested, but differs quantitatively in the amount of the individual phytoconstituents, as MAE had significantly high yield(P > 0.05) on phenolics, saponins and tannins. SE technique gave significantly high yield(P > 0.05) on alkaloid, while CM gave significant high yield on flavonoids. The extracts from CM exhibited a significantly(P > 0.05) better hypoglycemic activity within the first 14-d of treatment(43.3% ± 3.62%) when compared to MAE(36.5% ± 0.08%) and SE methods(33.3% ± 1.60%). However, the percentage hypoglycemic activity, 21 d post-treatment with 250 mg/kg b.w. extract from MAE was 72.6% ± 1.03% and it was more comparable to 10 mg/kg b.w. glibenclamide treated group(75.0% ± 0.73%), unlike the SE(69.5% ± 0.71%) and CM(69.1% ± 1.03%). CONCLUSION CM technique produces extract with better hypoglycemic activity, whereas; MAE is a better option for high yield of phytoconstituents using less solvent within a short time.

HIV-Associated Polyneuropathy in Resource-Limited Settings: Genetic Predisposition and Vitamin Variations

Human immunodeficiency virus-related polyneuropathy remains a painful condition resulting from damaged nerve endings. HIV infection strongly associates with a predominantly polyneuropathy that is attributed to HIV infection itself, or a toxic neuropathy associated with combination antiretroviral therapy (CART). In non-HIV-infected individuals, both deficiency and high intake of vitamins have been associated with polyneuropathy. For that reason, clinicians recommend vitamin supplements before and during CART. Although some, but not all, HIV-related vitamin deficiencies may replete during treatment with CART, it is predictable that high vitamin supplement intakes may contribute to nerve disorders. In resource-limited settings where the diagnosis of polyneuropathy heavily relies on symptoms, data on risk factors for polyneuropathy including vitamin status, alcohol consumption, and co-infections are limited. In addition, studies on genetic influence on the concentration of micronutrients in the blood of long-term users of CART are scarce. Possible sources of high intakes of vitamins could arise from the fact that a number of HIV-infected persons self-medicate. In addition, since HIV-infected individuals have an increased lifespan, relying on symptoms alone to specifically diagnose HIV-associated neuropathies could be a barrier to effective treatment in recourse-poor settings. This paper reviews evidence on single nucleotide polymorphisms (SNPs) with the potential to influence bioavailability of vitamins in HIV-infected patients. Genome-wide association studies have reported SNPs in alkaline phosphatase, fucosyltransferase 2, cubilin, transcobalamin 1, and tumor necrosis factor as potential determinants of various blood levels of vitamin B-6, B-12 and E. As long term CART increasingly become, personalized, future research should focus on SNPs, which influence vitamin blood levels, and with potential to augment long-term treatment with CART.