Innovative production of value-added products using agro-industrial wastes via solid-state fermentation.

The prevalence of organic solid waste worldwide has turned into a problem that requires comprehensive treatment on all fronts. The amount of agricultural waste generated by agro-based industries has more than triplet. It not only pollutes the environment but also wastes a lot of beneficial biomass resources. These wastes may be utilized as a different option/source for the manufacturing of many goods, including biogas, biofertilizers, biofuel, mushrooms and tempeh as the primary ingredients in numerous industries. Utilizing agro-industrial wastes as good raw materials may provide cost reduction and lower environmental pollution levels. Agro-industrial wastes are converted into biofuels, enzymes, vitamin supplements, antioxidants, livestock feed, antibiotics, biofertilizers and other compounds via solid-state fermentation (SSF). By definition, SSF is a method used when there is little to no free water available. As a result, it permits the use of solid materials as biotransformation substrates. Through SSF methods, a variety of microorganisms are employed to produce these worthwhile things. SSFs are therefore reviewed and discussed along with their impact on the production of value-added items. This review will provide thorough essential details information on recycling and the use of agricultural waste.

Development of novel kinetic model based on microbiome and biochar for in-situ remediation of total petroleum hydrocarbons (TPHs) contaminated soil.

A novel kinetic model has been developed to explain the degradation of total petroleum hydrocarbons. Microbiome engineered biochar amendment may result in a synergistic impact on degradation of total petroleum hydrocarbons (TPHs). Therefore, the present study analyzed the potential of hydrocarbon-degrading bacteria A designated as Aeromonas hydrophila YL17 and B as Shewanella putrefaciens Pdp11 morphological characterized as rod shaped, anaerobic and gram-negative immobilized on biochar, and the degradation efficiency was measured by gravimetric analysis and gas chromatography-mass spectrometry (GC-MS). Whole genome sequencing of both strains revealed the existence of genes responsible for hydrocarbon degradation. In 60 days remediation setup, the treatment consisting of immobilization of both strains on biochar proved more efficient with less half-life and better biodegradation potentials compared to biochar without strains for decreasing the content of TPHs and n-alkanes (C12-C18). Enzymatic content and microbiological respiration showed that biochar acted as a soil fertilizer and carbon reservoir and enhanced microbial activities. The removal efficiency of hydrocarbons was found to be a maximum of 67% in soil samples treated with biochar immobilized with both strains (A + B), followed by biochar immobilized with strain B 34%, biochar immobilized with strain A 29% and with biochar 24%, respectively. A 39%, 36%, and 41% increase was observed in fluorescein diacetate (FDA) hydrolysis, polyphenol oxidase and dehydrogenase activities in immobilized biochar with both strains as compared to control and individual treatment of biochar and strains. An increase of 35% was observed in the respiration rate with the immobilization of both strains on biochar. While a maximum colony forming unit (CFU/g) was found 9.25 with immobilization of both strains on biochar at 40 days of remediation. The degradation efficiency was due to synergistic effect of both biochar and bacteria based amendment on the soil enzymatic activity and microbial respiration.

Treatment technologies for olive mill wastewater with impacts on plants.

Olive mill wastewater (OMW), produced during olive oil production, contains high levels of salt contents, organic matter, suspended particles, and toxic chemicals (particularly phenols), which all result in increased biological and chemical oxygen demand. Olive Oil Mills' Wastes (OMW), which have dark brown color with unpleasant smell, consist mainly of water, high organic (mainly phenols and polyphenols) and low inorganic compounds (e.g. potassium and phosphorus), as well as grease. OMW components can negatively affect soil's physical, chemical, and biological properties, rendering it phytotoxic. However, OMW can positively affect plants' development when it's applied to the soil after pretreatment and treatment processes due to its high mineral contents and organic matter. There are various approaches for removing impurities and the treatment of OMW including chemical, biological, thermal, physiochemical, and biophysical processes. Physical techniques involve filtration, dilution, and centrifugation. Thermal methods include combustion and pyrolysis; biological techniques use anaerobic and aerobic techniques, whereas adsorption and electrocoagulation act as physiochemical methods, and coagulation and flocculation as biophysical methods. In contrast, combined biological treatment methods use co-digestion and composting. A comparison of the effects of both treated and untreated OMW samples on plant development and soil parameters can help us to understand the potential role of OMW in increasing soil fertility. This review discusses the impacts of untreated OMW and treated OMW in terms of soil characteristics, seed germination, and plant growth. This review summarizes all alternative approaches and technologies for pretreatment, treatment, and recovery of valuable byproducts and reuse of OMW across the world.

Advances in Biochar and PGPR engineering system for hydrocarbon degradation: A promising strategy for environmental remediation.

In soil, polycyclic aromatic hydrocarbons (PAHs) have resulted in severe environmental deterioration, compromised soil characteristics, and negatively affect all life forms, including humans. Developing appropriate and effective clean-up technology is crucial in solving the contamination issues. The traditional methods to treat PHAs contaminated soil are less effective and not ecofriendly. Bioremediation, based on bioaugmentation and biostimulation approaches, is a promising strategy for remediating contaminated soil. The use of plant growth-promoting rhizobacteria (PGPR) as a bioaugmentation tool is an effective technique for treating hydrocarbon contaminated soil. Plant growth-promoting rhizobacteria (PGPR) are group of rhizospheric bacteria that colonize the roots of plants. Biochar is a carbon-rich residue, which acts as a source of nutrients, and is also a bio-stimulating candidate to enhance the activities of oil-degrading bacteria. The application of biochar as a nutrient source to bioremediate oil-contaminated soil is a promising approach for reducing PHA contamination. Biochar induces polyaromatic hydrocarbons (PAHs) immobilization and removes the contaminants by various methods such as ion exchange electrostatic attractions and volatilization. In comparison, PGPR produce multiple types of biosurfactants to enhance the adsorption of hydrocarbons and mineralize the hydrocarbons with the conversion to less toxic substances. During the last few decades, the use of PGPR and biochar in the bioremediation of hydrocarbons-contaminated soil has gained greater importance. Therefore, developing and applying a PGPR-biochar-based remediating system can help manage hazardous PAH contaminated soil. The goal of this review paper is to (i) provide an overview of the PGPR mechanism for degradation of hydrocarbons and (ii) discuss the contaminants absorbent by biochar and its characteristics (iii) critically discuss the combined effect of PGPR and biochar for degradation of hydrocarbons by decreasing their mobility and bioavailability. The present review focuses on techniques of bioaugmentation and biostimulation based on use of PGPR and biochar in remediating the oil-contaminated soil.

Designing of pretreatment filter technique for reduction of phenolic constituents from olive-mill wastewater and testing its impact on wheat germination.

Olive oil extraction produces a great volume of olive mill wastewater (OMW), which is considered a serious ecological challenge. In this study, we have designed and tested a trickling filter consisting of seven different layers of natural material, including (coarse gravel, fine gravel, lime (Ca (OH)2), sand (SiO2), carbon char, sponge/mesh), to treat OMW. The filter process involved physical separation, filtration, coagulation and adsorption with the removal of COD (69.8%), BOD (40.2%), Phenolic contents (90%), pH (41%), EC (41.6%) and total suspended solids (TSS) (69%). Our results have shown that treated OMW has a high potential oxidant activity. T7, Untreated OMW at 1:6 dilutions, had the strongest correlation (i.e. 0.97), while untreated OMW had the lowest IC50 (7.62 g ml-1), which shown the best DPPH radical scavenging capabilities. While pure Untreated OMW has the maximum radical scavenging activity, 63%, treated (1:6) diluted OMW exhibits the lowest value i. e 9% when phosphomolybdate assay was done. HPLC analysis showed that the trickling filter removed the vanillic acid, caffeic acid and reduced the contents of phenolic components such as gallic acid, hydroxytyrosol, vanillin, quercetin and catechol. Filtered OMW was also tested for its germination efficacy at various dilutions (1:0, 1:2, 1:4, 1:6). A remarkable improvement in germination percentage, germination index, seedling length, seedling vigor index, promptness index, stress tolerance index (76.7%, 68.4%, 51.7%, 82.1%, 54.8%, and 66.7%, respectively) has shown the efficiency of treated OMW at 1:6 dilutions. The results from this study show the efficiency of our filter design which can be further used.

Biotransformation of dimethoate into novel metabolites by bacterial isolate Pseudomonas kilonensis MB490.

Bacterial strain (Pseudomonas kilonensis MB490) isolated from agricultural fields of Mianwali, was selected to check its potential to degrade Organophosphate insecticide dimethoate (DM). Strain MB490 was able to degrade dimethoate equally well at given pH range (6.0, 7.0 and 8.0), thus showing its pH independence for dimethoate degradation. Optimum temperature for dimethoate degradation varied from 25-30 °C. There was more dimethoate degradation under shaking conditions with optimum growth. Strain MB490 showed 90% dimethoate degradation in M-9 broth and 90.6% in soil slurry, while exhibited 81.5% dimethoate degradation in soil microcosm within 9 days, based on HPLC analysis of bacterial samples supplemented with 200 mg/L dimethoate. The average half-life (t 1/2) of dimethoate after bacterial degradation ranged from 1.95 days in 1st phase to 5 days in 2nd phase in M-9 broth, soil slurry and soil microcosm, while in control media without bacteria, it ranged from 30 to 64.3 days. GCMS investigation revealed the transformation of dimethoate into 5 metabolic products namely Methyl diethanol amine, Aspartylglycine ethyl ester, Phosphonothioic acid propyl-O, S-dimethyl ester, O, O, O-Trimethyl thiophosphate and omethoate which were ultimately mineralized by the strain MB490, providing energy for its growth.

Mini-Review- A mini-review of therapeutic potential of Mangifera indica L.

Among known species of 69 Mangifera, Mangifera indica L. is a medicinal plant being used in tropical regions by indigenous people. It has been a main plant species being used in Ayurvedic as well as indigenous medical systems form 4000 years. Components of M. indica are recurrently used as a traditional medicine system to cure numerous ailments. Active constituents are present in stem bark, leaves, heartwood, roots and fruit and have antioxidant, anti-inflammatory, radioprotective, antitumor, immune-modulatory, anti-allergic, anti-diabetic, anti-bone resorption, mono-amine oxidase inhibiting, anti-viral, anti-fungal, anti-bacterial, anti-spasmodic, antidiarrheal, anti-malarial, antiparasitic as well as lipolytic properties. In spite of essential progress in phyto-chemical and medicinal analysis of M. indica, more efforts are needed to explore M. indica active components and their application in pharmaceutical industry. In this review, we focus on recent information about chemical constituents and pharmacological uses of M. indica.