Bioconversion Of Agricultural Wastes Research Articles

Protaetia brevitarsis larvae produce frass that can be used as an additive to immobilize Cd and improve fertility in alkaline soils

Bioconversion of agricultural waste by Protaetia brevitarsis larvae (PBL) holds significant promise for producing high-quality frass organic amendments. However, the effects and mechanisms of PBL frass on Cd immobilization in an alkaline environment remain poorly understood. In this study, three types of frass, namely maize straw frass (MF), rice straw frass (RF), and sawdust frass (SF), were produced by feeding PBL. The Cd immobilization efficiencies of three frass in alkaline solutions and soils were investigated through batch sorption and incubation experiments, and spectroscopic techniques were employed to elucidate the sorption mechanisms of Cd onto different frass at the molecular level. The results showed that MF proved to be an efficient sorbent for Cd in alkaline solutions (176.67–227.27 mg g−1). X-ray absorption near-edge structure (XANES) spectroscopy indicated that Cd immobilization in frass is primarily attributed to the association with organic matter (OM-Cd, 78–90%). And MF had more oxygen-containing functional groups than the other frass. In weakly alkaline soils, MF application (0.5–1.5%) significantly decreased Cd bioavailability (5.65–18.48%) and concurrently improved soil nutrients (2.21–56.79%). Redundancy analysis (RDA) unveiled that pH, CEC, and available P were important factors controlling Cd fractions. Path analysis demonstrated that MF application affected Cd bioavailability directly and indirectly by influencing soil chemical properties and nutrients. In summary, MF, the product of PBL-mediated conversion maize straw, demonstrated promise as an effective organic amendment for Cd immobilization and fertility improvement in alkaline soils.

345 Bioconversion Treatment of Corn Stover Can Create Cheap Feed Resource for Limited Resource Farmers

Abstract The study aimed to improve the nutritive value of corn stover to provide a viable and sustainable source of cheap feed resource for ruminant production since feed is the single largest cost in any livestock enterprise. Corn stover is the largest non-food biomass available in the United States. It could be a low-cost feed, but high lignocellulose content limits both digestibility and nutritive value. Some fungi, especially white rot fungi (WRF), are known to selectively degrade fiber lignin and secrete bioactive compounds that could benefit digestibility and feed value. Pleurotus ostreatus is a mushroom-forming WRF. We tested corn stover fermented with P. ostreatus for improvement in nutrients and digestibility (Table 1). Two ruminally cannulated dairy cows were used in an in vitro study to test the effect of P. ostreatus use in solid state fermentation on the chemical composition in corn stover. The experiment was 2 x 3 factorial design with 4 replicates sampled at 6, 24 and 48 h on treated and untreated (control) corn stover. The dry matter disappearance (DMd) and volatile fatty acid (VFA) production (Table 2). Treatments were 1) untreated corn stover as control, and 2) corn stover treated with P. ostreatus. Crude protein (CP) and ash were significantly (P < 0.001) impacted with 52.9 and 31.2% increment in CP and ash respectively for treated samples. We noted an increase (P < 0.001) of 106 to 681% in microbial yield in treated vs untreated samples which demonstrated a greater potential for increased microbial protein synthesis. Acid detergent fiber, neutral detergent fiber and hemicellulose were significantly reduced (P < 0.001) by 6.71, 18.2 and 37.8%, respectively for the treated samples. Non-fiber carbohydrate was significantly (P < 0.001) impacted with a 118% increment and both DMd and total VFA were significantly (P < 0.001) greater, ranging between 40.9 to 240% and 5.85 to 11.2%, respectively (Table 3). Additionally, the rumen fermentation pathway favored the production of propionate with a significant (P < 0.001) treatment and time effect that resulted in 9.37 - 14.0% increment in propionate production for the treated samples. Consequently, a significant (P < 0.001) effect was observed in acetate production with 1.76 - 4.01% reduction, which resulted in 7.09 - 11.42% reduction in A:P ratio for the treated samples (Table 4). The study showed that bioconversion can improve the feeding value of corn stover to provide an economical novel feed resource, and that corn stover spent mushroom substrate could potentially substitute conventional feeds to support animal requirements. Although actual cow performance remains to be determined experimentally via feeding studies, we are convinced that bioconversion of agricultural waste from crop farming could be a functional system approach to alleviate the feed cost challenges faced by socially disadvantaged and limited-resource farmers.

Bioconversion of Agricultural Wastes into a Value-Added Product: Straw of Norwegian Grains Composted with Dairy Manure Food Waste Digestate in Mushroom Cultivation

Commercial mushroom production is based on composted locally available agro-industrial wastes rich in carbon and nitrogen such as wheat straw supplemented with chicken manure. Either component can be replaced by other kinds of grain straw: barley, oat, or a mixture of different straw types and combined with diary manure—food waste digestate after anaerobic biogas digestion. Original, unseparated liquid digestate is nutritious, rich in nitrogen and organic matter. This research aimed to investigate the effect of digestate and different straw ratios on the composting process and productivity and their consequent effect on mushroom cultivation parameters of Agaricus subrufescens. All investigated experimental mushroom compost (EMC) types worked well during the composting process, reaching the desired moisture of 65–75%, N content of 1.43–1.93%, and a C/N ratio ranging from 21.5 to 29.1, supporting growth of mycelium and producing mushrooms. Supplementation with barley straw resulted in better EMC structure with the highest yield and biological efficiency (BE) (157.9 g kg−1; 64%), whereas oat addition gave the lowest yield and BE (88.6 g kg−1 and 38%). Precociousness (yield at mid-cycle of the crop development) was higher for oat substrates (68.9%), while earliness (days to harvest from casing) was lower for barley EMC.

Lignocellulolytic activity of Pleurotus ostreatus under solid state fermentation using silage, stover, and cobs of maize

Lignocellulolytic white-rot fungi allow the bioconversion of agricultural wastes into value-added products that are used in a myriad of applications. The aim of this work was to use corn residues (Zea mays L.) to produce valuable products under solid-state fermentation (SSF) with Pleurotus ostreatus. White-rot fungus P. ostreatus was isolated from maize silage (MS) and thereafter it was inoculated on MS as substrate and compared with maize stover (MSt) and maize cobs (MC) to determine the best lignocellulosic substrate for the production of lignocellulolytic enzymes and extracellular protein. The MS gave the highest productivity of CMCase (368.2 U/mL), FPase (170.5 U/mL), laccase (11.4 U/mL), and MnPase (6.6 U/mL). This is compared to productivity on MSt of 222 U/mL, 50.2 U/mL, 4.55 U/mL, and 2.57 U/mL, respectively; and productivity on MC at the same incubation period as 150.5 U/mL, 48.2 U/mL, 3.58 U/mL, and 2.5 U/mL, respectively. The levels of enzyme production declined with increasing incubation period after 15 and 20 days using MS and MC, respectively, as substrates. Maximum liberated extracellular protein content (754 to 878 µg/mL) was recorded using MS, while a low amount (343 to 408 µg/mL) was liberated with using MSt and MC.

Bioconversion of Agricultural Wastes to Polyhydroxybutyrate by Azotobacter vinelandii

Bioconversion of Agricultural Wastes to Polyhydroxybutyrate by Azotobacter vinelandii

Bioconversion of agricultural waste into poly-γ-glutamic acid in solid-state bioreactors at different scales

With the purpose of developing a novel approach of agricultural waste treatment and overcoming bottlenecks for upscaling solid-state fermentation processes, the type of aerated, continuously stirred solid-state bioreactors were used for the production of γ-PGA by Bacillus amyloliquefaciens JX-6. Using corn stalk and soybean meal, the most common agricultural waste in China, as solid substrates, the maximum production of γ-PGA was 116.88 ± 5.05 g/kg and 102.48 ± 3.30 g/kg in 50 L and 150 L bioreactors, respectively. Production of γ-PGA in 50 L bioreactor was higher than in 150 L bioreactor, demonstrating that a reduction in γ-PGA production occurred as the fermentation system enlarged. An analysis of the interactions among fermentation parameters (temperature, moisture, and pH), γ-PGA production, solid substrates and bacterial communities indicated that different bioreactor capacities caused changes in fermentation parameters and bacterial communities, which in turn affected substrate utilization and γ-PGA production. Overall, obtaining considerable amounts of γ-PGA under non-sterilized fermentation expressed that JX-6 has excellent abilities to adapt to these substrates and conditions. Bioconversion of agricultural waste into γ-PGA in scale-up fermentation was successfully conducted by creating a more stable and suitable fermentation environment in bioreactors.

Paenibacillus polymyxa bioactive compounds for agricultural and biotechnological applications

Paenibacillus polymyxa is categorized as an endospore-forming bacterium and Gram-positive bacteria, which have innate beneficial properties in modern biotechnology application. P. polymyxa extensively reviewed as plant growth promoting bacteria which directly gave benefit to the plants by improving nitrogen fixation from atmosphere, increase phosphorus solubilization and iron acquisition in soil and phytohormone production. This could reduce reliance on chemical fertilizers, which is now a source of environmental conflict and appear to be harmful to human. Therefore, application of P. polymyxa focusing only as functional microbial species in production of biofertilizers. P. polymyxa have been gaining momentum over the last couple of years. The recent discovery in microbial industrial of this bacterium is the production of bioactive compounds like exopolysaccharides (EPS). EPS is not only established as biofilm for the colonization of microbes and act as a sink for the nutrients on plant roots in the rhizosphere. Hence, EPS from P. polymyxa is also useful for health care industries such as disease diagnosis and drug manufacturing. Synthesis of hydrolytic enzymes reported as bioconversion of agricultural wastes that helps to tackle serious environmental problems by creating wealth from waste which can also acts as productive biocontrol agents against pathogens. Hence, P. polymyxa having a wide range of antibacterial metabolites and antifungal compounds, inform of volatile organic compouds, peptides and hydrolytic enzymes, This compounds and biomaterials could be commercially marketed as reliable plant biocontrol agents and pharmaceutical application. Nowadays, researcher extensively reviewed and focused their attention on the potential benefits of P. polymyxa with multiple biological functions that cannot be ignored for human health and wellness.

Bioconversion of Agricultural Wastes into High Value Biocompost: A Route to Livelihood Generation for Farmers

Agricultural farm-wastes produced after harvest of every crop are of great concern because of the problems of environmental pollution, rural sanitation, recycling and utilization. We have standardized a process of bioconversion of agricultural farm wastes at the farmer's own fields into biocompost for field application and further value-addition of bio-compost thus produced with the help of microbes of defined functional traits like biocontrol agents, plant growth promoters, phosphate solubilizers and nutrient mobilizers. After standardization of the whole process, the same was demonstrated to 456 farmers in different villages of Eastern Uttar Pradesh, India. Various farmer groups have adopted the process of bioconversion to produce biocompost and value-added bio-farm-inputs and commercialized the products for gaining economic livelihood.

Biological pretreatment and bioconversion of agricultural wastes, using ligninolytic and cellulolytic fungal consortia

ABSTRACTAgricultural wastes have attractive potential as alternate energy sources. However, a major bottleneck is to identify eco-friendly treatment methodologies to utilize them. The large diversity of unexplored, novel, and potential microorganisms hold great promise and require periodic isolation and characterization of microorganisms for bioprospection. In this study, approximately 100 fungal isolates were tested for their lignocellulolytic enzyme activities, based on plate assay, followed by quantification of enzyme activity. From this, M2E (Inonotus tropicalis) and 2a (Cerrena unicolor) showed good growth and proficient ligninolytic activity; isolates GK1 (Chaetomium globosum) and GK2 (Chaetomium brasiliense) exhibited exceptional cellulolytic activity on lignocellulosic substrates such as rice straw and sugarcane bagasse. Consortia of the potential ligninolytic and cellulolytic isolates were set up to determine their ability to biodegrade the lignocellulosic substrates such as rice straw and sugarcane bagasse. The efficiency of the consortia was determined on the basis of the increase in enzyme activity; it was also evident through scanning electron microscopy, x-ray diffraction analysis of the degraded substrates, and the sugar yield. Experiments were also carried out to compare the biological with the physical pretreatment methods. The consortium of ligninolytic and cellulolytic marine-derived fungi developed in this study prove to have the potential for application in the effective utilization of agricultural wastes.

Antiviral activity of Basidiomycete mycelia against influenza type A (serotype H1N1) and herpes simplex virus type 2 in cell culture.

In this study, we investigated the in vitro antiviral activity of the mycelia of higher mushrooms against influenza virus type A (serotype H1N1) and herpes simplex virus type 2 (HSV-2), strain BH. All 10 investigated mushroom species inhibited the reproduction of influenza virus strain A/FM/1/47 (H1N1) in MDCK cells reducing the infectious titer by 2.0-6.0 lg ID50. Four species, Pleurotus ostreatus, Fomes fomentarius, Auriporia aurea, and Trametes versicolor, were also determined to be effective against HSV-2 strain BH in RK-13 cells, with similar levels of inhibition as for influenza. For some of the investigated mushroom species-Pleurotus eryngii, Lyophyllum shimeji, and Flammulina velutipes-this is the first report of an anti-influenza effect. This study also reports the first data on the medicinal properties of A. aurea, including anti-influenza and antiherpetic activities. T. versicolor 353 mycelium was found to have a high therapeutic index (324.67), and may be a promising material for the pharmaceutical industry as an anti-influenza and antiherpetic agent with low toxicity. Mycelia with antiviral activity were obtained in our investigation by bioconversion of agricultural wastes (amaranth flour after CO2 extraction), which would reduce the cost of the final product and solve some ecological problems.

Purification and characterisation of a cellulase obtained from cocoa (Theobroma cacao) pod-degrading Bacillus coagulans Co4

Objective: Some properties of cellulase purified from the culture supernatant of Bacillus coagulans Co4, isolated from cocoa pod dumpsite were investigated for possible biotechnological applications. Methods: The crude cellulase was purified to apparent homogeneity using a combination of acetone precipitation, CM Sepharose CL-6B ion exchange chromatography and gel filtration on Sephadex G-100. The molecular and thermodynamic properties of the purified enzyme were studied following standard procedures. Results: The specific activity of the purified cellulase rose from 0.10 to 47 units/mg of protein, at the end of purification. The molecular weight was found to be 14.5 kDa; and an apparent K m value of 0.18±0.06 mg/ml of carboxylmethylcellulose. The optimum pH and temperature were 7.5 and 60 o C respectively. The activation energy for carboxylmethylcellulose hydrolysis (E a ) was 16.5 kJ/mol. Na+ and K+ had no effects on its activity at concentrations up to 200 mM, whereas Ca 2+ and Mg 2+ served as inhibitors at concentrations above 25 and 40 mM respectively. The cellulase retained 40% residual activity when heated at 60oC for 40 minutes. Conclusison: On the basis of these properties, it is concluded that the purified cellulase is moderately thermostable and may have applications in the bioconversion of agricultural wastes into economically useful products.

Biotechnological applications and potential of wood-degrading mushrooms of the genus Pleurotus.

The genus Pleurotus comprises a group of edible ligninolytic mushrooms with medicinal properties and important biotechnological and environmental applications. The cultivation of Pleurotus spp is an economically important food industry worldwide which has expanded in the past few years. P. ostreatus is the third most important cultivated mushroom for food purposes. Nutritionally, it has unique flavor and aromatic properties; and it is considered to be rich in protein, fiber, carbohydrates, vitamins and minerals. Pleurotus spp are promising as medicinal mushrooms, exhibiting hematological, antiviral, antitumor, antibiotic, antibacterial, hypocholesterolic and immunomodulation activities. The bioactive molecules isolated from the different fungi are polysaccharides. One of the most important aspects of Pleurotus spp is related to the use of their ligninolytic system for a variety of applications, such as the bioconversion of agricultural wastes into valuable products for animal feed and other food products and the use of their ligninolytic enzymes for the biodegradation of organopollutants, xenobiotics and industrial contaminants. In this Mini-Review, we describe the properties of Pleurotus spp in relation to their biotechnological applications and potential.