Ionic liquid-assisted pretreatment of lignocellulosic biomass using purified Streptomyces MS2A cellulase for bioethanol production.

In recent years, the process of producing bioethanol from lignocellulosic biomass through biorefining has become increasingly important. However, to obtain a high yield of ethanol, the complex structures in the feedstock must be broken down into simple sugars. A cost-effective and innovative method for achieving this is ionic liquid pre-treatment, which is widely used to efficiently hydrolyze the lignocellulosic material. The study aims to produce a significant profusion of bioethanol via catalytic hydrolysis of ionic liquid-treated lignocellulose biomass. The current study reports the purification of Streptomyces sp. MS2A cellulase via ultrafiltration and gel permeation chromatography. The kinetic parameters and the biochemical nature of the purified cellulase were analyzed for the effective breakdown of the EMIM[OAC] treated lignocellulose chain. The two-step cellulase purification resulted in 6.28 and 12.44 purification folds. The purified cellulase shows a Km value of 0.82 ± 0.21 mM, and a Vmax value of 85.59 ± 8.87 µmol min-1 mg-1 with the catalytic efficiency of 1.027 S-1. The thermodynamic parameters like ΔH, ΔS, and ΔG of the system were studied along with the thermal deactivation kinetics of cellulase. The optimal temperature and pH of the purified cellulase enzyme for hydrolysis was found to be 40 °C and 7. The rice husk and wheat husk used in this study were pretreated with the EMIM [OAC] ionic liquid and the change in the structure of lignocellulosic biomass was observed via HRSEM. The ionic liquid treated biomass showed the highest catalytic hydrolysis yield of 106.66 ± 0.19 mol/ml on the third day. The obtained glucose was fermented with Saccharomyces cerevisiae to yield 23.43 g of ethanol/l of glucose from the rice husk (RH) and 24.28 g of ethanol/l of glucose from the wheat husk (WH).

Genomic analysis of lignocellulolytic enzyme producing novel Streptomyces sp.MS2A for the bioethanol applications.

The conversion of lignocellulosic waste to energy offers a cost-effective biofuel. The current study discusses the utilization of cellulose in rice husks by lichen-associated Streptomyces sp. MS2A via carbohydrate metabolism. Out of 39 actinobacteria, one actinobacterial strain MS2A, showed CMCase, FPase, and cellobiohydrolase activity. The whole genome analysis of Streptomyces sp. MS2A showed maximum similarity with Streptomyces sp. CCM_MD2014. The genome analysis confirmed the presence of cellulose-degrading genes along with xylan-degrading genes that code for GH3, GH6, GH9, GH11, GH43, GH51, and 15 other GH families with glycosyl transferase, carbohydrate-binding modules, and energy metabolism groups. Protein family analysis corroborates the enzyme family. Among the 19,402 genes of Streptomyces sp. MS2A, approximately 70 GH family codes for lignocellulose degradation enzymes. The structure of cellulase was modeled and validated. Scanning electron microscopy and gas chromatography-mass spectrometry (GCMS) was performed to analyze the lignocellulosic degradation of rice husk and the end product bioethanol.

A comprehensive review on strategic study of cellulase producing marine actinobacteria for biofuel applications.

Every year, 180 billion tonnes of cellulose are produced by plants as waste biomass after the cultivation of the desired product. One of the smart and effective ways to utilize this biomass rather than burn it is to utilize the biomass to adequately meet the energy needs with the help of microbial cellulase that can catalytically convert the cellulose into simple sugar units. Marine actinobacteria is one of the plentiful gram-positive bacteria known for its industrial application as it can produce multienzyme cellulase with high thermal tolerance, pH stability and high resistant towards metal ions and salt concentration, along with other antimicrobial properties. Highly stable cellulase obtained from marine actinobacteria will convert the cellulose biomass into glucose, which is the precursor for biofuel production. This review will provide a comprehensive outlook of various strategic applications of cellulase from marine actinobacteria which can facilitate the breakdown of lignocellulosic biomass to bioenergy with respect to its characteristics based on the location/environment that the organism was collected and its screening strategies followed by adopted methodologies to mine the novel cellulase genome and enhance the production, thereby increasing the activity of cellulase continued by effective immobilization on novel substrates for the multiple usage of cellulase along with the industrial applications.

Synthesis of recyclable GO/Cu3(BTC)2/Fe3O4 hybrid nanocomposites with enhanced photocatalytic degradation of aflatoxin B1.

This study evaluated the photocatalytic performance of the activated carbon assisted GO/Cu3(BTC)2/Fe3O4 photocatalyst for aflatoxin B1 (AFB1) degradation under ultraviolet light. The nanocomposite was characterized by Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption-desorption. The numerous factors influencing the degradation efficiency of AFB1 including catalyst dose, pH importance, and contact time were also probed. The elevated degradation performance of AFB1 by 99% was due to a larger surface area and improved GO/Cu3(BTC)2/Fe3O4 photocatalyst. The degradation process followed a pseudo-first-order kinetic model. Moreover, it is possible to quickly isolate the catalyst from the solution and retain successful operation. In the degradation of AFB1, the hole(h+) and the hydroxyl radicals(OH) were found to play a significant role. These studies showed that GO/Cu3(BTC)2/Fe3O4 has high capturing capacity and photoactivity synergy, thereby offering a quick effect, and green solution to AFB1 degradation.

Influence of 2D template-assisted (SBA-15) metal oxide Co3O4 for pseudocapacitive and dye degradation application.

Cobalt oxide (Co3O4) is a low-cost material exhibiting excellent physicochemical and photocatalytic properties indicating its potential use for next-generation eco-friendly energy storage and photocatalytic degradation applications. In this study, Co3O4 nanoarcs were synthesized using SBA-15 as a template by microwave-assisted method to form an S15/m-Co3O4 product. Characterization was done by low and wide-angle X-Ray diffraction, and Fourier transformed infra-red spectroscopic studies confirming the presence of S15/m-Co3O4. Scanning Electron Microscope images proved the agglomerated nanotube and nanoarcs like the structure of SBA-15 and S15/m- Co3O4, respectively. Electrochemical studies included cyclic voltammetry, charge/discharge, retention capacity, and electron impedance spectroscopy studies in a 3-electrode system. S15/m-Co3O4 nanoarcs, as the electrode material, was revealed to have a specific capacity of 87.5 C/g in 1 M KOH solution. Upon running 1000 cycles, the material had excellent capacity retention of 87%. The S15/m-Co3O4 product also underwent photocatalytic degradation studies. The Rhodamine R6G dye degradation by S15/m-Co3O4 under UV irradiation exhibited a high degradation percentage of 97.7%, following the first-order kinetics. S15/m-Co3O4 has proven to be biocompatible and can be used to enhance supercapacitors which are an ideal alternative to conventional batteries for energy storage applications. Thus, the data produced proves S15/m-Co3O4 nanoarcs is an excellent electrode material for pseudocapacitive application and a catalyst for photocatalytic degradation of dye molecules.

Biogenic Synthesis of Iron Oxide Nanoparticles Using Enterococcus faecalis: Adsorption of Hexavalent Chromium from Aqueous Solution and In Vitro Cytotoxicity Analysis.

The biological synthesis of nanoparticles is emerging as a potential method for nanoparticle synthesis due to its non-toxicity and simplicity. In the present study, a bacterium resistant to heavy metals was isolated from a metal-contaminated site and we aimed to report the synthesis of Fe3O4 nanoparticles via co-precipitation using bacterial exopolysaccharides (EPS) derived from Enterococcus faecalis_RMSN6 strains. A three-variable Box-Behnken design was used for determining the optimal conditions of the Fe3O4 NPs synthesis process. The synthesized Fe3O4 NPs were thoroughly characterized through multiple analytical techniques such as XRD, UV-Visible spectroscopy, FTIR spectroscopy and finally SEM analysis to understand the surface morphology. Fe3O4 NPs were then probed for the Cr(VI) ion adsorption studies. The important parameters such as optimization of initial concentration of Cr(VI) ions, effects of contact time, pH of the solution and contact time on quantity of Cr(VI) adsorbed were studied in detail. The maximum adsorption capacity of the nanoparticles was found to be 98.03 mg/g. The nanoparticles could retain up to 73% of their efficiency of chromium removal for up to 5 cycles. Additionally, prepared Fe3O4 NPs in the concentration were subjected to cytotoxicity studies using an MTT assay. The investigations using Fe3O4 NPs displayed a substantial dose-dependent effect on the A594 cells. The research elucidates that the Fe3O4 NPs synthesized from EPS of E. faecalis_RMSN6 can be used for the removal of heavy metal contaminants from wastewater.

Detection, Contamination, Toxicity, and Prevention Methods of Ochratoxins: An Update Review.

Ochratoxins (OTs) with nephrotoxic, immunosuppressive, teratogenic, and carcinogenic properties are thermostable fungal subordinate metabolites. OTs contamination can occur before or after harvesting, during the processing, packing, distribution, and storage of food. Mold development and mycotoxin contamination can occur in any crop or cereal that has not been stored properly for long periods of time and is subjected to high levels of humidity and temperature. Ochratoxin A (OTA) presents a significant health threat to creatures and individuals. There is also a concern of how human interaction with OTA will also express the remains of OTA from feedstuffs into animal-derived items. Numerous approaches have been studied for the reduction of the OTA content in agronomic products. These methods can be classified into two major classes: inhibition of OTA adulteration and decontamination or detoxification of food. A description of the various mycotoxins, the organism responsible for the development of mycotoxins, and their adverse effects are given. In the current paper, the incidence of OTA in various fodder and food materials is discussed, which is accompanied by a brief overview of the OTA mode of synthesis, physicochemical properties, toxic effects of various types of ochratoxins, and OTA decontamination adaptation methods. To our knowledge, we are the first to report on the structure of many naturally accessible OTAs and OTA metabolism. Finally, this paper seeks to be insightful and draw attention to dangerous OTA, which is too frequently neglected and overlooked in farm duplication from the list of discrepancy studies.

Immobilization of cellulase enzymes on nano and micro-materials for breakdown of cellulose for biofuel production-a narrative review.

Cellulose is a very abundant polymer that is found in nature. Cellulose has been used as a raw material for production of biofuels for many years. However, there are multiple processing steps that are required so that cellulose can be used as a raw material for biofuel production. One of the most important steps is the breakdown of cellulose into intermediate sugars which can then be a viable substrate for biofuel production. Cellulases are enzymes which play a role in the catalysis of the breakdown of cellulose into glucose. Nanomaterials and micromaterials have been gaining a lot of attention over the past few years for its potential in immobilizing enzymes for industrial procedures. Immobilization of enzymes on these nanomaterials has been observed to be of great value due to the improvement in thermal stability, pH stability, regenerative capacity, increase in activity and the reusability of enzymes. Similarly, there have been multiple reports of cellulase enzymes being immobilized on various nanoparticles. The immobilization of these cellulase enzymes have resulted in very efficient processing and provide a great and economic solution for the processing of cellulose for biofuel production. Hence in this paper, we review and discuss the various advantages and disadvantages of enzymes on various available nanomaterials.

Immobilization of Cu3(btc)2 on graphene oxide-chitosan hybrid composite for the adsorption and photocatalytic degradation of methylene blue.

The graphene oxide (GO)-based materials are appealing channels for water treatment, their separation from water for recycle remains a task. The Cu3(btc)2 (btc = benzene-1,3,5-tricarboxylic acid) metal organic framework (MOF) was covalently immobilized onto chitosan (CS)/graphene oxide (GO) to form a catalyst material, which was subjected to characterization by XRD, FTIR, SEM, TEM, BET, and UV-vis diffusive reflectance spectra. MOFs are permeable crystalline compounds consisting of metal ions and polyfunctional organic ligands. The structural characterization revealed that the Cu3(btc)2 and chitosan were incorporated into the graphene oxide structure. The adsorption of MB by GO-CS@Cu3(btc)2 catalyst was clearly defined by Langmuir isotherm and pseudosecond order kinetic model. GO-CS@Cu3(btc)2 was found to possess an adsorption capacity of ~357.15 mg/g. The findings displayed the probability of reusing the catalyst material for several photocatalytic processes. The GO-CS@Cu3(btc)2 catalyst material exhibited 98% degradation of MB within 60 min under UV irradiation. The obtained MB degradation results were fitted onto a Langmuir-Hinshelwood (L-H) plot. The GO-CS@Cu3(btc)2 catalyst material exhibited high degradation efficiencies at neutral pH conditions. The results have shown that the GO-CS@Cu3(btc)2 catalyst material can be used as a catalyst for adsorption and as a photocatalyst for the efficient degradation of methylene blue from aqueous solutions.

Nattokinase: an updated critical review on challenges and perspectives.

Natto, a fermented soybean food, has been consumed by oriental people for more than 1000 years. Nattokinase, formerly called subtilisin NAT is a well studied protease of microbial origin that possesses fibrinolytic (anti-clotting) activities. Due to its strong fibrinolytic and thrombolytic activity, Nattokinase is regarded as a precious dietary supplement or nutraceutical for the oral thrombolytic therapy. Nattokinase is witnessed to be a useful enzyme for the com-plete removal of the vitreous and associated proliferative tissues in proliferative vitreo retinal disorders. This review focuses on the native and recombinant Nattokinase from bacteria and other sources, their production, purification, immobilization and nano-immobilization studies, which aid in ameliorating their properties to suit the targeted industrial applications. Recent development in these fields are presented and discussed, and prospective developments are suggested.