RESUMEN
Solid waste generation is a huge contributor to environmental pollution issues, and food wastes are prominent in this category due to their large generation on a day-to-day basis. Thus, the settlement of daily food waste is one of the major constraints and needs innovative manufacturing sheme to valorize solid waste in sustainable manner. Moreover, these food wastes are rich in organic content, which has promising scope for their value-added products. In the present study, raw mango seed waste has been biotransformed to produce bacterial hydrolytic enzymes as feedstock. On investigating the impact of substrate, the highest bacterial cellulase production was recorded to be 18 IU/gds FP (filter paper) in 24 h of microbial incubation at 5 g of substrate in solid-state fermentation (SSF). Furthermore, at 40 °C and pH 6.0, 23 IU/gds FP enzyme could be produced in 24 h of SSF. Beside this, on comparing the influence of inorganic and organic nitrogen sources, urea has been found to provide better cellulase production, which yielded 28 IU/gds FP in 24 h of incubation, along with 77 IU/gds BG (ß-glucosidase) and 89 IU/gds EG (endoglucanase). On the other hand, Tween-40 and Tween-80, two different surfactants, were employed at a 1.0% concentration for 24 h of incubation. It was noticed that Tween-80 showed complete enzyme activity at 24 h, which was found to be relatively superior to that of Tween-40. This study may have potential utility in enzyme production using mango seed as a food waste for various industrial applications.
RESUMEN
Soil microbes are microscopic organisms that inhabit the soil and play a significant role in various ecological processes. They are essential for nutrient cycling, carbon sequestration, and maintaining soil health. Importantly, soil microbes have the potential to sequester carbon dioxide (CO2) from the atmosphere through processes like carbon fixation and storage in organic matter. Unlocking the potential of microbial-driven carbon storage holds the key to revolutionizing climate-smart agricultural practices, paving the way for sustainable productivity and environmental conservation. A fascinating tale of nature's unsung heroes is revealed by delving into the realm of soil microbes. The guardians of the Earth are these tiny creatures that live beneath our feet and discreetly work their magic to fend off the effects of climate change. These microbes are also essential for plant growth enhancement through their roles in nutrient uptake, nitrogen fixation, and synthesis of growth-promoting chemicals. By understanding and managing soil microbial communities, it is possible to improve soil health, soil water-holding capacity, and promote plant growth in agricultural and natural ecosystems. Added to it, these microbes play an important role in biodegradation, bioremediation of heavy metals, and phytoremediation, which in turn helps in treating the contaminated soils. Unfortunately, climate change events affect the diversity, composition, and metabolism of these microbes. Unlocking the microbial potential demands an interdisciplinary endeavor spanning microbiology, ecology, agronomy, and climate science. It is a call to arms for the scientific community to recognize soil microbes as invaluable partners in the fight against climate change. By implementing data-driven land management strategies and pioneering interventions, we possess the means to harness their capabilities, paving the way for climate mitigation, sustainable agriculture, and promote ecosystem resilience in the imminent future.
Asunto(s)
Ecosistema , Suelo , Suelo/química , Cambio Climático , Microbiología del Suelo , Monitoreo del AmbienteRESUMEN
The economic production of cellulase enzymes for various industrial applications is one of the major research areas. A number of broad industrial applications, for example, in cellulosic biomass hydrolysis for simple sugars such as glucose and subsequent biofuel production, make these enzyme systems the third most demanding enzymes. Nevertheless, due to their production on commercial substrates, cellulases fall into the category of costly enzymes. Therefore, the goal of the present work is to evaluate the enhancement of cellulase production and its utilization in the enzymatic hydrolysis of biomass using low-cost cellulosic substrate, which is abundant and widely available. In this context, waste biomasses of water hyacinth (WH), including leaves and stems, have been used as feedstock to produce cellulases via solid-state fermentation (SSF) in the current study, which improves its production as well as activity. Furthermore, the impact of process parameters like temperature and pH has been investigated for improved cellulase production. At optimum concentration using 10 g of feedstock, 22 IU/gds of FP, 92 IU/gds of BGL, and 111 IU/gds of EG have been noticed in day 5 of SSF. Herein, 40 °C has been identified as the optimum temperature for cellulase production, whereas 50-55 °C has been recorded as the optimum reaction temperature for cellulase enzyme activity. Additionally, pH 5.5 has been identified as the optimum pH for cellulase enzyme production, whereas this enzyme was thermally stable (55 °C) at pH 5.0 up to 3.5 h. Further, the cellulosic biomass hydrolysis of WH leaves via an optimized crude enzyme has been performed, and this could release 24.34 g/L of glucose in 24 h of the reaction. The current findings may have potential for developing cellulases for mass-scale production using WH-based waste bioresources for numerous biorefinery applications.
Asunto(s)
Celulasa , Celulasas , Eichhornia , Celulasas/metabolismo , Celulosa/metabolismo , Celulasa/metabolismo , Glucosa , Fermentación , HidrólisisRESUMEN
One of the most important properties of cellulolytic enzyme is its ability to convert cellulosic polymer into monomeric fermentable sugars which are carbohydrate by nature can efficiently convert into biofuels. However, higher production costs of these enzymes with moderate activity-based stability are the main obstacles to making cellulase-based applications sustainably viable, and this has necessitated rigorous research for the economical availability of this process. Using water hyacinth (WH) waste leaves as the substrate for cellulase production under solid state fermentation (SSF) while treating the fermentation production medium with CuO (cupric oxide oxide) bionanocatalyst have been examined as ways to make fungal cellulase production economically feasible. Herein, a sustainable green synthesis of CuO bionanocatalyst has been performed by using waste leaves of WH. Through XRD, FT-IR, SEM, and TEM analysis, the prepared CuO bionanocatalyst's physicochemical properties have been evaluated. Furthermore, the effect of CuO bionanocatalyst on the temperature stability of raw cellulases was observed, and its half-life stability was found to be up to 9 h at 65 °C. The results presented in the current investigation may have broad scope for mass trials for various industrial applications, such as cellulosic biomass conversion.
Asunto(s)
Celulasa , Eichhornia , Celulosa/metabolismo , Celulasa/química , Fermentación , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Banana peel waste is one of the major contributors in the issue raised from solid waste, however, it can be valorized effectively due to high content of cellulose and hemicellulose. Significant conversion of banana waste includes cellulolytic enzymes and bioenergy production. In the present study, bacterial cellulase was produced using raw banana peel and ripe banana peel under SSF. Additionally, impact of acid pretreatment was investigated as one of strategy to improve cellulolytic enzyme production. A comparative evaluation of raw and ripe banana peels showed that ripe banana peels showed better enzyme production after pretreatment with 0.5% dilute HCl acid. In the series of enhancement of the enzyme production, temperature and pH of the SSF medium were also investigated, and found temperature 35 °C and pH 6.0 were optimum to produce maximum 3.5-U/ml FPA, 39-U/ml BGL, and 54-U/ml EG in 18-h SSF incubation. The study presented eco-friendly waste management to produce industrial enzyme for its promising application in waste valorization and biorefinery area.
RESUMEN
The present investigation is targeted towards the facile fabrication of a carbon-based nanocatalyst (CNCs) using Kans grass biomass (KGB) and its sustainable application in microbial cellulase enhancement for the alleviation of enzymatic hydrolysis for sugar production. Different pretreatments, including physical, KGB extract-mediated treatment, followed by KOH pretreatment, have been applied to produce CNCs using KGB. The presence of CNCs influences the pretreatment of KGB substrate, fungal cellulase production, stability, and sugar recovery in the enzymatic hydrolysis of KGB. Using 1.0% CNCs pretreated KGB-based solid-state fermentation, 33 U/gds FPA and 126 U/gds BGL were obtained at 72 h, followed by 107 U/gds EG at 48 h in the presence of 0.5% CNCs. Further, 42 °C has been identified as the optimum temperature for cellulase production, while the enzyme showed thermal stability at 50 °C up to 20 h and produced 38.4 g/L sugar in 24 h through enzymatic hydrolysis of KGB.
Asunto(s)
Celulasa , Poaceae , Poaceae/metabolismo , Azúcares , Carbohidratos , Celulasa/metabolismo , Temperatura , Hidrólisis , Fermentación , BiomasaRESUMEN
Solid wastes are the major contributors in global environmental pollution and their management is the need of urgency towards development of sustainable world. In the present work, solid waste of potato peels has been used as feedstock for fermentation of bacterial cellulase production and substrate for enzymatic hydrolysis via this enzymes cocktail. Additionally, liquid extracts of pea pod and root of water hyacinth wastes have been used to complete nutritional requirements and moisture balance in SSF process during the course of enzyme production. At optimum feedstock concentration of 6.0 g PPW and 10:40 extract-based moisture ratio of WHR and Ppw, Bacillus sp. produced 15 U/gds FP in 18 h, whereas maximum 36 U/gds BGL and 42 U/gds EG have been recorded in 24 h of SSF. Temperature 35 °C and pH 5.5 were optimum for enzyme production while the produced enzyme was thermally stable upto 30 h at 35 °C with 100% pH stability upto 14 h and 77% relative activity at 34 h. The optimized bacterial enzymes have been used for bioconversion of PPW biomass and 26 g/L glucose has been recorded at a hydrolytic temperature of 50 °C and pH 5.0. The study may have feasible promising scope in cellulosic biorefineries and waste management.
RESUMEN
Due to the limited availability of fossil fuels, pollution causing serious environmental issues, and their continuously rising price, the development of low-cost efficient enzymes and their implementation in biomass-based bioenergy industries are highly demanded. In the present work, phytogenic fabrication of copper oxide based nanocatalyst has been performed using moringa leaves and has been characterized using different techniques. Herein, the impact of different dosages of as-prepared nanocatalyst on fungal co-cultured cellulolytic enzyme production under co-substrate fermentation using wheat straw and sugarcane bagasse in 4:2 ratios in solid state fermentation (SSF) has been investigated. An optimal concentration of 25 ppm of nanocatalyst influenced the production of 32 IU/gds of enzyme, which showed thermal stability at 70 °C for 15 h. Additionally, enzymatic bioconversion of rice husk at 70 °C librated 41 g/L of total reducing sugars, which led to the production of 2390 mL/L of cumulative H2 in 120 h.
Asunto(s)
Moringa oleifera , Saccharum , Celulosa/metabolismo , Moringa oleifera/metabolismo , Cobre , Saccharum/metabolismo , Fermentación , ÓxidosRESUMEN
Microbial cellulases are the enzymes used in numerous industrial biotechnological applications. Efficiency of celluloytic cocktails plays a key role in the conversion of biomass into biofuels, but limited production, high cost and low efficiency are the main obstacles to sustainable biorefining. The current work aims to establish a feasible approach for boosting the production of fungal endoglucanse (EG) and its functional stability utilizing nanocomposite materials based on manganese oxide. Herein, aqueous extract from mixed fruit waste was used to synthesize the nanocomposite sample, which was subsequently subjected to several characterization techniques for analysis. Following the solid-state fermentation of paddy straw, and by employing 75 mg nanocomposite, 192 IU/gds EG was produced under the optimal conditions, while 19 IU/gds FP and 98 IU/gds BGL production were recorded. The crude EG enzyme treated with nanocomposite also shows complete stability at pH 5.0 for 3.5 h while retaining thermal activity at 70 °C for 4 h.
Asunto(s)
Celulasas , Frutas , Porosidad , Óxidos , FermentaciónRESUMEN
In the present work, kinetic study has been conducted in order to effectively eliminate the p-cresol from wastewater employing isolated bacterial strain Serratia marcescens ABHI001 under batch shake flasks in the concentration varying from 50 to 500 mg/L. Further, effects of various parameters including p-cresol concentration, inoculum dosage, temperature, pH and agitation have been investigated. It was found that 10% v/v inoculum of 24 h age, was effective in degrading p-cresol. Beside this, it was noticed that the concentration of P-cresol above 100 mg/L exhibited an inhibitory effect. The maximum specific growth rate (µmax) was obtained to be 0.360 h-1 for 100 mgL-1 concentration. Further, the experimental results were well fitted with Halden's and Andrew's models and kinetic parameters µmax, KS and Ki in case of Haldane model were calculated to be 0.9697 h-1, 88.07 mgL-1 and 219.9 mgL-1, respectively whereas the corresponding values in case of Andrews's constants were 0.6917 h-1, 62.83 mgL-1 and 307.4 mgL-1, respectively. The yield coefficient for the growth on p-cresol was found to be 0.82.
Asunto(s)
Contaminantes Ambientales , Purificación del Agua , Aguas Residuales , Biodegradación Ambiental , Serratia marcescens/metabolismo , Fenoles/metabolismoRESUMEN
Water resources in India's Indo-Gangetic plains are over-exploited and vulnerable to impacts of climate change. The unequal spatial and temporal variation of meteorological, hydrological and hydrogeological parameters has created additional challenges for field engineers and policy planners. The groundwater and surface water are extensively utilized in the middle Gangetic plain for agriculture. The primary purpose of this study is to understand the discharge and recharge processes of groundwater system using trend analysis, and surface water and groundwater interaction using groundwater modelling. A comprehensive hydrological, and hydrogeological data analysis was carried out and a numerical groundwater model was developed for Bhojpur district, Bihar, India covering 2395 km2 geographical area, located in central Ganga basin. The groundwater level data analyses for the year 2018 revealed that depth to water level varies from 3.0 to 9.0 meter below ground level (m bgl) in the study area. The M-K test showed no significant declining trend in the groundwater level in the study area. The groundwater modelling results revealed that groundwater head is higher in the southern part of the district and the groundwater flow direction is from south-west to north-east. The groundwater head fluctuation between the monsoon and the summer seasons was observed to be 2 m, it is also witnessed that groundwater is contributing more to rivers in the monsoon season in comparison with other seasons. Impact of reduction in pumping on groundwater heads was also investigated, considering a 10% reduction in groundwater withdrawal. The results indicated an overall head rise of 2 m in the southern part and 0.2-0.5 m in the middle and northern part of the district.
Asunto(s)
Agua Subterránea , Agua , Monitoreo del Ambiente/métodos , Ríos , Abastecimiento de AguaRESUMEN
Peanut shell biomass was selected and utilized to produce biochar through pyrolysis under N2 atmosphere at 923 K. After studying various effects of experimental parameters and by statistical modeling and optimization by RSM using Box-Benken design, optimized conditions of pH 2.0 ± 0.1, temperature 303 K, and adsorbent dose used of 2.5 g L-1 were obtained giving almost 99.99% removal for Cr(VI) from the solution. FESEM, FTIR, XRD, XPS, EDX, elemental mapping, and pHzpc were used for the evaluation of the surface characteristics of peanut shell biochar (PSB). Studies revealed C-O, C-H, CO, and O-H functional groups' presence with the help of FTIR, majorly in control of adsorption mechanism and the EDX confirmed the presence of Cr(VI) onto peanut shell biochar (PSB). Further adsorption mechanism for Cr(VI) adsorption followed the pseudo-second-order rate with adsorption capacity of 29.38 mg g-1 given by the Langmuir isotherm. The thermodynamic study confirmed the exothermic and spontaneous nature of the process for Cr(VI) adsorption onto PSB. The adsorption mechanism showed electrostatic attraction, reduction, and complexation mainly responsible for Cr(VI) adsorption by PSB. Thus, PSB effectively removes Cr(VI) is confirmed by the present study.
Asunto(s)
Arachis , Contaminantes Químicos del Agua , Carbón Orgánico , Cromo , AguaRESUMEN
Biogas-based circular bioeconomy can provide a long-term way out of the organic fraction of municipal solid waste. The barriers to biogas production are obstructing the growth of the biogas-based circular bioeconomy. This study provides a comprehensive analysis of the barriers to biogas in developing countries for the wider implementation of biogastechnology. Twenty barriers are identified and categorized into technical, logistical, institutional, and social dimensions. The analytical hierarchy process is applied to rank the barriers. The result of barrier ranking shows that the lack of appropriate segregation facilities is the most crucial barrier, followed by waste characteristics variation, and inconsistent supply. This study will provide an outline for rational decision-making in the sustainable organic fraction of municipal waste management.
Asunto(s)
Eliminación de Residuos , Administración de Residuos , Biocombustibles/análisis , Eliminación de Residuos/métodos , Residuos Sólidos/análisis , Administración de Residuos/métodosRESUMEN
Biogas production through anaerobic digestions of organic wastes using microbes is a potential alternative to maintain the long term sustainability of the environment and also to full-fill the energy demands and waste management issues. In this context, pressmud can be a vital substrate which is generated from sugarcane industries and found to be broadly available. In this work, biogas improvement has been investigated in presence of CuO/Cu2O based nanocatalyst wherein pressmud is employed as a substrate in anaerobic digestion. Herein, CuO/Cu2O based nanocatalyst has been prepared using the aqueous extract prepared from the combination of PM and SCB which is employed as a reducing agent. The physicochemical properties of CuO/Cu2O nanocatalyst have been probed through different techniques and it is noticed that using 1.0 % CuO/Cu2O based nanocatalyst employed in AD process, cumulative biogas 224.7 mL CH4 /g VS could be recorded after 42 days.
Asunto(s)
Biocombustibles , Saccharum , Anaerobiosis , Reactores Biológicos , Celulosa , Cobre , Digestión , Grano Comestible/química , Metano/análisis , Saccharum/químicaRESUMEN
The finite nature, regional availability, and environmental problems associated with the use of fossil fuels have forced all countries of the world to look for renewable eco-friendly alternatives. Agricultural waste biomasses, generated through the cultivation of cereal and noncereal crops, are being considered renewable and viable alternatives to fossil fuels. In view of this, there has been a global spurt in research efforts for using abundantly available agricultural wastes as feedstocks for obtaining energy and value-added products through biochemical and thermal conversion routes. In the present work, the thermochemical characteristics and thermal degradation behavior of sugarcane leaves (SCL) and tops were studied. The batch pyrolysis was carried out in a fixed-bed tubular reactor to obtain biochar, bio-oil, and pyrolytic gas. Effects of bed height (4-16 cm), particle size (0.180-0.710 mm), heating rate (15-30 °C/min), and temperature (350-650 °C) were investigated. The maximum yields of bio-oil (44.7%), biogas (36.67%), and biochar (36.82%) were obtained at 550, 650, and 350 °C, respectively, for a 16 cm deep bed of particles of size 0.18-0.30 mm at the heating rate of 25 °C/min. The composition of bio-oil was analyzed using Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H NMR), and gas chromatography-mass spectrometry (GC-MS) techniques. Several aliphatic, aromatic, phenolic, ketonic, and other acidic compounds were found in the bio-oil. The biochar had a highly porous structure and several micronutrients, making it useful as a soil conditioner. In the middle temperature ranges, biogas had more methane and CO and less hydrogen, but at higher temperatures, hydrogen was predominant.
RESUMEN
Biohydrogen production using renewable sources has been regarded as one of the most sustainable ways to develop low-cost and green production technology. In order to achieve this objective, herein biohydrogen production has been conducted using the combination of untreated secondary sewage sludge (Sss), algal biomass hydrolyzate (Abh), graphene oxide (GO) and bacterial consortia that forms a granular system. Thus, naturally formed granular system produced cumulative H2 of 1520 mL/L in 168 h with the maximum production rate of 13.4 mL/L/h in 96 h at initial pH 7.0, and optimum temperature of 37 °C. It is noticed that the combination of Abh, Sss and GO governed medium showed 42.05 % higher cumulative H2 production along with 22.71 % higher production rate as compared to Abh and Sss based H2 production medium. The strategy presented herein may find potential applications for the low-cost biohydrogen production using waste biomasses including Sss and Abh.
Asunto(s)
Reactores Biológicos , Aguas del Alcantarillado , Bacterias , Reactores Biológicos/microbiología , Fermentación , Grafito , Hidrógeno , Aguas del Alcantarillado/microbiologíaRESUMEN
The iron impregnated fungal bio-filter (IIFB) discs of luffa sponge containing Phanerochaete chrysosporium mycelia have been used for the removal of As(III) from water. Two different forms of same biomass viz. free fungal biomass (FFB) and modified free fungal biomass (chemically modified and iron impregnated; CFB and IIFB) have been simultaneously investigated to compare the performance of immobilization, chemo-tailoring and iron impregnation for remediation of As(III). IIFB showed highest uptake capacity and percentage removal of As(III), 1.32 mg/g and 92.4% respectively among FFB, CFB and IIFB. Further, the application of RSM and ANN-GA based mathematical model showed a substantial increase in removal i.e. 99.2% of As(III) was filtered out from water at optimised conditions i.e. biomass dose 0.72 g/L, pH 7.31, temperature 42 °C, and initial As(III) concentration 1.1 mg/L. Isotherm, kinetic and thermodynamic studies proved that the process followed monolayer sorption pattern in spontaneous and endothermic way through pseudo-second order kinetic pathway. Continuous mode of As(III) removal in IIFB packed bed bioreactor, revealed increased removal of As(III) from 76.40 to 88.23% with increased column height from 5 to 25 cm whereas the removal decreased from 88.23 to 69.45% while increasing flow rate from 1.66 to 8.30 mL/min. Moreover, the IIFB discs was regenerated by using 10% NaOH as eluting agent and evaluated for As(III) removal for four sorption-desorption cycles, showing slight decrease of their efficiency by 1-2%. SEM-EDX, pHzpc, and FTIR analysis, revealed the involvement of hydroxyl and amino surface groups following a non-electrostatic legend exchange sorption mechanism during removal of As(III).
Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Biomasa , Concentración de Iones de Hidrógeno , Hierro , Cinética , Termodinámica , Agua , Contaminantes Químicos del Agua/metabolismoRESUMEN
Cellulase enzymes have wide range of industrial application, but high production cost and relatively low efficiency are the main issues, which are needed to resolve. Substrate is known as the main contributor which can bring down the production cost of these enzymes at large scale. Therefore, in the present study, corn cob (Cc) waste has been employed as a potential substrate to produce efficient and good amount of cellulase using the bacterial strain Bacillus subtilis. Under the influence of optimal parameters while using the optimum concentration of Cc (7.0 g), maximum 12 IU/gds FP, 97 IU/gds BGL and 129 IU/gds EG have been recorded. Additionally, crude enzyme showed maximum FP activity of 14 IU/gds using 1.0 g/L peptone employed as the optimum organic nitrogen source. The bacterial cellulase exhibits temperature tolerance ability at 55 °C, and retains its half-life activity for 5 h and pH tolerance at pH 7.0 up to 55% of the relative activity. The results recorded in the present study may have potential for the large-scale and low-cost bacterial cellulase production using cellulose rich substrate e.g. Cc waste that can be vital for numerous industrial applications.