Solid-state Fermentation For Production Research Articles

Chemical constituents from the medicinal herb-derived fungus Chaetomium globosum Km1226

BackgroundEndophytic fungi have proven to be a rich source of novel natural products with a wide-array of biological activities and higher levels of structural diversity.ResultsChemical investigation on the liquid- and solid-state fermented products of Chaetomium globosum Km1226 isolated from the littoral medicinal herb Atriplex maximowicziana Makino resulted in the isolation of compounds 1–14. Their structures were determined by spectroscopic analysis as three previously undescribed C13-polyketides, namely aureonitol C (1), mollipilins G (2), and H (3), along with eleven known compounds 4–14. Among these, mollipilin A (5) exhibited significant nitric oxide production inhibitory activity in LPS-induced BV-2 microglial cells with an IC50 value of 0.7 ± 0.1 µM, and chaetoglobosin D (10) displayed potent anti-angiogenesis property in human endothelial progenitor cells (EPCs) with an IC50 value of 0.8 ± 0.3 µM.ConclusionsThree previously unreported compounds 1–3 were isolated and identified. Mollipilin A (5) and chaetoglobosin D (10) could possibly be developed as anti-inflammatory and anti-angiogenic lead drugs, respectively.

Insights into the Dynamic Succession of Microbial Community and Related Factors of Vanillin Content Change Based by High-Throughput Sequencing and Daqu Quality Drivers.

Daqu is an important saccharifying starter in the fermentation of Nongxiangxing Baijiu in China. Vanillin is a health and flavor factor in Baijiu. However, only a few research studies on the vanillin content of Daqu are currently not systematic. In order to investigate the metabolic mechanism of vanillin in the fermentation process of Daqu, we analyzed the changes in microorganisms, influencing factors, and enzymes related to vanillin in Daqu. This research found that there were differences between bacterial and fungal genera in each sample, and the abundance of bacteria was greater than that of fungi. Among the microbial genera, Klebsiella, Escherichia, Acinetobacter, Saccharopolyspora, Aerococcus, and Puccinia were positively correlated with vanillin. Meanwhile, we also found that moisture and reducing sugar were the main physicochemical factors affecting the formation of vanillin. The functional annotation results indicate that carbohydrate metabolism and energy metabolism were important microbial metabolic pathways that impacted vanillin production in solid-state fermentation. The feruloyl-CoA hydratase/lyase (EC 4.1.2.61) and acylamidase (EC 3.5.1.4) were positively correlated with vanillin content (p ≤ 0.05) and promote the increase in vanillin content. These findings contribute to furthering our understanding of the functional microorganisms, physicochemical factors, and enzymes related to the change in vanillin content during the fermentation of Daqu and can help to further explore the flavor substances in Baijiu fermentation in the future.

Solid-state fermentation production of L-lysine by Corynebacterium glutamicum (ATCC 13032) using agricultural by-products as substrate.

To meet the growing demand for L-lysine, an essential amino acid with various applications, it is crucial to produce it on a large scale locally instead of relying solely on imports. This study aimed to evaluate the potential of using Corynebacterium glutamicum ATCC 13032 for L-lysine production from agricultural by-products such as palm kernel cake, soybean cake, groundnut cake, and rice bran. Solid-state fermentation was conducted at room temperature for 72h, with the addition of elephant grass extract as a supplement. The results revealed that these agricultural by-products contain residual amounts of L-lysine. By employing solid-state fermentation with C. glutamicum (106 CFU/ml) in 100g of various agricultural by-products, L-lysine production was achieved. Interestingly, the addition of elephant grass extract (1g of elephant grass: 10 ml of water) further enhanced L-lysine production. Among the tested substrates, 100g of groundnut cake moistened with 500 ml of elephant grass extract yielded the highest L-lysine concentration of 3.27 ± 0.02 (mg/gds). Furthermore, fermentation led to a substantial rise (p < 0.05) in soluble protein, with solid-state fermented soybean cake moistened with 500 ml of elephant grass extract exhibiting the highest amount of 7.941 ± 0.05mg/gds. The activities of xylanase, amylase and protease were also significantly enhanced. This study demonstrates a viable biotechnological approach for locally producing L-lysine from agricultural by-products using solid-state fermentation with C. glutamicum. The findings hold potential for both health and industrial applications, providing a sustainable and economically feasible method for L-lysine production.

Valorization of Macuba (Acronia aculeata) for Integrated Production of Lipase by Yarrowia lipolytica and Biodiesel Esters

Enzymatic biodiesel production is a potential eco-friendly alternative to the conventional chemical route which requires extensive study to reduce the costs associated with the application of commercial enzymes. Thus, this study aimed to develop a bioprocess using residues from macauba (Acrocomia aculeata) as raw material for lipase production in solid-state fermentation (SSF) by Yarrowia lipolytica. Then, the product obtained was used as a biocatalyst for the conversion (hydrolysis/esterification) of macauba acidic oil to biodiesel esters. Firstly, different SSF parameters (inoculum concentration, initial moisture content, and carbon and nitrogen levels) were investigated in a factorial design approach, using the cake from macauba fruit. Afterwards, moisture and urea concentration were shown to be statistically significant variables for lipase production. Lipase productnivities were 12.6 ± 0.6 U g−1 h−1 (at 24 h) for macauba fruit cake and 11.6 ± 1 U g−1 h−1 (at 20 h) for macauba pulp and peel cake. The solid enzymatic preparation (biocatalyst) showed optimized values at pH 6–7 at 37 °C, remaining stable (&gt;70% retention) for 90 days at room temperature. Finally, enzymatic hydrolysis of the acidic oil from macauba reached 96% conversion (72 h) to fatty acids, and esterification of fatty acids reached 72% (biodiesel yield of 67%). The bioprocess described is a promising alternative for an integral and self-sufficient valorization of the macauba products.

A specific and rapid method for detecting Bacillus and Acinetobacter species in Daqu.

Daqu is a spontaneous, solid-state cereal fermentation product used for saccharification and as a starter culture for Chinese Baijiu production. Bacillus and Acinetobacter, two dominant microbial genera in Daqu, produce enzymes and organic acids that influence the Daqu quality. However, there are no rapid analytical methods for detecting Bacillus and Acinetobacter. We designed primers specific to the genera Bacillus and Acinetobacter to perform genetic comparisons using the 16S rRNA. After amplification of polymerase chain reaction using specific primers, high-throughput sequencing was performed to detect strains of Bacillus and Acinetobacter. The results showed that the effective amplification rates for Bacillus and Acinetobacter in Daqu were 86.92% and 79.75%, respectively. Thus, we have devised and assessed a method to accurately identify the species associated with Bacillus and Acinetobacter in Daqu, which can also hold significance for bacterial typing and identification.

Effect of Purpureocillium lilacinum on inter-root soil microbial community and metabolism of tobacco

BackgroundNumerous chemical pesticides have been used in agricultural production to combat crop diseases and pests. Despite ensuring certain economic advantages, they have also resulted in issues like environmental contamination, declining soil quality, and pesticide residues. Because biological control is environmentally friendly and difficult to acquire resistance to, it has been used in practice recently.MethodsIn this study, we isolated the endophytic fungus Purpureocillium lilacinum from Portulaca oleracea L., which was previously found to have inhibitory effects on soil pathogens in tobacco fields. To find out how the biocontrol agent P. lilacinum affects soil microorganisms and plant metabolism in tobacco cultivation, we used amplicon sequencing technology and gas chromatography-mass spectrometry to look at the structure of soil microbial communities and the networks of interactions between microorganisms and metabolites in the inter-rhizosphere soil of tobacco fields treated with different amounts of P. lilacinum.ResultsThe findings showed that there was a trend toward less microbial diversity among inter-root microorganisms as solid-state fermentation (SSF) products of P. lilacinum increased; however, submerged fermentation (SmF) had no discernible impact on microbial diversity when compared to the direct use of SSF. Additionally, the relationship between inter-root fungi and volatile compounds in tobacco leaves was dominated by a negative correlation.ConclusionsThe result demonstrated that P. lilacinum’s antagonistic interaction in the inter-rhizosphere microbial community was dominant and valuable for biopesticide application. P. lilacinum can work more effectively on tobacco roots by using SSF products. P. lilacinum’s opposition to fungal colonies may enhance the volatile chemicals in tobacco leaves. These provide some implications for the biocontrol application of P. lilacinum.

Enzymatic One-Pot Hydrolysis of Extracted Sugar Beet Press Pulp after Solid-State Fermentation with an Engineered Aspergillus niger Strain

Extracted sugar beet press pulp (SBPP) is a promising agricultural residue for saccharification and further bioconversion. Combining solid-state fermentation of SBPP with engineered Aspergillus niger for enzyme production followed by hydrolysis of additionally added SBPP in the same bioreactor was studied to produce a sugar solution (hydrolysate) in a one-pot process. The initial aerobic solid-state fermentations were carried out in duplicate on non-milled, wet SBPP (moisture content of 72% (w/v)) with an A. niger strain engineered for constitutive pectinase production for 96 h, and this resulted in polygalacturonase activities of up to 256 U mL−1 in the wet media. Afterwards, water was added to the bioreactor, and the remaining solids were suspended by stirring to dissolve the hydrolytic enzymes. Metabolic activities of A. niger were inactivated by a N2-atmosphere and by increasing the temperature to 50 °C. High solid loads of milled SBPP were added to the stirred-tank reactor with a delay of 24 h to enable sugar yield calculations based on the compositional analysis of the SBPP used. The resulting final sugar concentrations of the hydrolysate after 166 h were 17 g L−1 d-glucose, 18.8 g L−1 l-arabinose, and 12.5 g L−1 d-galacturonic acid, corresponding to sugar yields of 98% d-glucose, 86% l-arabinose, and 50% d-galacturonic acid, respectively. Including the other sugars released during enzymatic hydrolysis in the one-pot process (d-xylose, d-mannose, d-galactose), a total sugar concentration of 54.8 g L−1 was achieved in the hydrolysate. The one-pot process combining hydrolytic enzyme production in solid-state fermentation with high solid loads during enzymatic hydrolysis of the milled SBPP reduces hydrolytic process costs by replacing chemical pre-treatments, enabling the in situ production of SBPP-adapted hydrolytic enzymes, as well as avoiding intermediate enzyme extraction and preparation steps.

Optimization of Esterase Production in Solid-State Fermentation of Agricultural Digestate

The continuous increase in biogas production poses the need for innovative applications for its by-products. Solid-state fermentation (SSF) has regained attention in the development of several products because of the possibility to use low-cost and easily available substrates, such as organic wastes. SSF represents a valuable process for agricultural digestate valorization in terms of enzyme production. In the present study, cellulase and esterase were produced by Trichoderma asperellum R on a digestate-based substrate in SSF, with esterase as the highest obtained activity. After assessing the effect of light on it, the esterase production in SSF was optimized using response surface methodology. The influence of substrate composition, temperature and humidity on the enzyme production was evaluated on two sets of data generated based on digestate concentration (50% and 70% w/w). The statistical analyses revealed that these parameters affected esterase production only when Trichoderma asperellum grew on substrate containing 50% w/w of digestate. The best esterase activity (264.6 mU/mg total protein) was achieved with the following optimized SSF parameters: 50% digestate, 50% fruits, 10% sawdust, 30 °C. The current finding of esterase production on digestate-based substrates makes the SSF method presented here a sustainable and completely circular technology.

Addition of solid-state fermentation product of yeast ameliorated the effects of high-fat diet on hepatic lipid metabolism, epidermal mucus, intestine and liver health, and gut microbiota of zebrafish

To assessed the effects of solid-state fermentation product of yeast (SFPY) supplementation on high-fat diet (HFD) induced challenges on growth, hepatic lipid metabolism, epidermal mucus, intestine and liver health and gut microbiota in zebrafish (Danio rerio), four experimental diets were prepared for one-month-old zebrafish: basal diet (Control), high-fat diet (HFD), 0.5% SFPY (0.5 SFPY) or 1.0% SFPY (1.0 SFPY)-added HFD. After 3 weeks of feeding, the results illustrated that although HFD increased weight gain (WG), corresponding decreased the feed conversation ratio (FCR), it caused negative influences including liver steatosis, intestinal and liver damage in zebrafish. Compared with HFD group, 1.0% SFPY obviously promoted the lysozyme activity and complement 4 (C4) level on epidermal mucus (P < 0.05), and significantly reduced liver TAG (P < 0.05). Addition of SFPY significantly decrease the lipid synthesis-related genes including C/EBPα, FAS, PPARγ, ACC1, DGAT2 and pro-inflammatory factors including IL-6, IL-1β in liver (P < 0.05), significantly increased the height of gut villi (P < 0.05). Moreover, the 1.0 SFPY group significantly reduced the abundance of gut microbiota concluding Proteobacteria, Fusobacteriota, Planctomycetota and improved the abundance of gut Actinobacteriota and Firmicutes (P < 0.05). To sum up, the addition of SFPY significantly ameliorated hepatic inflammation and intestinal damage caused by high-fat diet, and positively affected the intestinal microbiota composition of zebrafish.

Metabolite Chemical Composition of the Bletilla striata (Thunb.) Reichb. f. Endophyte Penicillium oxalicum

Penicillium oxalicum strain can be isolated from the Bletilla striata (Thunb.) Reichb. f. tubers. Its solid-state fermentation products are concentrated by percolation extraction. Separation and purification have been conducted to the ethyl acetate extracts by preparative HPLC. Based on the use of spectrometry, we have determined 17 known compounds, 12,13-dihydroxy-fumitremorgin C (1), pseurotin A (2), tyrosol (3), cyclo-(L-Pro-L-Val) (4), cis-4-hydroxy-8-O-methylmellein (5), uracil (6), cyclo-(L-Pro-L-Ala) (7), 1,2,3,4-tetrahydro-4-hydroxy-4-quinolin carboxylic acid (8), cyclo-(Gly-L-Pro) (9), 2'-deoxyuridine (10), 1-(β-D-ribofuranosyl)thymine (11), cyclo-(L-Val-Gly) (12), 2'-deoxythymidine (13), cyclo-(Gly-D-Phe) (14), cyclo-L-(4-hydroxyprolinyl)-D-leucine (15), cyclo-(L)-4-hydroxy-Pro-(L)-Phe (16), uridine (17). Here, we report compounds 1–3, 5, 7–8, 11–12, 14–17 are first found and isolated from this endophyte.

Production of itaconic acid from sweet potato (Ipomoea batata) peel using naturally occurring fungi in solid state fermentation

This study evaluates the potentials of sweet potato peel as a substrate for itaconic acid production in solid state fermentation using naturally occurring fungi. Sweet potato peel was analyzed for proximate composition using standard methods. Fungi were obtained from the peel by solid state fermentation and identified using microscopic and molecular methods. Fermentation for itaconic acid production was done using isolated fungus and Aspergillus niger (ATCC 16888) was used as control. Optimization of fermentation parameters was carried out using standard procedures. Assay for itaconic acid and total titratable acidity (TTA) were analyzed using standard methods. Reducing sugar was obtained using DNSA method. Proximate composition of the peel reveals carbohydrate content to be 79%, protein, 5% and ash, 4%. Fungus isolated was identified as Aspergillus flavus L-2482/2012. Highest itaconic acid production by A. flavus was 7.74±0.00 mg/ml on day 5 at 30 g substrate concentration. Using 2 ml of 1 x 107 spores/ml, A. flavus and A. niger produced 6.97±0.13 and 6.67±0.09 mg/ml respectively. Optimum temperature for itaconic acid production was 30°C for A. niger and A. flavus. TTA ranged between 0.04±0.00 to 0.21±0.01 and 0.05±0.00 to 0.26±0.00 mg/ml for A. niger and A. flavus respectively. The highest reducing sugar, 0.51±0.00 mg/ml was obtained at substrate concentration 40 mg/ml on day 5 by A. flavus while A. niger had reducing sugar value of 0.37±0.00 mg/ml. In conclusion, A. flavus L-2482/2012. has great potentials for itaconic acid production using sweet potato peel in solid state fermentation under optimized conditions.

Synergistic effects of ternary mixture formulation and process parameters optimization in a sequential approach for enhanced L-asparaginase production using agro-industrial wastes

A novel ternary mixture of inexpensive and nutrient-rich agro-substrates comprising groundnut de-oiled cake, corn gluten meal, and soybean meal has been explored to enhance the L-asparaginase production in solid-state fermentation. To achieve the aim, a hybrid strategy was implemented by utilizing a combination of a mixture design and artificial neural networks. The study initiated with the judicious selection of the agro-substrates based on their low C/N content in comparison to the control using the CHNS elemental analysis. The mixture composition of soybean meal (49.0%), groundnut de-oiled cake (31.5%), and corn gluten meal (19.5%) were found optimum using the simplex lattice mixture design. The agro-industrial substrates mix revealed synergistic effects on the L-asparaginase production than either of the substrates alone. The maximum L-asparaginase activity of 141.45 ± 5.24IU/gds was observed under the physical process conditions of 70% moisture content, autoclaving period of 30min and 6.0 pH by adopting the machine learning-derived artificial neural network (ANN) methodology. The ANN modeling showed excellent prediction ability with a low mean squared error of 0.7, a low root mean squared error of 0.84, and a high value of 0.99 for regression coefficient. Moisture content (%) was assessed to be the most sensitive process parameter in the global sensitivity analysis. The net outcome from the two sequential optimization designs is the selection of the ideal mixture composition followed by the optimum physical process parameters. The application of the enzyme demonstrated significant cytotoxicity against leukemia cell line and therefore exhibited an anti-cancer effect. The present study reports a novel mixture combination and methodology that can be used to lower the cost and enhance the production of L-asparaginase using an agro-industrial substrate mixture.

Coconut waste valorization to produce biochar catalyst and its application in cellulose-degrading enzymes production via SSF

Solid waste management and waste valorization are key concerns and challenges around the globe. Solid wastes generated by food industries are found in a diverse variety, are key sources of enormously valuable compounds, and can be effectively transformed into useful products for broad industrial applications. Biomass-based catalysts, industrial enzymes, and biofuels are some of the very prominent and sustainable products that are developed using these solid wastes. The aims of the current study are therefore centered on the multiple valorizations of coconut waste (CWs) to develop biochar as a catalyst and its application in fungal enzyme production in solid-state fermentation (SSF). Biochar as a catalyst using CWs has been prepared via a calcination process lasting 1 h at 500 °C and characterized through X-ray diffraction, Fourier-transformed infrared spectroscopy, and scanning electron microscope techniques. The produced biochar has been implemented for boosting enzyme production through SSF. In addition, studies have been performed on enzyme production with varying time and temperature, and it is found that the maximum 92 IU/gds BGL enzyme could be produced at a 2.5 mg concentration of biochar-catalyst at 40 °C in 72 h.

Optimisation of alpha-amylase inhibitor production in solid state fermentation.

Though not a known producer of alpha-amylase inhibitor, the potential of Streptomyces xinghaiensis AAI-2 to produce this important metabolite was assessed and the process optimised in solid substrate using response surface methodology. The isolate was grown in an inoculum medium, inoculated into wheat bran and supplemented with a basal medium for production of alpha amylase inhibitor. Optimum conditions were determined by Response Surface Methodology. The extract was recovered using sodium phosphate buffer at refrigerated temperature and assay for the presence of alpha-amylase inhibitor was carried out by Dinitrosalicylic acid method. Based on the results of the experimental trials and iteration with those values, it was predicted that optimal pH for alpha-amylase inhibitor production using S. xinghaiensis in solid culture of wheat bran was pH 6.4-6.9 while optimal moisture content and incubation time were predicted as 71%-73% and 9-12days respectively.

Application of the novel manta-ray foraging algorithm to optimize acidic peptidase production in solid-state fermentation using binary agro-industrial waste

Peptidases, which constitute about 20% of the global enzyme market, have found applications in detergent, food and pharmaceutical industries, and could be produced on a large scale using low-cost agro-industrial waste. An acidophilic Bacillus cereus strain produced acidic peptidase on binary-agro-industrial waste comprising yam peels and fish processing waste at pH 4.5 with high catalytic activity. A five-variable central composite rotatable design of a response surface methodology was used to model bioprocess conditions for improved peptidase production in solid-state fermentation. Data generated was leveraged as the basis for applying the novel Manta-ray foraging optimization-linked feed-forward artificial neural network to predict bioprocess conditions optimally. Results obtained from the optimization experiments revealed a significant coefficient of determination of 0.9885 with low-performance error. The bioprocess predicted a peptidase activity of 1035.32 U/mL under optimized conditions set as 54.8 g/100 g yam peels, 23.85 g/100 g fish waste, 0.31 g/100 g CaCl2, 47.54% (v/w) moisture content, and pH 2. Peptidase activity was improved 5-fold, and was stable for 240 min between pH 2.5 and 3.5. Michaelis-Menten kinetics revealed a Km of 0.119 mM and a catalytic efficiency of 45462.19 mM−1 min−1. The bioprocess holds promise for sustainable enzyme-driven applications.

Gradually supply of isoamyl alcohol increases the isoamyl acetate production in solid-state fermentation.

Nowadays, isoamyl acetate production is carried out by chemical synthesis with a recent interest in developing biological producing processes, mainly based on microorganisms in submerged fermentation. This work assayed producing isoamyl acetate through solid-state fermentation (SSF), feeding the precursor in the gas phase. Polyurethane foam functioned as the inert support to contain 20ml of a solution of molasses (10%w/v, pH 5.0). The yeast Pichia fermentans was inoculated at 3×107 cells per gram of initial dry weight. The airstream to supply oxygen also served to supply the precursor. Slow supply was obtained using an isoamyl alcohol solution of 5g l-1 in the bubbling columns and an air stream of 50ml min-1. For fast supply, fermentations were aerated using 10g l-1 and 100ml min-1 for isoamyl alcohol solution and air stream, respectively. It demonstrated the feasibility of isoamyl acetate production in SSF. Moreover, the slow supply of the precursor increased isoamyl acetate production up to 390mg l-1, which is 12.5 times higher than that obtained without precursor (32mg l-1). On the other hand, fast supply caused an evident inhibition of the growth and production capacity of the yeast.

Economic assessment of cellulase production in batch and semi-batch solid-state fermentation processes

AbstractThe vast range of applications for enzymes in the production of biofuels has led to a major increase in market demand in recent years. Cellulase's high cost and poor catalytic efficiency are two key barriers to the industrial usage of lignocellulosic biomass as feedstocks for fuels in biorefineries. In this study, the economic evaluation of cellulase production in solid-state fermentation was done by designing two process routes (batch and semi-batch) to optimize the process. SuperPro Designer Software has been used to create a process model that assessed the economics of fermentation operations while Monte Carlo Software was used to conduct the sensitivity analysis investigation. The impacts of cellulase yield, productivity, aeration rate and specific power input on the unit production cost (UPC) of cellulase enzyme were studied. The batch procedure requires more sterilized air for the aerobic fermentation process than the semi-batch approach, according to the results. In comparison to the batch fermentation process, the semi-batch approach had a payback period of less than 2 years, an internal rate of return of 39.14% and a net present value of $142 089 000. The semi-batch process approach has a higher economic feasibility when compared with the batch fermentation process since it is more certain to attain its base case value of UPC at the maximum. This research was key to developing a process pathway that reduces cellulase production costs in solid-state fermentation while improving market supply for its use in a biorefinery to produce sustainable fuel.

Bio-utilization of agricultural residue banana plant shoot through solid state fermentation for production of inulinase using newly isolated Nothophoma anigozanthi JAM

AbstractThe present research was carried out with the objectives of isolating fungal strains capable of exhibiting inulinase activity from a novel source, then optimizing solid state fermentation for the inulinase production and characterizing crude enzyme. Production of inulinase is first reported in this study with a novel substrate, banana plant shoot powder, using newly isolated fungal strain Nothophoma anigozanthi JAM through solid state fermentation. The fungal strain was isolated from the root soil of a white Jamun (Syzygium cumini) tree. Optimization of the solid state fermentation was carried out by central composite design for determining the interaction and impact of the influential process on inulinase production. A mathematical model was developed based on the statistical analysis and recommended optimal process conditions of 2 g of substrate, 5 mL of moistening media, 5 mL of inoculum volume, and 96 h of fermentation time for enhanced production (2.578 U/gds). Crude inulinase enzyme exhibited an 8.0-fold increase in activity after optimization, in comparison with the activity under unoptimized conditions. The optimum pH (5.0), temperature (60 °C) for the enzyme activity, and Km (0.205 mM) and Vmax (0.333 µM/min) were determined based on the biochemical and inulin hydrolytic properties of the crude inulinase enzyme. The production of inulinase was further validated by using TLC, osazone, and Seliwanoff tests. Hence, the inulinase enzyme produced by Nothophoma anigozanthi JAM can be successfully utilized for the production of edible sugar fructose from non-edible polysaccharide inulin, present in agricultural residues such as banana shoot by solid state fermentation.

Continuous operation of fungal wheel reactor based on solid-state fermentation for the removal of pharmaceutical and personal care products

Wood-rotting fungi and their enzymatic systems represent promising biocatalysts for the removal of pharmaceuticals and personal care products (PPCPs) from wastewater. We designed a fungal wheel reactor (FWR) based on solid-state fermentation (SSF) of Trametes versicolor and a lignocellulosic substrate, which was used as an immobilization carrier for fungal biomass and the sole initial nutrient source for producing fungal oxidative enzymes. Three pharmaceutical and personal care products, acetaminophen, bisphenol A and carbamazepine, were spiked into the synthetic wastewater and the treatment was carried out under non-sterile conditions. Acetaminophen was completely removed from the FWR until laccase was observed. The acetaminophen removal efficiency was retrieved by replacing the fungal wheel with fresh SSF products. Bisphenol A and carbamazepine were removed via enzymatic activity and adsorption. When the fungal wheel was replaced, acetaminophen began to be completely removed, even after laccase depletion. The microbial community analysis indicated that the continuous removal of acetaminophen was mainly due to the high proportion of T. versicolor. The relative abundance of the co-occurring microbial community might be responsible for the divergence in acetaminophen removal between two of fungal wheel-replaced reactors. Overall, FWRs are promising tools for the removal of PPCPs by highly reactive enzymatic mechanisms as well as adsorption on the carrier surface. By replacing SSF and settled microbial communities, FWRs may continuously contribute to bioremediation over a long-term period.

Recent Advances and Technologies in Chitinase Production Under Solid-State Fermentation

ABSTRACT: Our target is to evaluate recent literature on chitinase production from different sources via solid-state fermentation and to analyze several strategies to improve chitinase production via solid-state fermentation. Plant pathogen biocontrol, sequential transformation of chitin into bioactive molecules such as chito-oligosaccharides and N-acetylglucosamine, protoplast synthesis from filamentous fungi, and single-cell protein production are some of the applications for chitinase. Despite their enormous biological importance, chitinases have received little commercial importance due to the smaller percentage of microbes with high efficiencies, the enzymes' decreased activity and consistency, and the cost of production. Solid-state fermentation (SSF) is less expensive, requires fewer vessels, uses less water, requires fewer wastewater treatments, produces a greater product yield, has a lower risk of bacterial contamination, and requires less energy expenditure. Despite its higher productivity and lower cost, the SSF technique is now mostly limited to lab scales. Furthermore, the crude SSF products can be used as an enzyme source for biotransformation. There are many findings on different microorganisms that produce chitinase by SSF. So it is very critical to isolate new organisms for such production. So we assessed the traditional approach to medium optimization, which focuses on changing one factor at a time while leaving the others constant, and statistical optimization techniques such as response surface methodology (RSM), artificial neural networks (ANNs), and genetic algorithms (GA).