scholarly journals The Impact of Substrate–Enzyme Proportion for Efficient Hydrolysis of Hay

Energies ◽  
2019 ◽  
Vol 12 (18) ◽  
pp. 3526 ◽  
Author(s):  
Linda Mezule ◽  
Ieva Berzina ◽  
Martins Strods
Keyword(s):  
White Rot Fungi ◽  
Inhibitory Effect ◽  
White Rot ◽  
Alcohol Production ◽  
Commercial Enzyme ◽  
Loading Rates ◽  
Negative Effect ◽  
Pre Treatment ◽  
The Impact ◽  
Hydrolysis Of

Fuel alcohol production yields can be influenced by lignocellulosic biomass loading. High solid loadings (>20 wt%) are suggested to have the potential to produce more products. However, most often, low substrate loadings (<5% solids, w/w) are used to ensure good wetting and enzyme accessibility, and to minimize any inhibitory effect on the hydrolysis products. Here, we analyzed the effect of substrate loading on the enzymatic hydrolysis of hay with non-commercial enzyme products obtained from white-rot fungi. A significant negative effect on hydrolysis was observed when 10 wt% hay loading was used with the commercial enzyme, however, non-commercial enzyme products from white-rot fungi had no impact on hydrolysis in biomass loading rates from 1 to 10 wt%. Moreover, it was estimated that enzymes extracted from white-rot fungi could be used at a concentration of 0.2 FPU/mL at a biomass loading from 1–10 wt%, resulting in 0.17–0.24 g of released reducing carbohydrates per gram of biomass. Higher concentrations did not result in any significant conversion increase. A mixing impact was only observed in test runs at a substrate loading of 10 wt%. The apparently positive features of the non-commercial enzyme mixes give rise to their future use. The combination and upgrade of existing technologies, e.g., efficient pre-treatment, membrane purification, and concentration and efficient product recovery, should result in even higher conversion yields.

scholarly journals Evaluation of Basidiomycetes Wild Strains Grown in Agro-Industrial Residues for Their Anti-Tyrosinase and Antioxidant Potential and for the Production of Biocatalysts

Fermentation ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 19
Author(s):  
Anastasia Zerva ◽  
Nikolaos Tsafantakis ◽  
Evangelos Topakas
Keyword(s):  
Biomass Conversion ◽  
White Rot Fungi ◽  
Ligninolytic Enzymes ◽  
Inhibitory Effect ◽  
Biologically Active ◽  
White Rot ◽  
Oxidative Enzymes ◽  
Industrial Residues ◽  
Pure Compounds ◽  
Wild Strains

White-rot basidiomycetes are the only microorganisms with the ability to produce both hydrolytic (cellulases and hemicellulases) and oxidative (ligninolytic) enzymes for degrading cellulose/hemicellulose and lignin. In addition, they produce biologically active natural products with important application in cosmetic formulations, either as pure compounds or as standardized extracts. In the present work, three wild strains of Basidiomycetes fungi (Pleurotus citrinopileatus, Abortiporus biennis and Ganoderma resinaceum) from Greek habitats were grown in agro-industrial residues (oil mill wastewater, and corn cob) and evaluated for their anti-tyrosinase and antioxidant activity and for the production of biotechnologically relevant enzymes. P. citrinopileatus showed the most interesting tyrosinase inhibitory activity, while A. biennis showed the highest DPPH(2,2-diphenyl-1-picryl-hydrazyl) scavenging potential. Corn cobs were the most appropriate carbon source for maximizing the inhibitory effect of fungal biomasses on both activities, while the use of oil mill wastewater selectively increased the anti-tyrosinase potential of P. citrinopileatus culture filtrate. All strains were found to be preferential lignin degraders, similarly to most white-rot fungi. Bioinformatic analyses were performed on the proteome of the strains P. citrinopileatus and A. biennis, focusing on CAZymes with biotechnological relevance, and the results were compared with the enzyme activities of culture supernatants. Overall, all three strains showed strong production of oxidative enzymes for biomass conversion applications.

scholarly journals Biodegradability of Extractives in Sapwood and Heartwood from Scots Pine by Sapstain and White-Rot Fungi

Holzforschung ◽  
1999 ◽  
Vol 53 (3) ◽  
pp. 247-252 ◽  
Author(s):  
M.J. Martínez-Inigo ◽  
P. Immerzeel ◽  
A. Gutierrez ◽  
J.C. del Río ◽  
R. Sierra-Alvarez
Keyword(s):  
Scots Pine ◽  
White Rot Fungi ◽  
Inhibitory Effect ◽  
Resin Acids ◽  
White Rot ◽  
White Rot Fungus ◽  
Fungal Degradation ◽  
Steryl Esters ◽  
Funalia Trogii ◽  
Total Extractives

SummaryThe fungal degradation of lipophilic extractives in sapwood and heartwood from Scots pine (Pinus sylvestris) was studied. In sapwood, the white rot fungi,Bjerkanderasp. andFunalia trogii, removed higher amounts of extractives than the sapstain strains,Ophiostoma ainoaeandCeratocystis allantospora. Triglycerides, long chain fatty acids, steryl esters and waxes in pine sapwood were almost completely degraded by all the fungi. Sterols and resin acids were also extensively degraded by the white rot strains; however, these components were not or only poorly removed by the sapstain fungi. The removal of total extractives by all the fungal strains was higher in sapwood as compared to heartwood. The highly concentrated extractive fraction in pine heartwood mainly consists of resin acids. As observed in sapwood, sapstain were also poorly effective in the degradation of the resin acids present in heartwood. The fungal degradation of heartwood extractives was not only limited by the degradative ability of the various test microorganisms, but also by the inhibitory effect exerted by the extractive fraction. The white rot fungusF. trogiiwas particularly inhibited on heartwood.Bjerkanderasp. showed a higher tolerance to toxic extractives and was the most efficient fungus in degrading extractive constituents in both Scots pine heartwood and sapwood. Therefore,Bjerkanderasp. strain BOS55 should be considered as a potential agent for pitch control in pulp and paper manufacture.

scholarly journals Biological pretreatment of wheat straw: Effect of fungal culturing on enzymatic hydrolysis of carbohydrate polymers

2021 ◽  
Author(s):  
Aleksandar Knežević ◽  
Ivana Đokić ◽  
Tomislav Tosti ◽  
Slađana Popović ◽  
Dušanka Milojković-Opsenica ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Lignin Degradation ◽  
Enzymatic Saccharification ◽  
White Rot Fungi ◽  
Fungal Species ◽  
White Rot ◽  
Irpex Lacteus ◽  
Fungal Pretreatment ◽  
Hydrolysis Of

Abstract The aim of the study was comparative analysis of degradation of wheat straw lignin by white-rot fungi and its implications on the efficiency of enzymatic hydrolysis of holocellulose. Cyclocybe cylindracea, Ganoderma resinaceum, Irpex lacteus, Pleurotus ostreatus and Trametes versicolor were the species studied. Peroxidases were predominantly responsible for lignin degradation even though high laccase activities were detected, except in the case of Irpex lacteus where laccase activity was not detected. Studied fungal species showed various ability to degrade lignin in wheat straw which further affected release of reducing sugars during enzymatic saccharification. The highest rate of lignin degradation was noticed in sample pretreated with Irpex lacteus (50.9 ± 4.1%). Among all tested species only Ganoderma resinaceum was suitable lignin degrader with the 2-fold higher hydrolysis yield (51.1 ± 4.7%) than in the control, and could have significant biotechnological application due to lower cellulose loss. A key mechanism of carbohydrate component convertibility enhancement was lignin removal in the biomass. Long time consumption, the low sugar yields and unpredictable fungal response still remain the challenge of the fungal pretreatment process.

scholarly journals The Employment Effect Of Chinese Enterprises Embedded In The Global Environmental Value Chain

2021 ◽  
Author(s):  
Shuhong Wang ◽  
Hanxue Chen ◽  
Kedong Yin
Keyword(s):  
Division Of Labor ◽  
Value Chain ◽  
Business Performance ◽  
Inhibitory Effect ◽  
Employment Effect ◽  
Eastern Region ◽  
Environmental Value ◽  
Global Environmental ◽  
Negative Effect ◽  
The Impact

Abstract The employment effect of enterprises embedded in global value chains has important theoretical value, but existing research has ignored the impact of cross-border pollution transfer on employment under the division of labor system within the value chain. This study constructs a global environmental value chain (GEVC) analysis framework to combine economic and environmental issues and establishes a theoretical model to discuss the impact of the degree of enterprise embeddedness in the GEVC on employment. Using 2000–2006 data from the China Industry Business Performance and China Customs databases, the study finds that an increase in the degree of enterprise embeddedness has a significant inhibitory effect on employment, especially for female laborers, lower-skilled laborers, state-owned enterprises, private enterprises, and enterprises in the eastern region. The research also shows that the cost increase effect enhances the negative effect of increased GEVC embeddedness on employment, while the innovation promotion effect and the foreign direct investment effect serve to mitigate the negative effect. The results provide a reference for developing countries seeking to effectively protect people's livelihood and employment while achieving a leap in the division of labor along the green value chain.

scholarly journals Impact of Regional Environmental Regulations on Taiwanese Investment in Mainland China

2021 ◽  
Vol 13 (8) ◽  
pp. 4134
Author(s):  
Fang Yang ◽  
Qinfan Gan
Keyword(s):  
Local Governments ◽  
Regional Differences ◽  
Environmental Regulations ◽  
Mainland China ◽  
Estimation Method ◽  
Inhibitory Effect ◽  
Environmental Standards ◽  
Investment Volume ◽  
Negative Effect ◽  
The Impact

Based on the perspective of regional differences and decentralization, this article investigated the impact of environmental regulations on Taiwanese investment in mainland China from theoretical and empirical perspectives, and analyzed whether local governments are competing to lower environmental standards to attract Taiwanese investment so as to maintain their comparative advantages. This paper constructed a theoretical model through a two-stage game model. With the panel data of each province in Mainland China from 2006 to 2016, the theoretical propositions were empirically tested through the system GMM estimation method. The results show that the environmental regulation policies adopted by the local governments in the mainland have a significant inhibitory effect on the investment volume of Taiwan-funded enterprises, and the interaction between environmental regulations and local tax burden levels also has a negative effect on Taiwanese investment. Local governments have the motive to reduce environmental regulations to attract investment.

scholarly journals Population Ageing, Financial Deepening and Economic Growth: Evidence from China

2018 ◽  
Vol 10 (12) ◽  
pp. 4627 ◽  
Author(s):  
Shangmei Zhao ◽  
Jiang He ◽  
Haijun Yang
Keyword(s):  
Economic Growth ◽  
Positive Impact ◽  
Threshold Level ◽  
Inhibitory Effect ◽  
Population Ageing ◽  
Marginal Effect ◽  
Financial Deepening ◽  
Dynamic Panel ◽  
Negative Effect ◽  
The Impact

Using a panel of 31 Chinese provinces from 2000 to 2016, we investigated the impact of population ageing and financial deepening on economic growth. Based on the dynamic panel system GMM estimators, the empirical results address that both population ageing and financial deepening have a significantly positive impact on economic growth, while the interactions between them have a significantly negative effect on economic growth. From the perspective of total marginal effect, we also find that population ageing does contribute to economic growth but only when financial deepening is less than a threshold level; however, on the whole, financial deepening has an inhibitory effect on economic growth which increases with population ageing.

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