Production of Extracellular Laccase fromBacillus subtilisMTCC 2414 Using Agroresidues as a Potential Substrate

Laccases are the model enzymes for multicopper oxidases and participate in several applications such as bioremediation, biopulping, textile, and food industries. Laccase producing bacterium,Bacillus subtilisMTCC 2414, was subjected to optimization by conventional techniques and was partially purified using ammonium salt precipitation method. The agroresidue substrates used for higher yield of laccase were rice bran and wheat bran. Maximum production was achieved at temperature 30°C (270 ± 2.78 U/mL), pH 7.0 (345 ± 3.14 U/mL), and 96 h (267 ± 2.64 U/mL) of incubation. The carbon and nitrogen sources resulted in high enzyme yield at 3% sucrose (275 ± 3.11 U/mL) and 3% peptone (352.2 ± 4.32 U/mL) for rice bran and 3% sucrose (247.4 ± 3.51 U/mL) and 3% peptone (328 ± 3.33 U/mL) for wheat bran, respectively. The molecular weights of partially purified laccase were 52 kDa for rice bran and 55 kDa for wheat bran. The laccase exhibited optimal activity at 70°C (260.3 ± 6.15 U/mL), pH 9.0 (266 ± 4.02 U/mL), and metal ion CuSO4(141.4 ± 6.64) was found to increase the production. This is the first report that delivers the higher yield of laccase produced fromB. subtilisMTCC 2414 using agroresidues as a potential substrate.

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Simultaneous hydrolysis and fermentation of defatted rice bran and defatted soybean meal for nisin production with engineered Lactococcus lactis

BioResources ◽

10.15376/biores.15.3.6385-6403 ◽

2020 ◽

Vol 15 (3) ◽

pp. 6385-6403

Author(s):

Jiaheng Liu ◽

Xiangyu He ◽

Yuhui Du ◽

Itsanun Wiwatanaratanabutr ◽

Guangrong Zhao ◽

...

Keyword(s):

Lactococcus Lactis ◽

Rice Bran ◽

Soybean Meal ◽

Nadh Oxidase ◽

Nitrogen Sources ◽

Nisin Production ◽

Carbon And Nitrogen ◽

Defatted Soybean Meal ◽

Commercial Media ◽

Defatted Rice Bran

This work aimed to study the potential of defatted rice bran (DRB) and defatted soybean meal (DSM) as carbon and nitrogen sources for Lactococcus lactis growth and nisin production. First, a maximum nisin yield of 3630 IU/mL was achieved using 40% DRB hydrolysates and 30% DSM hydrolysates, which was 1.13 times greater than that found in commercial media. Second, to simplify the operation and shorten the length of the entire process, the processes of combined hydrolysis of DRB-DSM followed by fermentation, and simultaneous hydrolysis and fermentation of DRB-DSM were developed. Neutral proteinase enhanced the saccharification of DRB by cellulase and α-amylase. Furthermore, the strategy of NADH oxidase expression and hemin addition was innovatively proposed to overcome the oxygen stress in a simultaneous hydrolysis and fermentation process, which could alleviate the lag period following inoculation of L. lactis and result in a 77.3% increase in nisin titer.

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Carbon and Nitrogen Sources Effect on Pectinase Synthesis by Aspergillus niger Under Submerged Fermentation

Biosciences Biotechnology Research Asia ◽

10.13005/bbra/2906 ◽

2021 ◽

Vol 18 (1) ◽

pp. 185-195

Author(s):

Gousiya Begum ◽

Srinivas Munjam

Keyword(s):

Wheat Bran ◽

Submerged Fermentation ◽

Enzyme Production ◽

Paper Industry ◽

Nitrogen Sources ◽

Carbon And Nitrogen Sources ◽

Carbon And Nitrogen ◽

Maximum Production ◽

Fungal Strains ◽

Enhanced Production

Pectinases are the commercial enzymes that are abundantly employed in various industries like fruit juice industries for clarification, wine indutsry and paper industry for bleaching up pulp. The present work was done on culture conditions optimization for production of pectinases under submerged fermentation using wheat bran as a substrate. Fungal strains were isolated from vegetable waste dump yard soils of Warangal district of Telangana state and screened for their activity on pectin agar medium. Among 30 isolates, two fungal strains showed good activity and identified them as A. niger and A. flavus. The effects of the different carbon and nitrogen sources on pectinases viz. exo-PG, endo-PG, endo-PL and PME by A. niger with 1% wheat bran was carried out in submerged fermentation. These studies revealed that carbon and nitrogen sources have shown considerable influence on enzyme production. Among all the carbon sources tried, sucrose at 1% was shown to be efficient carbon source for all four types of pectinases under investigation. For endo-PG, endo-PL and PME maximum enzyme production were recorded on 8th day of incubation period but for exo-PG enhanced production was observed on 12th day. A. niger could not produce PME on 12th day from 2.50% to subsequent concentrations. Among nine different nitrogen sources were screened, maximum pectinase production was recorded in sodium nitrate at 0.2 % for A. niger. Endo-PG, endo-PL and PME maximum production were recorded on 8th day of incubation and for exo-PG maximum production was observed on 12th day. No PME production was observed in A. niger on 12th day.

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Unexpected Link between Metal Ion Deficiency and Autophagy in Aspergillus fumigatus

Eukaryotic Cell ◽

10.1128/ec.00224-07 ◽

2007 ◽

Vol 6 (12) ◽

pp. 2437-2447 ◽

Cited By ~ 71

Author(s):

Daryl L. Richie ◽

Kevin K. Fuller ◽

Jarrod Fortwendel ◽

Michael D. Miley ◽

Jason W. McCarthy ◽

...

Keyword(s):

Metal Ions ◽

Aspergillus Fumigatus ◽

Stress Responses ◽

Metal Ion ◽

Nitrogen Sources ◽

Hyphal Growth ◽

Wild Type ◽

Serine Threonine Kinase ◽

Gene Encoding ◽

Carbon And Nitrogen

ABSTRACT Autophagy is the major cellular pathway for bulk degradation of cytosolic material and is required to maintain viability under starvation conditions. To determine the contribution of autophagy to starvation stress responses in the filamentous fungus Aspergillus fumigatus, we disrupted the A. fumigatus atg1 gene, encoding a serine/threonine kinase required for autophagy. The ΔAfatg1 mutant showed abnormal conidiophore development and reduced conidiation, but the defect could be bypassed by increasing the nitrogen content of the medium. When transferred to starvation medium, wild-type hyphae were able to undergo a limited amount of growth, resulting in radial expansion of the colony. In contrast, the ΔAfatg1 mutant was unable to grow under these conditions. However, supplementation of the medium with metal ions rescued the ability of the ΔAfatg1 mutant to grow in the absence of a carbon or nitrogen source. Depleting the medium of cations by using EDTA was sufficient to induce autophagy in wild-type A. fumigatus, even in the presence of abundant carbon and nitrogen, and the ΔAfatg1 mutant was severely growth impaired under these conditions. These findings establish a role for autophagy in the recycling of internal nitrogen sources to support conidiophore development and suggest that autophagy also contributes to the recycling of essential metal ions to sustain hyphal growth when exogenous nutrients are scarce.

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Production, purification and characterization of thermostable alpha amylase from Bacillus subtilis Y25 isolated from decaying yam (Dioscorea rotundata) tuber

Notulae Scientia Biologicae ◽

10.15835/nsb12110521 ◽

2020 ◽

Vol 12 (1) ◽

pp. 154-171

Author(s):

Oluwatoyin M. ALADEJANA ◽

Olaoluwa OYEDEJI ◽

Olumide OMOBOYE ◽

Mufutau BAKARE

Keyword(s):

Bacillus Subtilis ◽

Metal Ion ◽

Specific Activity ◽

Nitrogen Sources ◽

16S Rrna Gene Sequencing ◽

Exchange Chromatography ◽

Rrna Gene ◽

Carbon And Nitrogen Sources ◽

Carbon And Nitrogen ◽

Amylase Production

Amylases have wide biotechnological potentials for applications in various industries. An α-amylase-producing bacterium was isolated from deteriorating yam tubers. Molecular characterization using the 16S rRNA gene sequencing was used to confirm the identity of the bacterium as Bacillus subtilis Y25. The effect of some cultural and nutritional factors such as pH, temperature, carbon and nitrogen sources on α-amylase production from the bacterium was determined. Maximum α-amylase production was observed using starch and peptone as carbon and nitrogen sources, respectively, with an initial medium pH of 8.0 and incubation at 45 °C for 36 h. The enzyme was purified by ion exchange chromatography on CM Sepharose CL-6B. The kinetic parameters Km and Vmax of the enzyme, as well as the effect of pH, temperature, metal ions and ethylenediaminetetra acetic acid (EDTA) on the activity of the purified enzyme were studied. The specific activity of the partially purified enzyme was determined to be 15.21 Units/mg protein with a purification fold of 3.80. The molecular weight of the purified enzyme was estimated to be 58.0 kDa. The Vmax and Km values obtained with soluble starch for Bacillus subtilis Y25 α-amylase were 314.10 ± 23.30 Units/mg protein and 53.98 ± 12.03 mg/ml, respectively. The enzyme exhibited optimum activity at a temperature of 60 °C and pH 8.0. The metal ion Ca2+ had no effect on the enzyme at 20 mM concentration, whereas Na+ and Mg2+, as well as EDTA inhibited the enzyme at the same concentration. The characteristics of the α-amylase from Bacillus subtilis Y25 revealed it to be a thermostable and an alkaline metalloenzyme with potential for applications in the detergent and saccharification industries.

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Biocatalyst: Cellulase Production in Solid State Fermentation (SSF) Using Rice Bran as Substrate

Biointerface Research in Applied Chemistry ◽

10.33263/briac111.76897699 ◽

2020 ◽

Vol 11 (1) ◽

pp. 7689-7699

Keyword(s):

Rice Bran ◽

Nitrogen Sources ◽

Cellulase Production ◽

Culture Conditions ◽

Carbon And Nitrogen Sources ◽

Carbon And Nitrogen ◽

Glucose Carbon ◽

Biological Transformation ◽

Fermentation Period ◽

Filter Paper Assay

The study was aimed to analyze the biological transformation of cellulose in rice bran by Aspergillus flavus SB04 in SSF for 28 days. The culture conditions such as pH, temperature, moisture content were optimized for the effective production of the enzyme in SSF. Effect of carbon and nitrogen sources on cellulase production was further estimated in SMF and were quantified for 24hrs intervals for 7 days Maximum cellulase production for rice bran was observed to be high in glucose (carbon source) and yeast extract (nitrogen source) at initial moisture 75ml, pH 6, temperature 33°C and fermentation period was 14th day that was optimized using response surface methodology. The enzyme production was analyzed individually by dinitrosalicylic acid (DNS) method, Lowry protein estimation, and filter paper assay. The lignocellulosic degradation was observed and confirmed by FTIR and SEM. The degradation of cellulose periodically increases after 7 days, which influences the yield of cellulase enzyme.

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Wheat Bran Hydrolysate Culture Medium Design for Talaromyces Purpureogenus CFRM02 Pigment Production and Colour Characteristics

10.21203/rs.3.rs-840095/v1 ◽

2021 ◽

Author(s):

Sujit Das ◽

Saritha Gopal Pandit ◽

Mohan Dhale

Keyword(s):

Wheat Bran ◽

Carbon Sources ◽

Nitrogen Sources ◽

Pigment Production ◽

Xylose Metabolism ◽

Carbon And Nitrogen ◽

Medium Design ◽

The Media ◽

Comparative Results ◽

Cie Lab

Abstract Wheat bran hydrolysate (WBH) in combination with carbon and nitrogen was utilised as substrate for pigment production by Talaromyces purpureogenus CFRM02. Pigment yield was significantly increased (≈ 3 fold: OD units and ≈ 2 fold: a* value) by xylose supplementation with WBH compared to other carbon sources. Whereas 1% xylose supplementation increased pigment production (1.57 ± 0.05 OD Units and 49 ± 1.62 a* value). Pigment yield was low when WBH supplemented with 0.3% nitrogen sources. However significant increase (≈ 2-2.5 fold, OD units and a* value) was observed, when yeast extract (1.2%), nitrate of sodium (1.2%) and potassium (1.6%) were supplemented. Accordingly, 16 WBH media were designed by supplementing carbon and nitrogen. Interestingly the pigment production was significantly increased (1.59 OD units and 32 a* value) in the medium supplemented with 4% carbon and 0.9–1.2% nitrogen. T. purpureogenus CFRM02 was able to co-utilize xylose, fructose and glucose in WBH medium. The CIE Lab values indicated that, pigment characteristics differed significantly among the media. Apparently, T. purpureogenus CFRM02 possess alternative gene(s) or pathway(s) for xylose metabolism and channelled towards pigment biosynthesis. Comparative results revealed that, 1% xylose supplementation to WBH makes the fermentation process economically competitive for pigment production.

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THE STUDY OF ETHANOL PRODUCTION BY NEW STRAIN OF YEASTS "HANSENIASPORA OPUNTIAE MK 460485", INVESTIGATION OF ITS ETHANOL PRODUCTION IN PRESENCE OF DIFFERENT CARBON AND NITROGEN SOURCES, AND OPTIMAL CONDITIONS

Journal of Critical Reviews ◽

10.31838/jcr.07.04.94 ◽

2020 ◽

Vol 7 (04) ◽

Keyword(s):

Ethanol Production ◽

Nitrogen Sources ◽

Optimal Conditions ◽

Carbon And Nitrogen Sources ◽

Carbon And Nitrogen

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A highly thermotolerant laccase produced by Cerrena unicolor strain CGMCC 5.1011 for complete and stable malachite green decolorization

AMB Express ◽

10.1186/s13568-020-01118-z ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Yanhua Yao ◽

Guimei Zhou ◽

Yonghui Lin ◽

Xinqi Xu ◽

Jie Yang

Keyword(s):

Malachite Green ◽

Fermentation Broth ◽

Nitrogen Sources ◽

Life Time ◽

Industrial Applications ◽

Dynamics Simulation ◽

Carbon And Nitrogen ◽

Cdna Sequences ◽

Cerrena Unicolor ◽

Future Work

Abstract Laccases are a class of multi-copper oxidases with important industrial values. A thermotolerant laccase produced by a basidiomycete fungal strain Cerrena unicolor CGMCC 5.1011 was studied. With glycerin and peptone as the carbon and nitrogen sources, respectively, a maximal laccase activity of 121.7 U/mL was attained after cultivation in the shaking flask for 15 days. Transcriptomics analysis revealed an expressed laccase gene family of 12 members in C. unicolor strain CGMCC 5.1011, and the gene and cDNA sequences were cloned. A glycosylated laccase was purified from the fermentation broth of Cerrena unicolor CGMCC 5.1011 and corresponded to Lac2 based on MALDI-TOF MS/MS identification. Lac2 was stable at pH 5.0 and above, and was resistant to organic solvents. Lac2 displayed remarkable thermostability, with half-life time of 1.67 h at 70 ºC. Consistently, Lac2 was able to completely decolorize malachite green (MG) at high temperatures, whereas Lac7 from Cerrena sp. HYB07 resulted in accumulation of colored MG transformation intermediates. Molecular dynamics simulation of Lac2 was conducted, and possible mechanisms underlying Lac2 thermostability were discussed. The robustness of C. unicolor CGMCC 5.1011 laccase would not only be useful for industrial applications, but also provide a template for future work to develop thermostable laccases.

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