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1.
Bioresour Technol ; 363: 127893, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36067897

RESUMO

In this study, Caulerpa racemosa oil was used to produce biodiesel by recombinant Pichia pastoris displaying bound (rPp-BL) and secretory lipase (rPp-SL). Collected algae was pre-treated using ultrasonication, microwave and solvent extraction. Defatted C. racemosa was subjected to dilute acid treatment to obtain algal biomass hydrolysate. Both rPp-BL and rPp-SL were cultivated in algal biomass hydrolysate and glycerol. Surfactant treatment was performed on rPp-BL. Screening and optimization of variables were performed for biodiesel production using Plackett Burman design and central composite design, respectively. About 10.64 % (w/w) of algal oil was extracted from C. racemosa. Both rPp-BL and rPp-SL effectively utilized C. racemosa biomass hydrolysate and glycerol. rPp-SL combined with triton X (1.0 % w/v) treated rPp-BL for 3 min improved lipase activity. Methanol to oil ratio, combined whole cell biocatalyst and temperature were significant factors. Under optimum conditions, biodiesel yield reached about 93.64 % after 30 h using developed whole cell biocatalyst.


Assuntos
Biocombustíveis , Caulerpa , Candida/metabolismo , Caulerpa/metabolismo , Glicerol/metabolismo , Lipase/metabolismo , Metanol/metabolismo , Metanol/farmacologia , Pichia/genética , Pichia/metabolismo , Saccharomycetales , Solventes/metabolismo , Tensoativos/metabolismo
2.
Bioresour Technol ; 351: 126956, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35272039

RESUMO

In the present work, Aspergillus niger was employed to produce commercially valuable malic acid from crude glycerol derived from waste cooking oil. Crude glycerol dosage, yeast extract dosage and initial pH were the influencing factors playing a significant role in the malic acid synthesis. The optimal condition for malic acid biosynthesis was studied by using response surface methodology. Further the feasibility analysis for biosynthesis of malic acid from crude glycerol was studied using the laboratory scale optimized data, with this experimentally optimized data, plant was simulated using SuperPro Designer (v10). The cost involved for malic acid synthesis per unit volume was likely expected to be $0.43/kg of malic acid using reactive extraction method. Thus, process optimization combined with techno-economical analysis of malic acid production could be beneficial.


Assuntos
Glicerol , Malatos , Aspergillus niger , Culinária
3.
Sci Total Environ ; 709: 136206, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-31905567

RESUMO

Crude glycerol, one of the ever-growing by-product of biodiesel industry and is receiving the closest review in recent times because direct disposal of crude glycerol may emerge ecological issues. The renewability, bioavailability and typical structure of glycerol, therefore, discover conceivable application in serving the role of carbon and energy source for microbial biosynthesis of high value products. This conceivable arrangement could find exploitation of crude glycerol as a renewable building block for bio-refineries as it is economically as well as environmentally profitable. In this review, we summarize the uptake and catabolism of crude glycerol by different wild and recombinant microorganism. The chemical and biochemical transformation of crude glycerol into high esteem malic acid by various microbial pathways is also additionally discussed. An extensive investigation in the synthesis of high-value malic acid production from various feed stock which finds applications in cosmeceutical and chemical industries, food and beverages, and to some extent in the field of medical science is also likewise studied. Finally, the open doors for unrefined crude glycerol in serving as a promising abundant energy source for malic acid production in near future have been highlighted.


Assuntos
Biocombustíveis , Fermentação , Glicerol , Malatos
4.
Bioresour Technol ; 293: 122060, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31514122

RESUMO

In the present study, Kluyveromyces marxianus was utilized to study the batch fermentation kinetics of biomass production, substrate utilization and bioethanol production from woody stem Prosopis juliflora. The pre-treated substrate was subjected to Simultaneous Saccharification and Fermentation (SSF) under optimised conditions of pH (4.9), temperature (41 °C), substrate concentration 5% (w/v), inoculum concentration 3% (v/v) and the maximum concentration of bioethanol was found to be 21.45 g/l. The experimental data thus obtained from cell growth, substrate utilization and product formation are employed in the determination of kinetic parameters. Biological models such as Logistic model, Hinshelwood model were used for microbial growth and substrate utilization kinetics respectively. In case of product kinetics, Leudking-Piret plot, Gompertz model and Modified Gompertz model were utilised. Based on these models, kinetic parameters like maximum specific growth rate (µm), saturation constant (Ks), growth associated (α), non-growth associated (ß) and yield coefficients (YX/S, YP/S) were estimated.


Assuntos
Kluyveromyces , Prosopis , Etanol , Fermentação , Cinética
5.
Bioresour Technol ; 286: 121402, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078981

RESUMO

This study investigated the biohydrogen production from brewery effluents using free and immobilized co-culture of mutated Rhodobacter M 19 and Enterobacter aerogenes obtained from random mutagenesis with ultra violet (UV) and ethidium bromide (EtBr) treatment. The best mutant for biohydrogen production was screened based on the sugar utilization efficiency. Maximum hydrogen production of 87% was achieved with immobilized EtBr mutated co-culture. The mutant immobilized strains showed around 30% enhanced hydrogen production than wild strains at pH 6.9. Gompertz and Richard's model were used to fit the augmenting biohydrogen production and Logistics equation determines the fitness of biomass growth data. The maximal biomass concentration of co-cultures strains was 3.145 g/L with carrying capacity coefficient 0.137 h-1. Gompertz model showed the best fit with minimal error in predicting the biohydrogen potential.


Assuntos
Enterobacter aerogenes , Técnicas de Cocultura , Fermentação , Hidrogênio , Rhodobacter
6.
Bioresour Technol ; 251: 264-267, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29288953

RESUMO

In the present investigation, crude glycerol derived from transesterification process was utilized to produce the commercially-valuable malic acid. A combined resistant on methanol and malic acid strain of Aspergillus niger MTCC 281 mutant was generated in solid medium containing methanol (1-5%) and malic acid (40-80 g/L) by the adaptation process for 22 weeks. The ability of induced Aspergillus niger MTCC 281 mutant to utilize crude glycerol and pure glycerol to produce malic acid was studied. The yield of malic acid was increased with 4.45 folds compared with that of parent strain from crude glycerol. The highest concentration of malic acid from crude glycerol by using beneficial mutant was found to be 77.38 ±â€¯0.51 g/L after 192 h at 25 °C. This present study specified that crude glycerol by-product from biodiesel production could be used for producing high amount of malic acid without any pretreatment.


Assuntos
Aspergillus niger , Glicerol , Malatos , Biocombustíveis , Fermentação
7.
Bioresour Technol ; 239: 538-541, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28549810

RESUMO

In the present study Trichoderma reesei, a wood isolate can yield high biomass quantities up to 30g/L, yielding 32.4% of lipids of dry cell weight (DCW). Biodiesel production from Trichoderma reesei involved simple unit operations like filtration and ultrasonication, yet giving good lipid yield with desirable bio-diesel properties. Optimization of ultrasonication conditions was done to ensure maximum lipid extraction. SEM analysis of ultrasonicated samples showed distinct breakage of fungal hyphae. The lipids were found to contain 49.7% saturated fatty acids. Transesterification using chemical and biological catalysts were compared and 96.09% efficiency was observed for lipase-catalyzed transesterification. The bio-diesel properties satisfied ASTM and EN specifications with cetane number: 53.1, iodine value: 63.34g, saponification value: 235.07mg KOH/g, cold flow plugging point: 9.13°C.


Assuntos
Biocombustíveis , Trichoderma , Madeira , Ácidos Graxos , Lipídeos
8.
Bioresour Technol ; 235: 250-255, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28371762

RESUMO

The aim of the work is to produce d-Tagatose by direct addition of alginate immobilized Lactobacillus plantarum cells to lactose hydrolysed whey permeate. The cells were untreated and immobilized (UIC), permeabilized and immobilized (PIC) and the relative activities were compared with purified l-arabinose isomerase (l-AI) for d-galactose isomerization. Successive lactose hydrolysis by ß-galactosidase from Escherichia coli and d-galactose isomerization using l-AI from Lactobacillus plantarum was performed to investigate the in vivo production of d-tagatose in whey permeate. In whey permeate, maximum conversion of 38% and 33% (w/w) d-galactose isomerization by PIC and UIC has been obtained. 162mg/g and 141mg/g of d-tagatose production was recorded in a 48h reaction time at 50°C, pH 7.0 with 5mM Mn2+ ion concentration in the initial substrate mixture.


Assuntos
Lactobacillus plantarum , Soro do Leite , Aldose-Cetose Isomerases , Galactose/química , Hexoses/química , Concentração de Íons de Hidrogênio , beta-Galactosidase
9.
Crit Rev Food Sci Nutr ; 57(16): 3430-3437, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26745466

RESUMO

D-tagatose is a naturally existing rare monosaccharide having prebiotic properties. Minimal absorption, low metabolizing energy, and unique clinical properties are the characteristics of D-tagatose. D-tagatose gained international attention by matching the purpose of alternate sweeteners that is much needed for the control of diabetes among world population. Recent efforts in understanding tagatose bioconversion have generated essential information regarding its production and application. This article reviews the evolution of D-tagatose as an important rare sugar by appreciable improvements in production results and its significant applications resulted of its unique physical, chemical, biological, and clinical properties thus considering it an appropriate product for requisite improvements in technical viability. Based on current knowledge and technology projections, the commercialization of D-tagatose rare sugar as food additive is close to reality.


Assuntos
Biotecnologia , Hexoses/biossíntese , Microbiologia Industrial , Edulcorantes/metabolismo , Aldose-Cetose Isomerases/metabolismo , Bactérias/enzimologia , Hexoses/química , Humanos , Edulcorantes/química
10.
Bioresour Technol ; 213: 69-78, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26906444

RESUMO

In this investigation, oil extraction was performed in marine macroalgae Gracilaria edulis, Enteromorpha compressa and Ulva lactuca. The algal biomass was characterized by Scanning Electron Microscopy and Fourier Transform-Infra Red Spectroscopy. Six different pre-treatment methods were carried out to evaluate the best method for maximum oil extraction. Optimization of extraction parameters were performed and high oil yield was obtained at temperature 55°C, time 150min, particle size 0.10mm, solvent-to-solid ratio 6:1 and agitation rate 500rpm. After optimization, 9.5%, 12.18% and 10.50 (g/g) of oil extraction yield was achieved from the respective algal biomass. The rate constant for extraction was obtained as first order kinetics, by differential method. Stable intracellular Cal A and Cal B lipase producing recombinant Pichia pastoris was constructed and used as biocatalyst for biodiesel production. Comparative analysis of lipase activity and biodiesel yield was made with immobilized Candida antarctica lipase.


Assuntos
Biocombustíveis , Biotecnologia/métodos , Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Óleos/metabolismo , Pichia/metabolismo , Alga Marinha/metabolismo , Biocatálise , Biocombustíveis/análise , Culinária , Esterificação , Ácidos Graxos/análise , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Ulva/metabolismo , Resíduos
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