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1.
Bioprocess Biosyst Eng ; 45(8): 1281-1295, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35750867

RESUMO

A systematic evaluation of microorganism's potential towards biosynthesis of cellulases from inexpensive lignocellulosic feedstock through appropriate kinetic modelling facilitates understanding, optimization and designing of an effective industrial cellulase enzyme production process. The present study aims to optimize a submerged fungal cultivation strategy for cellulase production from abundantly available newspaper wastes (NPW). A combined pretreatment strategy consisting diluted, 1% (v v-1) H2SO4 followed by 2% (w v-1) NaOH treatment was highly effective to convert newspaper waste to an effective cellulose-enriched inducer for the production of cellulase. In addition, the composition of the most influential nutrient components like peptone and lactose was optimized with the help of response surface methodology for enhanced cellulase production with maximum activity levels. Maximum cellulase production of 8.64 g L-1 with 7.82 FPU mL-1 total activity levels was achieved from optimized composition of pretreated NPW 3.29% (w v-1), lactose 2.94% (w v-1) and peptone 1.53% (w v-1). To analyse intrinsic inhibition effect of the substrate concentration on cellulase production, modified Luedeking-Piret model simulated experiments were further conducted with 1.5% (w/v), 3.29% (w/v) and 4% (w/v) NPW concentrations. The developed kinetic model perfectly captured the trends of biomass production, substrate consumption and adsorption characteristic of cellulase enzyme on its activity during production. The rate constant for cellulase synthesis was evaluated to be increased to 0.040 IU g-1 h -1 at 3.29% (w v-1) of NPW concentration; however, it was further reduced to 0.024 IU g-1 h -1 at higher NPW concentration of 4% (w v-1).


Assuntos
Celulase , Celulases , Biomassa , Celulase/química , Fermentação , Lactose , Peptonas
2.
Physiol Plant ; 168(2): 301-317, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31264712

RESUMO

In the recent times, plants are facing certain types of environmental stresses, which give rise to formation of reactive oxygen species (ROS) such as hydroxyl radicals, hydrogen peroxides, superoxide anions and so on. These are required by the plants at low concentrations for signal transduction and at high concentrations, they repress plant root growth. Apart from the ROS activities, hydrogen sulfide (H2 S) and nitric oxide (NO) have major contributions in regulating growth and developmental processes in plants, as they also play key roles as signaling molecules and act as chief plant immune defense mechanisms against various biotic as well as abiotic stresses. H2 S and NO are the two pivotal gaseous messengers involved in growth, germination and improved tolerance in plants under stressed and non-stress conditions. H2 S and NO mediate cell signaling in plants as a response to several abiotic stresses like temperature, heavy metal exposure, water and salinity. They alter gene expression levels to induce the synthesis of antioxidant enzymes, osmolytes and also trigger their interactions with each other. However, research has been limited to only cross adaptations and signal transductions. Understanding the change and mechanism of H2 S and NO mediated cell signaling will broaden our knowledge on the various biochemical changes that occur in plant cells related to different stresses. A clear understanding of these molecules in various environmental stresses would help to confer biotechnological applications to protect plants against abiotic stresses and to improve crop productivity.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Óxido Nítrico/fisiologia , Fenômenos Fisiológicos Vegetais , Transdução de Sinais , Estresse Fisiológico , Plantas , Espécies Reativas de Oxigênio
3.
J Biochem Mol Toxicol ; 34(10): e22556, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32627257

RESUMO

Myocardial infarction (MI) is a life-threatening disease. In this study, we examined the anti-mitochondrial damaging effects of sinapic acid (SA) in isoproterenol (ISO)-induced myocardial infarcted rats. Myocardial infarcted rats were prepared by injecting ISO (100 mg/kg body weight) on the 9th and 10th day. Rats were pretreated and cotreated with SA (12 mg/kg body weight) orally, daily for 10 days. A considerable increase in serum lactate dehydrogenase, creatine kinase, myoglobin, and cardiac troponin-T was noticed in the ISO-induced rats. ISO also significantly amplified lipid peroxidation and calcium ions, and depleted the antioxidant system and mitochondrial enzymes in rat's heart mitochondria. SA treatment improved the distorted above- mentioned biochemical parameters in ISO-treated rats with its anti-mitochondrial damaging effects. This ultrastructural study on heart mitochondria and in vitro studies also confirmed the effects of SA. The current findings are suggestive of SA's cardioprotective effects.


Assuntos
Agonistas Adrenérgicos beta/toxicidade , Cardiotônicos/farmacologia , Ácidos Cumáricos/farmacologia , Isoproterenol/toxicidade , Mitocôndrias Cardíacas/efeitos dos fármacos , Infarto do Miocárdio/patologia , Animais , Biomarcadores/sangue , Masculino , Mitocôndrias Cardíacas/ultraestrutura , Infarto do Miocárdio/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
4.
Int J Biol Macromol ; 246: 125589, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37385322

RESUMO

The increasing demand for biopolymers across diverse fields, such as food, medicine, cosmetics, and environmental applications, has prompted researchers to explore novel molecules with enhanced functionalities that meet these demands. In this study, a thermophilic strain of Bacillus licheniformis was employed to produce a unique polyamino acid. This thermophilic isolate exhibited rapid growth at 50 °C in a sucrose mineral salts medium, resulting in a biopolymer concentration of 7.4 g/L. Interestingly, the biopolymer produced at different temperatures exhibited varying glass-transition temperatures (ranging from 87.86 °C to 104.11 °C) and viscosities (7.5 cP to 16.3 cP), suggesting that the fermentation temperature significantly influenced the degree of polymerization. Furthermore, the biopolymer was characterized using various techniques, including Thin Layer Chromatography (TLC), Fourier Transform Infrared (FTIR) spectroscopy, Liquid Chromatography-Electrospray Ionization-Mass Spectroscopy (LC-ESI MS), Nuclear Magnetic Resonance (NMR), and Differential Scanning Calorimetry-Thermogravimetric Analysis (DSC-TGA). The results revealed that the obtained biopolymer was a poly amino acid, with poly-γ-glutamic acid as the major monomeric component in the polymer backbone with a few appendages of aspartic acid residues in its side chain. Finally, the biopolymer demonstrated significant coagulation potential for water treatment applications, as evidenced by coagulation studies conducted under varying pH conditions using kaolin-clay as a model precipitant.

5.
Environ Sci Pollut Res Int ; 30(13): 36710-36727, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36562976

RESUMO

The application of on-site produced cellulolytic enzymes in place of commercial enzymes towards hydrolytic preparations of reducing sugars using inexpensive lignocellulosic wastes is considered the most efficient strategy to accomplish a cost-effective biofuel production process. Along with improved production, intrinsic and systematic performance evaluation of the produced enzyme during the hydrolysis process through kinetic intervention remains a crucial requirement for achieving the improved performance of the process. With this motivation, the present study primarily deals with the nutritionally optimized production strategy of cellulases from rice straw (RS) waste using Trichoderma reesei (MTCC 164). The highest cellulase production was obtained 8.09 ± 0.32 g/l in batch mode at optimized combinations of 3.5% (w/v) RS inducer, 3.0% (w/v) lactose, and 1.5% (w/v) peptone. Production was further improved through pH-regulated (pH 5.5 to 6.5) fed-batch fermentations. The enzyme produced at pH 6 was considered for hydrolysis studies at 4 to 10% (w/w) solid loading due to reasonable exoglucanase, endoglucanase, and maximum ß-glucosidase activity levels of 9.3 U/ml, 3.87 U/ml, and 2.65 U/ml respectively. Multi-reaction systematic kinetic modeling was implemented to evaluate enzyme performance during hydrolysis, and the values of inhibitory kinetic parameters (K2r = 7.1 < K1r = 18.5 < K3r = 276.6) suggested that sequential conversion of cellulose to glucose by existing enzyme components was more dominant over direct conversion.


Assuntos
Celulase , Celulases , Oryza , Oryza/metabolismo , Hidrólise , Celulose/metabolismo , Fermentação
6.
Bioresour Technol ; 365: 128180, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36283673

RESUMO

Practically, high-yield conversion of biomass into value-added products at low cost is a primary goal for any lignocellulosic refinery. In the industrial context, the limitation in the practical adaptation of the conventional techniques practically involves multiple reactors for the conversion of biomass to bioproducts. Therefore, the present manuscript critically reviewed the advancements in one-pot reaction systems with a major focus on the scientific production of value-added products from lignocellulosic biomass. In view of that, the novelty of one-pot reactions is shown during the fractionation of biomass into their individual constituents. The importance of the direct conversion of cellulose and lignin into a range of valuable products including organic acids and platform chemicals are separately discussed. Finally, the article is concluded with the opportunities, existing troubles, and possible solutions to overcome the challenges in lignocellulosic biorefinery. This article will assist the readers to identify the economic-friendly-one-pot conversion of lignocellulosic biomass.


Assuntos
Celulose , Lignina , Biomassa , Compostos Orgânicos , Biocombustíveis
7.
Environ Sci Pollut Res Int ; 29(42): 62785-62806, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35802333

RESUMO

Strategic valorization of readily available sugarcane bagasse (SB) is very important for waste management and sustainable biorefinery. Conventional SB pretreatment methods are ineffective to meet the requirement for industrial adaptation. Several past studies have highlighted different pretreatment procedures which are lacking environmentally benign characteristics and effective SB bioconversion. This article provides an in-depth review of a variety of environmentally acceptable thermochemical and biological pretreatment techniques for SB. Advancements in the conversion processes such as pyrolysis, liquefaction, gasification, cogeneration, lignin conversion, and cellulose conversion via fermentation processes are critically reviewed for the formation of an extensive array of industrially relevant products such as biofuels, bioelectricity, bioplastics, bio adsorbents, and organic acids. This article would provide comprehensive insights into several crucial aspects of thermochemical and biological conversion processes, including systematic perceptions and scientific developments for value-added products from SB valorization. Moreover, it would lead to determining efficient pretreatment and/or conversion processes for sustainable development of industrial-scale sugarcane-based biorefinery.


Assuntos
Biocombustíveis , Saccharum , Biomassa , Celulose , Lignina
8.
Nat Prod Bioprospect ; 10(6): 431-443, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33118125

RESUMO

Diabetes mellitus is referred as common metabolic abnormalities characterized as hyperglycemia, mainly caused due to insufficient production of insulin at cellular level or/and defects in insulin action. Such an endocrine disorder is responsible for serious health problems and its worldwide prevalence is rapidly increasing. Common management of diabetes by oral administration of drugs without creating any side effects is still considered a challenging task and increasing cost of conventional medicine in developing countries is another matter of concern. To address these issues, traditional preparations of herbal plant extracts in the form of medicines already gained immense attention. Swertia chirayita is one among such plants which is known for its hypoglycemic potential. Numerous chemical constituents with promising pharmacological properties have been identified from such plant extracts but still, such compounds have not been well characterized, specifically against human application. Hence, more research efforts are necessitated to understand exact mechanism of such compounds and to develop overall safety of such plant formulations. Present review clearly represents antidiabetic properties of Swertia chirayita extract, strategies to be taken to strengthen its safety application on humans and biotechnological interventions that ensure conservation of such endangered species to promote its future application in modern medicine.

9.
3 Biotech ; 8(9): 402, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30221115

RESUMO

Experimental investigations were carried out to develop economic production process of cellulase using coconut mesocarp as an inexpensive lignocellulosic inducer while replacing commercial cellulose. Cellulase production was initially investigated from commercial cellulose in different submerged conditions using Trichoderma reesei (MTCC 164). Maximum enzyme production was achieved 6.3 g/l with activity level 37 FPU/ml in the condition where cellulose to water content ratio was maintained at 5:35 (W/V). To achieve similar maximum production of cellulase from coconut mesocarp, response surface methodology was implemented to optimize most influencing parameters. Most influencing nutritional parameters such as coconut mesocarp, glucose and peptone were optimized in the concentration ranges of 35 g/l, 35 g/l and 25 g/l, respectively. Selecting optimized parameter values, fermentations were conducted inside the fermenter with 2 L operating volume to ensure high concentration and activity profiles of enzyme. Enzyme concentration was achieved 7.20 g/l after 96 h of batch fermentation with specific activity levels of 42 FPU/ ml and CMCase 75 U/ml. Enzyme concentration was further improved to 9.58 g/l with activity levels of 54 FPU/ml and CMCase 93 U/ml by adopting sequential feeding of coconut mesocarp in fed-batch fermentation mode. The presence of pure cellulase in the sample was confirmed by FTIR analysis.

10.
3 Biotech ; 7(5): 310, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28955607

RESUMO

Experimental investigations were carried out for Cupriavidus necator (MTCC 1472)-based improved production of poly-3 hydroxy butyrate (PHB) through induced nitrogen limiting fed-batch cultivation strategies. Initially Plackett-Burman design and response surface methodology were implemented to optimize most influencing process parameters. With optimized process parameter values, continuous feeding strategies ware applied in a 5-l fermenter with table sugar concentration of 100 g/l, nitrogen concentration of 0.12 g/l for fed-batch fermentation with varying dilution rates of 0.02 and 0.046 1/h. To get enriched production of PHB, concentration of the sugar was further increased to 150 and 200 g/l in feeding. Maximum concentrations of PHB achieved were 22.35 and 23.07 g/l at those dilution rates when sugar concentration maintains at 200 g/l in feeding. At maximum concentration of PHB (23.07 g/l), productivity of 0.58 g/l h was achieved with maximum PHB accumulation efficiency up to 64% of the dry weight of biomass. High purity of PHB, close to medical grade was achieved after surfactant hypochlorite extraction method, and it was further confirmed by SEM, EDX, and XRD studies.

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