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1.
Electron. j. biotechnol ; 51: 79-87, May. 2021. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1343441

RESUMO

BACKGROUND: At present, cellulases are the most important enzymes worldwide, and their demand has been increasing in the industrial sector owing to their notable hydrolysis capability. RESULTS: In the present study, contrary to conventional techniques, three physical parameters were statistically optimized for the production of cellulase by thermophilic fungi by using response surface methodology (RSM). Among all the tested thermophilic strains, the best cellulase producing fungus was identified as Talaromyces thermophilus ­ both morphologically and molecularly through 5.8S/ITS rDNA sequencing. The central composite design (CCD) was used to evaluate the interactive effect of the significant factors. The CCD was applied by considering incubation period, pH, and temperature as the model factors for the present investigation. A second-order quadratic model and response surface method revealed that the independent variables including pH 6, temperature 50 C, and incubation period 72 h significantly influenced the production of cellulases. The analysis of variance (ANOVA) indicated that the established model was significant (P 0.05) and showed the high adequacy of the model. The actual and predicted values of CMCase and FPase activity showed good agreement with each other and also confirmed the validity of the designed model. CONCLUSIONS: We believe the present findings to be the first report on cellulase production by exploiting Kans grass (Saccharum spontaneum) as a substrate through response surface methodology by using thermophilic fungus, Talaromyces thermophilus.


Assuntos
Talaromyces/metabolismo , Celulases/biossíntese , Análise de Variância , Saccharum , Fermentação , Temperatura Alta , Concentração de Íons de Hidrogênio
2.
Biosci. j. (Online) ; 37: e37021, Jan.-Dec. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1359538

RESUMO

Cellulase has myriad applications in various sectors like pharmaceuticals, textile, detergents, animal feed and bioethanol production, etc. The current study focuses on the isolation, screening and optimization of fungal strain through one factor at a time technique for enhanced cellulase production. In current study sixteen different fungal cultures were isolated and the culture which quantitatively exhibits higher titers of cellulase activity was identified both morphologically and molecularly by 18S rDNA and designated as Aspergillus niger ABT11. Different parameters like fermentation medium, volume, temperature, pH and nutritional components were optimized. The highest CMCase and FPase activities was achieved in 100ml of M5 medium in the presence of 1% lactose and sodium nitrate at 30 oC, pH5 after 72 hours. The result revealed A. niger can be a potential candidate for scale up studies.


Assuntos
Aspergillus niger , Celulase , Fermentação
3.
Biosci. j. (Online) ; 37: e37023, Jan.-Dec. 2021. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1359541

RESUMO

This study assessed the potential of termite gut inhabiting bacteria towards bioconversion of cellulosic waste into biofuel. Total seven bacterial isolates from the gut of Heterotermes indicola were isolated. Among all the isolates, HI-1 produced the largest zone upon primary screening. Untreated paper had more cellulose content (73.03%) than acid (0.5%) treated paper that was used as a lignocellulosic substrate for saccharification. Among all the isolates tested, glucose yield (1.08mg/mL) was high for HI-1 isolate. Several factors were considered for optimizing augmented glucose yield (8.57mg/mL) and growth (8.07×108cfu/mL), such as temperature 37°C, pH 4.5, 5% (w/v) substrate concentration, 6 % bacterial inoculum size, agitation 150 rpm with PEG 0.25 % and Ca2+ ions 0.002 g/L. Overall 8-fold increase in glucose yield was achieved. Enzyme activity of HI-1 showed higher endoglucanase 0.29 ± 0.01 (U/mL/min) and exoglucanase 0.15±0.01 (U/mL/min) activity under optimum conditions, mentioned above. temperature 37°C, pH 4.5, substrate concentration 5%, inoculum size 6%, surfactants PEG 0.01%, ions Ca2+(0.002g/L) and agitation (120 rpm). Simultaneous saccharification and fermentation (SSF) of hydrolyzed office paper yielded 5.43mg/mL bioethanol. According to 16S rRNA sequence homology, the bacterial isolate H1 was identified as Alcaligenes faecalis. Bioethanol production from office paper untreated waste proved an effective strategy. Bacteria having natural tendency towards cellulosic waste consumption are promising for bioconversion of cellulosic waste to valuable products.


Assuntos
Isópteros/microbiologia , Alcaligenes faecalis , Bioetanol
4.
Biosci. j. (Online) ; 37: e37022, Jan.-Dec. 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1359872

RESUMO

Thyroid hormones play a significant role in normal human body growth. Abnormalities in thyroid stimulating hormone (TSH) levels can result in pregnancy loss due to miscarriages and intrauterine death (IUD). The objective of the study was to assess the levels of association of thyroid stimulating hormone with miscarriages and IUD. The descriptive study involving 110 samples between 18-40 years of age fulfilling inclusion criteria were sampled for TSH testing (2ml blood) after attaining their written informed consent. The mean age of participants was 29.49±4.26 year. The prevalence of hypothyroidism and hyperthyroidism was 3.64% and 2.73%, respectively. Complications like gestational hypertension, depression and oligomenorrhea were found prevalent in these females. Majority of females were taking high/low iodine than recommended iodine level (150mcg). This work shows that there is a significant association between pregnancy loss and disturbed TSH levels among pregnant females.


Assuntos
Tireotropina , Aborto Espontâneo , Dispositivos Intrauterinos , Gestantes , Hipertireoidismo , Hipotireoidismo
5.
Biosci. j. (Online) ; 35(5): 1552-1559, sept./oct. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1049051

RESUMO

ß-glucosidase has wide spectrum of biotechnological applications in different industries including food, textile, laundry detergents, pulp and paper, pharmaceutical and biofuel industry. The present investigation related to isolation, screening, and process optimization of fungal strain for enhanced production of ß-glucosidase (BGL). For this purpose, different fungal stains were isolated from different sources including soil, fruits, bark of tree as well as from the compost. The screening of fungal strain for BGL production was carried out via submerged fermentation. All the tested strains were identified on the basis of micro and macroscopic features. The fungal strain having greater ability for BGL synthesis among tested ones wasidentified as Aspergillus niger and given the code SBT-15. The process parameter including fermentation media, temperature, pH, rate of fermentation, carbon and nitrogen sources, volume of media were optimized. Five different fermentation media were evaluatedM3medium gave maximum production. The optimal conditions for BGL production was 72 hours of incubation at 40°C, pH 6 and 50 ml fermentation medium. Glucose (1%) and ammonium sulphate(3%) were optimized as best carbon and nitrogen sources, respectively.


A ß-glicosidase possui amplo espectro de aplicações biotecnológicas em diferentes indústrias, incluindo alimentos, têxteis, detergentes para lavanderia, papel e celulose, indústria farmacêutica e de biocombustíveis, etc. A presente investigação relaciona-se ao isolamento e triagem e otimização de processos de cepas fúngicas para produção aumentada de ß- glucosidase (BGL). Para este efeito, diferentes manchas fúngicas foram isoladas a partir de diferentes fontes, incluindo solo, frutos, casca de árvore, bem como a partir do composto. A triagem da linhagem fúngica para produção de BGL foi realizada via fermentaçãosubmersa. Todas as cepas testadas foram identificadas com base em características micro e macroscópicas. A linhagem fúngica com maior capacidade de síntese de BGL entre os testados foi identificada como Aspergillus niger e recebeu o código SBT-15. O parâmetro do processo, incluindo meios de fermentação, temperatura, pH, taxa de fermentação, fontes de carbono e nitrogênio, volume de mídia foram otimizados. Cinco meios de fermentação diferentes foram avaliados. O meio M3 deu a produção máxima. As condições ótimas para a produção de BGL foram 72 horas de incubação a 40 ° C, pH 6 e 50ml de meio de fermentação. Glicose (1%) e sulfato de amônio (3%) foram otimizados como melhores fontes de carbono e nitrogênio, respectivamente.


Assuntos
Aspergillus niger , Fermentação , Fungos , Glucosidases
6.
Biosci. j. (Online) ; 35(4): 1237-1244, july/aug. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1048926

RESUMO

Industrialization has added extremely toxic metalloid arsenic into the environment which at high concentration severely threatens the biota. Naturally, some microbes possess the ability to bio-accumulate metals and also to transform arsenite (As III) a toxic form to a non-toxic arsenate As V. The present study aimed to isolate arsenic resistant bacterias from the arsenic contaminated soil and water. Among eleven bacterial isolates, three FAs 1, 4 and 9 exhibited tolerance against sodium arsenite at 100mM concentration by achieving growth of 7.48×109,1.57×109 and 2.23×109 C.F.U./ml, respectively. Optimization at differentconditions such as temperature, pH and arsenic concentration revealed high arsenic tolerance from isolate FAs 4 (5.33×108) at 37°C and FAs 1 (4.43×108 C.F.U./ml) at pH 7. Arsenic resistance at optimum conditions for the bacterial strains FAs 1, FAs 4 and FAs 9 showed maximum growth at 80mM concentration of arsenite. These bacterial isolates did not show redox ability to oxidize arsenite As III to arsenate As V. However bacterial isolates FAs 1, FAs 4 and FAs 9 were able to accumulate arsenic 39.16, 148 and 125 µ g/L on the 4th, 3rd and 5thday of incubation, respectively. The isolates FAs 1, FAs 4 and FAs 9 were identified as Gram negative non endospore forming rods. In future, these novel isolates possess a great potential in biotechnology field, as bioremediation of arsenic contaminated soil and water can be done by employing arsenic accumulating bacteria which is an eco-friendly and cost effective method.


A industrialização adicionou arsênico metalóide extremamente tóxico ao ambiente que, em alta concentração, ameaça severamente a biota. Naturalmente, alguns micróbios possuem a capacidade de bio-acumular metais e também transformar arsenito (As III) uma forma tóxica a um arsenato não-tóxico Como V. O presente estudo visa o isolamento de bactérias resistentes ao arsênico do solo contaminado com arsênico e água . Entre onze isolados bacterianos, três FAs 1, 4 e 9 exibiram tolerância à concentração de 100 mM de arseatura de sódio, obtendo crescimento de 7,48 × 109,157 × 109 e 2,23 × 109 C.F.U./ml, respectivamente. Otimização em diferentes condições como temperatura, pH e concentração de arsênio revelaram alta tolerância ao arsênico do isolado FAs 4 (5,33 × 108) a 37 ° C e FAs 1 (4,43 × 108 UFC / ml) em pH 7. Resistência ao arsênico em condições ótimas para as cepas bacterianas FAs 1, FAs 4 e FAs 9 apresentaram crescimento máximo na concentração de 80 mM de arsenito. Estes isolados bacterianos não mostraram capacidade redoxpara oxidar o arsenito As III para arseniar como V. No entanto, os isolados bacterianos FAs 1, FAs 4 e FAs 9 foram capazes de acumular arsênico 39,16, 148 e 125 µ g / L no 4º, 3º e 5º dia de incubação, respectivamente. Os isolados FAs 1, FAs 4 e FAs 9 foram identificados como bastonetes gram-negativos não endoscópicos. No futuro, esses novos isolados possuem um grande potencial no campo da biotecnologia, já que a biorremediação de solo e água contaminados com arsênico pode ser feita empregando-se bactérias que acumulam arsênico, o que é um método ecologicamente correto e econômico.


Assuntos
Arsênio , Biodegradação Ambiental , Poluição Ambiental , Bioacumulação
7.
Biosci. j. (Online) ; 34(4): 1025-1032, july/aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-967254

RESUMO

The present study deals with the isolation screening and optimization of fungal strain for pectinase production. The fungal strains were isolated from different sources, including soil, fruits etc. Qualitative screening was performed on the basis of the pectin hydrolysis zone. While, quantitative screening was carried out employing submerged fermentation. Among all the strains the strains showing highest pectinolytic potential were selected identified and assigned the code Aspergillus niger ABT-5.The influence of different fermentation media on pectinase production was evaluated. The M5 medium containing 10g wheat bran, nutrient medium containing (g/l) of (NH4)2SO4 6.0, K2HPO4 6.0, KH2PO4 6.0, MgSO4.7H2O 0.1 gave the highest pectinase production. The other important physico chemical parameters including incubation period, temperature, and volume of media, size of inoculum, carbon and nitrogen sources were also optimized for pectinase production. The highest pectinase production (15.5U/ml) was obtained at 72h of incubation, pH 6, temperature 30°C, volume of media 50ml. Fructose and urea were designated as best carbon and nitrogen sources subsequently.


O presente estudo trata da triagem de isolamento e otimização da cepa fúngica para produção de pectinase. As cepas fúngicas foram isoladas de diferentes fontes, incluindo solo, frutas, etc. A triagem qualitativa foi realizada com base na zona de hidrólise da pectina. Enquanto, a triagem quantitativa foi realizada utilizando fermentação submersa. Entre todas as cepas, as cepas que apresentaram maior potencial pectinolítico foram selecionadas e atribuídas ao código Aspergillus niger ABT-5. Avaliou-se a influência de diferentes meios de fermentação na produção de pectinase. O meio M5 contendo 10g de farelo de trigo, meio nutriente contendo (g / l) de (NH4)2SO4 6.0, K2HPO4 6.0, KH2PO4 6.0, MgSO4.7H2O 0.1, proporcionou a maior produção de pectinase. Os outros parâmetros físico-químicos importantes, incluindo período de incubação, temperatura e volume dos meios, tamanho do inóculo, fontes de carbono e nitrogênio também foram otimizados para a produção de pectinase. A maior produção de pectinase (15,5U / ml) foi obtida às 72h de incubação, pH 6, temperatura 30 ºC, volume dos meios 50ml. A frutose e a ureia foram designadas como melhores fontes de carbono e nitrogênio posteriormente.


Assuntos
Poligalacturonase , Aspergillus niger , Triticum , Fermentação
8.
Biosci. j. (Online) ; 33(1): 57-65, jan./feb. 2017. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-965869

RESUMO

The current study was carried out to evaluate the effects of gamma irradiation on the epiphytic microflora and ripening process of the green Dwarf Cavendish bananas harvested at the three-quarter stage of the maturity. The mature green bananas were irradiated using Cobalt-60 as the source of irradiation at different dosages of 0.5, 0.75 and 1.0 kGy. The mean life of both the experimental and control group of fruits was analyzed under ambient conditions. For all the treatments the microbial potential, the decay percent and the ripening behavior of the fruits were recorded. Results revealed that the applied radiation doses reduced the decay incidence, delayed ripening process and greatly inhibit the microbial growth (total bacterial and fungal count) thereby enhancing the shelf life of bananas. Irradiation dose of 1.0 kGy was found to be the most effective dose to positively maintain the stored bananas under ambient conditions. The mean life of bananas was extended by 14 days. The identification of the enteric bacteriaeaceae through API 20 E strips revealed the presence of Shigella sonnie on the fruit surface along with Escherichia coli and a nonfermentor spp. The dominant spoilage causing fungi identified were Aspergillus niger, Aspergillus flavus, Collotrichum musae, Fusarium oxysporum,Mucor spp, Lasiodiplodia theobromea and Rhizopus stolonifer.


O Presente estudo foi realizado para investigar os efeitos da radiação gama sobre a microflora epífita e amadurecimento das bananas Cavendish Anão verde colhidas no estádio de três quartos da maturidade. As bananas verdes maduros foram irradiadas usando Cobalto-60 como fonte de irradiação a diferentes dosagens de 0,5, 0,75 e 1,0 kGy. A vida média de ambos os grupos experimental e de controlo de frutas foi analisada sob as condições ambientes. Para todos os tratamentos a potenciais microbiana, o percentual decadência e do comportamento do amadurecimento dos frutos foram recorded.Results revelou que as doses de radiação aplicadas reduziu a incidência de podridões, atrasou processo de amadurecimento e inibir significativamente o crescimento microbiano (contagem de bactérias e fungos total), assim aumentar a vida de prateleira das bananas. dose de irradiação de 1,0 kGy foi encontrada como sendo a dose mais eficaz para manter positivamente as bananas armazenada sob condições ambientes. A vida média de bananas foi prorrogado por 14 dias. A identificação do bacteriaeaceae entérico através de API 20 E tiras revelou a presença de Shigella sonnie sobre a superfície do fruto, juntamente com Escherichia coli e um nonfermentor spp. A deterioração dominante causando fungos identificados foram Aspergillus niger, Aspergillus flavus, Collotrichum musae, Fusarium oxysporum, Mucor spp, Lasiodiplodia theobromea e Rhizopus stolonifer.


Assuntos
Radiação Ionizante , Musa , Abastecimento de Alimentos
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