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1.
Molecules ; 27(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35807437

RESUMO

Enzymes that degrade pectin are called pectinases. Pectinases of microbial origin are used in juice clarification as the process is cost-effective. This study screened a pectinase-producing bacterium isolated from soil and identified as Bacillus subtilis 15A B-92 based on the 16S rRNA molecular technique. The purified pectinase from the isolate showed 99.6 U/mg specific activity and 11.6-fold purity. The molecular weight of the purified bacterial pectinase was 14.41 ± 1 kD. Optimum pectinase activity was found at pH 4.5 and 50 °C, and the enzyme was 100% stable for 3.5 h in these conditions. No enzymatic inhibition or activation effect was seen with Fe2+, Ca2+, or Mg2+. However, a slight inhibition was seen with Cu2+, Mn2+, and Zn2+. Tween 20 and 80 slightly inhibited the pectinase, whereas iodoacetic acid (IAA), ethylenediaminetetraacetate (EDTA), urea, and sodium dodecyl sulfate (SDS) showed potent inhibition. The bacterial pectinase degraded citrus pectin (100%); however, it was inactive in the presence of galactose. With citrus pectin as the substrate, the Km and Vmax were calculated as 1.72 mg/mL and 1609 U/g, respectively. The high affinity of pectinase for its substrate makes the process cost-effective when utilized in food industries. The obtained pectinase was able to clarify orange and apple juices, justifying its application in the food industry.


Assuntos
Bacillus subtilis , Poligalacturonase , Bacillus subtilis/genética , Concentração de Íons de Hidrogênio , Poligalacturonase/metabolismo , RNA Ribossômico 16S/genética , Temperatura
2.
Molecules ; 27(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35566068

RESUMO

The applications of bioactive compounds from medicinal plants as therapeutic drugs are largely increasing. The present study selected the bioactive compounds from Acacia concinna (A. concinna) and Citrus limon (C. limon) to assess their phytochemicals, proteins, and biological activity. The plant material was collected, and extraction performed as per the standard procedure. Qualitative analysis was undertaken, and identification of functional organic groups was performed by FTIR and HPLC. Antibacterial, anticancer, antioxidant, antihyperglycemic, antihyperlipidemic, and inhibition kinetics studies for enzymes were performed to assess the different biological activities. Flavonoids and phenols were present in a significant amount in both the selected plants. A. concinna showed significant antimicrobial activity against Z. mobilis, E. coli, and S. aureus, with minimum inhibition zones (MIZ) of 24, 22, and 20 mm, respectively. C. limon strongly inhibited all the tested pathogenic bacteria with maximum and minimum MIZ of 32 and 17 mm. A. concinna silver nanoparticles also exhibited potent antimicrobial activity. Both extracts showed substantial antioxidant, antihyperlipidemic, antidiabetic, anticancer (MCF-7), and anti-urease (antiulcer) properties. To conclude, these plants can be used to treat hyperlipidemia, diabetes, cancer, and gastrointestinal ulcers. They can also serve as antimicrobial and antioxidant agents. Thus, the studied plants must be exploited cost-effectively to generate therapeutic drugs for various diseases.


Assuntos
Acacia , Anti-Infecciosos , Citrus , Nanopartículas Metálicas , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Citrus/química , Escherichia coli , Hipolipemiantes , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/farmacologia , Staphylococcus aureus
3.
East Afr Health Res J ; 6(2): 203-207, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36751677

RESUMO

Background: Malaria presents a diagnostic challenge in most tropical countries including Rwanda. Microscopy remains the gold standard for diagnosing malaria, however, it is labour intensive and depends upon the skill of the examiner. Malaria rapid diagnostic tests (MRDTs) have been developed as an easy, convenient alternative to microscopy. Methods: A cross sectional study was conducted from October to November 2019 on 130 febrile patients who were directed to the laboratory department for blood screening for malaria parasites at Byumba Health centre. The main objective of this study was to correlate Microscopy and MRDTs in diagnosis of malaria. Results: After signing a consent form, blood samples were collected and screened for malaria parasites microscopically and by using MRDTs. Data collection forms were filled with relevant information and obtained results for MRDTs and for peripheral blood smear were recorded. The collected data were statistically analyzed using GraphPad Prism 9 software. The mean age found to be 16 years old. In this study peripheral blood smear microscopy was considered as a reference method. The sensitivity and specificity of RDT Histidine-Rich Protein 2 (HRP-2) were calculated and found to be 96.6% and 60% respectively. The negative predictive value was found to be 92.85% where positive predictive value was 73.3%. Conclusion: MRDTs should be used along with microscopy to avert complications associated with delayed diagnosis and similar studies are required to identify alternative techniques with high specificity for the diagnosis of malaria.

4.
Folia Microbiol (Praha) ; 66(1): 25-40, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33184763

RESUMO

Detergent enzymes are currently added to all powder and liquid detergents that are manufactured. Cellulases, lipases, amylases, and proteases are used in the detergency to replace toxic phosphates and silicates and to reduce high energy consumption. This makes the use of enzymes in detergent formulation cost effective. Fungi are producers of important extracellular enzymes for industrial use. The fungal and bacterial cellulases maintain the shape and color of the washed garments. There is a high demand for cellulases at the market by detergent industries. With this high demand, genetic engineering has been a solution due to its high production of detergent-compatible cellulases. Fungi are the famous source for detergent-compatible cellulases production, but still, there is a lack of the cost-effective process of alkaline fungal cellulase production. Review papers on detergent-compatible bacterial cellulase and amylase and detergent-compatible fungal and bacterial proteases and lipases are available, but there is no review on detergent fungal cellulases. This review aims to highlight the production, properties, stability, and compatibility of fungal cellulases. It will help other academic and industrial researchers to study, produce, and commercialize the fungal cellulases with good aspects.


Assuntos
Celulases/química , Detergentes/química , Proteínas Fúngicas/química , Celulases/genética , Celulases/isolamento & purificação , Celulases/metabolismo , Estabilidade Enzimática , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Fungos/genética , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Fungos/metabolismo , Engenharia Genética
5.
J Basic Microbiol ; 59(2): 134-147, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30421443

RESUMO

Cellulases, lipases, proteases, and amylases are employed in the detergent preparation to speed up the detergency process. Microbial cellulases are now commercially manufactured and are being used by various industries like detergent industry. Currently, the supplementation of detergent-compatible enzymes is a new trend followed by most of the detergent industries. The cellulases are supplemented to the detergents to improve the fabric smoothness and soil removal without damaging them. They act by passing through the textile interfibril spaces and thus the fabric quality is preserved. The process is environment friendly, and the use of cellulases and other detergent-compatible enzymes diminishes the utilization of toxic detergent constituents that are hazardous to humans. Alkaline cellulases active at ambient and low temperature are now preferred to maintain the fabric quality and use of low energy. The review reports on the production, purification, and properties studies of detergent-compatible proteases, amylases, and lipases are available. However, there is no report on detergent-compatible bacterial cellulases. In the present review, an overview on the production, purification, and characterization of detergent bacterial cellulases is presented. The stability and compatibility of the alkaline bacterial cellulases in the presence of the detergents and the detergent constituents are also discussed.


Assuntos
Bactérias/enzimologia , Celulases , Detergentes/química , Bactérias/classificação , Bactérias/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Biotecnologia , Carbono/metabolismo , Carboximetilcelulose Sódica/metabolismo , Celulases/classificação , Celulases/efeitos dos fármacos , Celulases/isolamento & purificação , Celulases/metabolismo , Temperatura Baixa , Meios de Cultura/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Metais/farmacologia , Nitrogênio/metabolismo , Especificidade por Substrato , Tensoativos/farmacologia , Têxteis
6.
J Basic Microbiol ; 55(10): 1149-58, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26011283

RESUMO

Most of the detergents that are presently produced contain the detergent compatible enzymes to improve and accelerate the washing performance by removing tough stains. The process is environment friendly as the use of enzymes in the detergent formulation reduces the utilization of toxic detergent constituents. The current trend is to use the detergent compatible enzymes that are active at low and ambient temperature in order to save energy and maintain fabric quality. As the detergent compatible bacterial enzymes are used together in the detergent formulation, it is important to co-produce the detergent enzymes in a single fermentation medium as the enzyme stability is assured, and production cost gets reduced enormously. The review reports on the production, purification, characterization and application of detergent compatible amylases, lipases, and proteases are available. However, there is no specific review or minireview on the concomitant production of detergent compatible amylases, lipases, and proteases. In this minireview, the coproduction of detergent compatible enzymes by bacterial species, enzyme stability towards detergents and detergent components, and stain release analysis were discussed.


Assuntos
Corantes , Detergentes/metabolismo , Estabilidade Enzimática , Amilases/metabolismo , Bactérias/enzimologia , Corantes/química , Ativação Enzimática , Fermentação , Lipase/metabolismo , Peptídeo Hidrolases/metabolismo , Temperatura
7.
3 Biotech ; 5(1): 61-70, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28324360

RESUMO

The possibility of using Aspergillus terreus protease in detergent formulations was investigated. Sodium dodecyl sulfate (SDS) and native polyacrylamide gel electrophoresis indicated that the purified alkaline protease (148.9 U/mg) is a monomeric enzyme with a molecular mass of 16 ± 1 kDa. This was confirmed by liquid chromatography-mass spectrometry. The active enzyme degraded the co-polymerized gelatin. The protease demonstrated excellent stability at pH range 8.0-12.0 with optimum at pH 11.0. It was almost 100 % stable at 50 °C for 24 h, enhanced by Ca2+ and Mg2+, but inhibited by Hg2+, and strongly inhibited by phenylmethyl sulfonyl fluoride. It showed maximum activity against casein followed by gelatin; its Vmax was 12.8 U/ml with its corresponding KM of 5.4 mg/ml. The proteolytic activity was activated by Tween-80, Triton-100 and SDS, and remained unaltered in the presence of H2O2 and NaClO. The enzyme exhibited higher storage stability at 4, 28 and -20 °C. It was stable and compatible to the desired level in the local detergents. The addition of the protease to the Super wheel improved its blood stain removal. The isolated protease can thus be a choice option in detergent industry.

8.
3 Biotech ; 5(6): 967-974, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28324401

RESUMO

A bacterium capable of degrading pendimethalin was isolated from the contaminated soil samples and identified as Bacillus lehensis XJU based on 16S rRNA gene sequence analysis. 6-Aminopendimethalin and 3,4-dimethyl 2,6-dinitroaniline were identified as the metabolites of pendimethalin degradation by the bacterium. The biodegradation of pendimethalin by freely suspended and the immobilized cells of B. lehensis on various matrices namely agar, alginate, polyacrylamide, and polyurethane foam was also investigated. The batch degradation rate was nearly the same for both free and immobilized cells in agar and alginate, whereas polyacrylamide- and PUF-immobilized cells degraded 93 and 100 of 0.1 % pendimethalin after 96 and 72 h, respectively. At higher concentration, the degradation rate of freely suspended cells decreased; whereas the same immobilized cells on polyurethane foam completely degraded 0.2 % pendimethalin within 96 h. The repeated batch degradation with the polyurethane foam-immobilized cells was reused for 35 cycles without losing the 0.1 % pendimethalin degrading ability. In contrast, agar-, alginate- and polyacrylamide-immobilized cells could be reused for 15, 18, and 25 cycles, respectively. When the pendimethalin concentration was increased to 0.2 %, the immobilized cells could be reused but the pendimethalin degradation rate was decreased. Polyurethane foam-immobilized cells exhibited better tolerance to pH and temperature alterations than freely suspended cells and could be stored for more than 3 months without losing pendimethalin degrading ability. The immobilization of cells capable of degrading pendimethalin may serve as an ideal technique for the complete degradation of the herbicide in the environment.

9.
Braz J Microbiol ; 45(3): 903-10, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25477924

RESUMO

A soil screened Bacillus flexus XJU-1 was induced to simultaneously produce alkaline amylase, alkaline lipase and alkaline protease at their optimum levels on a common medium under submerged fermentation. The basal cultivation medium consisted of 0.5% casein, 0.5% starch and 0.5% cottonseed oil as an inducer for protease, amylase, and lipase, respectively. The casein also served as nitrogen source for all 3 enzymes. The starch was also found to act as carbon source additive for both lipase and protease. Maximum enzyme production occurred on fermentation medium with 1.5% casein, 1.5% soluble starch, 2% cottonseed oil, 2% inoculum size, initial pH of 11.0, incubation temperature of 37 °C and 1% soybean meal as a nitrogen source supplement. The analysis of time course study showed that 24 h was optimum incubation time for amylase whereas 48 h was the best time for both lipase and protease. After optimization, a 3.36-, 18.64-, and 27.33-fold increase in protease, amylase and lipase, respectively was recorded. The lipase was produced in higher amounts (37.72 U/mL) than amylase and protease about 1.27 and 5.85 times, respectively. As the 3 enzymes are used in detergent formulations, the bacterium can be commercially exploited to secrete the alkaline enzymes for use in detergent industry. This is the first report for concomitant production of 3 alkaline enzymes by a bacterium.


Assuntos
Amilases/metabolismo , Bacillus/enzimologia , Bacillus/metabolismo , Proteínas de Bactérias/metabolismo , Detergentes/metabolismo , Endopeptidases/metabolismo , Inibidores Enzimáticos/metabolismo , Lipase/metabolismo , Bacillus/crescimento & desenvolvimento , Bacillus/isolamento & purificação , Carbono/metabolismo , Meios de Cultura/química , Fermentação , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Microbiologia do Solo , Temperatura , Fatores de Tempo
10.
Braz. j. microbiol ; 45(3): 903-910, July-Sept. 2014. ilus, graf
Artigo em Inglês | LILACS | ID: lil-727019

RESUMO

A soil screened Bacillus flexus XJU-1 was induced to simultaneously produce alkaline amylase, alkaline lipase and alkaline protease at their optimum levels on a common medium under submerged fermentation. The basal cultivation medium consisted of 0.5% casein, 0.5% starch and 0.5% cottonseedoil as an inducer forprotease, amylase, and lipase, respectively. The casein also served as nitrogen source for all 3 enzymes. The starch was also found to act as carbon source additive for both lipase and protease. Maximum enzyme production occurred on fermentation medium with 1.5% casein, 1.5% soluble starch, 2% cottonseed oil, 2% inoculum size, initial pH of 11.0, incubation temperature of 37 °C and 1% soybean meal as a nitrogen source supplement. The analysis of time course study showed that 24 h was optimum incubation time for amylase whereas 48 h was the best time for both lipase and protease. After optimization, a 3.36-, 18.64-, and 27.33-fold increase in protease, amylase and lipase, respectively was recorded. The lipase was produced in higher amounts (37.72 U/mL) than amylase and protease about 1.27 and 5.85 times, respectively. As the 3 enzymes are used in detergent formulations, the bacterium can be commercially exploited to secrete the alkaline enzymes for use in detergent industry. This is the first report for concomitant production of 3 alkaline enzymes by a bacterium.


Assuntos
Amilases/metabolismo , Bacillus/enzimologia , Bacillus/metabolismo , Proteínas de Bactérias/metabolismo , Detergentes/metabolismo , Endopeptidases/metabolismo , Inibidores Enzimáticos/metabolismo , Lipase/metabolismo , Bacillus/crescimento & desenvolvimento , Bacillus/isolamento & purificação , Carbono/metabolismo , Meios de Cultura/química , Fermentação , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Microbiologia do Solo , Temperatura , Fatores de Tempo
11.
Appl Biochem Biotechnol ; 174(4): 1215-1232, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25129040

RESUMO

Proteases, lipases, amylases, and cellulases are enzymes used in detergent formulation to improve the detergency. The amylases are specifically supplemented to the detergent to digest starchy stains. Most of the solid and liquid detergents that are currently manufactured contain alkaline enzymes. The advantages of using alkaline enzymes in the detergent formulation are that they aid in removing tough stains and the process is environmentally friendly since they reduce the use of toxic detergent ingredients. Amylases active at low temperature are preferred as the energy consumption gets reduced, and the whole process becomes cost-effective. Most microbial alkaline amylases are used as detergent ingredients. Various reviews report on the production, purification, characterization, and application of amylases in different industry sectors, but there is no specific review on bacterial or fungal alkaline amylases or detergent-compatible amylases. In this mini-review, an overview on the production and property studies of the detergent bacterial amylases is given, and the stability and compatibility of the alkaline bacterial amylases in the presence of the detergents and the detergent components are highlighted.


Assuntos
Amilases , Bactérias/enzimologia , Proteínas de Bactérias , Detergentes/química , Amilases/química , Amilases/isolamento & purificação , Amilases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo
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