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1.
J Sci Food Agric ; 104(2): 759-768, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37658688

RESUMO

BACKGROUND: Kombucha is a popular fermented drink with therapeutic benefits. The present study aimed to examine the fermentation of turmeric-infused kombucha and evaluate its biological activities and functional properties. RESULTS: The study of pH dynamics during fermentation found that turmeric kombucha has a lower pH decrease than standard kombucha, with the lowest pH of 3.1 being observed in 0.1% turmeric kombucha and the maximum pH of 3.8 found in 1% turmeric kombucha. The research shows that the symbiotic consortia of bacteria and yeast alters during the fermentation process with turmeric. Gas chromatogrphy-mass spectrometry analysis revealed that turmeric kombucha is abundant in terpenes, ketones, alcohols, aldehydes, phenols and fatty acids, with higher levels of active ingredients than regular kombucha. The kombucha with 0.6% turmeric had the highest overall acceptance score (9.0) in sensory evaluation. The total phenolic content after fermentation was in the range 0.2-0.8 mg gallic acid equivalents mL-1 . Increasing turmeric concentrations increased the antioxidant, cytotoxic and antibacterial activity of kombucha analogs, with the highest antioxidant activity (89%) observed at 0.8% turmeric, and the maximum cytotoxicity (74%) and antibacterial activity (zones of inhibition of 17.7 and 15.9 mm against Staphylococcus aureus and Escherichia coli, respectively) observed at 1% turmeric. CONCLUSION: The fermentation of kombucha infused with turmeric enhanced its biological activities, making it a healthier alternative to traditional kombucha and presenting new opportunities in the field of functional foods. Further investigations into the mechanisms underlying these effects and in vivo studies are warranted to fully comprehend the impact of turmeric kombucha consumption on human health. © 2023 Society of Chemical Industry.


Assuntos
Bactérias , Curcuma , Humanos , Fermentação , Fenóis , Antibacterianos/farmacologia , Escherichia coli
2.
J Basic Microbiol ; 63(3-4): 404-416, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35849112

RESUMO

Chitosanases are potential candidates for chitooligosaccharides (COS) production-based industries, therefore, the discovery of chitosanases having commercial potential will remain a priority worldwide. This study aims to characterize different chitosanases of Bacillus strains for COS production. Six different indigenous Bacillus strains (B. cereus EGE-B-6.1m, B. cereus EGE-B-2.5m, B. cereus EGE-B-5.5m, B. cereus EGE-B-10.4i, B. thuringiensis EGE-B-3.5m, and B. mojavensis EGE-B-5.2i) were used to purify and characterize chitosanases. All purified chitosanases have a similar molecular weight (37 kDa) as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, other characteristics such as optimum temperature and pH, kinetic parameters (Km and Vmax ), temperature, and pH stabilities were dissimilar among the strains of different Bacillus species and within the same species. Furthermore, chitosanases of all strains were able to successfully hydrolyze chitosan to COS and oligomers of the degree of polymerization 2-6 were detected with chitobiose and chitotriose as major hydrolysis products. The relative yields of COS were in a range of 19%-31% and chitosanase of B. thuringiensis EGE-B-3.5m turned out to be the best enzyme in terms of its characteristics and COS production potential with maximum relative yield (31%). Results revealed that Bacillus chitosanases could be used directly for efficient bioconversion of chitosan into COS and will be valuable for large-scale production of biologically active COS.


Assuntos
Bacillus , Quitosana , Quitosana/química , Quitina , Glicosídeo Hidrolases
3.
J Basic Microbiol ; 58(10): 836-847, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30022499

RESUMO

Maximum production of industrially important enzymes such as chitosanases through media optimization still holds foremost interest. The present study was conducted to improve chitosanase activity of an indigenous strain identified as Bacillus mojavensis. Initially, carbon and nitrogen sources were optimized by one-variable-at-a-time approach. Further, fermentation medium was optimized using Plackett-Burman (PB) and central composite designs (CCD). PB verified soluble starch (SS), colloidal chitosan (CC) peptone, and NaCl as most significant variables affecting chitosanase production. CCD results predicted the optimum concentrations of SS, CC, peptone, and NaCl as 7.8, 7.0, 6.5, and 2.7 g L-1 , respectively to achieve maximum chitosanase activity (21.1 U ml-1 ). Discovery of the novel optimal medium has improved chitosanase production by B. mojavensis up-to 9.5 folds. Lastly, 18.6 U ml-1 chitosanase activity was achieved in stirred tank bioreactor using optimal medium, which is quite satisfactory to proclaim this strain as a potential candidate to provide commercial chitosanase.


Assuntos
Bacillus/enzimologia , Proteínas de Bactérias/biossíntese , Reatores Biológicos , Glicosídeo Hidrolases/biossíntese , Microbiologia Industrial/métodos , Bacillus/crescimento & desenvolvimento , Proteínas de Bactérias/metabolismo , Quitosana/metabolismo , Meios de Cultura/química , Meios de Cultura/metabolismo , Fermentação , Glicosídeo Hidrolases/metabolismo , Reprodutibilidade dos Testes
4.
Pak J Pharm Sci ; 28(3): 997-1004, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26004734

RESUMO

Vancomycin resistant Staphylococcus aureus (VRSA) has been reported from many parts of the world including Asian countries. Hence, main objective of study was to evaluate the possible occurrence of VRSA in hospitals of Lahore city and to ensure the effectiveness of various substitute therapeutic options. A total of 150 samples of pus/wounds were collected from three hospitals of the city and VRSA were isolated and confirmed through recommended method of Clinical and Laboratory Standards Institute. Out of 51 (49.04%) methicillin resistant S. aureus (MRSA) isolates, 5 (9.8%) were found resistant to vancomycin. Minimum inhibitory concentration (MIC) of Linezolid (LZD), Moxifloxacin (MFX) and Clindamycin (CD) were calculated against VRSA isolates by broth microdilution test. All 5 (100%) isolates were susceptible to Linezolid and Clindamycin, while 4 (80%) were susceptible to Moxifloxacin. Ethanolic extracts of Turmeric, Mint, Coriander, Garlic, Kalonji, Cinnamon and Cloves illustrate average MIC values of 140.8 µg/mL, 563.2 µg/mL, 486.4 µg/mL, 614.4 µg/mL, 409.6 µg/mL, 281.6 µg/mL and 64 µg/mL, respectively against 5 VRSA strains. Concentration dependent increase in growth inhibition zones of ethanolic plant extract was recorded by agar well diffusion test. This study was helpful to find out the effective antibiotic against VRSA. Plant extracts encompass anti-staphylococcal activity and this finding demands necessity of further exploration of potential found in these natural herb.


Assuntos
Acetamidas/farmacologia , Antibacterianos/farmacologia , Clindamicina/farmacologia , Fluoroquinolonas/farmacologia , Oxazolidinonas/farmacologia , Extratos Vegetais/farmacologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Infecção da Ferida Cirúrgica/microbiologia , Resistência a Vancomicina , Cinnamomum zeylanicum , Curcuma , Alho , Humanos , Linezolida , Mentha , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Moxifloxacina , Nigella sativa , Paquistão , Staphylococcus aureus/isolamento & purificação , Syzygium , Infecção dos Ferimentos/microbiologia
5.
Pak J Pharm Sci ; 28(4): 1295-300, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26142503

RESUMO

Increasing incidence rate of multiple drug resistance in Escherichia coli (E. coli) due to extensive uses of antibiotics is a serious challenge to disease treatment. Contaminated retail chicken meat is one of the major sources of spread of multi drug resistant (MDR) E. coli. Current study has been conducted to study the prevalence of MDR E. coli in retail chicken meat samples from Lahore city of Pakistan and it was found that 73.86% of E. coli isolates have MDR pattern. In vitro evaluation of antibacterial activity of crude ethanolic extracts of six herbs against MDR E. coli phenotypes has revealed that clove and cinnamon have maximum zones of inhibition as compared to other herbal extracts. Mint and coriander gave the intermediate results while garlic and kalonji showed the least antibacterial activity against the MDR E. coli phenotypes using the agar well diffusion technique. Average Minimum Inhibitory Concentrations (MICs) for clove, mint, cinnamon, coriander, kalonji and garlic extracts were 1.15, 1.38, 0.5, 1.99, 2.41, 8.60 mg/mL respectively using the broth micro dilution method. The results obtained in present study were revealed that crude ethanol extracts of selected herbs have had significant antibacterial activity. Hence they can be used as promising alternatives of antimicrobials against MDR E. coli species and can be used for cooked food preservation.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Carne/microbiologia , Extratos Vegetais/farmacologia , Animais , Galinhas , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana
6.
Int J Biol Macromol ; 249: 125916, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37527764

RESUMO

Glycosyltransferases (GTs) catalyze the transfer of active monosaccharide donors to carbohydrates to create a wide range of oligosaccharide structures. GTs display strong regioselectivity and stereoselectivity in producing glycosidic bonds, making them extremely valuable in the in vitro synthesis of oligosaccharides. The synthesis of oligosaccharides by GTs often gives high yields; however, the enzyme activity may experience product inhibition. Additionally, the higher cost of nucleotide sugars limits the usage of GTs for oligosaccharide synthesis. In this review, we comprehensively discussed the structure and mechanism of GTs based on recent literature and the CAZY website data. To provide innovative ideas for the functional studies of GTs, we summarized several remarkable characteristics of GTs, including folding, substrate specificity, regioselectivity, donor sugar nucleotides, catalytic reversibility, and differences between GTs and GHs. In particular, we highlighted the recent advancements in multi-enzyme cascade reactions and co-immobilization of GTs, focusing on overcoming problems with product inhibition and cost issues. Finally, we presented various types of GT that have been successfully used for oligosaccharide synthesis. We concluded that there is still an opportunity for improvement in enzymatically produced oligosaccharide yield, and future research should focus on improving the yield and reducing the production cost.


Assuntos
Carboidratos , Glicosiltransferases , Glicosiltransferases/química , Açúcares , Monossacarídeos , Oligossacarídeos , Nucleotídeos
7.
Front Nutr ; 10: 1279552, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38375356

RESUMO

The sustainable extraction of natural compounds has recently attracted significant attention. The extraction of high-quality natural vanillin in active form is crucial for its efficient use in various industries, but conventional solvents are not suitable for this purpose. The flammability, volatility, and toxicity of organic solvents can harm extraction personnel, and their waste liquid can cause environmental pollution. Natural deep eutectic solvents (NADES) are cost-effective, environmentally friendly, biodegradable, and non-toxic organic alternative to conventional solvents. In this study, 20 different NADES were tested for the sustainable extraction of natural vanillin. Among these, a DES system composed of choline chloride: 1,4-butanediol: lactic acid exhibited the highest extraction rate (15.9 mg/g). Employing response surface methodology (RSM), optimal extraction conditions were determined, yielding a vanillin content 18.5 mg/g with water content of 33.9%, extraction temperature of 64.6°C, extraction time of 32.3 min, and a solid-liquid ratio of 44.9 mg/mL. Subsequently, the optimized NADES system was then assessed for reusability in extracting vanillin from vanilla pods and kraft lignin over three cycles, retaining 43% of its extraction efficiency and demonstrating potential for waste reduction. Purification of vanillin was achieved through chromatography using a non-polar resin SP700, with ethanol as a desorption eluent and a feed solution pH of 4.0, resulting in the highest vanillin purity. HPLC and GC-MS analyses confirmed purity, while antioxidant activity assays (DPPH and ABTS) showcased significant antioxidant activity of the purified vanillin. Moreover, vanillin exhibited notable antimicrobial activity against a panel of food-borne bacteria. This study introduces an environmentally friendly approach to vanillin extraction highlights using NADES, emphasizing the potential for producing high-quality bioactive vanillin with reduced environmental impact. The applicability of NADES systems extends beyond vanillin, offering a versatile method for extracting diverse natural compounds.

8.
Biotechnol J ; 18(10): e2300095, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37377135

RESUMO

This study investigates the development of dual-substrate mixotrophy strategy to cultivate the microalga Haematococcus lacustris for astaxanthin production. The influence of different concentrations of acetate and pyruvate on biomass productivity was first assessed individually, and then both substrates were used together to improve biomass growth in the green phase and astaxanthin accumulation in red the phase. The results showed that dual-substrates mixotrophy significantly increased the biomass productivity during green growth phase up to 2-fold compared to phototrophic controls. Furthermore, supplementation of dual-substrate to the red phase increased astaxanthin accumulation by 10% in the dual-substrate group compared to single-substrate acetate and no substrate. This dual-substrate mixotrophy approach shows promise for cultivating Haematococcus for commercial production of biological astaxanthin in indoor closed systems.


Assuntos
Clorófitas , Microalgas , Xantofilas , Biomassa , Acetatos
9.
Front Bioeng Biotechnol ; 9: 740533, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34676203

RESUMO

Although Haematococcus lacustris has been developed for astaxanthin production for decades, the production cost is still high. In order to modify the production processes, we proposed a novel strategy of cultivation, featured by sequential indoor continuous mixotrophic cultivation for the production of green cells followed by outdoor phototrophic induction for astaxanthin accumulation. The continuous mixotrophic cultivation was first optimized indoor, and then the seed culture of mixotrophic cultivation was inoculated into outdoor open raceway ponds for photoinduction. The results showed that mixotrophically grown cultures could efficiently grow without losing their photosynthetic efficiency and yielded higher biomass concentration (0.655 g L-1) and astaxanthin content (2.2% DW), compared to phototrophically grown seed culture controls. This novel strategy might be a promising alternative to the current approaches to advance the production technology of astaxanthin from microalgae.

10.
Front Bioeng Biotechnol ; 9: 752024, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858957

RESUMO

This study involves evaluation of two native cyanobacterial strains Euryhalinema and Desertifilum isolated from a mangrove pond in Haikou (China) for their possible phycocyanin (C-PC) production. Maximal growth rate with highest chlorophyll and C-PC accumulation were observed at 28°C and 60 µmol photons m-2 s-1 photon flux density for Euryhalinema sp., while for Desertifilum sp. at 32°C and 80 µmol photons m-2 s-1. Nitrogen and iron concentration trails revealed that double strength concentration of sodium nitrate and ferric ammonium citrate in original BG11 media increased growth rate and accumulation of C-PC for both strains. Three different C-PC extraction methods were tested. The combined extraction protocol of freeze-thaw and ultrasonication markedly increased the C-PC extraction efficiency and attained the food grade purity (A 620/A 280 ratio >0.7), whereas a higher C-PC yield was found with Na-phosphate buffer. Furthermore, the clarified crude extract was used to purify C-PC by fractional ammonium sulfate [(NH4)2SO4] precipitation, Sephadex G-25 gel filtration chromatography, and DEAE-sephadex ion exchange chromatography and attained analytical grade purity (A 620/A 280 ratio >3.9). Taken together, both strains showed their potential to be domesticated for valuable phycocyanin production.

11.
Methods Mol Biol ; 1980: 173-179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30484147

RESUMO

Phycocyanin is a blue-colored pigment-protein complex that exhibits numerous biofunctions such as anti-inflammation, antioxidation, antitumor, neuroprotective effect, and immunological enhancement. Purified phycocyanin has pharmaceutical and nutraceutical applications. In addition, as a nontoxic and non-carcinogenic natural coloring agent, phycocyanin has many applications in the food and cosmetic industries. This chapter describes a protocol for extraction and analytical grade purification of phycocyanin from cyanobacteria. The purification steps include (1) extraction of phycocyanin from biomass, (2) ammonium sulfate precipitation of phycocyanin and dialysis, and (3) purification of phycocyanin by gel filtration and ion-exchange chromatography.


Assuntos
Cianobactérias/metabolismo , Ficocianina/biossíntese , Ficocianina/isolamento & purificação , Sulfato de Amônio , Cromatografia em Gel , Cromatografia por Troca Iônica , Precipitação Fracionada , Extração Líquido-Líquido , Ficocianina/análise
12.
Carbohydr Polym ; 184: 243-259, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29352917

RESUMO

Chitin is the most abundant natural polysaccharide and chitosan is its most important derivative. Regardless of having various bioactivities, the water insolubilities of chitin and chitosan limit their applications in many industries. The physical, chemical or enzymatic depolymerization of chitin and chitosan deliver chitooligosaccharides (COS): water-soluble and low molecular weight derivatives, superior to the parent polymers in multiple aspects. COS exhibit an enormously wide range of biological activities and a remarkable potential to be applied in various industries. This review has fully addressed the latest research on the biological activities of COS and the molecular mechanism behind these activities in a correlation with their physicochemical properties. Furthermore, an attempt has been made to report the commercially available COS products. The bioactivities discussed here may offer new understanding of the applications of COS in numerous sectors.


Assuntos
Quitina/análogos & derivados , Quitina/química , Quitosana/química , Peso Molecular , Oligossacarídeos
13.
AIMS Microbiol ; 3(3): 467-482, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-31294171

RESUMO

Biodegradation requires identification of hydrocarbon degrading microbes and the investigation of psychrotolerant hydrocarbon degrading microbes is essential for successful biodegradation in cold seawater. In the present study, a total of 597 Bacillus isolates were screened to select psychrotolerant strains and 134 isolates were established as psychrotolerant on the basis of their ability to grow at 7 °C. Hydrocarbon degradation capacities of these 134 psychrotolerant isolate were initially investigated on agar medium containing different hydrocarbons (naphthalene, n-hexadecane, mineral oil) and 47 positive isolates were grown in broth medium containing hydrocarbons at 20 °C under static culture. Bacterial growth was estimated in terms of viable cell count (cfu ml-1). Isolates showing the best growth in static culture were further grown in presence of crude oil under shaking culture and viable cell count was observed between 8.3 × 105-7.4 × 108 cfu ml-1. In the final step, polycyclic aromatic hydrocarbon (PAH) (chrysene and naphthalene) degradation yield of two most potent isolates was determined by GC-MS along with the measurement of pH, biomass and emulsification activities. Results showed that isolates Ege B.6.2i and Ege B.1.4Ka have shown 60% and 36% chrysene degradation yield, respectively, while 33% and 55% naphthalene degradation yield, respectively, with emulsification activities ranges between 33-50%. These isolates can be used to remove hydrocarbon contamination from different environments, particularly in cold regions.

14.
3 Biotech ; 6(2): 120, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28330195

RESUMO

Endophytes are microorganisms which live symbiotically with almost all varieties of plant and in turn helping the plant in a number of ways. Instead of satisfactory surface sterilization approaches, repeatedly occurring bacterial growth on in vitro rootstock cultures of peach and pear was identified and isolated as endophytic bacteria in our present study. Five different isolates from peach rootstocks were molecularly identified by 16S rRNA gene sequencing as Brevundimonas diminuta, Leifsonia shinshuensis, Sphingomonas parapaucimobilis Brevundimonas vesicularis, Agrobacterium tumefaciens while two endophytic isolates of pear were identified as Pseudoxanthomonas mexicana, and Stenotrophomonas rhizophilia. Identified endophytes were also screened for their potential of plant growth promotion according to indoleacetic acid (IAA) production, nitrogen fixation, solubilization of phosphate and production of siderophore. All seven endophytic isolates have shown positive results for IAA, nitrogen fixation and phosphate solubilization tests. However, two out of seven isolates showed positive results for siderophore production. On the basis of these growth promoting competences, isolated endophytes can be presumed to have significant influence on the growth of host plants. Future studies required to determine the antimicrobial susceptibility profile and potential application of these isolates in biological control, microbial biofertilizers and degradative enzyme production.

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