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1.
Arch Microbiol ; 206(6): 245, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702537

RESUMO

Production of carotenoids by yeast fermentation is an advantaged technology due to its easy scaling and safety. Nevertheless, carotenoid production needs an economic culture medium and other efficient yeast stains. The study aims to isolate and identify a yeast strain capable of producing carotenoids using a cost-effective substrate. A new strain was identified as Rhodotorula toruloides L/24-26-1, which can produce carotenoids at different pretreated and unpretreated sugarcane molasses concentrations (40 and 80 g/L). The highest biomass concentration (18.6 ± 0.6 g/L) was reached in the culture using 80 g/L of hydrolyzed molasses. On the other hand, the carotenoid accumulation reached the maximum value using pretreated molasses at 40 g/L (715.4 ± 15.1 µg/g d.w). In this case, the ß-carotene was 1.5 times higher than that on the control medium. The yeast growth in molasses was not correlated with carotenoid production. The most outstanding production of The DPPH, ABTS, and FRAP tests demonstrated the antioxidant activity of the obtained carotenogenic extracts. This research demonstrated the R. toruloides L/24-26-1 strain biotechnological potential for carotenoid compounds. The yeast produces carotenoids with antioxidant activity in an inexpensive medium, such as sulfuric acid pretreated and unpretreated molasses.


Assuntos
Fermentação , Melaço , Rhodotorula , Saccharum , beta Caroteno , Rhodotorula/metabolismo , Rhodotorula/genética , Rhodotorula/crescimento & desenvolvimento , Rhodotorula/isolamento & purificação , Rhodotorula/classificação , Saccharum/metabolismo , beta Caroteno/metabolismo , beta Caroteno/biossíntese , Carotenoides/metabolismo , Antioxidantes/metabolismo , Biomassa , Meios de Cultura/química , Filogenia
2.
Reumatol Clin (Engl Ed) ; 17(8): 440-446, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34625146

RESUMO

OBJECTIVE: To determine the comorbidities associated with disability in patients with OA in Mexico (2013-2015). MATERIAL AND METHODS: A cross-sectional, retrospective and multicentre IMPACTAR study (n=7703) in Mexican patients (2013-2015). Comorbidities associated with disability were identified in 4971 patients diagnosed with OA from the IMPACTAR registry (n=7073). An adjusted logistic regression analysis was carried out by demographic, economic, clinical and medical variables. RESULTS: Mean age was 63 years; and 75% of the patients were women. Subjects with OA and presence of comorbidities are 42% more likely to develop disabilities than patients without associated comorbidity, considering age, sex, family income, OA diagnosis duration, and education level. The highest rate of people with disability (28.9%) was concentrated in Region 7, which corresponds to Mexico City. There are also significant differences between median family incomes, when the income of persons with disability is under $13 000 (IQR: 9000-16 000) Mexican pesos, compared to patients without disability. Almost half of the subjects (49.6%) reported having at least one comorbidity. Arterial hypertension was the risk factor with a statistically significant difference (32.8%) among those with disability (34.7%). CONCLUSIONS: Programs and interventions for OA patients should take into consideration comorbidity factors, being female, family income, and the region of residence as variables that may increase the possibility of developing an OA-associated disability.


Assuntos
Pessoas com Deficiência , Osteoartrite , Comorbidade , Estudos Transversais , Feminino , Humanos , México/epidemiologia , Pessoa de Meia-Idade , Osteoartrite/epidemiologia , Sistema de Registros , Estudos Retrospectivos
3.
Plants (Basel) ; 10(7)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206859

RESUMO

In Mexico, mistletoes have several applications in traditional medicine due to the great variety of compounds with biological activities that have not been characterized to date. The goals of the present study are to analyze the composition of minerals and phytochemical compounds in Mexican mistletoes Phoradendron bollanum and Viscum album subs. austriacum qualitatively and quantitatively, identify the compounds using HPLC-MS, and assess the antimicrobial potential in phytopathogenic microorganism control. Mineral content was evaluated with X-ray fluorescence. Three types of extracts were prepared: ethanol, water, and aqueous 150 mM sodium chloride solution. Characterization was carried out using qualitative tests for phytochemical compound groups, analytical methods for proteins, reducing sugars, total phenol, flavonoids quantification, and HPLC-MS for compound identification. The antimicrobial activity of mistletoe's liquid extracts was evaluated by microplate assay. K and Ca minerals were observed in both mistletoes. A qualitative test demonstrated alkaloids, carbohydrates, saponins, flavonoids, tannins, and quinones. Ethanolic extract showed flavonoids, 3845 ± 69 and 3067 ± 17.2 mg QE/g for Phoradendron bollanum and Viscum album subs. austriacum, respectively, while aqueous extracts showed a total phenol content of 65 ± 6.9 and 90 ± 1.19 mg GAE/g Phoradendron bollanum and Viscum album subs. austriacum, respectively. HPLC-MS identified largely hydroxycinnamic acids and methoxycinnamic acids. Clavibacter michiganenses was successfully inhibited by aqueous extract of both mistletoes.

4.
Front Bioeng Biotechnol ; 9: 793340, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35198549

RESUMO

The present review describes the basic properties of colloidal and vesicular vehicles that can be used for immobilization of enzymes. The thermodynamic aspects of the immobilization of enzymes (laminarinase and chitinase) in liposomes are discussed. These systems protect enzymes against environmental stress and allow for a controlled and targeted release. The diversity of colloidal and vesicular carriers allows the use of enzymes for different purposes, such as mycolytic enzymes used to control phytopathogenic fungi.

5.
Biotechnol Rep (Amst) ; 26: e00471, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32509541

RESUMO

This work describes the successful extraction of Aspergillus niger phytase from a crude extract (CE) obtained from solid-state fermentation by reversed micelle system using anionic surfactant sodium bis (2-ethylhexyl) sulfosuccinate (AOT) in isooctane achieved in two simple steps: forward and backward extractions. The effects of potassium chloride (KCl) concentration, pH of the aqueous solution, and AOT concentration that affect the system were examined. The best result for the forward extraction was obtained with the CE solution at pH 4.0, 50 mM KCl, and 100 mM AOT, while for the backward extraction the best result was achieved with a stripping aqueous solution at pH 5.5 containing 200 mM KCl, achieving a purification factor of 4.03, 1.15 times higher than that reported for the conventional purification process. Phytase purity was demonstrated by SDS-PAGE (89 kDa) and its activity by zymogram, confirming the efficiency of the process with low time consumption (∼40 min).

6.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32563732

RESUMO

OBJECTIVE: To determine the comorbidities associated with disability in patients with OA in Mexico (2013-2015). MATERIAL AND METHODS: A cross-sectional, retrospective and multicentre IMPACTAR study (n=7703) in Mexican patients (2013-2015). Comorbidities associated with disability were identified in 4971 patients diagnosed with OA from the IMPACTAR registry (n=7073). An adjusted logistic regression analysis was carried out by demographic, economic, clinical and medical variables. RESULTS: Mean age was 63 years; and 75% of the patients were women. Subjects with OA and presence of comorbidities are 42% more likely to develop disabilities than patients without associated comorbidity, considering age, sex, family income, OA diagnosis duration, and education level. The highest rate of people with disability (28.9%) was concentrated in Region 7, which corresponds to Mexico City. There are also significant differences between median family incomes, when the income of persons with disability is under $13 000 (IQR: 9000-16 000) Mexican pesos, compared to patients without disability. Almost half of the subjects (49.6%) reported having at least one comorbidity. Arterial hypertension was the risk factor with a statistically significant difference (32.8%) among those with disability (34.7%). CONCLUSIONS: Programs and interventions for OA patients should take into consideration comorbidity factors, being female, family income, and the region of residence as variables that may increase the possibility of developing an OA-associated disability.

7.
Foods ; 9(3)2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32138215

RESUMO

The multifunctional properties of autochthonous lactic acid bacteria can be of use for enhancing the sensorial properties of food, as well as in food preservation. An initial screening for antimicrobial, proteolytic, and lipolytic capacities was done in 214 presumptive lactic acid bacteria isolates obtained from Chihuahua cheese manufacturing and during a ripening period of nine months. The antimicrobial screening was done by spot-on-the-lawn tests, using Listeria monocytogenes and Escherichia coli as indicator microorganisms; proteolysis was tested in casein-peptone agar and lipolysis in Mann-Rogosa-Sharpe (MRS)-tributyrin agar. More than 90% of the isolates hydrolyzed the casein, but only 30% hydrolyzed tributyrin; the inhibition of L. monocytogenes in the spot-on-the-lawn assay was used to select 39 isolates that had a bigger inhibition zone (>11.15 mm ± 0.3) than the control (Nisin producer Lactococcus lactis BS-10 Chr Hansen). The selected isolates were grown in MRS to obtain the neutralized cell-free supernatants and verify their antimicrobial activity by agar diffusion and the percentage of growth inhibition techniques. The selected isolates were also growth in casein peptone broth, and the cell-free supernatants were used for the determination of antioxidant activity by the radical scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) techniques. The results were analyzed to identify similarities by cluster analysis, based on their antimicrobial and antioxidant capacities. The isolates were arranged into six clusters; one cluster that included 12 isolates demonstrated L. monocytogenes (784-2811 mm2/mL AU by agar diffusion assay) and E. coli (41%-47% growth inhibition) antimicrobial activity. The isolates clustered in these groups also showed competitive inhibition of both radicals (11%-19% of DPPH and 50%-60% of ABTS). The isolates from cluster one were also identified by 16S rDNA amplification and were identified as Enterococcus faecium. Traditional products such as Chihuahua cheese can be a source or lactic acid bacteria with metabolic properties that can be used in food preparation and preservation.

8.
Med. interna Méx ; 34(3): 443-476, may.-jun. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-976088

RESUMO

Resumen La osteoartritis es una enfermedad articular crónica degenerativa, es la afección articular observada con más frecuencia en la población adulta y una de las principales causas de discapacidad en todo el mundo, por lo que es de importancia el diagnóstico y tratamiento en las fases tempranas de la enfermedad. En la actualidad los nuevos tratamientos, además de aliviar el dolor, pueden disminuir la limitación funcional y modificar el curso de la enfermedad. El objetivo de este artículo es actualizar la evidencia acerca del diagnóstico y de las nuevas formas de tratamiento de la osteoartritis, así como evaluar los cambios en la evidencia que ha habido en relación con la guía anterior. Para la elaboración de la guía motivo de esta reunión, se contó con la participación de especialistas en Medicina Interna, Reumatología, Ortopedia y Rehabilitación física, un bibliotecario y un experto en metodología; se realizó una búsqueda extensa en PubMed y en otros sitios web especializados. Se estableció una serie de recomendaciones y niveles de evidencia basados en la bibliografía consultada. Se concluye que la osteoartritis es una enfermead compleja que implica múltiples factores de riesgo, por lo que es importante tomar en cuenta que el tratamiento es multidisciplinario y consta de un enfoque no farmacológico y uno farmacológico; sin embargo, es necesario crear una cultura preventiva de la osteoartritis en los médicos tratantes, en la que se eduque y se dé información al paciente para evitar que la enfermedad progrese.


Abstract Osteoarthritis, a chronic degenerative joint disease, is the joint condition most frequently observed in the adult population; is one of the leading causes of disability worldwide. Therefore, it is important the diagnosis and treatment in the early stages of the disease. Currently new therapies, in addition to relieving pain, can reduce functional limitation and modify the course of the disease. The objective of this article is to update the evidence on diagnosis and new forms of osteoarthritis treatment, as well as to evaluate the changes in the evidence that has been in relation to the previous guide. For the elaboration of the guide, there was participation of specialists (Internal Medicine, Rheumatology, Orthopedics and Physical Rehabilitation), a librarian and an expert in methodology; an extensive search was carried out in PubMed and other specialized websites. A series of recommendations and levels of evidence were established based on the bibliography consulted. Concluding that osteoarthritis is a complex pathology involving multiple risk factors, it is important to consider that the treatment is multidisciplinary and consists of a non-pharmacological approach and a pharmacological treatment; however, it is necessary to create a preventive culture on osteoarthritis in treating doctors, in which the patient is educated and given information to prevent the disease from progressing.

9.
Plant Foods Hum Nutr ; 69(1): 65-70, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24445672

RESUMO

In vitro effect of betulin-containing extract from Betula pendula Roth. bark on alpha-amylase activity was studied, the kinetic mechanism of interaction was proposed and in vivo effect of betulin-containing extract on weight gain and meat quality of broiler chickens was evaluated. The highest level of inhibitory activity (20%) was detected in extract concentration of 1,000 mg/L. Increased extract concentration did not lead to increased enzyme inhibition. Using Dixon and Cornish-Bowden coordinates, the competitive mechanism of inhibition was demonstrated. Calculated kinetic parameters were: Km equal to 0.6 mg/mL, Vmax equal to 2.6 and 2.1 mM/min from Lineweaver-Burk and Dixon coordinates, respectively and Ki equal to 3,670 ± 230 mg/mL. The partial inhibition of enzyme indicates the existence of low concentration of active inhibitory form, which reaches saturation level with increased extract concentration in applied suspension. Therefore, Ki has an apparent constant character. This partial inhibition of amylase activity observed in in vitro assay did not affect weight gain and meat quality of broiler chickens during in vivo assay. Rather, the tendency to increase the weight of edible parts and muscles compared to diet without additive suggests that the extract may be a potential food additive in poultry farming. Additionally, it could be a source for further pharmaceutical and pharmacological research.


Assuntos
Betula/química , Inibidores Enzimáticos/farmacologia , Carne/análise , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Aumento de Peso/efeitos dos fármacos , alfa-Amilases/antagonistas & inibidores , Animais , Galinhas , Dieta , Casca de Planta/química
10.
Appl Biochem Biotechnol ; 160(7): 2045-53, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19768388

RESUMO

The production of extracellular and mycelia-associated penicillin G acylase (maPGA) with Mucor griseocyanus H/55.1.1 by surface-adhesion fermentation using Opuntia imbricata, a cactus, as a natural immobilization support was studied. Enzyme activity to form 6-aminopencillanic acid (6-APA) from penicillin G was assayed spectrophotometrically. The penicillin G hydrolysis to 6-APA was evaluated at six different times using PGA samples recovered from the skim milk medium at five different incubation times. Additionally, the effect of varying the penicillin G substrate concentration level on the PGA enzyme activity was also studied. The maximum reaction rate, V (max), and the Michaelis constant, K (M), were determined using the Michaelis-Menten model. The maximum levels for maPGA and extracellular activity were found to be 2,126.50 international unit per liter (IU/l; equal to 997.83 IU/g of support) at 48 h and 755.33 IU/l at 60 h, respectively. Kinetics of biomass production for total biomass showed a maximum growth at 60 h of 3.36 and 2.55 g/l (equal to 0.012 g of biomass per gram of support) for the immobilized M. griseocyanus biomass. The maPGA was employed for the hydrolysis of penicillin G to obtain 6-APA in a batch reactor. The highest quantity of 6-APA obtained was 226.16 mg/l after 40-min reaction. The effect of substrate concentration on maPGA activity was evaluated at different concentrations of penicillin G (0-10 mM). K(M) and V(max) were determined to be 3.0 x 10(-3) M and 4.4 x 10(-3) mM/min, respectively.


Assuntos
Enzimas Imobilizadas/biossíntese , Fermentação , Ácido Penicilânico/análogos & derivados , Penicilina Amidase/biossíntese , Penicilina G/química , Biofilmes , Adesão Celular , Ativação Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Hidrólise , Opuntia/enzimologia , Ácido Penicilânico/síntese química , Ácido Penicilânico/química , Ácido Penicilânico/metabolismo , Penicilina Amidase/química , Penicilina Amidase/metabolismo , Penicilina G/metabolismo , Propriedades de Superfície
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