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1.
Biotechnol Lett ; 35(8): 1309-15, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23636861

RESUMEN

Blakeslea trispora powder that contains 1.9 % lycopene was tested for its anti-aging effect on adult mice. 48 adult mice were administered with the powder at 0, 267, 534, 1,068 mg lycopene kg(-1) body daily for 30 days. The body weight, hematology, clinical chemical and antioxidant activities in major organs of adult mice were measured. The powder had no effect on the body weight, hematology, clinical chemical parameters of adult mice but improved the antioxidant activities in major organs of adult mice. Increased activities of superoxide dismutase, catalase and glutathione peroxidase and a decreased amount of malondialdehyde in liver, brain, kidney and skin of adult mice when a high-dose of the B. trispora powder was administered, suggests that it has the ability to enhance the antioxidation system and improve the anti-aging abilities of adult mice.


Asunto(s)
Envejecimiento , Antioxidantes/administración & dosificación , Carotenoides/administración & dosificación , Mucorales/química , Polvos/administración & dosificación , Animales , Licopeno , Ratones
2.
AMB Express ; 13(1): 93, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37665384

RESUMEN

The biosynthetic process of selenium nanoparticles (SeNPs) by specific bacterial strain, whose growth directly affects the synthesis efficiency, has attracted great attentions. We previously reported that Bacillus paralicheniformis SR14, a SeNPs-producing bacteria, could improve intestinal antioxidative function in vitro. To further analyze the biological characteristics of SR14, whole genome sequencing was used to reveal the genetic characteristics in selenite reduction and sugar utilization. The results reviewed that the genome size of SR14 was 4,448,062 bp, with a GC content of 45.95%. A total of 4300 genes into 49 biological pathways was annotated to the KEGG database. EC: 1.1.1.49 (glucose-6-phosphate 1-dehydrogenase) and EC: 5.3.1.9 (glucose-6-phosphate isomerase), were found to play a potential role in glucose degradation and EC:2.7.1.4 (fructokinase) might be involved in the fructose metabolism. Growth profile and selenite-reducing ability of SR14 under different sugar supplements were determined and the results reviewed that glucose had a better promoting effect on the reduction of selenite and growth of bacteria than fructose, sucrose, and maltose. Moreover, RT-qPCR experiment proved that glucose supplement remarkably promoted the expressions of thioredoxin, fumarate reductase, and the glutathione peroxidase in SR14. Analysis of mRNA expression showed levels of glucose-6-phosphate dehydrogenase and fructokinase significantly upregulated under the supplement of glucose. Overall, our data demonstrated the genomic characteristics of SR14 and preliminarily determined that glucose supplement was most beneficial for strain growth and SeNPs synthesis.

3.
Food Chem ; 429: 136838, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37494755

RESUMEN

Aged white tea (WT) has promising medicinal potential, but how to accurately identify aged white tea is still a difficult problem. Inspired by tea cream, the relationship between the characteristics of nanoparticles in tea infusion and aging time was studied. The results showed that with the increase of aging time, the particle size of white tea nanoparticles (WTNs) decreased gradually. Microscopic images showed that the surface structure of WTNs was changed in three aspects: the waxy layer, the cuticle layer and the palisade tissue. Additional in vitro modeling demonstrated a strong correlation between nanoparticle size and protein and tea polyphenol content. The correlation between nanoparticle sizes and aging time was further verified in aged Pu'er raw tea. Starting with the tea infusion's nanoparticles, this study showed that the aging time of WT would impact the nanoparticles' properties, offering a unique way to determine the aging period of WT.


Asunto(s)
Nanopartículas , , Té/química , Alimentos , Polifenoles/análisis
4.
Polymers (Basel) ; 14(17)2022 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-36080599

RESUMEN

To provide a safe and effective supplement of the essential trace element selenium, we focused on the biosynthesis of nanoselenium (SeNPs) via probiotics. A novel kind of exopolymer-functionalized nanoselenium (SeEPS), whose average size was 67.0 ± 0.6 nm, was produced by Bacillus subtilis SR41, whereas the control consisted of exopolymers without selenium (EPS). Chemical composition analysis, Fourier transform infrared (FTIR) spectroscopy and high-performance liquid chromatography (HPLC) confirmed that SeEPS and EPS shared similar polysaccharide characteristic groups, such as COO- and C=O, and contained not only 45.2-45.4% of sugars but also 23.5-24.7% of proteins and some lipids. Both SeEPS and EPS were primarily composed of mannose, amino glucose, ribose, glucose and galactose. Furthermore, to identify the biologically active component of SeEPS, three kinds of selenium particles with different stabilizers [Se(0), bovine serum albumin-Se and EPS-Se] were synthesized chemically, and their ability to scavenge free radicals in vitro was compared with that of SeEPS and EPS. The results revealed that EPS itself exhibited weak superoxide and hydroxyl radical scavenging abilities. Nevertheless, SeEPS had superior antioxidant properties compared to all other products, possibly due to the specific structure of SeNPs and exopolymers. Our results suggested that exopolymer-functionalized SeNPs with specific monosaccharide composition and structure could eventually find a potential application as an antioxidant.

5.
J Microbiol Biotechnol ; 26(2): 364-72, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26502737

RESUMEN

Sand tubules, made up of sand grains cemented by microbe-induced calcium carbonate precipitation, have been found in China's Ningxia Province. Sand tubules grow like a tree's roots about 40-60 cm below the surface. The properties of sand tubules and their bacterial community were examined. X-Ray diffraction analysis revealed that the sand tubules were associated with crystalline calcite. Scanning electron microscopy showed that the crystalline solid had a lamellar structure and lacked the presence of cells, suggesting that no bacteria acted as nucleation sites, nor that the crystalline solid was formed by the aggregation of bacteria. Denaturing gradient gel electrophoresis analysis showed 11 of the 12 detectable bands were uncultured bacteria by BLAST analysis in the GenBank database, and the rest were closely related to Paenibacillus sp. (100% identity). By cultivation techniques, the only strain isolated from the sand tubule was suggested to be related to Paenibacillus sp.; no archaea were found. Furthermore, Paenibacillus sp. was demonstrated to induce calcium carbonate precipitation in vitro.


Asunto(s)
Carbonato de Calcio , Consorcios Microbianos , Paenibacillus/aislamiento & purificación , Dióxido de Silicio , Archaea , Bacterias , China , ADN Bacteriano , ADN Ribosómico , Electroforesis en Gel de Gradiente Desnaturalizante , Consorcios Microbianos/genética , Microscopía Electrónica de Rastreo , Paenibacillus/genética , ARN Ribosómico 16S , Difracción de Rayos X
6.
J Zhejiang Univ Sci B ; 6(8): 793-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16052713

RESUMEN

Three yearling lambs with a rumen cannula were used to investigate the effects of supplementation with an urea-minerals lick block (ULB) on the kinetics of ruminal fibre digestion, nutrient digestibility and nitrogen (N) utilization of rice straw (RS), ammonia bicarbonate (AB)treated RS (ABRS) and hay prepared from natural pasture. The digestibility of dry matter and organic matter of RS increased by 13.1% and 12.7% (P<0.05) when the diet was supplemented with ULB, and approached to that of ABRS, indicating that the effect of ULB on digestibility of RS is similar to that of AB treatment. The digestibility of ABRS was slightly improved by the ULB feeding. Nitrogen retention was highest in lambs fed on ABRS alone, followed by hay with ULB, and was lowest in animals fed on RS with ULB. However, both the amount and proportion of N retention to N intake were enhanced by ULB supplementation to lambs fed on hay. The proportion of N retained to N digested decreased due to ULB supplementation to lambs fed on RS or ABRS. Supplementing ULB did not greatly influence the rumen degradation of either dry matter or crude protein in each of the three diets. RS and hay had similar values in the potential extent of digestion (PED) and digestion rate of PED (kd) of fibrous materials, but the discrete lag time for RS was lower than that for hay. The AB treatment significantly increased the PED (P<0.05) and kd (P<0.05) of RS. Neither the PED nor kd for RS and ABRS was influenced by ULB supplementation, but the kd for hay significantly increased due to ULB. The lag time for hay was also shortened by the ULB feeding. The ULB improved the digestion of fibre in the rumen of lambs fed on low quality roughage. It is inferred that while ULB is effective in increasing nutrient digestibility of low quality roughages by improving ruminal fibre digestion. A synchronized supply of N and energy to rumen microbes should be considered to improve the efficiency of N utilization when the basal diet is ammoniated straw.


Asunto(s)
Alimentación Animal , Fibras de la Dieta/metabolismo , Suplementos Dietéticos , Digestión/fisiología , Conducta Alimentaria/fisiología , Ovinos/fisiología , Urea/administración & dosificación , Administración Oral , Animales , Digestión/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Minerales/administración & dosificación , Nitrógeno/metabolismo
7.
J Zhejiang Univ Sci B ; 6(8): 787-92, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16052712

RESUMEN

The effect of tea saponins (TS) on rumen fermentation and methane emission was examined using an in vitro gas production technique named Reading Pressure Technique. Three levels of TS addition (0, 0.2, 0.4 mg/ml) were evaluated in the faunated and defaunated rumen fluid. Compared to the control, TS addition decreased the 24 h gas production in the faunated rumen fluid, but had a minor effect on gas yield in the defaunated rumen fluid. The TS significantly reduced methane production in vitro. In the faunated rumen fluid, 0.2 or 0.4 mg/ml TS decreased the 24 h methane emission by 12.7% or 14.0%, respectively. Rumen fluid pH value was affected neither by TS addition nor by defaunation. The TS addition had only minor effects on volatile fatty acids, but the yield and pattern of volatile fatty acids were greatly affected by defaunation. While the molar proportion of acetate was not affected by defaunation, the propionate was significantly increased and the butyrate significantly decreased. Ammonia-N concentration and microbial protein yield were influenced by TS inclusion and defaunation. Inclusion of 0.4 mg/ml TS increased the microbial protein mass by 18.4% and 13.8% and decreased the ammonia-N concentration by 8.3% and 19.6% in the faunated and defaunated rumen fluid, respectively. Protozoa counts were significantly reduced by TS inclusion. The current study demonstrated the beneficial effect of TS on methane production and rumen fermentation, and indicated that this may be due to the effect of the associated depression on protozoa counts.


Asunto(s)
Camellia sinensis/metabolismo , Eucariontes/fisiología , Contenido Digestivo/efectos de los fármacos , Contenido Digestivo/microbiología , Metano/metabolismo , Rumen/metabolismo , Rumen/microbiología , Saponinas/farmacología , Animales , Eucariontes/efectos de los fármacos , Fermentación/efectos de los fármacos , Técnicas In Vitro , Extractos Vegetales/farmacología , Semillas/metabolismo , Ovinos , Té/química
8.
Wei Sheng Wu Xue Bao ; 45(1): 145-8, 2005 Feb.
Artículo en Zh | MEDLINE | ID: mdl-15847184

RESUMEN

Methanogens belong to the kingdom of Euryarchaeota in the domain of Archaea. They are characterized by their ability to produce methane under anaerobic conditions. Methane production in the rumen represents a loss of energy for the host animal, and, in addition, methane eructated by ruminants may contribute to a greenhouse effect or global warming. Reduction or elimination of methanogenesis in the rumen has been touted as a way of improving animal production and may marginally benefit to control of anthropogenic release of methane. More and more scientists focus on ruminal methanogens and methanogenesis recently. Authors summarized the manipulation of methanogenesis in the rumen, including defaunation, feed formulation, adding electron acceptors and stimulation of acetogens. The characteristics of methanogenic Archaea and the recent knowledge of the methanogenesis in the rumen were also reviewed in this article.


Asunto(s)
Euryarchaeota/metabolismo , Euryarchaeota/fisiología , Metano/metabolismo , Rumen/microbiología , Animales , Euryarchaeota/clasificación , Rumiantes
9.
Anticancer Res ; 22(2A): 633-8, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12014631

RESUMEN

When estrogen binds its receptor (ER), it becomes a potent mitogen in a number of target tissues including the mammary gland where it plays an important role in the pathogenesis of mammary carcinoma. Arsenic trioxide (AS2O3), a clinically effective agent against acute promyelocytic leukemia, has been shown to induce apoptosis in a variety of cancer cells in vitro. Here, we investigated the effects of AS2O3 on the growth of two ER-positive breast cancer cell lines, MCF7 and T47D in vitro. We found that higher doses of AS2O3 dramatically reduced the survival of these two breast cancer cell lines while lower doses of AS2O3 significantly inhibited the expression of estrogen receptor alpha (ER-alpha), but did not effect ER-beta expression. The ER-alpha expression is totally restored when AS2O3 is absent for 24 hours. Using a reporter gene controlled by ER, we further demonstrated that AS2O3 strongly-repressed 17beta-estradiol (E2) stimulated-transcriptional activation. Moreover, AS2O3 abolished transcriptional induction of the estrogen responsive gene pS2 mediated by E2. These results indicated that AS2O3 specifically inhibits expression and signaling pathway of the ER-alpha. We suggest that AS2O3 in combination with other methods might provide a novel therapeutic approach for ER-alpha-positive breast cancer.


Asunto(s)
Antineoplásicos/farmacología , Arsenicales/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Óxidos/farmacología , Receptores de Estrógenos/antagonistas & inhibidores , Trióxido de Arsénico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Muerte Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Receptor alfa de Estrógeno , Receptor beta de Estrógeno , Humanos , Biosíntesis de Proteínas , Proteínas/genética , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/genética , Receptores de Estrógenos/fisiología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Activación Transcripcional/efectos de los fármacos , Activación Transcripcional/fisiología , Factor Trefoil-1 , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor
10.
Int J Biol Macromol ; 49(4): 466-70, 2011 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-21664928

RESUMEN

The extraction conditions of polysaccharides from Plantago asiatica L. seeds were investigated. Four parameters affecting the polysaccharides extraction, extraction times, water to sample, extraction temperature and single extraction time, were determined by orthogonal experiments. Under the optimized conditions, the polysaccharides yield of P. asiatica L. seeds was 2.467%. The antioxidant activities of the polysaccharides were investigated. The reducing power of the polysaccharides was dose dependent, and the reducing capacity of the polysaccharides was inferior to butylated hydroxytoluene, which is known to be a strong reducing agent. The scavenging rates of the polysaccharides on superoxide and 1,1-diphenyl-2-picrylhydrazyl radicals were 79.7% and 81.4%, at polysaccharides concentration of 0.75 mg/mL, respectively, a scavenging rates approximately similar to that of 0.75 mg/mL ascorbic acid (83.5% and 85.1%, respectively). Furthermore, it exhibited a moderate concentration-dependent ABTS radical scavenging activity, ferrous ion chelating potency and H(2)O(2) scavenging activity. The data obtained in the in vitro models clearly establish the antioxidant potency of the polysaccharides extracted from Semen Plantaginis.


Asunto(s)
Antioxidantes/farmacología , Plantago/química , Polisacáridos/aislamiento & purificación , Polisacáridos/farmacología , Semillas/química , Ácido Ascórbico/farmacología , Benzotiazoles/metabolismo , Compuestos de Bifenilo/metabolismo , Hidroxitolueno Butilado/metabolismo , Quelantes/farmacología , Fraccionamiento Químico , Ácido Edético/farmacología , Depuradores de Radicales Libres/farmacología , Peróxido de Hidrógeno/metabolismo , Oxidación-Reducción/efectos de los fármacos , Picratos/metabolismo , Ácidos Sulfónicos/metabolismo , Superóxidos/metabolismo
11.
Arch Anim Nutr ; 60(1): 89-97, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16529160

RESUMEN

Two experiments were conducted to investigate the effects of tea saponins (TS) on in vitro ruminal fermentation and growth performance in growing Boer goats. In Experiment 1, the Reading Pressure Technique (RPT) system was used to investigate the effect of addition of TS (0, 0.2, 0.4 and 0.8 mg/ml) on the ruminal fermentation in vitro. The 24h gas production and methane emission were significantly decreased when 0.4 or 0.8mg TS was included, suggesting that the TS could inhibit the release of methane. Compared to the control, the TS had little effect on pH values and the concentration of total volatile fatty acids in the ruminal fluids. However, the fermentation patterns were changed, with lower acetate and higher proportions of propionate when TS was added. Ammonia-N concentration and protozoal counts were significantly reduced, while microbial protein yield was increased by the TS addition, suggesting that the TS could modify the ruminal fermentation. In Experiment 2, 27 growing Boer goats were used to evaluate the effects of the TS addition on growth performance. The animals received the same basal diets, and added TS at levels of 0 (C), 3 g (T1) and 6 g (T2) per day. The experiment lasted for 60 days with the first 15 days for adaptation. Blood samples were obtained by jugular venipuncture before the morning feeding on the final day of the experiment. During the whole periods, dry matter intake, average daily gain and feed efficiency in T1 were higher than in the other two. Serum total protein, albumin, high density lipoprotein cholesterol, Ca and P and alkaline phosphatase levels were higher in group T1 than in C and T2, whereas the blood urea nitrogen, creatinine and total cholesterol were lower in the TS-added groups. The concentrations of glucose, glutamic-oxaloacetic transaminase and glutamic-pyruvic transaminase were not affected by the TS. From the results obtained in this study, it is inferred that the TS could modify the ruminal fermentation and that proper doses of TS may have potential in improving the animal growth performance, whereas at high doses, it may have adverse effects on animal production.


Asunto(s)
Cabras/crecimiento & desarrollo , Rumen/efectos de los fármacos , Saponinas/farmacología , Té/química , Animales , Análisis Químico de la Sangre/veterinaria , Relación Dosis-Respuesta a Droga , Eucariontes/crecimiento & desarrollo , Ácidos Grasos Volátiles/análisis , Ácidos Grasos Volátiles/metabolismo , Femenino , Fermentación , Cabras/metabolismo , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Masculino , Rumen/metabolismo , Rumen/microbiología , Rumen/parasitología , Saponinas/efectos adversos , Factores de Tiempo
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