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1.
J Dairy Sci ; 107(7): 4161-4173, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38246556

RESUMO

Whey protein isolate (WPI)-based nanodelivery systems have recently attracted an increasing amount of attention. Despite this, research focusing on milk protein concentrate (MPC) and micellar casein (MCC) as carriers loaded in hydrophobic compounds is lacking. This study investigated the mediated effect of docosahexaenoic acid (DHA) in 3 different milk proteins for the embedding of astaxanthin (ASTA) after ultrasound-assisted pH-shifting treatment. We then evaluated the application of milk protein carriers in cheese processing by comparing MPC, MCC, and WPI. The particle size, polydispersity index, and zeta potential results of the milk protein-DHA complex suggested that the addition of 0.36 µmol/mL DHA optimized the delivery of milk protein to ASTA. All 3 DHA-mediated milk proteins induced an improvement in encapsulation efficiency and antioxidant properties of ASTA. Furthermore, the DHA-mediated MPC and MCC played a stronger role in improving the bioaccessibility and thermal and storage stability of ASTA than those without DHA. Tests conducted to examine the application in cheese production indicated that MCC carrier had a positive effect on the texture of cheeses. However, the delivery effect was dependent on the milk protein variety, and MCC exhibited the best protection ability of ASTA, followed by MPC and WPI. The simulated digestion and storage stability results of cheese further confirmed that the protein encapsulation mediated by DHA was more conducive to ASTA absorption. These findings suggested that the DHA-mediated milk protein complexes studied here may be suitable hydrophilic delivery carriers for the hydrophobic nutrient ASTA, potentially playing different roles in improving its storage stability and bioaccessibility.


Assuntos
Queijo , Ácidos Docosa-Hexaenoicos , Proteínas do Leite , Xantofilas , Animais , Concentração de Íons de Hidrogênio , Proteínas do Soro do Leite , Caseínas
2.
J Sci Food Agric ; 103(5): 2631-2640, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36494899

RESUMO

BACKGROUND: Branched-chain fatty acid (BCFA) is effective in preventing and helping to treat neonatal necrotizing enterocolitis. It is essential to supplement goat-milk powder for formula-fed preterm infants with BCFA. In this study, the quality and microstructures of milk powders supplemented with different concentrations of BCFA were evaluated, using goat milk powder without BCFA as the control group (CG). RESULTS: In comparison with the CG, goat milk powder supplemented with BCFA exhibited smaller fat globules and a significant drop in overall particle size. During 16 weeks of storage, BCFA-supplemented groups showed suitable moisture content and viscosity and good solubility. The BCFA also helped reduce the number of folds on the surface of the milk powder particles. CONCLUSION: The findings of this study indicate that goat milk powders with BCFA exhibit differences in quality and microstructure in comparison with ordinary goat milk powder, which is relevant for the future development and application of BCFA in foods. © 2022 Society of Chemical Industry.


Assuntos
Cabras , Leite , Recém-Nascido , Animais , Humanos , Leite/química , Pós/análise , Recém-Nascido Prematuro , Ácidos Graxos/química
3.
J Dairy Sci ; 103(2): 1289-1302, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31837775

RESUMO

This work investigated the effects of thermal processing methods commonly used in the dairy industry and prolonged treatment at different temperatures on the denaturation, microstructure, and functional properties of whey proteins (WP) from goat milk. The complete denaturation of WP was observed in goat milk treated at 85°C for 30 min, and at a higher temperature (>85°C), a considerable amount of WP was easily denatured. The low temperature, long time treatment had the least effect on the secondary structure, whereas ultra-high temperature treatment had the greatest effect, and the amount of regular structures decreased gradually with prolonged time. The most serious morphological damage occurred after treatment at 85°C for 30 min, which was consistent with the denaturation results. This result indicated that the denaturation degree, particle size, surface hydrophobicity, and microstructure had a strong influence on the functional properties of WP from goat milk after heat treatment. The heat treatment of goat milk at 65°C for 30 min and 85°C for 15 s increased the particle size, turbidity, zeta potential, and surface hydrophobicity of WP, and these increases ensured that the WP had a good emulsifying activity index, water-holding capacity, oil-holding capacity, foaming capacity, and foam stability. This study simulated the heat treatment conditions used in actual production, aiming to provide a theoretical basis for industry.


Assuntos
Cabras , Calefação , Leite/química , Proteínas do Soro do Leite/química , Animais , Feminino , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Conformação Proteica , Desnaturação Proteica
4.
Bioorg Med Chem ; 24(2): 270-6, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26712097

RESUMO

A series of new cobalt(III) complexes were prepared. They are [CoL(1)(py)3]·NO3 (1), [CoL(2)(bipy)(N3)]·CH3OH (2), [CoL(3)(HL(3))(N3)]·NO3 (3), and [CoL(4)(MeOH)(N3)] (4), where L(1), L(2), L(3) and L(4) are the deprotonated form of N'-(2-hydroxy-5-methoxybenzylidene)-3-methylbenzohydrazide, N'-(2-hydroxybenzylidene)-3-hydroxylbenzohydrazide, 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol, and N,N'-bis(5-methylsalicylidene)-o-phenylenediamine, respectively, py is pyridine, and bipy is 2,2'-bipyridine. The complexes were characterized by infrared and UV-Vis spectra, and single crystal X-ray diffraction. The Co atoms in the complexes are in octahedral coordination. Complexes 1 and 4 show effective urease inhibitory activities, with IC50 values of 4.27 and 0.35 µmol L(-1), respectively. Complex 2 has medium activity against urease, with IC50 value of 68.7 µmol L(-1). While complex 3 has no activity against urease. Molecular docking study of the complexes with Helicobacter pylori urease was performed.


Assuntos
Cobalto/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Compostos Organometálicos/farmacologia , Urease/antagonistas & inibidores , Cobalto/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Helicobacter pylori/enzimologia , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Bases de Schiff/química , Bases de Schiff/farmacologia , Relação Estrutura-Atividade , Urease/metabolismo
5.
J Sci Food Agric ; 96(9): 3169-72, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26459925

RESUMO

BACKGROUND: To evaluate the large quantities of genetically modified soybeans that are imported into China, we evaluated the presence of transgenes in soybean samples from an area, which are major soybean-producing areas. We evaluated the presence of exogenous genes in a total of 254 soybean samples from farms and 35 commercially available soybean samples using polymerase chain reaction amplification and sequence analysis. RESULTS: The farm soybean samples contained a total of 67 CaMV35S-positive samples, 46 NOS-positive samples, 16 CP4-EPEPS-positive samples, and 66 BT-positive samples. The commercially available soybean samples contained a total of 12 CaMV35S-positive samples, 19 NOS-positive samples, 13 CP4-EPEPS-positive samples, and 15 BT-positive samples. CONCLUSION: Several exogenous genes were detected in the farmed and commercially available soybeans. We should use caution in the management of genetically modified soybeans. © 2015 Society of Chemical Industry.


Assuntos
Glycine max/genética , Plantas Geneticamente Modificadas/genética , Agricultura , Sequência de Bases , China , DNA de Plantas/análise , DNA de Plantas/genética , Alimentos Geneticamente Modificados , Folhas de Planta/genética , Proteínas de Plantas/análise , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase/métodos , Análise de Sequência
6.
Int J Gynecol Cancer ; 25(8): 1338-44, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26111274

RESUMO

OBJECTIVE: Studies investigating the association between BRCA2 Arg372His polymorphism and ovarian cancer risks have yielded conflicting results. METHODS: We carried out a meta-analysis of 8488 ovarian cancer cases and 14,510 controls from 7 case-control studies in 5 articles published. The association between BRCA2 Arg372His polymorphism and ovarian cancer susceptibility was calculated using pooled odds ratios (ORs) appropriately derived from fixed effects models. RESULTS: There were no significant associations between BRCA2 Arg372His polymorphisms and ovarian cancer risk in overall comparisons in all genetic models (HH vs NN: OR, 1.06; 95% confidence interval [95% CI], 0.96-1.18; P = 0.25; NH vs NN: OR, 1.02; 95% CI, 0.96-1.07; P = 0.6; NH + HH vs NN: OR, 1.01; 95% CI, 0.98-1.04; P = 0.42; HH vs NN + NH: OR, 1.06; 95% CI, 0.95-1.17; P = 0.29). CONCLUSIONS: This meta-analysis indicates that the BRCA2 Arg372His polymorphism is not associated with ovarian cancer risk for whites. Asian and African populations should be further studied.


Assuntos
Proteína BRCA2/genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Feminino , Humanos , Prognóstico , Fatores de Risco
7.
Int J Biol Macromol ; 259(Pt 1): 129148, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176483

RESUMO

This study explored the improvement of casein (CN)'s properties by conjugating it with oligosaccharides, namely, fructooligosaccharide (FOS), galactooligosaccharide (GOS), isomaltooligosaccharide (IMO), and xylo-oligosaccharide (XOS) via Maillard reaction to identify the most optimal oligosaccharides and modification conditions. The degree of grafting was 30.5 ± 0.41 % for CN-FOS, 33.7 ± 0.62 % for CN-GOS, 38.9 ± 0.51 % for CN-IMO, and 43.7 ± 0.54 % for CN-XOS. With the degree of grafting rising, more oligosaccharides were conjugated, causing greater changes in CN properties. The CN-XOS underwent significant alterations, as the introduction of oligosaccharides led to a decrease in particle size by around 51 nm. Furthermore, the hydroxyl groups caused a reduction in surface hydrophobicity, which in turn decreased the proportion of hydrophobic groups. The solubility of CN-XOS increased significantly at pH 3, by approximately 30.99 %. Additionally, the conjugation of oligosaccharides substantially boosted the rates of DPPH, ABTS, and -OH radical scavenging by 4.61 times, 2.20 times, and 2.58 times, respectively, and also improved the thermal stability of the modified CN. Moreover, the process lowered the protein digestibility, possibly enhancing its applicability as an active substance transporter. This research offers additional theoretical backing for altering CN with oligosaccharides and implementing it in the food and pharmaceutical sectors.


Assuntos
Caseínas , Reação de Maillard , Solubilidade , Oligossacarídeos/química , Antígenos
8.
Mol Biol Rep ; 40(10): 6001-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24057181

RESUMO

Results conflict on the association between progesterone receptor gene (PRG) polymorphism PROGINS and ovarian cancer risk, despite wide-ranging investigations. We therefore performed a meta-analysis of 4,285 ovarian cancer cases and 6,257 controls from 11 published case-control studies. The strength of association between PROGINS polymorphism and ovarian cancer susceptibility was assessed using pooled odds ratios (ORs) with corresponding 95 % confidence intervals (CIs). The results suggest no significant associations exist between PROGINS polymorphisms and ovarian cancer risk in overall comparisons in all genetic models (T2T2 vs. T1T1: OR = 1.37, 95 % CI = 0.89-2.12, P = 0.15; T1T2 vs. T1T1:OR = 1.09, 95 % CI = 0.88-1.35, P = 0.41; T1T2 + T2T2 vs. T1T1:OR = 1.15, 95 % CI = 0.94-1.40, P = 0.17; T2T2 vs. T1 T1 + T1T2:OR = 1.34, 95 % CI = 0.87-2.07, P = 0.18). In conclusion, the results of this meta-analysis indicate that the PRG polymorphism PROGINS is not associated with ovarian cancer risk when multiple ethnic groups or regions were considered overall.


Assuntos
Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Polimorfismo Genético , Receptores de Progesterona/genética , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Humanos , Modelos Genéticos , Viés de Publicação , Fatores de Risco
9.
Artigo em Inglês | MEDLINE | ID: mdl-36767813

RESUMO

Graphene oxide (GO) has good dispersibility and adsorption capacity for antibiotics adsorption, a complex process influenced by many factors. In this work, the adsorption mechanism of GO on tetracycline antibiotics at different pH was studied to address its attenuated effects on the microbial growth. The results showed that the adsorption process of GO on three antibiotics, namely, tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC), followed the pseudo-second-order kinetic model. The maximum adsorption capacities were observed at pH5 which were 133.0 mg/g for TC, 125.4 mg/g for OTC, and 167.0 mg/g for CTC. Furthermore, the reaction was uniform adsorption with a single layer on the surface of GO, and heating was conducive to the reaction. In the microbial growth experiment, the growth of E. coli and B. subtilis senses was optimal at pH5, which was consistent with the adsorption experiment. This study analyzed the effect of pH on the adsorption of antibiotics by GO and provided a theoretical basis for the further application of GO in various aquatic environments.


Assuntos
Clortetraciclina , Oxitetraciclina , Poluentes Químicos da Água , Adsorção , Escherichia coli , Antibacterianos , Tetraciclina , Concentração de Íons de Hidrogênio
10.
Foods ; 12(17)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37685089

RESUMO

Cherry tomatoes are easily damaged due to their high moisture content. A composite coating was developed to delay deterioration and prolong storage by mixing antibacterial sulfated rice bran polysaccharides (SRBP) and edible hydroxyethyl cellulose (HEC) with film-forming properties. The effects of HEC, HEC-5% SRBP, and HEC-20% SRBP preservative coatings on the maintenance of the quality of cherry tomatoes (LycopersivonesculentumMill., Xiaohuang F2) during cold storage were investigated. The HEC-20% SRBP coating significantly reduced tomato deterioration and weight loss, delayed firmness loss, decreased polyphenol oxidase activity, and increased peroxidase activity. Furthermore, cherry tomatoes treated with HEC-20% SRBP maintained high levels of titratable acid, ascorbic acid, total phenols, and carotenoids. Cherry tomatoes coated with HEC-SRBP also had higher levels of volatile substances and a greater variety of these substances compared to uncoated tomatoes. In conclusion, the HEC-20% SRBP coating effectively delayed deterioration and preserved cherry tomatoes' nutrient and flavor qualities during postharvest cold storage, suggesting it could be a novel food preservation method.

11.
Ultrason Sonochem ; 88: 106089, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35809472

RESUMO

This study investigated the effects of different treatment of alkaline pH-shifting on milk protein concentrate (MPC), micellar casein concentrate (MCC) and whey protein isolate (WPI) assisted by the same ultrasound conditions, including changes in the physicochemical properties, solubility and foaming capacity. The solubility of milk proteins had a significant increase with gradual enhancement of ultrasound-assisted alkaline pH-shifting (p < 0.05), especially for MCC up to 99.50 %. Also, treatment made a significant decline in the particle size of MPC and MCC, as well as the turbidity of the proteins (p < 0.05). The foaming capacity of MPC, MCC, and WPI was all improved, especially at pH 11, and at this pH, the milk protein also showed the highest surface hydrophobicity. The best foaming capacity at pH 11 was the result of the combined effect of particle size, potential, protein conformation, solubility, and surface hydrophobicity. In conclusion, ultrasound-assisted pH-shifting treatment was found to be effective in improving the physicochemical properties and solubility and foaming capacity of milk proteins, especially MCC, with promising application prospect in food industry.


Assuntos
Caseínas , Proteínas do Leite , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Micelas , Proteínas do Leite/química , Solubilidade , Proteínas do Soro do Leite/química
12.
Food Sci Anim Resour ; 42(5): 800-815, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36133637

RESUMO

This study aimed to obtain high Fischer's ratio oligopeptides from goat whey (HFO) and investigate antioxidant property of it. Hydrolysis of goat whey was done with the approach of sequential digestion of pepsin and flavourzyme. With the adsorption of aromatic amino acids by activated carbon, HFO with a Fischer's ratio of 27.070 and a molecular weight of 200-1,000 Da were obtained, and the branched-chain amino acids accounted for 22.87%. Then the antioxidant activity of HFO was evaluated. At the concentrations of 2.0 mg/mL and 0.50 mg/mL, HFO scavenged 77.27% and 99.63% of 1,1-diphenyl-2-picrylhydrazyl and 3-ethylbenzthiazoline-6-sulphonate free radicals respectively. The scavenging rate of HFO against hydroxyl radicals reached 92.31% at the concentration of 0.25 mg/mL. Animal experiments demonstrated that HFO could moderate the changes of malondialdehyde, superoxide dismutase and glutathione peroxidase caused by CCl4-induced oxidative stress in vivo. This study indicated that HFO from goat whey was capable of oxidation resistance both in vivo and in vitro, which provided a scientific basis for the high-value processing and application of goat milk whey.

13.
Acta Pharm Sin B ; 11(7): 1867-1884, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34386325

RESUMO

Blood-brain barrier (BBB) damage after ischemia significantly influences stroke outcome. Compound LFHP-1c was previously discovered with neuroprotective role in stroke model, but its mechanism of action on protection of BBB disruption after stroke remains unknown. Here, we show that LFHP-1c, as a direct PGAM5 inhibitor, prevented BBB disruption after transient middle cerebral artery occlusion (tMCAO) in rats. Mechanistically, LFHP-1c binding with endothelial PGAM5 not only inhibited the PGAM5 phosphatase activity, but also reduced the interaction of PGAM5 with NRF2, which facilitated nuclear translocation of NRF2 to prevent BBB disruption from ischemia. Furthermore, LFHP-1c administration by targeting PGAM5 shows a trend toward reduced infarct volume, brain edema and neurological deficits in nonhuman primate Macaca fascicularis model with tMCAO. Thus, our study identifies compound LFHP-1c as a firstly direct PGAM5 inhibitor showing amelioration of ischemia-induced BBB disruption in vitro and in vivo, and provides a potentially therapeutics for brain ischemic stroke.

14.
RSC Adv ; 10(52): 31027-31038, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-35520650

RESUMO

Anti-agglomerants (AAs), both natural and commercial, are currently being considered for gas hydrate risk management of petroleum pipelines in offshore operations. However, the molecular mechanisms of the interaction between the AAs and gas hydrate surfaces and the prevention of hydrate agglomeration remain critical and complex questions that need to be addressed to advance this technology. Here, we use molecular dynamics (MD) simulations to investigate the effect of model surfactant molecules (polynuclear aromatic carboxylic acids) on the agglomeration behaviour of gas hydrate particles and disruption of the capillary liquid bridge between hydrate particles. The results show that the anti-agglomeration pathway can be divided into two processes: the spontaneous adsorption effect of surfactant molecules onto the hydrate surface and the weakening effect of the intensity of the liquid bridge between attracted hydrate particles. The MD simulation results also indicate that the anti-agglomeration effectiveness of surfactants is determined by the intrinsic nature of their molecular functional groups. Additionally, we find that surfactant molecules can affect hydrate growth, which decreases hydrate particle size and correspondingly lower the risk of hydrate agglomeration. This study provides molecular-level insights into the anti-agglomeration mechanism of surfactant molecules, which can aid in the ultimate application of natural or commercial AAs with optimal anti-agglomeration properties.

15.
PLoS One ; 14(9): e0222757, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31545823

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, and is the most common type of cognitive impairment and dementia. There is a pressing need to improve the clinical efficacy and quality of life for AD patients, as limited treatments options for AD patients have been developed until now. In this study, we aim to investigate the protective effect of CH(II), a cerebroprotein hydrolysate consisted of abundant biological peptides, on preclinical model of AD. We found that CH(II) treatment effectively protects oxygen glucose deprivation (OGD)-induced N2A cell viability impairment and cell apoptosis. In addition, CH(II) significantly reduces H2O2-induced ROS accumulation and exhibits the protective activities against H2O2-induced oxidative injury. Intriguingly, we found that CH(II) treatment can effectively promote neurite outgrowth of N2A cells. Moreover, CH(II) obviously improve the cognitive and memorial function in scopolamine-induced amnesia mice model. Taken together, this study provides evidences of the neuroprotective activities of CH(II) and offers a potential therapeutic strategy for AD patients.


Assuntos
Doença de Alzheimer/fisiopatologia , Cognição/efeitos dos fármacos , Modelos Animais de Doenças , Espaço Intracelular/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cognição/fisiologia , Feminino , Glucose/metabolismo , Glucose/farmacologia , Peróxido de Hidrogênio/farmacologia , Espaço Intracelular/metabolismo , Camundongos Endogâmicos C57BL , Neurogênese/efeitos dos fármacos , Oxidantes/farmacologia , Oxigênio/metabolismo , Oxigênio/farmacologia
16.
Food Chem ; 275: 504-514, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30724227

RESUMO

Milk proteins have shown to be very sensitive to heated processing. This study investigated the heat-dependent changes of goat milk proteins using label-free quantification (LFQ). A total of 843 proteins were identified in all the samples, of which 625 proteins were quantified. There were 527, 543, 537, 533 and 539 proteins quantified in the control group (CG) and heated groups (HGs: HG1, HG2, HG3 and HG4), respectively, and 438 proteins were common to all groups. The effects of high temperature/short time (HTST) treatment on proteins were similar to ultra-pasteurization (UP) and ultra-high temperature (UHT), but the low temperature/long time (LTLT) was different. Proteomics analysis demonstrated that heated processing increases the digestibility of proteins and is beneficial for anti-atherosclerosis therapy. These results expand the knowledge of the protein compositions from different heated processing. And it can further the utilization of the protein component of goat milk for human nutrition and health.


Assuntos
Manipulação de Alimentos , Temperatura Alta , Leite/metabolismo , Proteômica , Animais , Cabras , Pasteurização
17.
Anim Sci J ; 89(5): 794-801, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29349891

RESUMO

Taking fresh goat milk as raw material after filtering, centrifuging, hollow fiber ultrafiltration, allocating formula, value detection and preparation processing, a set of 10 goat milk mixed standard substances was prepared on the basis of one-factor-at-a-time using a uniform design method, and its accuracy, uniformity and stability were evaluated by paired t-test and F-test of one-way analysis of variance. The results showed that three milk composition contents of these standard products were independent of each other, and the preparation using the quasi-level design method, and without emulsifier was the best program. Compared with detection value by cow milk standards for calibration fast analyzer, the calibration by goat milk mixed standard was more applicable to rapid detection of goat milk composition, detection value was more accurate and the deviation showed less error. Single factor analysis of variance showed that the uniformity and stability of the mixed standard substance were better; it could be stored for 15 days at 4°C. The uniformity and stability of the in-units and inter-units could meet the requirements of the preparation of national standard products.


Assuntos
Laticínios/análise , Análise de Alimentos/métodos , Leite/química , Animais , Indústria de Laticínios , Cabras , Ultrafiltração
18.
Anim Sci J ; 89(11): 1628-1638, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30191634

RESUMO

The objective of this study was to characterize the variations in fatty acid (FA) profile during 7 days of colostrum production and 5 months of mature milk production in Laoshan goats. The individual FA profiles of each sample were investigated by gas chromatography-mass spectrometry. Significant differences in FAs were found between colostrum and mature milk. The contents of saturated fatty acids (SFA), unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA), and sum of C6, C8, and C10 (SC6+C8+C10 ) were all significantly affected by lactation period. Furthermore, there was no significant difference in the ratio of UFA/SFA or C18:2 (cis9, cis12-octadecadienoic acid)/C18:3 (all cis-9,12,15-octadecatrienoic acid) during the lactation period. The highest concentrations of SC6+C8+C10 , UFA, MUFA, and PUFA appeared in colostrum, but the highest SFA content was in mature milk. The highest proportions of SC6+C8+C10 and SFA were 11.32% and 79.55% on 5th day and 135th day respectively. By contrast, the lowest proportion of UFA was 20.45% on the 135th day. C14:0 (10.93%-12.87%), C16:0 (27.54%-36.65%), C18:0 (10.47%-14.59%), and C18:1 (18.80%-30.61%) were the most predominant FAs in goat milk with significant differences during the 135 days lactation period except C18:0. In conclusion, the results of this study suggest that the lactation time has a pronounced effect on the FA compositions of goat milk.


Assuntos
Colostro/química , Ácidos Graxos/análise , Cabras/metabolismo , Cabras/fisiologia , Lactação/metabolismo , Leite/química , Parto/fisiologia , Período Pós-Parto/fisiologia , Animais , Ácidos Graxos Monoinsaturados/análise , Ácidos Graxos Insaturados/análise , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Lactação/fisiologia , Fatores de Tempo
19.
Anim Sci J ; 89(9): 1355-1363, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29956422

RESUMO

Despite the global increasing demand for goat milk, no data exist on the nutrient potential of Laoshan goat milk and limited information exists on its composition according to lactation period. In this study, the measured indicators, including dry matter, protein, immunoglobulin, lactoferrin, fat, ash, lactose, calcium, titratable acidity and pH from partum to 261 days postpartum of Laoshan goat milk, followed the same law of change. There was a significant difference over the first 5 days postpartum, after which no significant difference was observed until days 225 postpartum. However, days 255 postpartum was like a turning point, after which their values showed either an increasing or decreasing trend. We concluded that the colostrum for Laoshan dairy goat was considered from days 1 to 5 postpartum and after 5 days it was as transitioned to milk when all measured parameters were according to the normal ranges as described in this study. This work provided updated information on the current nutritive characteristics of Laoshan goat milk, which may be of importance in the fields of milk production, food technology, and nutritional mutual replenishment.


Assuntos
Cabras/metabolismo , Lactação/metabolismo , Leite/química , Leite/metabolismo , Período Pós-Parto/metabolismo , Animais , Cálcio/análise , Indústria de Laticínios , Gorduras/análise , Feminino , Tecnologia de Alimentos , Concentração de Íons de Hidrogênio , Imunoglobulinas/análise , Lactoferrina/análise , Lactose/análise , Proteínas do Leite/análise , Fatores de Tempo
20.
Sci China C Life Sci ; 50(3): 335-42, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17609890

RESUMO

Four single-nucleotide polymorphisms (SNP) of the Phosphoglyceric Kinase (PGK) gene were discovered based on comparison of the sequences from an altiplano chicken breed (Tibetan chicken) and two lowland breeds (White Leghorn and Shouguang chicken). Gel-shift results indicate that one of these SNPs, an A-->G mutation at position 59 in exon10, is able to bind hypoxia-induced factor-l (HIF-1), functioning as a hypoxia response element (HRE). The mutant gene results in M-->T mutation at position 379 amino acid. The combined activity of this HRE and HIF-1 could increase correspondingly under a hypoxic stimulus. Hypoxia leads to increased death rates of chicken embryos; while the M-->T mutation described herein is prevalent in healthy embryos grown under hypoxic conditions, thus it may represent an adaptation to hypoxia. Fluorescence quantitative reverse transcription PCR results revealed that HIF-1 upregulates the transcript level of the glycolytic enzyme PGK in the brain and skeletal muscle of animals subjected to hypoxia. Thus, a large amount of ATP is produced by increased glycolysis, allowing the organism to meet energy metabolism demands. As such, we believe this SNP to be an adaptation to the external anoxic environment.


Assuntos
Galinhas/genética , Regulação Enzimológica da Expressão Gênica , Hipóxia/enzimologia , Músculo Esquelético/enzimologia , Fosfoglicerato Quinase/genética , Polimorfismo de Nucleotídeo Único , Animais , Núcleo Celular/enzimologia , Embrião de Galinha , Galinhas/classificação , Galinhas/crescimento & desenvolvimento , Primers do DNA , Hipóxia/genética , Análise dos Mínimos Quadrados , Reação em Cadeia da Polimerase , Transcrição Gênica
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