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1.
Food Chem ; 336: 127689, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763736

RESUMO

Milk oxidases are an integral part of milk immune system, and good indicators for milk thermal history. Current assay methods for milk oxidases are either insensitive, tedious or not cost-effective. In this study, a high-throughput fluorescence assay method for determination of xanthine oxidase (XO) and polyamine oxidase (PAO) activities in milk samples was developed. The hydrogen peroxide generated by XO catalysed oxidation of hypoxanthine, and PAO catalysed oxidation of spermine, was coupled to horseradish peroxidase conversion of Amplex® Red (1-(3,7-dihydroxyphenoxazin-10-yl)ethanone) to the fluorescent product resorufin. The assay was highly sensitive, with limits of detection of activity in milk being 3 × 10-7 and 7 × 10-7 U/mL for XO and PAO, respectively. Intra-run and inter-run results showed good assay repeatability and reproducibility. The assay was successfully applied to survey the XO and PAO activities in human, bovine, goat and camel milk samples, and it can be readily adapted for measurements of other oxidase activities.


Assuntos
Ensaios Enzimáticos/métodos , Leite/enzimologia , Oxirredutases/metabolismo , Animais , Biocatálise , Camelus , Bovinos , Cabras , Humanos , Peróxido de Hidrogênio/metabolismo , Hipoxantina/metabolismo , Limite de Detecção , Oxazinas/metabolismo , Oxirredução , Espectrometria de Fluorescência
2.
Food Chem ; 336: 127699, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768905

RESUMO

Cheese is one of the most widely consumed food products in the world. However, the increasing demand for nutritionally enhanced or functional products by the cheese industry has created new approaches that partially or fully replace milk fat. With this, new methods of adulteration have also been noted, potentially leading to these fully/partially-replaced products being offered as cheese. In this study, Raman spectroscopy was used to determine origins of fats in margarine, corn, and palm oils present in white and ultra-filtered cheese samples. Raman spectra were evaluated with partial least square-discriminant (PLS-DA) and PLS to identify fat/oil origins and adulteration ratios. The coefficients of determination and limits of detection for margarine, and corn and palm oil adulteration were found to be 0.990, 0.993, 0.991 and 3.38%, 3.36% and 3.59%, respectively.


Assuntos
Queijo/análise , Análise de Dados , Gorduras/análise , Análise de Alimentos/métodos , Leite/química , Análise Espectral Raman , Ultrafiltração , Animais , Contaminação de Alimentos/análise , Análise dos Mínimos Quadrados , Análise Multivariada
3.
Food Chem ; 334: 127555, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711268

RESUMO

Conjugated linoleic acid (CLA) content of ruminant milk reported in published research papers (n = 65) from January 1995 to March 2020 around the world were analyzed to estimate the overall mean CLA value. The CLA content of ruminant milk samples was grouped according to geographical regions (Europe, South America, North America, Oceania, Asia, and Africa). The total CLA content of milk samples from cows, sheep, goats, yaks, and llama retrieved from the collected data ranged between 0.06 and 2.96% of total fatty acids. There is a wide variation of pooled estimated mean content of CLA in milk among the study regions and were highest in Oceania with 1.33% (95% confidence interval (CI): 1.16 - 1.49%) of total fatty acids. Though several factors have been reported to influence the CLA content of milk, the effect of the "geographical origin" was only considered in the present manuscript as one of the main factors in this respect.


Assuntos
Ácidos Linoleicos Conjugados/análise , Leite/química , África , Animais , Ásia , Bovinos , Europa (Continente) , Ácidos Graxos/análise , Cabras , América do Norte , Oceania , Ruminantes , Ovinos , América do Sul
4.
Food Chem ; 334: 127559, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711270

RESUMO

This study approaches the development of a method for the determination of Ca, Mg, Zn, and Fe in liquid and powdered cow milk. The method is based on sample dissolution assisted by ultrasound energy in tetramethylammonium hydroxide (TMAH) media and determination by flame atomic absorption spectrometry (FAAS). Central composite design (CCD) associated with response surface methodology and desirability function allowed the fast and efficient optimization of the variables involved in the performance of the dissolution. The developed dissolution method allowed Ca, Fe, Zn, and Mg determination in milk samples with adequate analytical characteristics for these determinations. Addition/recovery tests and analysis of a certified reference material of skimmed powdered milk (ERM-BD150) have shown that this method presents enough accuracy to carry out these analyses.


Assuntos
Análise de Alimentos/métodos , Metais/análise , Leite/química , Compostos de Amônio Quaternário/química , Espectrofotometria Atômica/métodos , Animais , Bovinos , Feminino , Análise de Alimentos/estatística & dados numéricos , Análise Multivariada , Pós , Solubilidade
5.
Food Chem ; 334: 127436, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711262

RESUMO

Milk samples (150 cow and 217 camel milk samples) were analyzed for protein, fat, lactose and total solids by near and mid-infrared transmission spectroscopy. Excellent positive correlations between the two methods were obtained for both types of milk (p < 0.001); for protein (r ≥ 0.96), fat (r ≥ 0.99), lactose (r = 0.82) and total solids (r = 0.90). The mean of the relative difference ((MIR values - NIR values)/0.5 (MIR values + NIR values) × 100%) for cow and camel milk were, for protein (+8.2 & +13.4%), fat (-9.3 & +0.9%), lactose (-5.4 &-0.7%) and total solids (-2.2 &-3.4%), respectively. The difference between the two methods may be due to the effects of differences in milk homogeneity, especially with respect to casein micelles and fat globules.


Assuntos
Análise de Alimentos/métodos , Lactose/análise , Proteínas do Leite/análise , Leite/química , Espectrofotometria Infravermelho/métodos , Animais , Calibragem , Camelus , Caseínas/análise , Bovinos , Gorduras na Dieta/análise , Feminino , Reprodutibilidade dos Testes
6.
Food Chem ; 334: 127472, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32721831

RESUMO

Pyrrolizidine alkaloids (PAs) are naturally occurring plant toxins associated with severe liver damage if excessive ingestion. Herein, a novel analytical strategy on utilizing direct analysis in real-time mass spectrometry (DART-MS) was developed, and applied in analysis of six representative PAs. The calibration curves in the range of 10-1000 ng·mL-1 were established, and relative standard deviations (RSDs) were less than 10%. The limits of detection (LODs) and limits of quantitation (LOQs) were 0.55-0.85 ng·mL-1 and 1.83-2.82 ng·mL-1, respectively. The feasibility of method was indicated by analysing real samples including Gynura japonica, drug tablets, granules, and fresh cow's milk. Moreover, the results of DART-MS were in good agreement with those observed by high performance liquid chromatography mass spectrometry (HPLC-MS), but consumed less time without chromatographic separation. This research provides a facile fashion for safety assessment of herbal and food products containing PAs and presents promising applications in food, pharmaceutical and clinical analysis.


Assuntos
Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Preparações de Plantas/análise , Alcaloides de Pirrolizidina/análise , Animais , Asteraceae/química , Calibragem , Bovinos , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Limite de Detecção , Leite/química
7.
Gene ; 764: 145101, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-32877747

RESUMO

India is the world's largest milk producing country because of massive contribution made by cattle and buffaloes. In the present investigation, comprehensive comparative profiling of transcriptomic landscape of milk somatic cells of Sahiwal cattle and Murrah buffaloes was carried out. Genes with highest transcript abundance in both species were enriched for biological processes such as lactation, immune response, cellular oxidant detoxification and response to hormones. Analysis of differential expression identified 377 significantly up-regulated and 847 significantly down-regulated genes with fold change >1.5 in Murrah buffaloes as compared to Sahiwal cattle (padj <0.05). Marked enrichment of innate and adaptive immune response related GO terms and higher expression of genes for various host defense peptides such as lysozyme, defensin ß and granzymes were evident in buffaloes. Genes related to ECM-receptor interaction, complement and coagulation cascades, cytokine-cytokine receptor interaction and keratinization pathway showed more abundant expression in cattle. Network analysis of the up-regulated genes delineated highly connected genes representing immunity and haematopoietic cell lineage (CBL, CD28, CD247, PECAM1 and ITGA4). For the down-regulated dataset, genes with highest interactions were KRT18, FGFR1, GPR183, ITGB3 and DKK3. Our results lend support to more robust immune mechanisms in buffaloes, possibly explaining lower susceptibility to mammary infections as compared to cattle.


Assuntos
Búfalos/imunologia , Bovinos/imunologia , Imunidade/genética , Transcriptoma/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Búfalos/genética , Bovinos/genética , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Regulação para Baixo/imunologia , Feminino , Hematopoese/genética , Hematopoese/imunologia , Índia , Lactação/genética , Lactação/imunologia , Leite/citologia , Leite/imunologia , RNA-Seq , Transcriptoma/genética , Regulação para Cima/imunologia
8.
Food Chem ; 337: 127765, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799161

RESUMO

ß-Casomorphin-7 (BCM-7) is a heptapeptide dietary molecule derived from the digestion of the ß-casein of dairy and dairy products. In this review, we have covered the extensive details about BCM and its derived peptides out of the gastrointestinal and enzymatic digestion of milk and milk products, its structure and properties, and its immunological aspects related to human health among infants and adults of both genders. We have left judgment about BCM's pros and cons to the reader by describing the details in a cyclopedic perspective. In addition, a section on the possible ways to detect BCMs from their sources using proteomics, genome-based techniques, such as PCR and aptamers, and other analytical techniques equip the reader to get an idea about the details of the diagnostics available and possible applications in future. Overall, this review will provide information to the end-users of milk and milk products to enable them to make their own decisions about BCMs.


Assuntos
Endorfinas/química , Animais , Transtorno Autístico/patologia , Caseínas/química , Caseínas/metabolismo , Endorfinas/sangue , Endorfinas/farmacologia , Humanos , Imunidade Inata/efeitos dos fármacos , Leite/química , Leite/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
9.
Sci Total Environ ; 751: 141830, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33182002

RESUMO

This systematic review presents the potential toxicity of heavy metals such as lead (Pb), mercury (Hg), cadmium (Cd), iron (Fe), nickel (Ni), aluminum (Al), and copper (Cu) in raw cow milk, focusing on their contamination sources and on the assessment of the related human health risk. Multiple keywords such as "raw cow milk, heavy metals, and human health" were used to search in related databases. A total of 60 original articles published since 2010 reporting the levels of these metals in raw cow's milk across the world were reviewed. Data showed that the highest levels of Ni (833 mg/L), Pb (60 mg/L), Cu (36 mg/L) were noticed in raw cow milk collected in area consists of granites and granite gneisses in India, while the highest level of Cd (12 mg/L) was reported in barite mining area in India. Fe values in raw cow milk samples were above the WHO maximum limit (0.37 mg/L) with highest values (37.02 mg/L) recorded in India. The highest Al level was (22.50 mg/L) reported for raw cow's milk collected close to food producing plants region in Turkey. The Target Hazard Quotients (THQ) values of Hg were below 1 suggesting that milk consumers are not at a non-carcinogenic risk except in Faisalabad province (Pakistan) where THQ values = 7.7. For the other heavy metals, the THQ values were >1 for Pb (10 regions out of 70), for Cd (6 regions out of 59), for Ni (3 out of 29), and for Cu (3 out of 54). Exposure to heavy metals is positively associated with diseases developments. Moreover, data actualization and continuous monitoring are necessary and recommended to evaluate heavy metals effects in future studies.


Assuntos
Metais Pesados , Leite , Animais , Bovinos , Monitoramento Ambiental , Feminino , Humanos , Índia , Metais Pesados/análise , Metais Pesados/toxicidade , Leite/química , Paquistão , Medição de Risco , Turquia
10.
An Acad Bras Cienc ; 92(3): e20180925, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33053101

RESUMO

In this work, we investigated the phenotypic profile of Staphylococcus spp. isolates recovered from raw milk and artisanal cheese, and their enterotoxigenic potential through the detection of classical enterotoxin genes (sea, seb, sec, sed and see). A total of 104 isolates (58 coagulase-positive Staphylococcus - CoPS; and 46 coagulase-negative Staphylococcus- CoNS) were used, of which 33 were retrieved from raw milk and 71 from artisanal cheese produced in the Serrana region of Santa Catarina. Identification of CoPS was conducted via biochemical tests. Detection of the genes sea, seb, sec, sed, and see was carried out by multiplex PCR technique. Among the 58 CoPS analyzed, 64% were identified as S. aureus, 22% as S. scheiferi coagulans, 12% as S. hyicus and as 2% S. intermedius. In the present study was noted that 40% of CoPS isolates retrieved from milk harbored seb gene, while only one from artisanal cheese was positive for gene sea. In this study all CoNS samples investigated were negative for enterotoxins genes. The enterotoxigenic potential of CoPS, is an issue of great importance for public health. For that reason, it is necessary that cheese factories strictly follow the safety processes involved in manufacturing.


Assuntos
Queijo , Staphylococcus , Animais , Microbiologia de Alimentos , Leite , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Staphylococcus aureus
11.
Shokuhin Eiseigaku Zasshi ; 61(4): 148-153, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33012770

RESUMO

To determine the relationship between seasons and regions and aflatoxin M1 (AFM1) contamination of milk distributed in Fukuyama City, we conducted a survey once during the summer and once during the winter between June 2018 and January 2019. We compared the AFM1 contamination levels in milk drinks available in Fukuyama City during the same period, to provide more about the factors causing AFM1 contamination. All milk samples examined exhibited AFM1 contamination levels below the standard AFM1 contamination level (0.5 µg/kg). For the comparison based on seasons, one milk sample collected in the summer (0.07 µg/kg) exceeded the EU limit (heat-treated milk: 0.050 µg/kg). However, there was no significant difference in the AFM1 contamination level (p>0.05). For the comparison based on regions, the AFM1 contamination level in the milk sample from the Chugoku Region was significantly higher in the winter and significantly lower in the summer compared to those from other regions. AFM1 contamination of milk did not have a direct relationship with seasons or regions, but was instead influenced by the type, amount, and management of feed supplied to dairy cattle. For the comparison between milk and milk drinks, the AFM1 contamination levels in milk drinks were significantly lower (p<0.01). The highest AFM1 concentration (0.08 µg/kg) was detected in one sample of milk drink sampled during the summer. The AFM1 contamination of milk drinks is likely affected by the level of contamination in raw materials, the proportion of such raw materials in the drinks, and the process type. An increase in non-fat milk solids was assumed to be a factor that increases AFM1 contamination.


Assuntos
Aflatoxina M1 , Contaminação de Alimentos , Leite , Aflatoxina M1/análise , Animais , Contaminação de Alimentos/análise , Temperatura Alta , Leite/química , Estações do Ano
12.
Chemosphere ; 261: 128128, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113644

RESUMO

There is an increased production and demand for ewes' milk in the Republic of Croatia, as well as globally. There is also a growing concern about its quality, since milk from farm animals may become contaminated with mercury and other toxic elements. Thus, the aim of this paper is to determine the influence of lactation stage on the ewes' milk quality in western Croatia by considering concentrations of mercury and other elements in ewes' milk. The research was conducted on 36 Travnik pramenka sheep during different lactation stages. The digested milk samples were analysed with continuous flow hydride generation technique by using inductively coupled plasma mass spectrometry. Samples were taken during 40th, 80th and 120th d of lactation. Yield and quality of ewes' milk was within lactation curve. As lactation progressed, significantly lower concentrations of Hg (on 80th d compared to 40th d) and of Cd (120th d compared to 80th d) were noted, and Hg on 120th d was below the detection limit. Concentrations of Ca and Cu were lower on the 120th d compared to 40th d, while P, Mg, Fe, Zn, Mn, and Se were lower on the 80th and 120th d compared to the 40th d. Concentrations of K, Mo, and Cr differed among all stages of lactation. Regarding toxic elements, the observed low concentrations of Hg, Co, Cd and As suggest that ewes' milk in western Croatia is safe for human or animal consumption.


Assuntos
Contaminação de Alimentos/análise , Lactação , Mercúrio/análise , Leite/química , Ovinos , Animais , Croácia , Feminino , Humanos , Espectrometria de Massas , Espectrofotometria Atômica , Fatores de Tempo
13.
Int J Food Microbiol ; 335: 108888, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33027736

RESUMO

During the last decades, thermophilic spore counts became a very important quality parameter for manufacturers with regard to powdered dairy products. Low-spore count powders are highly demanded but challenging to produce when high production volume and long process times are intended. In this study a detailed monitoring of microbial levels in three skim milk powder plants was conducted. Anoxybacillus flavithermus was found to be primarily responsible for increased spore levels with increasing spore numbers being detected after 6-8 h already during initial processing steps. Simultaneously, the species composition shifted from a diverse bulk tank milk microbiota where different Bacillus species represented around 90% of the thermophilic bacteria to a dominance of A. flavithermus in the end product. The analysis of A. flavithermus isolates from different powder batches with RAPD PCR revealed recurring patterns in each of the eight German manufacturers sampled over several months. The high relatedness of isolates exhibiting identical RAPD patterns was exemplified by cgMLST based on whole genome sequences. We assume that A. flavithermus strains persisted in production plants and were not eliminated by cleaning. It is concluded that such persisting strains recurrently recontaminated subsequent powder productions. The data highlight that a targeted optimization of cleaning and disinfection procedures is the most promising measure to effectively reduce thermophilic spore counts in German dairy powders.


Assuntos
Laticínios/microbiologia , Bactérias Formadoras de Endosporo/isolamento & purificação , Manipulação de Alimentos , Esporos Bacterianos/isolamento & purificação , Animais , Contagem de Colônia Microbiana , Bactérias Formadoras de Endosporo/classificação , Bactérias Formadoras de Endosporo/genética , Microbiologia de Alimentos , Genoma Bacteriano/genética , Alemanha , Leite/microbiologia , Esporos Bacterianos/classificação , Esporos Bacterianos/genética
14.
Int J Food Microbiol ; 335: 108903, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33065381

RESUMO

Societal demand for plant-based foods is increasing. In this context, soya products fermented using lactic acid bacteria (LAB) are appealing because of their potential health and nutritional benefits. The thermophilic LAB Streptococcus thermophilus is an essential starter species in the dairy industry. However, while its physiology is well characterized, little is known about its general metabolic activity or its techno-functional properties when it is grown in soya milk. In this study, S. thermophilus LMD-9 growth, sugar production, and lactic acid production in soya milk versus cow's milk were measured. Additionally, the main metabolic pathways used by the bacterium when growing in soya milk were characterized using a proteomic approach. Streptococcus thermophilus LMD-9 growth decreased soya milk pH, from 7.5 to 4.9, in 5 h. During fermentation, acidification thus occurred in tandem with lactate production and increasing population size (final population: 1.0 × 109 CFU/ml). As growth proceeded, sucrose was consumed, and fructose was produced. The proteomic analysis (LC-MS/MS) of the strain's cytosolic and cell envelope-associated proteins revealed that proteins related to amino acid transport and nitrogen metabolism were the most common among the 328 proteins identified (63/328 = 19.2% of total proteins). The cell-wall protease PrtS was present, and an LMD-9 deletion mutant was constructed by interrupting the prtS gene (STER_RS04165 locus). Acidification levels, growth levels, and final population size were lower in the soya milk cultures when the ΔprtS strain versus the wild-type (wt) strain was used. The SDS-PAGE profile of the soluble proteins in the supernatant indicated that soya milk proteins were less hydrolyzed by the ΔprtS strain than by the wt strain. It was discovered that S. thermophilus can grow in soya milk by consuming sucrose, can hydrolyze soya proteins, and can produce acidification levels comparable to those in cow's milk. This study comprehensively examined the proteomics of S. thermophilus grown in soya milk and demonstrated that the cell-wall protease PrtS is involved in the LAB's growth in soya milk and in the proteolysis of soya proteins, which are two novel findings. These results clarify how S. thermophilus adapts to soya milk and can help inform efforts to develop new fermented plant-based foods with better-characterized biochemical and microbiological traits.


Assuntos
Proteínas de Bactérias/metabolismo , Serina Endopeptidases/metabolismo , Leite de Soja/metabolismo , Streptococcus thermophilus/crescimento & desenvolvimento , Streptococcus thermophilus/metabolismo , Animais , Fermentação , Ácido Láctico/análise , Ácido Láctico/metabolismo , Redes e Vias Metabólicas , Leite/química , Leite/metabolismo , Leite/microbiologia , Proteínas do Leite/metabolismo , Nitrogênio/metabolismo , Proteômica , Leite de Soja/química , Proteínas de Soja/metabolismo , Streptococcus thermophilus/enzimologia , Sacarose/metabolismo , Açúcares/análise , Açúcares/metabolismo
15.
Anim Sci J ; 91(1): e13441, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32885570

RESUMO

Microbiota of individual cow milk, bulk tank milk, and feces of Jersey cows were examined. Samples were collected from two farms (F1 and F2) in cool (November, Nov) and hot (July, Jul) seasons. Milk yield and milk composition were similar between the two farms and between the two seasons. Prevalent taxa of the fecal microbiota, i.e. Ruminococcaceae, Bacteroidaceae, Lachnospiraceae, Rikenellaceae, and Clostridiaceae, were unaffected by the farm and season. Relative abundance of milk microbiota for Pseudomonadaceae, Enterobacteriaceae, and Streptococcaceae (F1 > F2) and Lactobacillaceae, Bifidobacteriaceae, and Cellulomonadaceae (F1 < F2) were different between the two farms, and those for Staphylococcaceae, Bacillaceae, Ruminococcaceae, and Veillonellaceae (Nov < Jul) and Methylobacteriaceae and Moraxellaceae (Nov > Jul) were different between the two seasons. The microbiota of bulk tank milk was numerically different from that of individual cow milk. Principal coordinate analysis indicated that the milk microbiota was unrelated to the fecal microbiota. The finding that relative abundance of Pseudomonadaceae and Moraxellaceae appeared greater than those reported for Holstein milk suggested that higher protein and fat content may result in a greater abundance of proteolytic and lipolytic taxa in Jersey cow milk.


Assuntos
Bovinos/metabolismo , Bovinos/microbiologia , Temperatura Baixa , Indústria de Laticínios , Fazendas , Gorduras/metabolismo , Fezes/microbiologia , Temperatura Alta , Proteínas do Leite/metabolismo , Leite/metabolismo , Leite/microbiologia , Estações do Ano , Animais , Feminino , Moraxellaceae , Proteólise , Pseudomonadaceae
16.
Life Sci ; 260: 118415, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918974

RESUMO

AIMS: Previous studies have shown the effect of niacin on dairy cow production, but no study on the role of niacin in milk fat synthesis has been performed. Therefore, the purpose of this study was to examine the effect of niacin on milk fat synthesis and its specific mechanism in BMECs. MAIN METHODS: In this study, 0.5 mM niacin, a GPR109A-inhibiting plasmid, and an AMPK inhibitor were added to BMECs. Milk fat was measured by a triglyceride kit and BODIPY staining. The protein expression of GPR109A, FASN, SREBP1, AMPK, ACC, mTOR and S6K was measured by Western blotting. The gene expression of GPR109A, FASN, and SREBP1 was analysed by RT-PCR. KEY FINDINGS: Our results showed that 0.5 mM niacin could significantly reduce milk fat synthesis in BMECs and activate the AMPK/ACC signalling pathway by stimulating GPR109A, reducing the protein expression of p-mTOR and p-S6K, and reducing the expression of SREBP1 and FASN in BMECs. SIGNIFICANCE: The present study clarified the effect of niacin on milk fat synthesis. The results show that niacin inhibits the synthesis of milk fat in BMECs through the downstream signalling pathway mediated by GPR109A. The function of niacin has been expanded, and knowledge of the new mechanism and signalling pathway will help improve the biosynthesis of milk fat.


Assuntos
Gorduras na Dieta/metabolismo , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo , Leite/metabolismo , Niacina/farmacologia , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Bovinos , Células Epiteliais/efeitos dos fármacos , Feminino , Hipolipemiantes/farmacologia , Glândulas Mamárias Animais/efeitos dos fármacos , Leite/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/genética
17.
PLoS One ; 15(9): e0239260, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931511

RESUMO

Coxiella burnetii is a highly infectious zoonotic pathogen infecting wide range of mammals, including humans. In the present study, a total of 711 blood samples from bovines [cattle (n = 543) and buffaloes (n = 168)] from eight farms at different geographical locations in India were screened for C. burnetii targeting the IS1111 and the com1 genes. The anti-C. burnetii antibodies in serum samples were detected using indirect-ELISA kits. Also, a total of 21 parameters pertaining to animal health and farm management were identified to assess their role as possible risk factors for coxiellosis among the targeted farms. The apparent prevalence (positive for PCR and/or ELISA) for coxiellosis was reported to be 24.5% in cattle and 8.9% in buffaloes. In cattle, the detection rate of C. burnetii employing the IS1111 gene (8.5%) was found to be significantly higher (p<0.05) as compared to the com1 (6.5%) gene. The seropositivity by ELISA was higher among cattle (17.7%) than in buffaloes (8.3%). Further, on univariable analysis of risk factors, species (cattle) (OR:3.31; 95%CI:1.88-5.82), inadequate floor spacing (OR:1.64; 95%CI:1.10-2.43), mastitis (OR:2.35, 95%CI:1.45-3.81) and reproductive disorders (OR:2.54; 95%CI:1.67-3.85) were significantly (p<0.05) having high odds for coxiellosis. The multivariable logistic regression analysis of the animal level risk factors revealed that species and age were found to be significantly associated with coxiellosis. However, since the number of screened farms is limited; further research is needed with a higher number of animals to confirm the farm level odds ratio of risk factors. Quarantine and biosecurity measures including farm hygiene operations were observed to be inadequate and also the lack of awareness about coxiellosis among the farm workers. In absence of vaccination program for coxiellosis in India, robust surveillance, farm biosecurity measures and the awareness for the disease among risk groups can play an important role in the disease prevention and subsequent transmission of the pathogen.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/sangue , Coxiella burnetii/genética , Febre Q/sangue , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Coxiella burnetii/patogenicidade , Ensaio de Imunoadsorção Enzimática , Fazendeiros , Feminino , Humanos , Índia/epidemiologia , Leite/microbiologia , Reação em Cadeia da Polimerase , Febre Q/genética , Febre Q/microbiologia , Zoonoses/sangue , Zoonoses/genética , Zoonoses/microbiologia
18.
PLoS One ; 15(9): e0238921, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925944

RESUMO

The objective of this study was to characterize the chemical composition and lipid profile of colostrum and milk of purebred Quarter Horse mares. Thirty-four (34) purebred mares were selected, which were then separated into groups according to age, birth order and lactation stage. Colostrum samples were collected in the first six hours after delivery and milk samples from the 7th postpartum day, with intervals of 14 days until the end of lactation. The samples were refrigerated and sent to the Milk Laboratory of the University (Laboleite-UFRN), where they were analyzed for chemical composition. Colostrum was assessed by refractometry. The lipid profile was determined by gas chromatography through a separation of methyl esters. The data were tabulated and subjected to descriptive statistics and analysis of variance by the F-Test, and the groups were compared by the Tukey test using a significance level of 5%. There was high protein content and reduced lactose content for the colostrum of the Quarter Horse mares, differing from other breeds. The milk composition was not influenced by the mares' age. However, variations in the lactation stage and in the birth order of the Quarter Horse mares altered the milk's chemical composition. There is variation in the lipid composition of milk according to the lactation stage, without changing the characteristic profile of the mares' milk or diminishing the nutritional quality of the lipid fraction.


Assuntos
Colostro/química , Lipidômica/métodos , Lipídeos/análise , Leite/química , Animais , Peso Corporal , Cruzamento , Cromatografia Gasosa , Feminino , Cavalos , Valor Nutritivo , Gravidez , Refratometria
19.
Int J Food Microbiol ; 334: 108828, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32866940

RESUMO

Raw milk is a continued threat to public health due to possible contamination with zoonotic pathogens. Enterocytozoon bieneusi is one of the most prevalent pathogenic fungi in a wide range of vertebrate hosts, causing diarrheal disease. Although there has been some evidence, the role and potential risk of raw milk of dairy animals in the transmission dynamics of E. bieneusi is not clear. Therefore, we aimed to determine the occurrence and genotypes of E. bieneusi in raw milk of dairy animals in several farms of the Central Anatolia Region. We also investigated if there is a relation between the presence of E. bieneusi and mastitis. Genomic DNAs from a total of 450 raw milk including 200, 200 and 50 samples from cattle, sheep and water buffalo respectively were analyzed using nested PCR, targeting the internal transcribed spacer of E. bieneusi. Totally milk samples of 9 (4.5%) dairy cattle, 36 (18.0%) sheep, and 1 (2.0%) water buffalo were PCR-positive. A significant relationship was determined between mastitis and the presence of E. bieneusi. Sequence analysis revealed the presence of eight genotypes: two known (ERUSS1, BEB6) and six novel genotypes (named as TREb1 to TREb6). The genotype ERUSS1 and BEB6 were the most common genotypes, found in all cattle and sheep farms. Phylogenetic analysis clustered all the identified genotypes in Group 2. This study provides novel findings that contribute to the transmission dynamics and molecular epidemiology of E. bieneusi. Our study also highlighted the potential risk of raw milk for public health with respect to microsporidia infections.


Assuntos
Doenças dos Bovinos/epidemiologia , Enterocytozoon/genética , Microsporidiose/veterinária , Leite/microbiologia , Doenças dos Ovinos/epidemiologia , Animais , Búfalos , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/transmissão , Enterocytozoon/classificação , Enterocytozoon/isolamento & purificação , Fazendas , Feminino , Genótipo , Mastite/epidemiologia , Mastite/microbiologia , Mastite/veterinária , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Microsporidiose/transmissão , Epidemiologia Molecular , Filogenia , Prevalência , Ovinos , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/transmissão , Turquia
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