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1.
J Environ Manage ; 260: 110049, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090806

RESUMO

A compliant tool (CalcPEFDairy) to determine the Product Environmental Footprint (PEF) of Dairy products has been developed following the Product Environmental Footprint Category Rules (PEFCR) v.6.3 guidance and the 2018 approved PEFCR for Dairy products. CalcPEFDairy is a new tool that simplifies and reduces the work for LCA practitioners when implementing the PEFCR for Dairy products. On contrary to traditional LCA software, CalcPEFDairy includes all the emission models needed to calculate farm and crop cultivation direct emissions and it also implements the specific calculation formulas stated in the PEFCR such as the Circular Footprint and Data Quality Requirement formulas. Moreover, the PEF compliant datasets provided by the Life Cycle Data Network are incorporated in the tool as source of secondary data. To demonstrate the accuracy of the tool a traditional dairy farm in Catalonia (Northwest of Spain) was assessed and the results compared with the European representative PEF compliant datasets for the production of raw milk, cheese and yoghurt. In addition to the environmental profile, CalcPEFDairy has determined the case study's environmental single score (ESS) for the production of raw milk (1.0 × 10-4) cheese (9.7 × 10-6) and yoghurt (1.4 × 10-5); these ESS results are within the range of the ESS obtained from the analysed EF-datasets. The data sets' average ESS for raw milk is 9.9 × 10-5 ± 1.1 × 10-5, while for cheese and yoghurt are 1.5 × 10-5 ± 3.1 × 10-6 and 1.9 × 10-5 ± 3.4 × 10-6 respectively. A 78% of the raw milk production ESS is attributed to the dairy farm activities while, the raw milk production stage affects in a 87.4% and 80.1% to the ESS for cheese and yoghurt respectively.


Assuntos
Queijo , Indústria de Laticínios , Animais , Pegada de Carbono , Laticínios , Leite , Espanha
2.
J Agric Food Chem ; 68(9): 2826-2831, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32045247

RESUMO

In this work, we have developed an all-in-one aptasensor based on an enzyme-driven three-dimensional DNA walker for antibiotic detection. To overcome the drawback of time-consuming methods, high-density substrate strands were anchored on the walking interface that accelerated the signal amplification efficiency. Such an all-in-one design integrated the functionality of target recognition, signal amplification, as well as signal output into a single probe. Upon addition of kanamycin, the activated walking strand moved along the track by the stepwise cleavage of a nicking enzyme, which resulted in the enhancement of the fluorescence intensity of the solution. Under the optimized conditions, the detection process was accomplished in 40 min with a low detection limit of 1.23 pM. This aptasensor was also applied in spiked milk samples with satisfactory recoveries of 97.76% to 105.33%, demonstrating an excellent stability and accuracy. Therefore, this all-in-one aptasensor shows great potential for applications in food safety.


Assuntos
Antibacterianos/análise , Técnicas Biossensoriais/métodos , Animais , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/instrumentação , Bovinos , Contaminação de Alimentos/análise , Ouro/química , Canamicina/análise , Limite de Detecção , Leite/química
3.
J Agric Food Chem ; 68(10): 3277-3285, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054265

RESUMO

5-Hydroxy-l-tryptophan (5-HTP) is the primary product that converts l-tryptophan into 5-hydroxytryptamine by a rate-limiting enzyme. Our previous study found that 5-HTP could promote the intracellular calcium level in goat mammary epithelial cells (GMECs). Herein, first, dairy goats were injected with 5-HTP or saline daily from 7 days before delivery, and the calcium level in colostrum of 5-HTP-injected goats was significantly higher than that of saline-injected goats. Moreover, miR-99a-3p expression was significantly increased after 5-HTP treatment from transcriptome sequencing analysis and quantitative real-time polymerase chain reaction. In addition, it was found that ATP2B1 is one of the target genes of miR-99a-3p predicted by bioinformatic methods, which plays a crucial role in the maintenance of intracellular calcium homeostasis of mammary epithelial cells. Next, we confirmed that miR-99a-3p could increase the intracellular calcium level via decreasing ATP2B1 in GMECs. Taken together, we draw the conclusion that 5-HTP promotes the calcium level in colostrum possibly by increasing intracellular calcium of mammary epithelial cells induced by the miR-99a-3p/ATP2B1 axis.


Assuntos
5-Hidroxitriptofano/administração & dosagem , Cálcio/metabolismo , Células Epiteliais/metabolismo , Cabras/metabolismo , Glândulas Mamárias Animais/metabolismo , MicroRNAs/genética , Leite/química , Animais , Cálcio/análise , Células Epiteliais/efeitos dos fármacos , Feminino , Cabras/genética , Lactação , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/efeitos dos fármacos , MicroRNAs/metabolismo , Leite/metabolismo
4.
J Agric Food Chem ; 68(7): 2201-2213, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32023042

RESUMO

A feeding study was carried out to investigate the kinetics in cow milk of the 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), the 12 dioxin-like polychlorinated biphenyls (DL-PCBs), and the 6 non-dioxin-like PCBs (NDL-PCBs) regulated by the European (EU) legislation. A fortified ration (ΣPCDD/Fs and DL-PCBs: 24.68 ng TEQ/day/cow; ΣNDL-PCBs: 163.99 µg/day/cow) was given to the animals for 49 days, followed by 42 days on clean feed. EU maximum limit for TEQPCDD/F+DL-PCB was exceeded in milk after 1 week of exposure, while for ΣNDL-PCBs, after 5 weeks. Milk compliance was restored after 1 week on clean feed, but to return to the basal TEQPCDD/F+DL-PCB it took 42 days. At the end of the study, ΣNDL-PCBs had not yet reached the basal level. The carryover rate of ΣNDL-PCBs was 25.4%, while the carryover rate of TEQPCDD/F+DL-PCB was 36.9%. The latter was mainly affected by the 12 congeners contributing most to the toxic equivalent (TEQ) level, explaining the fast overcome of the maximum limit in milk.


Assuntos
Dibenzofuranos/análise , Contaminação de Alimentos/análise , Leite/química , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Ração Animal/análise , Animais , Bovinos , Dioxinas/análise , Feminino
6.
Sci Total Environ ; 714: 136823, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31991276

RESUMO

The widespread dispersal of microplastic (plastic particle <5 mm) contamination in human food chain is gaining more attention in the public arena and scientific community. Better assessment of diversified consumer products is a key for combating problems related to microplastic contamination. To the best of our knowledge, no study has been conducted on dairy milk products, and the current research status of microplastics is lacking. Here, a total of 23 milk samples (22 adult and 1 kid) from 5 international and 3 national brands of Mexico was collected and tested for the occurrence of microplastics. Results confirmed the ubiquity of microplastics in the analyzed samples and showed variability ranging between 3 ± 2-11 ± 3.54 particles L-1 with an overall average of 6.5 ± 2.3 particles L-1 which are lower than any reported levels in liquid food products. Microplastic particles exhibited variety of colors (blue, brown, red and pink), shapes (fibers and fragments) and sizes (0.1-5 mm). Among which, blue colored fibers (<0.5 mm) were predominant. Micro-Raman identification results revealed that thermoplastic sulfone polymers (polyethersulfone and polysulfone) were common types of microplastics in milk samples, which are highly used membrane materials in dairy processes. Thus, this study findings developed a baseline outlook for microplastics contamination in dairy products and posed a great deal to take necessary controls and preventive measures to avoid them.


Assuntos
Plásticos , Adulto , Animais , Monitoramento Ambiental , Humanos , México , Leite , Poluentes Químicos da Água
7.
J Agric Food Chem ; 68(4): 1118-1125, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31895982

RESUMO

The conventional colloidal gold immunochromatographic assay (AuNP-ICA) cannot meet the requirements for the rapid and sensitive detection of Escherichia coli (E. coli) O157:H7 because of its poor sensitivity. Herein, a novel two-step cascade signal amplification strategy that integrates in situ gold growth and nanozyme-mediated catalytic deposition was proposed to enhance the detection sensitivity of conventional AuNP-ICA dramatically. The enhanced strip displayed ultrahigh sensitivity in E. coli O157:H7 detection and had a detection limit of 1.25 × 101 CFU/mL, which is approximately 400-fold lower than that of traditional AuNP-ICA (5 × 103 CFU/mL). The amplified strip had no background signal in the T-line zone in the absence of E. coli O157:H7 even after one round of cascade signal amplification. The enhanced strip demonstrated excellent selectivity against E. coli O157:H7 with a negligible cross-reaction to nine other common pathogens. Intra-assays and interassays showed that the improved strip has acceptable accuracy and precision for determining E. coli O157:H7. The average recoveries in a real milk sample ranged from 87.33 to 112.15%, and the coefficients of variation were less than 10%. The enhanced strip also showed great potential in detecting a single E. coli O157:H7 cell in a 75 µL solution.


Assuntos
Escherichia coli O157/isolamento & purificação , Imunoensaio/métodos , Leite/microbiologia , Animais , Bovinos , Escherichia coli O157/genética , Limite de Detecção
8.
Vet Q ; 40(1): 43-50, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31939335

RESUMO

Background: The coinfection process of Escherichia coli, an etiological agent of clinical mastitis and Mycobacterium avium subsp. paratuberculosis (MAP), a non-mastitic etiological agent in the bovine mammary gland is not fully known.Objective: Verify the ability of MAP to interfere with the invasion and translocation of E. coli in bovine mammary epithelial cell line (MAC-T).Methods: For the invasion assay, MAC-T cells were challenged with MAP K10 for 2 h and then challenged with E. coli for 10, 30 and 120 min. For the translocation assay, the trans well plates were used and the challenge sequence was repeated as previously described. The amount of E. coli in the assays was determined by counting colony forming units (CFU) in Luria-Bertani medium. Quantitative real-time PCR was used to quantify MAP in MAC-T cells. To verify the viability of the MAC-T cells, the MTT assay was performed. MAP culture supernatant was also evaluated at different percentages for E. coli growth.Results: Previous MAP infection in MAC-T cells inhibited E. coli invasion in 10, 30 and 120 min. No significant interference of MAP in the translocation of E. coli from the apical-basal direction was verified. Quantity of MAP DNA inside the MAC-T cells was statistically similar. Neither reduction in MAC-T cells viability was detected during the experiment nor MAP-released factor in the supernatant inhibited E. coli invasion.Conclusion: These findings suggest that MAP-positive cows could be more resistant to E. coli infection, but when infected, could rapidly translocate E. coli to the subepithelial region.


Assuntos
Translocação Bacteriana/fisiologia , Coinfecção/veterinária , Células Epiteliais/microbiologia , Escherichia coli/patogenicidade , Mastite Bovina/microbiologia , Mycobacterium avium subsp. paratuberculosis/patogenicidade , Animais , Bovinos , Linhagem Celular , Coinfecção/microbiologia , Modelos Animais de Doenças , Infecções por Escherichia coli/veterinária , Feminino , Glândulas Mamárias Animais/microbiologia , Leite/microbiologia , Paratuberculose
9.
Environ Monit Assess ; 192(2): 112, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31938971

RESUMO

This study aimed to measure zinc (Zn), selenium (Se), copper (Cu), iron (Fe), chromium (Cr), nickel (Ni), lead (Pb), cadmium (Cd), arsenic (As), and aluminum (Al) in whole, semi-skimmed, skimmed, organic, fruit-flavored (strawberry, banana, and cocoa), pasteurized, and raw cows' milk. The samples were collected from sterilized and pasteurized milk processed in different ways in Ankara; the milk was kept in refrigerated raw milk storage tanks on dairy farms. Ninety samples were collected, and there were ten samples in each group. Analyses were performed using inductively coupled plasma-mass spectrometry. Lead and Cd were not found in any samples, while Zn was observed in all samples. The element with the highest frequency of occurrence was Zn, followed by Cr = As> Al > Se > Fe > Ni > Cu > Pb = Cd, in decreasing order. The lowest concentration among the essential elements was seen in Cu. Aluminum and As were found in 85% and 94.45% of the samples, respectively. However, the present concentrations were below the level of a probable negative effect. It was found that the concentrations of elements in milk showed statistically significant differences, depending on the milk type. It is recommended that low-quality materials not be used in the preparation of milk; the element concentrations in milk and the feed and water consumed by animals should be controlled regularly, and the animals should not be pastured near industrial and traffic sites to protect public health.


Assuntos
Leite , Oligoelementos , Animais , Bovinos , Cromo , Cobre , Monitoramento Ambiental , Feminino , Leite/química , Oligoelementos/análise , Zinco
10.
J Endod ; 46(3): 370-375, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31959484

RESUMO

INTRODUCTION: Tooth replantation is the treatment of choice for avulsion, even though its long-term prognosis shows great variability and few studies have adopted survival analysis to evaluate the fate of such teeth. The present study aimed to evaluate both the survival rate of replanted permanent teeth after traumatic avulsion as well as its clinical and demographic determinants. METHODS: Records from 576 patients treated at the Dental Trauma Clinic at the Federal University of Minas Gerais, Brazil, were analyzed to collect clinical and radiographic data. Kaplan-Meier curves and a multivariate Cox regression model were used to estimate the probability of replanted teeth remaining functional in the mouth and to determine prognostic factors. RESULTS: The post-replantation survival rate was 50% after 5.5 years. Immature teeth presented an increase of 51.3% in the loss rate (P = .002). Each additional year in the patient's age at the time of trauma, up to the limit of 16 years, reduced the loss rate of replanted teeth by 15% (P < .001). The storage of the avulsed teeth in milk decreased the loss rate of replanted teeth by 56.4% (P = .015) when compared with those kept dry. CONCLUSIONS: The overall survival rate after replantation of permanent teeeth was 50% after 5.5 years. Advanced stages of root development, together with the increase in the patient's age at the moment of trauma, up to the limit of 16 years, were good prognostic factors for tooth survival. The storage of avulsed teeth in milk was also associated with enhanced tooth survival after replantation.


Assuntos
Reabsorção da Raiz , Avulsão Dentária , Reimplante Dentário , Animais , Brasil , Dentição Permanente , Humanos , Leite
11.
Food Microbiol ; 87: 103376, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948617

RESUMO

Dry dairy powder is a commonly used ingredient for ready-to-eat foods. It has been implicated in multiple foodborne outbreaks. Listeria monocytogenes can survive in low-moisture conditions for a long duration. However, there is no information on Listeria survival in dry milk powder during storage and thermal treatments. The objectives of this study were to examine the stability of L. monocytogenes in non-fat dry milk (NFDM) during extended storage and further analyze thermal resistance of L. monocytogenes in NFDM under different water activities (aw) and its thermal stability after 1-year storage. We observed approximately 1.75 and 2.93 log CFU/g reduction of L. monocytogenes in aw 0.25 NFDM over 1-year storage at 4 and 22 °C, respectively. Thermal resistance of L. monocytogenes was inversely related to aw, and the inactivation kinetic curves of L. monocytogenes in NFDM at target aw showed a log-linear trend under all tested conditions. For aw 0.25, 0.30, and 0.45 NFDM, the ranges of D-values, were 66.2-21.3, 33.5-9.4, and 14.6-4.3 min at 70, 75 and 80 °C, respectively. The z-values for L. monocytogenes in NFDM at aw 0.25-0.45 were 14.6-16.0 C°. Furthermore, the thermal stability of L. monocytogenes in aw 0.25 NFDM post 6-month or 12-month storage under refrigerated or ambient temperature did not deviate much from that in NFDM prior to the storage. Data indicated that a 60-min heat treatment at 80 °C resulted in ~ 5-log reduction of L. monocytogenes in NFDM of aw 0.30. This provides a promising intervention strategy to enhance bactericidal efficacy of thermal treatment while maintaining the quality of milk powder.


Assuntos
Listeria monocytogenes/crescimento & desenvolvimento , Leite/microbiologia , Animais , Bovinos , Contagem de Colônia Microbiana , Armazenamento de Alimentos , Temperatura Alta , Listeria monocytogenes/metabolismo , Leite/química , Pós/química , Temperatura Ambiente , Água/análise , Água/metabolismo
12.
Food Microbiol ; 87: 103383, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31948624

RESUMO

Thermophilic and mesophilic lactic acid bacteria (LAB), such as Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus helveticus, and Lactococcus lactis, play a crucial role in the technological and sensory quality of Mozzarella cheese. In this study, the safety (genes encoding virulence factors and antibiotic resistance) and acidifying activity of autochthonous S. thermophilus cultures were evaluated in order to choose the most suitable strain for industrial application. The safe and good acidifying culture was tested in two buffalo Mozzarella cheese batches: Mozzarella cheeses produced with autochthonous culture (SJRP107) and commercial culture (STM5). The cultivable LAB was evaluated by culture-dependent method (plate counting) and the quantification of S. thermophilus cultures (commercial and autochthonous) were evaluated by culture-independent method RealT-qPCR (real-time quantitative polymerase chain reaction). The texture, physicochemical and proteolytic properties of the Mozzarella cheeses were similar for both batches. The nonstarter LAB count was higher during manufacture than in the storage, and the RealT-qPCR indicated the presence of S. thermophilus culture until the end of storage. S. thermophilus SJRP107 presented high potential for safety application in the production of Mozzarella cheese. Furthermore, considering the culture characteristics and their relationship with product quality, further studies could be helpful to determine their effect on the sensory characteristics of the cheese.


Assuntos
Queijo/microbiologia , Leite/microbiologia , Streptococcus thermophilus/crescimento & desenvolvimento , Streptococcus thermophilus/metabolismo , Animais , Búfalos , Queijo/análise , Qualidade de Produtos para o Consumidor , Fermentação , Microbiologia de Alimentos , Humanos , Streptococcus thermophilus/genética , Streptococcus thermophilus/isolamento & purificação , Paladar
13.
Vet Parasitol ; 277: 109016, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31901738

RESUMO

Infections with the liver fluke Fasciola hepatica remain a serious problem in dairy herds causing significant production losses. In sheep, a strong relationship between F. hepatica infections and an increase in serum ketone bodies due to reduced feed intake and liver damage was demonstrated. We hypothesized that F. hepatica infections might contribute to an increase in milk ketone bodies in dairy herds. Thus, the objective of the study was to estimate the association between F. hepatica bulk tank milk (BTM) antibodies and milk production parameters (milk yield, milk protein, fat yield), somatic cell count (SCC) and the milk ketone bodies ß-hydroxybutyrate (BHB) and acetone, inferred from Fourier transform infrared (FTIR) spectrometry, via linear mixed model analysis. A further aim was to follow up the F. hepatica seroprevalence in dairy herds in the northern German region East Frisia. We collected BTM samples between October and December from 1022 herds in 2017 and 1318 herds in 2018. Overall, 33.1 % of the herds tested positive in 2017 and 37.0 % in 2018, showing decreased F. hepatica seroprevalences compared to prior seroprevalence studies in the same region in 2010, 2008 and 2006 (> 45 % positive herds). We estimated a significant negative association (P < 0.001) between herd F. hepatica infection category and average milk yield with a loss of -1.62 kg per cow per day in strongly infected herds compared to BTM ELISA negative herds. Moreover, F. hepatica infection category had a significant effect on herd average milk protein and fat yield (P < 0.001), showing a decrease of 0.06 kg for both parameters from BTM ELISA negative herds to strongly infected herds. No significant association with milk SCC was found (P = 0.664). Regarding ketone bodies, we estimated significant higher average BHB values in strongly infected herds compared to the other three infection categories in the model analysis (P = 0.002). The association between F. hepatica infection category and acetone values was not significant (P = 0.079). Besides primary ketosis, fasciolosis should be considered as differential diagnosis in dairy herds with increased BHB values.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/patologia , Fasciolíase/veterinária , Cetonas/análise , Lactação/fisiologia , Leite/química , Animais , Anticorpos Anti-Helmínticos/sangue , Bovinos , Indústria de Laticínios , Fasciola hepatica , Fasciolíase/epidemiologia , Fasciolíase/patologia , Alemanha , Estudos Soroepidemiológicos
14.
Monogr Oral Sci ; 28: 77-90, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31940625

RESUMO

Milk is an important part of the human diet; after weaning, cow's milk (bovine milk) predominates and this chapter considers the effect of bovine milk on dental caries. Yoghurt, which is a milk product, is also considered here. Several published reviews have concluded that milk is of very low cariogenicity and may have some caries protective potential. For example, WHO reviewed the strength of the evidence in 2003 and concluded that a "decreased risk" of dental caries from milk was "possible." The evidence comes from several types of study: epidemiological studies (interventional and observational), animal experiments, plaque pH studies, and in vivo and in vitro enamel and dentine slab experiments. More recent observational epidemiological studies have adjusted for potential confounders and have reported that milk consumption is associated with lower caries experience or incidence. Other types of study generally support this conclusion. Reasons for these favourable caries-related properties include the lower acidogenicity of lactose compared with other dietary sugars and the protective effects of calcium, phosphate, proteins, and fats. There is less research concerning yoghurts but it is likely that the cariogenic potential of plain yoghurt is similar to that of milk. The addition of sucrose to milk increases caries risk.


Assuntos
Cárie Dentária , Animais , Bovinos , Esmalte Dentário , Feminino , Humanos , Leite , Streptococcus mutans , Iogurte
15.
Water Res ; 171: 115466, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31927094

RESUMO

Intense pressure on water resources has led to efforts to reuse reclaimed processing wastewater for cleaning purposes in food processing plants. The milk industry produces considerable amounts of wastewater, which can be used for cleaning of equipment after appropriate treatment. However, due to naturally occurring microbiological contamination in raw milk, the wastewater is often contaminated, and therefore the reuse of reclaimed wastewater is perceived as risky. This study aims to quantify the risks of Listeria monocytogenes infection and associated disease burden when wastewater reclaimed from milk processing operations is used in cleaning-in-place (CIP) systems for pasteurized fluid milk production following a quantitative microbial risk assessment (QMRA) approach. Furthermore, this study aims to inform risk-based tolerable limits for levels of contamination in CIP water based on a public health target of 10-6 DALY per person annually. The suggested model investigates the passage of L. monocytogenes throughout the fluid milk chain, from receipt of raw milk at the plant to the point of consumption and covering storage in receiving and storage tanks, pasteurization, and storage at retail and at home. Risk and disease burden estimates are simulated for general (younger than 65 years), elderly (65 years and older) and pregnant population subgroups. Additional scenarios covering the effect of using clean water, using water with different levels of contamination and using reclaimed wastewater modeled as recovered from cheese whey after membrane filtration (reclaimed water scenario) are considered to estimate a risk-based limit of contamination and simulate a real-life example. The tolerable limit of contamination in CIP water was estimated as -2 log10 CFU/mL to ensure the protection of the most vulnerable subgroup, pregnant women, while higher limits were estimated for the elderly and general subgroups. Under the reclaimed water scenario, the annual number of listeriosis cases was estimated as 3.36, 5.67, and 0.15 for the general, elderly and pregnant population subgroups, respectively, while in the clean water scenario, the estimates were 3.33, 5.56 and 0.15, respectively. In both scenarios, the DALY estimates were lower than the tolerable limit. The results indicate that reclaimed water can be an alternative to potable water for CIP applications.


Assuntos
Listeria monocytogenes , Animais , Feminino , Contaminação de Alimentos , Manipulação de Alimentos , Humanos , Leite , Gravidez , Medição de Risco , Águas Residuárias
16.
DNA Cell Biol ; 39(3): 389-397, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31905020

RESUMO

Acetate and ß-hydroxybutyrate (BHBA) are the predominant substrates for de novo fatty acid (FA) synthesis in mammary gland of dairy cow. To investigate the nutrigenomic role of acetate and BHBA in bovine mammary epithelial cells during milk fat production, RNA sequencing (RNA-seq) transcriptomic analysis was used to identify differentially expressed genes (DEGs) between acetate- and BHBA-treated cells (high-milk fat cells) and control cells. A total of 625 DEGs (358 upregulated and 267 downregulated) were identified between the high-milk fat cells and control cells. Gene ontology enrichment analysis revealed that the upregulated genes in high-milk fat cells were mainly involved in lipid biosynthetic process, steroid biosynthetic process, oxidation-reduction process, receptor binding, and vesicle and small molecule biosynthetic process. The downregulated genes were mainly associated with immune response, cytokine production, negative regulation of biological process, and peptidyl-threonine modification. Pathway analysis indicated that FA metabolism and steroid biosynthesis were significantly enriched for the upregulated genes in the high-milk fat cells, while apoptosis was enriched for the downregulated genes. This work provides a profile of gene expression changes that occur during acetate- and BHBA-induced milk fat synthesis in bovine mammary epithelial cells, which furthers our understanding of the molecular regulation of lipid metabolism.


Assuntos
Ácido 3-Hidroxibutírico/metabolismo , Acetatos/metabolismo , Bovinos/genética , Células Epiteliais/metabolismo , Glândulas Mamárias Animais/metabolismo , Leite/metabolismo , Transcriptoma , Animais , Células Cultivadas , Ácidos Graxos/metabolismo , Feminino , Perfilação da Expressão Gênica , Glândulas Mamárias Animais/citologia , Nutrigenômica
17.
Food Chem ; 313: 125930, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31923863

RESUMO

A method based on gas chromatography coupled with triple quadrupole mass spectrometry (GC-MS/MS) combined with QuEChERS extraction was developed to detect furfurals, including furfural, 2-acetylfuran, 5-methyl-2-furfural, and 5-hydroxymethyl-2-furfural, in milk-based dairy products. Under the optimized conditions, good linearity was obtained with correlation coefficients (R2) above 0.999, and the recovery values from the spiked samples were 79.0%-115.0% with relative standard deviations (RSDs) less than 13.1%. The limits of detection (LODS) were in the range of 0.002-0.02 mg/kg. To investigate the effects of the production process on milk-based dairy products, 55 real samples were analysed. The higher contents of furfurals were observed when higher temperatures were used during heat treatment and fermentation. In addition, the Toxtree and T.E.S.T. software programs were used to predict the risks associated with these four furfurals. Ultimately, safe dairy intake levels were determined.


Assuntos
Laticínios/análise , Furaldeído/análise , Leite/química , Animais , Furaldeído/análogos & derivados , Furanos/análise , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Temperatura Ambiente
18.
Food Chem ; 313: 125822, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31931419

RESUMO

Concentrated pomegranate peel extract (CPE) was supplemented to ewes, and milk yield and fat content-fatty acid (FA) and phospholipid (PL) composition-were monitored. CPE-fed ewes had higher milk yield, and fat, protein and lactose contents than controls. Milk PL content-20% higher in the CPE-supplemented group-was regulated by treatment and not by total fat content; milk phosphatidylethanolamine and phosphatidylcholine increased by 22 and 26%, respectively, in CPE-supplemented vs. control ewes. Milk saturated FA concentration was higher, and total polyunsaturated and monounsaturated FA content lower in the CPE vs. control group, regardless of milk total fat content. CPE supplementation increased milk antioxidant capacity, suggesting antioxidant transfer from dietary source to milk, increasing stability and nutritive value. Our study provides first evidence for milk quality improvement in terms of antioxidants and PL enrichment without compromising total milk fat, suggesting strategies to improve dairy animals' milk composition without compromising total production.


Assuntos
Antioxidantes/metabolismo , Dieta , Leite/química , /química , Ração Animal/análise , Animais , Antioxidantes/química , Dieta/veterinária , Ácidos Graxos Monoinsaturados/análise , Feminino , Lactação , Leite/metabolismo , Valor Nutritivo , Fosfatidilcolinas/análise , Fosfatidiletanolaminas/análise , Ovinos
19.
J Agric Food Chem ; 68(6): 1725-1730, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31967806

RESUMO

Milk powders in the United States (US) may contain nitrates and nitrites from several potential sources. These sources include the ingestion of nitrates and nitrites by dairy cows during grazing and drinking, nitric acid used during the sanitization of dairy equipment, and the production of nitrous oxides in directly heated spray dryers. Recently, milk powders manufactured in the US have been rejected during import to other countries because nitrite concentrations were greater than 2 mg/kg (ppm). To date, the concentrations of nitrates and nitrites in milk and plant-based powders in the US are unknown. In this study the nitrate and nitrite concentrations present in diverse milk powders were investigated including 81 milk powders from local and online retailers from 2015 to 2018. In addition, 71 commercial milk powders were obtained from blinded production facilities. Nitrate and nitrite concentrations were determined using ion chromatography with conductivity and UV detection. A subset of samples was analyzed for N-nitrosodimethylamine using gas chromatography-mass spectrometry. Carbon and nitrogen bulk isotope ratios analyzed using isotope ratio mass spectrometry were used to obtain some insights into the production method (organic vs conventional) and geographic source of the milk powder samples. Background nitrate concentrations in US-produced milk powder samples averaged 17 ± 12 mg/kg. Nitrite was detected at concentrations greater than 2 mg/kg in 5 out of 39 different brands of retail milk and plant-based powders. Of these brands, two were plant-based (soy and coconut) powders and the other three had consistently high nitrites. The analysis of milk powders using stable isotope analysis revealed further information about the cow's diet.


Assuntos
Leite/química , Nitratos/análise , Nitritos/análise , Plantas/química , Ração Animal/análise , Animais , Bovinos/metabolismo , Leite/economia , Leite/metabolismo , Nitratos/metabolismo , Nitritos/metabolismo , Plantas/metabolismo , Pós/química , Pós/economia
20.
J Sci Food Agric ; 100(3): 1118-1123, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31667844

RESUMO

BACKGROUND: Dairy farming feed can be contaminated with mycotoxins, affecting animals' health and milk quality. Dairy farming is also prone to occupational exposure to mycotoxins, and feed is recognized as a source of contamination in the workplace. An exploratory study was developed in a dairy farm located in Portugal intending to assess the mycotoxins present in the feed. RESULTS: All the samples analyzed presented contamination by at least two mycotoxins and up to a maximum of 13 mycotoxins in the same sample. Zearalenone (ZEA) was detected in all the samples (n = 10) followed by deoxynivalenol (DON), which was reported in eight samples, and ochratoxin A (OTA), reported in five samples. CONCLUSION: The results point to the possible contamination of milk by several mycotoxins and raise the possibility of occupational exposure to mycotoxins due to feed contamination. An adequate One Health approach for dairy production should address these issues through effective preventive actions such as avoiding the use of feed contaminated with mycotoxins. This represents an important challenge due to climate change. It requires proper attention and accurate management measures. © 2019 Society of Chemical Industry.


Assuntos
Doenças dos Trabalhadores Agrícolas/etiologia , Ração Animal/análise , Leite/química , Micotoxinas/análise , Exposição Ocupacional/efeitos adversos , Doenças dos Trabalhadores Agrícolas/prevenção & controle , Animais , Bovinos , Fazendeiros/estatística & dados numéricos , Fazendas , Contaminação de Alimentos/análise , Humanos , Micotoxinas/toxicidade , Exposição Ocupacional/análise , Exposição Ocupacional/prevenção & controle , Ocratoxinas/análise , Ocratoxinas/toxicidade , Portugal , Zearalenona/análise , Zearalenona/toxicidade
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