RESUMO
Road scene understanding is crucial to the safe driving of autonomous vehicles. Comprehensive road scene understanding requires a visual perception system to deal with a large number of tasks at the same time, which needs a perception model with a small size, fast speed, and high accuracy. As multi-task learning has evident advantages in performance and computational resources, in this paper, a multi-task model YOLO-Object, Drivable Area, and Lane Line Detection (YOLO-ODL) based on hard parameter sharing is proposed to realize joint and efficient detection of traffic objects, drivable areas, and lane lines. In order to balance tasks of YOLO-ODL, a weight balancing strategy is introduced so that the weight parameters of the model can be automatically adjusted during training, and a Mosaic migration optimization scheme is adopted to improve the evaluation indicators of the model. Our YOLO-ODL model performs well on the challenging BDD100K dataset, achieving the state of the art in terms of accuracy and computational efficiency.
Assuntos
Veículos Autônomos , Aprendizagem , Registros , SoftwareRESUMO
BACKGROUND: A significant correlation has been discovered between social participation and older adults' life satisfaction, but the relationships among social participation, psychological resilience, and life satisfaction remain to be confirmed. Therefore, this study aims to identify the relationship between social participation and life satisfaction for Chinese older adults and to analyse the possible mediating role of psychological resilience between these two aspects. METHODS: Data on 15,779 people aged 65 years and above were extracted from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Social participation was classified into two levels: low-level involvement activities and high-level involvement activities. Hierarchical regression analysis was applied to analyse the correlations between the two levels of social participation and older adults' life satisfaction as well as the mediating effects of psychological resilience on this association. RESULTS: The results indicate that two levels of social participation were each positively correlated with life satisfaction. Specifically, high-level involvement activities (ß = 0.070, P < 0.001) were more strongly associated with life satisfaction than low-level involvement activities (ß = 0.051, P < 0.001). Moreover, psychological resilience was found to partially mediate the association between low-level involvement activities and high-level involvement activities and life satisfaction. CONCLUSION: A higher level of life satisfaction for older adults is related to participation in high-level involvement activities. Psychological resilience has a mediating effect on the association between two levels of older adults' social participation and life satisfaction. These findings suggest that the government and society should establish a more concrete understanding of the psychological resilience of older adults.
Assuntos
Resiliência Psicológica , Participação Social , Humanos , Idoso , China/epidemiologiaRESUMO
In this paper, the components of Zanthoxylum bungeanum Maxim. essential oil (ZBMEO) were analyzed. The efficacy of different concentrations of ZBMEO on the change in physical and chemical indicators of the rabbit meat patty was evaluated. Furthermore, kinetics models were employed to calculate the lipid oxidation induction period and microbial growth lag time. GC-MS analysis revealed that the major chemical components in ZBMEO included linalool, limonene, and sabinene. Results of the storage experiment indicated that ZBMEO had a good inhibition effect on lipid and protein oxidation, microbial growth, and formation of TVB-N, as well as slowed down the rate of change in color and pH during the 12 days storage time of rabbit meat. The models showed that adding ZBMEO could delay the lipid oxidation induction period, and extend the microbial growth lag time. Overall data showed that ZBMEO is a promising natural additive to maintain the quality of rabbit meat patty.
RESUMO
While Shiga toxin-producing Escherichia coli (STEC) is a major foodborne pathogen worldwide, data on the molecular and phylogenetic properties of STEC isolates from retail beef samples in China remain scant. Fresh retail beef samples (n = 1062) were collected from eight provinces, and STEC isolates were recovered and characterized. PCR data showed that more than 50% of the samples were stx positive, and 82 STEC isolates were recovered from 14.8% (79/535) stx-positive enriched broths. In contrast, all ciprofloxacin resistant isolates (n = 19) and 13 cefotaxime (CTX) resistant isolates were eae positive and belonged to three serotypes: O111:H8, O26:H11, or O157:H7. Point mutations in quinolone resistance-determining regions and plasmid-mediated quinolone resistance determinants were identified in 16 and 20 isolates, respectively. BlaCTX-M and a point mutation (C-42T) in ampC promoter were detected in 15 and 8 of the CTX resistant isolates, respectively. In addition, macrolide resistance gene mphA was identified in eight azithromycin resistant O111:H8 isolates and one O26:H11 isolate. Single nucleotide polymorphism analysis demonstrated that the O26 and O157 isolates had multiple origins, but the O111 isolates were closely related. Taken together, our data demonstrated that several sequence types associated with hemolytic uremic syndrome from the retail beef samples in China had developed into dangerous multidrug resistant pathogens. The resistant phenotype can facilitate their transmission among the farm animals and human beings when there is an antimicrobial selective pressure.
Assuntos
Proteínas de Escherichia coli/isolamento & purificação , Microbiologia de Alimentos/estatística & dados numéricos , Carne Vermelha/microbiologia , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , China , Resistência a Múltiplos Medicamentos/genética , Humanos , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Sorogrupo , Fatores de Virulência/genéticaRESUMO
BACKGROUND: Currently, synthetic antioxidants have been widely used to retard lipid and protein oxidation in the meat industry. However, consumers have concerns about these synthetic antioxidants because of their potential toxicological effects. Accordingly, natural antioxidants can be used as a result of their health safety compared to synthetic antioxidants. The present research aimed to assess the protective effects of purslane (Portulaca oleracea L.) extract (PE) against lipid and protein oxidation under chilled storage for 12 days. Rabbit meat patties were divided into five experimental groups: control (without extract), butylated hydroxytoluene BHT (with 0.02% BHT, w/w) and the different concentrations of PE (0.1%, 0.3% and 0.5%, w/w) added to rabbit meat patty labeled as 0.1% PE, 0.3% PE and 0.5% PE groups, respectively. 1,1-Diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity, lipid oxidation and protein oxidation were determined, and kinetic models were employed. RESULTS: PE showed the strongest DPPH and ABTS radical scavenging activity, and the half maximal inhibitory concentrations (i.e. IC50 ) of DPPH and ABTS radicals were 5.112 ± 0.384 and 12.607 ± 2.130 µg mL-1 , respectively. Samples that were treated with PE showed low lipid and protein oxidation. Furthermore, the results of kinetic models indicated that PE could reduce the rates of lipid and protein oxidation. CONCLUSION: PE showed a preservative effect with respect exerting a protective effect against lipid and protein oxidation under chilled storage conditions. Our findings demonstrate the strong potential of PE as a natural antioxidant in meat and meat products. © 2020 Society of Chemical Industry.
Assuntos
Antioxidantes/análise , Conservação de Alimentos/métodos , Conservantes de Alimentos/análise , Lipídeos/química , Carne/análise , Extratos Vegetais/análise , Portulaca/química , Animais , Armazenamento de Alimentos , Oxirredução , CoelhosRESUMO
BACKGROUND: Industrial Fuling Zhacai is pickled by a method summarized as 'three times pickled and pressed', in which raw mustard tubers are subjected to three stages of pickling in different salt concentrations, with a pressing operation at the end of each stage to remove brine. This study used Illumina MiSeq technology and multivariate statistical analyses to investigate microbial community succession during the pickling process and its correlation with Zhacai biochemical indices. RESULTS: A total of 19 phyla, 208 genera, and 295 species of bacteria were identified. Lactobacillus was the dominant genus of bacteria in all three stages and Lactobacillus sakei was the dominant species in the first and second stages. A total of six phyla, 200 genera and 301 species of fungi were also identified. According to a PICRUSt2 prediction, the main functions of the bacterial and fungal communities were carbohydrate and protein metabolism, while alcohol metabolism was also a function of fungi. Nine bacterial genera closely correlated with Zhacai biochemical indices: Acinetobacter, Pseudomonas, Pedobacter, Erwinia, Lactobacillus, Chryseobacterium, Flavobacterium, Duganella, and Paenarthrobacter. Six genera of fungi correlated closely: Penicillium, Cystobasidium, Cladosporium, Plenodomus, Aspergillus, and Simplicillium. All these genera probably originated from the surface microorganisms of raw mustard tuber. CONCLUSION: This study reveals the succession patterns of microbial community structures during the pickling process of industrial Zhacai and infers the core functional flora, providing reference data for Zhacai pickling process control. © 2020 Society of Chemical Industry.
Assuntos
Bactérias/isolamento & purificação , Alimentos Fermentados/microbiologia , Fungos/isolamento & purificação , Microbiota , Mostardeira/microbiologia , Bactérias/classificação , Bactérias/genética , Fermentação , Fungos/classificação , Fungos/genética , MetagenômicaRESUMO
Sorghum dried distiller's grains with solubles (S-DDGS) are distillation extract residues from the ethanol fuel industry. In this experiment, two hundred 42-day-old rabbits were randomly allocated to five experimental diets containing 0 g/kg (control), 75, 150, 225 and 300 g/kg S-DDGS. The experiment lasted for 4 weeks. No difference was found in the average daily feed intake (ADFI; p > 0.05). With increasing sorghum inclusion, the average daily gain (ADG) was linearly (p < 0.001) and quadratically (p = 0.039) reduced, while, conversely, the feed conversion ratio (FCR) linearly (p < 0.001) increased. Increasing the amount of S-DDGS in the diet linearly decreased (p < 0.001) the apparent total tract digestibility (ATTD) of dry matter (DM), organic matter (OM), crude protein (CP) and ash. Carcass weight, carcass yield, heart and liver weights were linearly decreased by an increase in the amount of S-DDGS added to diets (p < 0.001), but no difference was observed between the 0, 75 and 150 g/kg S-DDGS groups (p > 0.05). Serum IL-6, IL-10 and SIgA linearly increased (p = 0.008) with increasing levels of S-DDGS in the diet. Rabbits fed 0, 75 and 150 g/kg of S-DDGS had similar IL-6 and IL-10 levels. Statistically significant differences in SIgA were observed between rabbits fed control diets and feed mixtures containing S-DDGS (p < 0.01). To conclude, S-DDGS can safely be added up to 75 g/kg, to the diet of rabbits. Increasing dietary S-DDGS inclusion may decrease the growth performance, nutrient digestibility and carcass traits, and activate immune responses.
Assuntos
Ração Animal/análise , Composição Corporal/efeitos dos fármacos , Dieta/veterinária , Nutrientes/metabolismo , Coelhos/crescimento & desenvolvimento , Sorghum , Fenômenos Fisiológicos da Nutrição Animal , Animais , Digestão/fisiologia , Masculino , Coelhos/imunologia , Distribuição AleatóriaRESUMO
BACKGROUND: To explore a new method of deep processing and to improve the value of rabbit bone, we prepared a nano-scaled rabbit bone powder by dry ball milling and compared the effect of different particle sizes of rabbit bone powder [fine-scaled (236.01 ± 5.99 µm), superfine-scaled (65.92 ± 1.71 µm), nano-scaled (502.52 ± 11.72 nm)] on the nutritional characteristics, pH, color, water-holding capacity, textural and rheological attributes of rabbit meat batter. RESULTS: The rabbit bone powder significantly affected nutritional characteristics of meat batters; in particular, the contents of calcium were increased, regardless of particle size. Additionally, the rabbit meat batter, which contained 20 g kg-1 nano-scaled rabbit bone, had the lowest centrifugal and cooking losses among the treatments. CONCLUSION: Based on the textural and rheological attributes of the rabbit meat batters, the addition of 20 g kg-1 nano-scaled rabbit bone was the best treatment. This represents an important finding with respect to the deep processing of rabbit bone in the rabbit meat industry. © 2018 Society of Chemical Industry.
Assuntos
Osso e Ossos/química , Aditivos Alimentares/química , Produtos da Carne/análise , Animais , Cor , Culinária , Temperatura Alta , Nanopartículas/química , Pós/química , Coelhos , ReologiaRESUMO
BACKGROUND: Men's active involvement in reproductive healthcare has shown to be positively associated with maternal and child health outcomes. Bangladesh has made appreciable progress in its pursuance of maternal mortality related goals in the framework of the MDGs. However, there remains a lot to be accomplished to realise the long-term goals for which active participation of male counterparts in reproductive care is crucial. Therefore, the objective of the present study was to investigate factors associated with male involvement in reproductive health among Bangladeshi men. METHODS: We used data from Bangladesh Demographic and Health Survey (BDHS) conducted in 2011. Study participants were 1196 married men, aged between 15 and 69 years and living in both urban and rural households. Level of male involvement (outcome variable) was measured based on the responses on knowledge, awareness and practice regarding reproductive health. Chi-square tests and multivariable logistic regression models were performed for data analysis. RESULTS: Out of 1196 participants, only 40% were found to be active about partners' reproductive healthcare. Chi-square test showed significant association between active involvement and ever hearing about family planning (FP) in television, learning about FP through community health events, community health workers and poster/billboard. Results from logistic regression analysis revealed that type of residency [p = 0.004, AOR = 0.666, 95% CI = 0.504-0.879], literacy [secondary/higher education- p = 0.006. AOR = 0.579, 95% CI = 0.165-0.509], learning about family planning from Newspaper [p < 0.001. AOR = 1.952, 95% CI = 1.429-2.664], and television [p = 0.017. AOR = 1.514 95% CI = 1.298-1.886], and having been communicated about family planning by community health workers [p = 0.017. AOR = 1.946, 95% CI = 1.129-3.356] were significantly associated with active involvement of men in reproductive health issues. CONCLUSIONS: Level of male involvement was associated with schooling experience, type of residency and exposure to electronic media. National health policy programs aimed at promoting male involvement in reproductive care should focus on improving knowledge and awareness of reproductive health though community health education programs with a special focus in the rural areas.
Assuntos
Serviços de Planejamento Familiar/organização & administração , Saúde Reprodutiva/estatística & dados numéricos , Educação Sexual/organização & administração , Adulto , Bangladesh , Agentes Comunitários de Saúde/estatística & dados numéricos , Características da Família , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Parceiros Sexuais , População Urbana/estatística & dados numéricos , Adulto JovemRESUMO
To examine the determinants of the health information sharing among rural Chinese chronic patients. Two large population-based surveys in rural China were carried out from July 2011 to April 2012. Data used in this study were second hand and sorted out from the two previous databases. A binary logistic regression analysis was employed to discover the impact of demographic characteristics, level of health literacy, and other factors on respondents' health information sharing behavior. Among the total 1,324 participants, 63.6% share health information with others. Among all significant predictors, those who acquire health information via family and friends are 6.0 times the odds of sharing health information than those who do not. Participants who have more than six household members, with middle and high levels of health knowledge, and who are moderately involved in discussions or settlements of village affairs are also more likely to share health information. The reliance on interpersonal communication channels for health information, household size, the patients' preexisting health knowledge, and their activity in village affairs are crucial determinants for health information sharing among rural chronic patients. A more sophisticated model needs to be established to reveal the complex processes of health information communication.
Assuntos
Doença Crônica/terapia , Comunicação , Disseminação de Informação , Relações Interpessoais , População Rural , China , Participação da Comunidade/estatística & dados numéricos , Estudos Transversais , Características da Família , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Public malaria health promotion is an integral part of the national malaria elimination programme, which was launched by the Chinese government in 2010. However, the public awareness of malaria needs to improve. This study aims to explore the determinants of public awareness of malaria. METHODS: A cross-sectional survey was conducted using stratified sampling method from June 2015 to March 2016. Bivariate logistic regression was performed to explore the association between predictors and malaria awareness in the sample population. The homogeneity of the interaction between group assignment and the degree of knowledge related to malaria among the subgroups was calculated by Cochran-Mantel-Haenszel test. RESULTS: Community media (including bulletin boards of village clinics or township hospitals, newspapers, exercise books, shopping bags, aprons, disposable cups, leaflets and banner advertisements) was the most prominent determinant influencing public awareness of malaria. The probability of having high-degree of knowledge about malaria among participants who received malaria-related information from community media were 3.99 times greater than those who did not (odds ratio 3.99, 95 % confidence interval 3.04-5.25, p < 0.001). Moreover, socio-demographic predictors including age, distance to township hospital, endemic county type, history of suffering from malaria, electronic media, self-assessed household income level, educational attainment and the knowledge about malaria were clearly associated with public awareness of malaria. CONCLUSIONS: Community media played the most important role in public awareness of malaria. However, only a few participants have received malaria knowledge through this media. It suggests that community media was an effective publicity material, which should expand its coverage. Malaria health promotion campaign needs to be aligned with target populations, in particular, people who are under 45 years old and residents (especially in type-3 counties) in remote areas.
Assuntos
Erradicação de Doenças , Conhecimentos, Atitudes e Prática em Saúde , Malária/epidemiologia , Malária/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Feminino , Educação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: Lifestyle diseases could be prevented and controlled by disseminating health knowledge. This study explored the health knowledge awareness and the impact factors of health knowledge awareness, and the way people received health knowledge in western China. METHODS: We undertook a cross-sectional survey in 8 counties, 24 townships and 72 villages from July 2011 to April 2012 in Inner Mongolia, Xinjiang, Chongqing and Qinghai in China. Collected data, which were publicly available, consisted of two parts, namely, socio-demographic information and the 1466 corresponding rural residents' awareness and the approach of health knowledge. Analysis of Variance (ANOVA) was used to explore the impact factors of health knowledge awareness. Multiple linear regressions was then applied to examine the potential predictors of health knowledge awareness. RESULTS: Four predictors-age (negative factor), educational level (positive factor), distance from home to the nearest medical institution (negative factor) and annul disposable household income (negative factor) were in the final liner regression model (p < 0.05). The results showed that awareness of health knowledge associated with risk factors was the highest (58.85%). The highest awareness rate of health knowledge is the title "Whether secondhand smoke is harmful to myself" (69.78%) and the lowest title is "Whether eating with hepatitis B patients will be infected Hepatitis B" (21.69%). The main way to receive health knowledge was traditional way such as doctors (80.45%). About more than half of the residents received health knowledge through television, video, newspaper and magazines (65.78%), family members, neighbors (67.38%) and the village health bulletin boards (53.16%). CONCLUSION: Health knowledge awareness of rural residents was quite low and the way of receiving health knowledge was simple and traditional. One of the critical factors was education level. Direct results showed that lower income families always obtained higher health knowledge level than the rich families. The main way to receive health knowledge was traditional ways. In the process of health education, different means of education should be adopted for different groups so as to achieve ideal effect. Potential interventions may be different from education process which should be adapted to different income level families.
Assuntos
Conscientização , Conhecimentos, Atitudes e Prática em Saúde , População Rural/estatística & dados numéricos , Adulto , Fatores Etários , Idoso de 80 Anos ou mais , China , Estudos Transversais , Escolaridade , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Inquéritos e QuestionáriosRESUMO
The aroma profiles in non-smoked bacon were investigated via GC-O-MS, GC × GC-TOFMS, and GC-IMS. GC-O-MS is advantageous for detecting aldehydes. GC × GC-TOFMS is more sensitive to hydrocarbons and alcohols, while GC-IMS detects a balanced range of categories. Only 9 of the 239 detected volatiles were identifiable by all three methods. Therefore, the combination of all three methods proved to be the most effective way to comprehensively analyze the aroma profiles of bacon. Recombination and omission tests were performed using aroma compounds with a flavor dilution (FD) factor greater than 27; five volatiles were identified as key aroma compounds in non-smoked bacon, including hexanal, (E,E)-2,4-decadienal, 1-octen-3-ol, dihydro-5-pentyl-2(3H)-furanone, and 3-methyl-butanoic acid. Among these, hexanal and 1-octen-3-ol exhibited relatively high FD factors and odor activity values (OAVs), so they were confirmed as the primary contributors. Meanwhile, seven volatiles contributed to the unique aroma of non-smoked bacon in different regions. The difference in the aroma of bacon in different regions is mainly due to the content of various volatiles rather than the type. A comprehensive analysis of the aroma in non-smoked bacon can reveal theoretical information for improving the process and quality control of the product.
RESUMO
Heme proteins and their derivatives play important roles in inducing lipid oxidation to produce volatile compounds during bacon drying. This study investigated the effects of heme proteins and their derivatives (hemoglobin, myoglobin, nitrosylmyoglobin, hemin, Fe2+, and Fe3+) on lipid and volatiles profiles in the washed pig muscle (WPM) model. The results of the study indicated that the inducers primarily caused the oxidation of glycerophospholipids. Furthermore, hemoglobin and myoglobin had the most significant impact, and their potential substrates may include PE (O-18:2/20:4), PE (O-18:1/20:4), PC (16:0/18:1), and PE (O-18:2/18:2). Nitrosomyoglobin has limited ability to promote lipid oxidation and may protect ether phospholipids from oxidation. The analysis of the volatiles in the model revealed that heme proteins and their derivatives have the ability to induce the production of key aroma compounds. The descending order of effectiveness in inducing the production of aroma compounds is as follows: hemoglobin, myoglobin, hemin, and nitrosylmyoglobin. The effectiveness of Fe2+ and Fe3+ is similar to that of nitrosylmyoglobin.
Assuntos
Hemeproteínas , Lipídeos , Animais , Suínos , Hemeproteínas/química , Hemeproteínas/metabolismo , Lipídeos/química , Produtos da Carne/análise , Compostos Orgânicos Voláteis/química , Temperatura Alta , Odorantes/análise , Oxirredução , DessecaçãoRESUMO
The effect of drying on the lipid profiles of the lean (LN) and fat (FT) portions of non-smoked bacon was investigated based on a lipidomic approach. The study identified 989 lipids belonging to 26 subclasses in bacon, with triglyceride and phosphatidylethanolamine being the most abundant. Triglycerides, phosphatidylcholines, and phosphatidylethanolamines were significantly decreased, whereas diglycerides, free fatty acids, and lysophospholipids were increased after drying. TG (16:1/18:1/18:2) and TG (16:0/18:1/18:1) were the primary lipids responsible for the binding of volatiles. Based on VIP > 1 and P < 0.05, 355 and 444 differential lipids were observed in the FT and LN portions, respectively. In total, 26 lipids were screened as key precursors for the production of key aroma compounds of bacon in the FT portion, while 127 were screened in the LN portion. PE (18:0/18:2) is believed to be the primary lipid molecule precursors responsible for the development of aroma in both lean and fat portions. This research has enhanced the comprehension of the generation of key aroma compounds derived from lipid oxidation.
Assuntos
Lipidômica , Produtos da Carne , Odorantes , Oxirredução , Lipidômica/métodos , Odorantes/análise , Animais , Produtos da Carne/análise , Lipídeos/análise , Lipídeos/química , Temperatura Alta , Dessecação/métodos , Manipulação de Alimentos/métodosRESUMO
In this work, the 4D data-independent acquisition (DIA) quantitative strategy was used for differential proteomic analysis of four beef tripe samples from different sources to explore the associations between differentially expressed proteins (DEPs) and meat quality traits. A total of 68 shared DEPs were identified in all comparison groups, which were mainly involved in phosphorylation signaling pathway, peroxisome proliferator-activated receptor (PPAR) signaling pathway, and glucuronic acid pathway. In the correlation analysis between DEPs and quality traits of beef tripe, it was found that 21 proteins were significantly associated with the quality traits in beef tripe, which could be considered as the potential biomarkers of beef tripe quality. This study has successfully uncovered the protein composition of beef tripe for the very first time, which helps to understand the key proteins and biological processes associated with the quality traits of beef tripe from different sources and improve the quality control of beef tripe.
Assuntos
Biomarcadores , Proteômica , Bovinos , Animais , Biomarcadores/análise , Carne/análise , Controle de QualidadeRESUMO
In this study, we aimed to uncover the potential underlying mechanisms of the flavor modulation of Chinese bacon by Staphylococcus. To that end, taste-enhancing S. cohnii WX-M8 and S. saprophyticus MY-A10 screened from Chinese bacon were used to investigate the effects of their individual and mixed fermentations and their synergistic fermentation with Lactobacillus plantarum BL-1 on the sensorial attributes, physicochemical properties, microbial diversity, and volatile compounds (VOCs) of Chinese bacon. Our results revealed that S. cohnii WX-M8 and S. saprophyticus MY-A10 significantly increased a* (redness) and Aw and reduced thiobarbituric acid reactive substances (TBARS) when fermented in a mixture. Moreover, they promoted the formation of esters, aldehydes (especially straight-chain aldehydes), and phenolic compounds through pathways related to amino acid metabolism, enhancing sensorial attributes. While synergistic fermentation with L. plantarum BL-1 resulted in an improved a* (redness) of Chinese bacon, and the increased microbial metabolism of the carbohydrate and lipid metabolic pathways, the increase in TBARS and the higher content of acidic volatiles, led to a change in the composition of the flavor substances. The advantage of co-fermentation of Staphylococci in sensory attributes can be attributed to their capability to metabolize amino acids and associates. These findings provide insights into the role of Staphylococcus as a starter in regulating bacon flavor.
Assuntos
Benzenoacetamidas , Microbiologia de Alimentos , Piperidonas , Carne de Porco , Staphylococcus/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Aminoácidos/metabolismoRESUMO
The impacts of Staphylococcus cohnii, S. saprophyticus and their synergistic Lactobacillus plantarum on the quality and flavor of Chinese bacon were investigated by monitoring the physicochemical characteristics and characterizing metabolites with non-targeted metabolomics. Results showed that S. cohnii could increase the tenderness and decrease the oxidation of muscle, while S. saprophyticus stabilized the springiness and increased the proteolysis. The metabolites produced by the co-fermentation of S. cohnii and S. saprophyticus showed a higher hierarchy, then exhibited the highest hierarchy in synergy with L. plantarum. The promising flavor may be related to the arginine biosynthesis, nicotinic acid and nicotinamide metabolism, and pyrimidine metabolism pathways. Staphylococcus contributed to flavor by promoting the accumulation of di- and tripeptides and activating the amino acid metabolic pathway through arginine metabolism. These findings provide thoughts for understanding the fermentation mechanism of Staphylococcus and the targeted modulation of the flavor of Chinese bacon.
Assuntos
Lactobacillus , Carne de Porco , Fermentação , Staphylococcus , ArgininaRESUMO
Previous studies have demonstrated that Staphylococcus cohnii WX_M8 and S. saprophyticus MY_A10 significantly enhanced the flavor of Chinese bacon in a mixed fermentation. However, due to the complexity of the processing, the contribution of the bacteria is deceptive when investigating only the phenotypic changes at the time of fermentation. In order to clarify the metabolic mechanisms of mixed fermentation, a technological characterization, whole genome and comparative genomics analysis, and metabolites were approached in this study. Results showed that differences in tolerance characteristics existed between WX_M8 and MY_A10. And the genomes of both the two strains consisted of one chromosome and four circular plasmids. Their genome sizes were 2.74 Mp and 2.62 Mp, the GC contents were 32.45% and 33.18%, and the predicted coding genes (CDS) were 2564 and 2541, respectively. Based on the annotation of gene functions and assessment of metabolic pathways in the KEGG database, WX_M8 and MY_A10 strains were found to harbor complete protein degradation and amino acid metabolic pathways, pyruvate and butanol metabolic pathways, and isoleucine metabolic pathways, and their diverse enzyme-encoding genes superimposed the metabolic functions, whereas the alcohol dehydrogenase genes, adh and frmA, achieved complementary functions in the production of esters. Comparative genomics analysis revealed a diversity of encoding genes of aminotransferases and a greater metabolism for sulfur-containing amino acids, aromatic amino acids, and branched-chain amino acids in the mixed fermentation of strains WX_M8 and MY_A10. Metabolites analysis showed that MY_A10 focused on the production of soluble peptides and free amino acids (FAAs), while WX_M8 focused on volatile organic compounds (VOCs), resulting in a significant enhancement of the flavor of Chinese bacon when the two were mixed fermented. This result may provide direction for strains WX_M8 and MY_A10 to be used as starter cultures and targeted to regulate flavor.
Assuntos
Fermentação , Genoma Bacteriano , Genômica , Staphylococcus , Staphylococcus/genética , Staphylococcus/metabolismo , Microbiologia de Alimentos , Staphylococcus saprophyticus/genética , Staphylococcus saprophyticus/metabolismo , Redes e Vias Metabólicas/genética , Produtos da Carne/microbiologiaRESUMO
The objective of this study was to assess the prevalence of diarrhea among under-five children in low-middle-income countries and identify the sociodemographic factors associated with it. Data of 36 countries in sub-Saharan Africa from demographic and Health Surveys (2006-2018) comprising 251 341 mother-child (singleton) dyads were analyzed to estimate the prevalence and various modifiable and non-modifiable risk factors of diarrhea. Occurrence of diarrhea during the last 2 weeks was the outcome variable which was measured by mothers' observation of the condition. The overall prevalence of having diarrhea during last 2 weeks was 18.44% (19.12% among boys and 17.75% among girls). Boys had higher percentage of having diarrhea than girls in all countries except in Libya. The risk ratios of having diarrhea decreased progressively with higher wealth quintiles; the risks of were respectively 7% [RR = 0.93, 95% CI = 0.91; 0.97], 11% [RR = 0.89, 95% CI = 0.86; 0.92] and 18% [RR = 0.82, 95% CI = 0.78; 0.85] lower for households in the middle, richer and richest households. Rural residency was associated with lower risks [RR = 0.95, 95% CI = 0.93; 0.98] and not having access to improved water [RR = 1.05, 95% CI = 1.03; 1.08] and toilet facilities [RR = 0.04, 95% CI = 1.01; 1.07] were associated with higher risks of diarrhea. Regarding children's characteristics, higher age groups, birth order were associated with higher risks and female sex with lower risks. Children with mothers in the higher age groups and with above secondary level education had lower risks, and primary education had higher risks of diarrhea. Meta-analysis of 36 countries revealed a significantly negative association between wealth quintile and diarrhea (Odds ratio = 0.72, 95% CI = 0.69; 0.74). Findings indicate the presence of a significant wealth gradient in the burden of diarrheal diseases among under-five children in sub-Saharan Africa, and underscores the need for paying special attention to the marginalized communities when designing intervention programs.