Effects of Cooking Processes on Protein Nutritional Values and Volatile Flavor Substances of Silver Carp (Hypophthalmichthys molitrix).

Silver carp (Hypophthalmichthys molitrix) is normally cooked at a high temperature. In order to explore the effects of cooking methods on the protein nutritional values and volatile flavor substances of silver carp meat, the meat was fried, roasted and steamed, and its contents were determined in relation to moisture, protein, fat, ash, amino acids and volatile flavor substances. The results show that the moisture content of cooked silver carp can be ranked as follows: raw > steamed > roasted > fried. The protein content order of the four samples can be ranked: fried > roasted > raw > steamed. The ash and the fat contents of the four samples showed similar significant (p < 0.05) differences, in the order of fried > roasted > steamed > raw. The contents of all the amino acids in the fried meat were significantly (p < 0.05) higher than the contents in others, and the frying, roasting and steaming processes improved the umami taste (supported by the increased content of glutamate and aspartate) and the protein nutritional value (supported by the amino acid score, essential amino acid index and protein efficiency ratio) of the silver carp meat. A total of 51 compounds were detected in the fried, roasted and steamed meat. Frying and roasting reduced the fishy flavor of this meat. The odor activity value (OAV) indicated that methanethiol, 1-octen-3-ol and 2-heptanone were the key flavor chemicals in raw meat. Hexanal, propionaldehyde, octanal, nonanal, decanal, 1-octen-3-ol and 2-heptanone were key to the flavor of fried meat. Pentanal, decanal, methyl mercap-tan and 1-octen-3-ol contributed greatly to the overall flavor of the roasted meat. Nonanal, methylmercaptan and 1-octene-3-ol had strong effects on the flavor of the steamed silver carp meat.

Effect of Deep Dormancy Temperature Cultivation on Meat Quality of Crucian Carp (Carassius auratus).

To extend the survival of crucian carp (Carassius auratus) during transportation, the effect of deep dormancy temperature (DDT) cultivation on the crucian carp was investigated by measuring the respiratory rate, survival time, and effect of cooling speed on the meat quality. The results of the respiratory rate and survival time indicated that the DDT of the crucian carp was 1.6 °C. The cooling speed had a significant (p < 0.05) influence on the quality of the crucian carp meat, with a faster cooling speed resulting in a lower pH, L* value, a* value, gumminess, springiness, cohesiveness, stickiness, chewiness, CMP, and UMP content for the crucian carp meat, thus resulting in a lower sensory score for the crucian carp meat. A possible reason for the decrease in the quality of the crucian carp meat is that the faster cooling speed led to a strong stress response and higher anaerobic metabolism in the crucian carp. This can be supported by the contents of the blood glucose and lactic acid in the crucian carp treated with higher cooling speed being significantly (p < 0.05) higher than that of the control. Combining all the results of the cooling speed on the eating quality of the crucian carp meat, a cooling speed of 2 °C/h followed by 1 °C/h was suggested for the survival of crucian carp in transit.

Effect of 4 °C and ice temperature on umami-enhancing nucleotides of conditioned pork.

To study new methods to delay the umami taste attenuation of the conditioned pork, the ice temperature of pork, the content of nucleotides, lactic acid, pyruvate, glycogen, and activity of key endogenous enzymes were determined for the conditioned pork stored at 4 °C and ice temperature. The results indicated that the ice temperature of the pork ham bicipital muscle was -1.4 °C. The content of umami-enhancing nucleotides in pork stored at 4 °C decreased significantly (p < 0.05) with increasing aging time, but all umami-enhancing nucleotides in pork stored at ice temperature were decreased significantly (p < 0.05), but the decrease rates were lower than those in pork stored at 4 °C. A possible reason for this was that the storage temperature influenced the activity of endogenous enzymes and glycolysis. Ice temperature storage was an effective method to inhibit the decrease in umami taste nucleotides in conditioned pork.

Comparison of Nutrition and Flavor Characteristics of Five Breeds of Pork in China.

To characterize the quality of widely consumed pork in China, the chemical compositions and other indexes of five breeds of pork were compared. The results indicated that the moisture content, sensory flavor, and overall acceptability of Pipa pork (PPP) were superior to other breeds. The fat content and essential amino acids (EAA) of Yihao native pork (YNP) were significantly (p < 0.05) higher than in other breeds. The protein content, the total amount of amino acids, and perceptible flavor of Tibetan black pork (TBP) were higher than in other breeds. The protein nutrition profiles of manor black pork (MBP) and TBP were better than in others. The equivalent umami concentration (EUC) value of white pork (WP) was significantly (p < 0.05) higher than in others; however, the health risk of its fatty acid content was higher. There were unique protein and flavor chemicals in YNP, TBP, and PPP, which may be useful for distinguishing their authenticity.

Storage Stability and Flavor Change of Marinated Pork.

To evaluate the storage stability and flavor changes of marinated pork treated with chili and pepper essential oils, the contents of total sulfhydryl, malondialdehyde, total volatile base nitrogen (TVBN), Ca2+ATPase activity, and total viable counts of marinated pork were determined. Further, the non-volatile (umami, numb, and spicy) and volatile flavor compounds of marinated pork were analyzed. Based on the results, the chili and pepper essential oils had limited effects on the storage stability of marinated pork. However, these essential oils could inhibit the oxidation of lipids and proteins and reduce the number of microorganisms and TVBN in marinated pork within 6 days. The non-volatile flavors of the marinated pork decreased as the refrigeration time increased. It was concluded that the decomposition of umami-enhancing nucleotides (GMP, IMP, XMP), the number of flavor substances (hydroxyl-α-sanshool, hydroxyl-ß-sanshool), and spicy (capsaicin) tasting compounds caused the decrease in non-volatile flavors.

Fiber Protein Produced in Escherichia coli as a Subunit Vaccine Candidate Against Egg-Drop Syndrome 76.

The egg-drop syndrome '76 (EDS '76) caused by duck atadenovirus A (DAdV-1) infection in laying hens leads to the decrease in egg production, causing heavy economic losses in the poultry industry; thus, vaccines with high safety and immunogenicity are needed. In this study, the DAdV-1 fiber protein expressed in Escherichia coli with codon optimization showed the hemagglutination (HA) titer of 13 log2 after purification (0.6 mg/mL). Compared with inactivated EDS '76 vaccine, the specific pathogen-free chickens immunized with 0.4 mL fiber protein (HA titer of 11 log2) induced an equal level of HA inhibition (HI) titer and neutralizing antibodies. Meanwhile, after immunization with fiber protein, the lowest HI titer that could provide the effect to reduce egg production rate in laying hens after the challenge was 7 log2. Moreover, fiber protein with an HA titer of 7 log2 could induce an HI titer no <7 log2 in laying hens, which was equal to or higher than the lowest HI titer (7 log2) that could reduce egg production against DAdV-1 infection significantly, indicating that it is economically feasible for vaccine development. Importantly, the HI antibodies maintained at a high level up to 180 days postimmunization contribute to the clinical application of the vaccine candidate. Overall, the fiber protein produced in E. coli is an effective subunit vaccine candidate in EDS '76 control for its high immunogenicity and protection in chickens.

A metabolomic signature of FIGO stage I and II endometrial cancer.

Endometrial cancer (EC) is a malignant tumor of the female reproductive tract. Due to its rapid growth and invasiveness, EC is currently the only gynecological neoplasm with rising incidence and mortality rates. It is of great significance to explore the metabolomics signature of stage I and II EC for the diagnosis and treatment. A mass spectrometry-based untargeted metabolomics approach was used to explore preoperative serum metabolites in the normal and stage I and II EC patients. The metabolites were mapped to the Ingenuity pathway analysis (IPA) database to determine the potential biomarkers and metabolic pathways that differ between EC patients and healthy controls. The top analysis-ready molecules of upregulated D-glucose thiamine and downregulated cholesterol, arachidonic acid, palmitic acid, oleic acid, stearic acid, linoleic acid may be the most related metabolites. These potential biomarkers have essential functions in regulating vital metabolic pathways associated with stage I and II EC. Additionally, our pathway analysis revealed five significantly related pathways according to the metabolite differentials. Finally, the disease and function prediction of the initial pathway analysis suggested that small molecule biochemistry, lipid metabolism, and organismal injury and abnormalities were associated with EC cases. Over 25 metabolites were differentially expressed in stage I and II EC. In addition, the six most significant metabolites were related to stage I and stage II EC cases. Ingenuity pathway analysis revealed potential biomarkers and metabolic pathways revolved to EC. In this paper, candidate endogenous biomarkers were defined as the basis for disease diagnosis and individualized treatment monitoring and revealed the mechanism of EC occurrence and development.

Utility of serum amyloid A as a potential prognostic biomarker of acute primary basal ganglia hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) can lead to inflammation. Serum amyloid A (SAA) is an acute phase protein, which might be implicated in acute brain injury. We ascertain relationship between serum SAA and inflammation, severity plus outcome after ICH. METHODS: In this prospective, observational study, serum SAA concentrations were quantified in 159 healthy volunteers and 159 acute primary basal ganglia hemorrhage patients admitted within 24 h after stroke symptom. Prognostic parameters included death and a poor outcome (modified Rankin Scale score > 2) at 90 days after stroke. RESULTS: Serum SAA concentrations were substantially higher in patients than in controls. Among patients, serum SAA concentrations were strongly correlated with serum C-reactive protein concentrations, hematoma volume and National Institutes of Health Stroke Scale scores. Serum SAA appeared to be an independent predictor for 90-day death, overall survival and poor outcome. Under receiver operating characteristic curve, this protein exhibited similar prognostic capability, as compared to hematoma volume and National Institutes of Health Stroke Scale scores. CONCLUSIONS: Rising serum SAA concentrations, in close correlation with inflammation and hemorrhagic severity, are independently related to mortality and poor outcome after ICH, indicating that serum SAA might serve as a potential prognostic biomarker for ICH.

Serum tenascin-C predicts severity and outcome of acute intracerebral hemorrhage.

BACKGROUND: Tenascin-C is a matricellular protein related to brain injury. We studied serum tenascin-C in acute intracerebral hemorrhage (ICH) and examined the associations with severity and outcome following the acute event. METHODS: Tenascin-C samples were obtained from 162 patients with acute hemorrhagic stroke and 162 healthy controls. Poor 90-day functional outcome was defined as modified Rankin Scale score > 2. Early neurological deterioration (END) and hematoma growth (HG) were recorded at 24 h. RESULTS: Patients had higher tenascin-C levels than controls. Tenascin-C levels were positively correlated with hematoma volume or National Institutes of Health Stroke Scale score at baseline. Elevated tenascin-C levels were independently associated with END, HG, 90-day mortality and poor functional outcome. Moreover, tenascin-C levels significantly predicted END, HG and 90-day outcomes under receiver operating characteristic curves. CONCLUSIONS: An increase in serum tenascin-C level is associated with an adverse outcome in ICH patients, supporting the potential role of serum tenascin-C as a prognostic biomarker for hemorrhagic stroke.

Dynamic distribution and tissue tropism of infectious laryngotracheitis virus in experimentally infected chickens.

Infectious laryngotracheitis (ILT), caused by infectious laryngotracheitis virus (ILTV), is an Office International des Epizooties (OIE) notifiable disease. However, we have not clearly understood the dynamic distribution, tissue tropism, pathogenesis, and replication of ILTV in chickens. In this report, we investigated the dynamic distribution and tissue tropism of the virus in internal organs of experimentally infected chickens using quantitative real-time polymerase chain reaction (qPCR) and a histopathological test. The study showed that ILTV could be clearly detected in eight internal organs (throat, trachea, lung, cecum, kidney, pancreas, thymus and esophagus) of infected chickens, whereas the virus was difficult to detect in heart, spleen, proventriculus, liver, brain and bursa. Meanwhile, the thymidine kinase (TK) gene levels in eight internal organs increased from 3 days to 5 days postinfection, and then decreased from 6 days to 8 days postinfection. The log copy number of ILTV progressively increased over 3 days, which corresponds to the clinical score and the result of the histopathological test. The results provide a foundation for further clarification of the pathogenic mechanism of ILTV in internal organs and indicate that throat, lung, trachea, cecum, kidney, pancreas and esophagus may be preferred sites of acute infection, suggesting that the tissue tropism and distribution of ILTV is very broad.

Rapid detection of infectious laryngotracheitis virus isolates by loop-mediated isothermal amplification.

The objective of this study was to develop and evaluate a loop-mediated isothermal amplification (LAMP) method to detect infectious laryngotracheitis virus (ILTV) from commercial broiler and layer flocks in southern China. A set of six specific primers was designed to recognize six distinct genomic sequences of thymidine kinase (TK) from ILTV. The entire assay duration was recorded at 40 min under isothermal condition at 63.5 degrees C. The amplified products were analyzed by electrophoresis and visual judgment by the SYBR Green I dyeing. LAMP assay was 10-fold more sensitive than the routine PCR assay, with a detection limit of 46 copies per reaction. In detecting ILTV, the LAMP assay detected all 5 strains previously isolated, did not cross-react with other avian pathogens, and obtained a 100% sensitivity in 43 positive clinical samples with reference to virus isolation. Therefore, the LAMP assay may be a good alternative method for specific diagnosis of ILTV infection in primary care facilities, and in less well-equipped laboratories.