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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.

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.

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-β-sanshool), and spicy (capsaicin) tasting compounds caused the decrease in non-volatile flavors.

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.

Ginkgolic acids are unwanted constituents in standard Ginkgo biloba leaves extracts. Thus, for the quality control of ginkgo extracts, it is important to establish an effective degradation method, with high catalytic efficiency and safety, to remove ginkgolic acids. Laccases are oxidases with potential for application in elimination of hazardous phenolic compounds. In this study, single-factor and orthogonal experiments were used to optimize extraction of ginkgolic acid from G. biloba sarcotestae. The results showed that ethanol was the best solvent, with the highest extraction rate for ginkgolic acid at 85% ethanol. On this basis, we measured ethanol volume fraction, extraction time, temperature and solid-liquid ratio using an orthogonal experiment. By using absorbance of 310 nm as standard, the optimal extraction conditions were 85% ethanol with, solid-liquid ratio of 1:14 at 40°C for 12 h. These conditions gave a ginkgolic acid yield of 73.1 mg·g−1. Subsequently, recombinant laccase was used to degrade the ginkgolic acid in several laccase/mediator systems, of which LacC was the best. At 50°C, pH 4.5, enzyme concentration of 0.01 U·mL−1, 0.5 mmol·L−1 mediator ABTS and reaction time of 3 h, the degradation rate of ginkgolic acid reached 100%. These results lay the foundation for research on and application of biological enzymes for detoxification of G. biloba extracts.

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.