Abstract: Acrylamide, a potential carcinogen and neurotoxin, could be formed during the heat processing of carbohydrate-rich foods under high temperatures. Maillard reaction between reducing sugars and amino acids is the main pathway to form acrylamide. All of the types of reducing sugars and amino acids as well as the addition of vitamins may influence the formation of acrylamide. To explore the influence of reducing sugars, amino acids and the addition of vitamins on acrylamide formation, different chemical model systems were designed and studied in this work. The results showed that the largest amount of acrylamide was produced in the asparagine/glucose model system. L-glycine, L-glutamic acid and L-cysteine caused different levels of reduction in the amounts of acrylamide produced in the asparagine/glucose model systems. Vitamin C and Vitamin B₁ strongly reduced the formation of acrylamide by more than 60% at the appropriate adding dosage of approximately 1%, whereas Vitamin B₂ and Vitamin B₅ only reduced the formation of acrylamide by 20-30% at the adding dosage of approximately 1%. However, Vitamin B₂ promoted the formation of acrylamide at adding dosages greater than 1%.

Abstract: The Zanthoxylum bungeanum leaf has been traditionally taken as a vegetable and seasoning in . To disclose the mechanisms of its benefit for human health, antioxidant activity and cytoprotective effect of the leaf were investigated. The ethyl acetate fraction exhibited the strongest ABTS and DPPH radicals scavenging activities as compared with chloroform and water fractions, as well as the crude extract. This fraction exhibited a protective effect against hydrogen peroxide-induced cytotoxicity in PC12 cells by MTT reduction assay. Furthermore, the cytoprotective effect was confirmed using flow cytometry analysis. Comparing with the model cells, the ethyl acetate fraction significantly increased G0/G1 and G2/M phase cells together with reducing S phase cells. Ten flavonoid glycosides were identified as isovitexin, vitexin, hyperoside, rutin, isoquercitrin, foeniculin, trifolin, quercitrin, astragalin, and afzelin from this fraction using high performance liquid chromatography-tandem mass spectrometry and nuclear magnetic resonance spectroscopy. This is the first report for the presence of vitexin, isovitexin, astragalin, trifolin and afzelin in Z. bungeanum. Hence, the results present here suggest the potential utility of Z. bungeanum leaf as a source of natural antioxidant due to its diversity and high content of flavonoids.

Abstract: This paper aims to explore the effect of soybean trypsin inhibitor（STI） on oxygen free radicals levels in pancreatic mitochondria of mice. 36 male KM mice were randomly divided into three groups and fed with different diets as follows: control group was fed on control diet, STI group was fed on control diet containing STI, and VC (vitamin C) group was fed on STI diet supplemented with vitamin C. Mice were sacrificed by decapitation after being fed for 3 weeks. Pancreas was quickly removed and mitochondria were prepared for determining the oxidative and antioxidative index. The results showed that, compared with mice fed with control diet, malondialdehyde (MDA) content and activity of nitric oxide synthase (NOS) in pancreatic mitochondria of mice fed with STI diet were significantly increased (P < 0.05), the content of glutathione (GSH), total antioxidant capacity (T-AOC), the activities of glutathione peroxidase (GSH-Px), catalase(CAT) and superoxide dismutase (SOD) were significantly dropped. After STI diet was supplemented with antioxidant, the contents of oxidation parameters were significantly decreased (P < 0.05), but their values were still higher than those of control group; the activities of antioxidant parameters in pancreatic mitochondria were significantly increased (P < 0.05), but still lower than those of control group. These results supported that STI could cause oxidative stress in pancreatic mitochondria. In addition, vitamin C could interfere with the role of STI on the organism and effectively improve the status of oxidative stress.

Abstract: A real-time turbidimeter loop-mediated isothermal amplification (LAMP) assay was developed for the rapid, sensitive, and convenient detection of genetically modified (GM) ingredients in soybean products obtained from local supermarkets in China. Specific primers were designed based on the published sequence of lectin, nos terminator and endogenous genes of two GM soybean strains (GTS40-3-2 and MON89788). The total genomic DNA of soybean-made products was extracted by cetyltrimethylammonium bromide (CTAB) method. Then, the genomic DNA was used as template for LAMP assay. The results showed that this real-time turbidimeter LAMP assay was specific and sensitive enough to amplify DNA from soybean products. The limit of detection (LOD) of lectin and MON89788 was 0.01% (weight of GM soybean/weight of non-GM soybean), roughly equivalent to four copies of soybean genomic DNA in DNA mixture within one hour; and the LOD of nos and GTS40-3-2 was 0.1%, roughly equivalent to forty copies of soybean genomic DNA within 1 hour. The sensitivity reaches to 0.01%, which meets the requirements of the European Union (EU). In practical application, the total detectable ratio in soybean-made products was the same as that of PCR, suggesting that LAMP method was accurate and sensitive.

Abstract: In present study, a method basing on accurate mass and fragmentation pattern was designed to screen the terpene lactones and flavonoids in the methanol extract of Ginkgo biloba capsule powder. An UPLC with a hybrid linear ion trap – orbitrap mass spectrometer (UPLC-LTQ-Orbitrap Elite) was used. The chromatographic analysis of the sample was performed on a C₁₈ column (100 × ID, particle size 1.9 μm) with gradient elution using methanol and water with 0.10% formic acid. Mass spectrometry was performed in the negative ESI mode. By comparison the accurate mass, element composition and fragment pattern, twenty-six compounds were identified, including 5 ginkgo terpene lactones (bilobalide, ginkgolide A, B, C and J) and 21 flavonoid glycosides. The major glycosides identified included: kaempferol-3-O-glu-glu-rha, kaempferol-7-O-rutinoside, isorhamnetin-3-O-rutinoside, kaempferol-3-O -rha-glu, quercetin-3-O- glucoside, kaempferol-3-O-rha-glu-coumaroyl and -methoxymyricetin-3-O-rutinoside. The structural isomers were differentiated through the characteristic ions obtained from their MS/MS spectra. In addition, a compound 3,5,-trihydroxyflavone-3-O-glucoside, which was not reported in G. biloba before to our knowledge, was identified in the extract. The fragmentation pathways and characteristic product ions of flavonoid glycosides were shown and summarized for the rapid identification. The developed method was proved to be useful and precise for fast qualitative analysis of flavonoid compounds in mixture.

Abstract: Corynebacterium species occur as part of the normal flora of animals and humans and there is very little information on the diversity and host range of these pathogens. Despite this, some Corynebacterium species have been reported to cause infections in both animals and humans. Infections usually result from the consumption of contaminated food products such as meat and milk as well as contact with infected animals. The aim of study was to isolate, identify and characterize Corynebacterium species from retail meat products obtained from some supermarkets in the North West Province, South Africa. A total of 25 mutton and lamb meat samples were purchased from some supermarket and butcheries in the North West Province, South Africa and bacteria was isolated using Colombia agar supplemented with 5% (w/v) bovine blood. Seventy five presumptive Corynebacterium isolates were obtained based on colonial morphology and these isolates were screened for characters of Corynebacterium species. Amongst these, 67 isolates were catalase positive while 54 were Gram positive rods. Twenty four representative isolates were not able to utilize urea and ferment glucose and maltose respectively. However 19 (79.2%) of these isolates were able to utilize nitrate and33% were positively identified as Corynebacterium species using API Coryne assay. Eleven percent of the isolates were positively identified as Corynebacterium species by 16S specific rRNA PCR analysis. From these results it was evident that Corynebacterium species were present in the raw meat products and the meat products could pose severe health risks to consumers, especially individuals who are immuno-compromised. This therefore amplifies the need to implement strict measures that limit the transmission of these pathogens through the food chain to consumers. Moreover, constant assessments of the health risks associated with contaminated food products in the South African market should be performed on routine basis.

Abstract: Garlic is a vegetable known to be a good antioxidant food resource around the world. Several studies on the antioxidant activity of garlic, mainly conducted using one or two methods, have been reported. However, comparison of the antioxidant activity of garlic before and after cooking is rarely reported. In this study, we compared the antioxidant activity of garlic aqueous and methanol extracts processed before and after boiling to mimic the cooking process. By testing the antioxidant activities of the extracts in different chemical mimic systems in vitro, namely, ABTS [2, 2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid)] and DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging activities, reducing power, and metal chelating ability, we found the following data: (1) no significant difference was observed on the ABTS radical scavenging activities of garlic aqueous and methanol extracts before and after boiling process; (2) the reducing power of garlic aqueous and methanol extracts decreased by 25.9% and 14.1%, respectively, whereas the metal chelating activity of boiled garlic aqueous extracts increased by 54.7%; and (3) DPPH radical scavenging test may not be suitable to examine the garlic extracts. In addition, the ABTS radical scavenging activities of garlic extracts were very stable at pH ranges similar in human bodies, and both sulfhydryl and phenolic compounds were probably responsible for the antioxidant ability of garlic. The boiling process destroyed only a small part of garlic bio-ingredients related to antioxidant activity properties.

Abstract: Owing to the favorable effects of essential fatty acids on human health, a great degree of interest on fatty acid profiles and nutritional quality of fish species have been of interest in the recent years. The present study investigated the lipid content, fatty acid profiles and nutritional quality in nine freshwater fish species from the Ganjiang River in the Yangtze basin, China. Results showed that total lipid content of the dorsal muscle was 0.59–2.2% and that was inversely linked to moisture content (r² = 0.79, p < 0.01). Wide ranges of monounsaturated fatty acids (MUFA) (21.83 to 50.53%) and polyunsaturated fatty acids (PUFA) (19.43 to 45.60%) were found. The ratios of n-3 to n-6 PUFA ranged from 0.25 to 1.16 (p < 0.001). N-3 PUFA was dominated by eicosapentaenoic and docosahexaenoic acids varying from 2.77 to 15.11% of total fatty acids. Indices of atherogenicity and thrombogenicity (IA and IT) based on fatty acid compositions ranged from 0.36 to 0.52 and 0.36 to 0.64 in all species, respectively (p < 0.001). These results indicated fatty acid profiles were different among the fish species and the potential of these species as dietary source of essential fatty acids from the nutritional standpoint.

Abstract: This study aimed to characterize the effect of jasmonic acid (JA) on volatile compounds in grains of Kam sweet rice. Using GC-O and SPME-GC-MS, nonanal displayed the highest odor activity value (OAV) in the filling grains and increased after applicaton of jasmonic acid in the rice seedlings. The relative expression of rice OsLOX3 (rice lipoxygenase 3) and OsHPL1 (rice hydroperoxide lyase 1) was assessed by RT-PCR in Kam sweet rice Gou Cengao and the non-aromatic Kam rice Lailong rice after rice pollination. Our data showed that OsLOX3 was elevated in Gou Cengao compared with the non-aromatic rice. In agreement, lipoxygenase (OsLOX3 gene product) levels and activity were elevated in aromatic rice samples. The positive Pearson correlation (0.715) was found between JA and lipoxygenase activity (p < 0.01). Interestingly, a significant positive Pearson correlation (0.936) was found between the concentrations of endogenous JA and the relative expression of rice OsLOX3 (p < 0.01). The results suggest that the enhancing effect of JA on the biosynthetic pathway of nonanal.

Abstract: In this study, three extraction methods of polysaccharides in Purslane were compared and analyzed, and the best method was ascertained. Purslane polysaccharides were extracted using water, ultrasonic and microwave. By the results of single factor experiments and orthogonal experiments, the optimal extracting conditions were selected and then the best extraction method was determined. In order to calculate the extraction yield of polysaccharides, its content were measured by the phenol–sulfuric acid method using glucose as the standard, and then the efficiency of three extraction methods was evaluated. The results showed that the extraction yield of ultrasonic was 35.42% under the optimal conditions of 60C, 60 min, 1:20 and 200w. The extraction yield of microwave method was 32.12% under the optimal conditions of 3 min, 1:25 and 500w. The extraction yield of water method was 31.22% under the optimal conditions of 80C, 2 h, 1:30 and 3 times. It could be concluded that ultrasonic method was the best one in these three methods.