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Fish protein hydrolysates (FPHs) were prepared from freshwater carps (Catla catla, Labeo rohita, and Cirrhinus mrigala) using flavorzyme at different degrees of hydrolysis (DHs) ranging from 5 to 20%. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of the FPHs prepared from the three species were in the range of 50–82%; the ferric reducing power of the FPHs prepared from catla was the highest. The linoleic acid peroxidation inhibition activity of the prepared FPHs varied from 71 to 91%. The emulsion activity index of the FPHs prepared from catla and rohu decreased significantly with an increase in the DH (p < 0.05). The emulsion stability index of the FPHs prepared from the three species was the highest at 20% DH. FPHs prepared from freshwater carps possess good antioxidant and surface-active properties and are therefore suitable to be used as natural antioxidants in health-food formulation and as water-soluble antioxidants in the food-processing industry.

Typical solvent extraction of succinic acid from a chitosan-succinic acid powder mixture gave unsatisfactory yield (10.0%) due to the presence of intramolecular crosslinks between the chitosan amine groups and succinic acid carboxylic groups. An improved extraction method, which included hydrolysis of cross-links by KOH to liberate succinic acid from the matrix, afforded satisfactory yield (95.2±4.0%). Quantitative analysis of succinic acid in chitosan-succinic acid mixture was performed using GCMS and the optimized analysis method showed good validation in terms of specificity, linearity, accuracy (recovery rate), precision (inter-day and intra-day precision), limit of quantification (LOQ), and limit of detection (LOD).

Possibility of photostimulated luminescence (PSL) and electron spin resonance (ESR) to detect γ-irradiation of jujube (Zizyphus jujuba) was investigated. The jujube samples were exposed to γ-irradiation at doses of 1, 3, 5, and 10 kGy. The PSL results showed that jujube exposed to at 1 kGy or more had a photon count of greater than 5,000 count/60 sec (positive), while the non-irradiated jujube yielded a photon count of less than 700 photon count/60 sec (negative). However, physical parameters (light exposure, storage, and thermal treatment) of irradiated jujube samples gave a strong effect on the PSL signal, resulting in decrease of the photon counts from the initial counts. ESR spectroscopy analysis of irradiated jujube revealed specific signals derived from cellulose radicals, and irradiation caused a significant increase in the ESR signal intensity of the jujube samples without any changes in the spectral patterns. Light exposure, storage, and thermal treatment of jujube resulted in significant decreases in the ESR signal intensities of cellulose radicals.

Changes in physicochemical properties, metabolite production, antioxidant activities, and survival of Lactobacillus casei 431 in a yogurt drink as a function of inulin (0, 0.5, 1, and 2%), pomegranate juice concentrations (0, 3, 8, and 12%) and storage time were determined and predictive models were obtained using support vector regression. High levels of pomegranate juice were the most effective for promotion of antioxidant activity. Acidity and lactic acid amounts decreased with an increasing inulin content. Supplementation with inulin and pomegranate juice showed a positive effect on survival of L. casei. Support vector regression performance associated with polynomial and radial basis kernel functions was evaluated. The former was more efficient than the later.

The aim of this study was to investigate what kind of stress vitamin C could alleviate. Experiments were performed using male ICR mice. Vitamin C (1, 5, 25, and 100 mg/kg) was administered orally daily for 7 days without stress and then were given for 5 days with electroshock (ES) or restraint stress (RS). After loading final stress, we recorded stress-related behaviors and measured the levels of blood corticosterone. Vitamin C supplementation (25 and 100 mg/kg) partially blocked stress-related behaviors such as freezing, smelling, burrowing, facewashing, and grooming. It decreased also staying time in closed arms. Stress responses induced by ES but not immobility were also significantly alleviated by vitamin C. Vitamin C (25 and 100 mg/kg) decreased corticosterone level increased by ES. Swimming time in cold water (8±2°C) was not changed by vitamin C, but crossing frequency in the electric field was increased by vitamin C (25 mg/kg). These results suggest that vitamin C supplementation can prevent damages or diseases induced by stress, especially psychological stress.

To evaluate the microbiological safety of Korean traditional seasoned beef processed by sous-vide method, Clostridium perfringens spores were inoculated into the samples, and then germination and growth of spores were observed under different temperatures for days. Also, changes in pH, water activity, and salt contents were analyzed. As the results, there was no difference in water activity and pH of the samples during the storage at any temperature. However, salt contents of the samples significantly increased as storage time increased, and the storage temperature affected the change of salt contents. C. perfringens did not grow at 4 and 10°C for 24 days however, the bacterial growth was observed at 20°C after 2 days of storage. Based on these simulation tests, the microbiological safety of sous-vide processed galbijjim can be guaranteed at 4 and 10°C for 24 days even though the raw materials were contaminated by C. perfringens spores.

This study was conducted to investigate whether the white lotus extracts could enhance the pentobarbital-induced sleeping behaviors and chloride influx, as well as have an antioxidant function. When accessing the effect on sleeping behaviors, extract from the dried mature leaf (DML) increased sleeping time more than twice compared with the control group. Also, the DML extract increased chloride influx in primary cultured cerebellar granule cells. The antioxidant function of white lotus extracts derived from young leaf, DML, and ovary had similar performance when being compared to ascorbic acid. The result suggested that white lotus extracts could contain components that are able to potentiate pentobarbital-induced sleep behaviors and to activate chloride channel, as well as antioxidant function.

Tea is one of the most widely consumed aromatic beverages in the world because of its taste and flavor, as well as due to many potential health beneficial properties. Metabolomics focuses on an in-depth analysis of all metabolites in living organisms. In this study, 29 primary metabolites and 25 secondary metabolites were identified using GC/MS and UPLC-QTOF/MS, respectively. Further, PCA analysis showed conspicuous discrimination for the ten varieties of green tea with metabolite profiling. Among them, organic acids, amino acids, flavan-3-ols, and flavonol glycosides varied greatly through checking the VIP values of the PLS-DA model. Moreover, the intrinsic and/or extrinsic factors characterizing each type of green tea were also discussed. The chemical component marker derived here should be used as an important detection index, while evaluating the tea quality, as well as while establishing the tea quality standard.