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Photostimulated luminescence (PSL), thermoluminescence (TL), electron spin resonance (ESR), and direct epiflourescent filter technique/aerobic plate count (DEFT/APC) were applied to detect dried green, black, and oolong teas irradiated between 0-10 kGy. Teas irradiated at 2.5 kGy and higher showed over 5000 photon counts/60 sec, while non-irradiated teas yielded 650-1000 photon counts/60 sec. TL glow curves for minerals separated from teas were detected at about with low intensity in non-irradiated samples, whereas around with high intensity in all irradiated samples. Ratio of based on re-irradiation step, showing lower than 0.1 and higher than 1.44 for non-irradiated and irradiated samples, respectively, enhanced reliability of TL results. ESR measurements for irradiated teas showed signals specific to irradiation. Log DEFT/APC ratio increased with irradiation dose; this result could be applied to identify irradiated tea samples.

Optimal extraction conditions such as pressures, temperatures, and modifiers on glycyrrhizin extraction from licorice were investigated using supercritical CO2 (SC-CO2) at 3 mL/min flow rate. Morphology of licorice tissue, after glycyrrhizin extraction, was examined by SEM, and absolute density (g/cm3) measurement and glycyrrhizin content were determined by HPLC. Pure SC-CO2 had no effect on glycyrrhizin extraction, but recovery of glycyrrhizin (32.66±0.77%) was enhanced when water was used as modifier. The highest recovery was 97.22±2.17% when 70% (v/v) aqueous methanol was added to 15% (v/v) SC-CO2 at 50 MPa and 60℃. Under optimal extraction conditions, 30 MPa pressure and 60℃ heating temperature, glycyrrhizin recovery reached maximum (102.67±1.13%) within 60 min. Licorice tissue was severely damaged by excessive swelling, and absolute density of licorice residues was highest when aqueous methanol was used as a modifier.

Dynamic shear moduli of isolated soy protein solutions upon heating were measured to monitor gelation. Onsets of gelation coincide with onset temperatures of denaturation in glycinin and B-conglycinin solutions, whereas in isolated soy proteins, onset of gelation was above denaturation temperature of B-conglycinin with storage modulus increasing in two steps. The first increase in storage modulus of isolated soy proteins occurred at about 78.5℃, while the second increase started at about 93℃. Gel properties of soy protein gels having different proportions of glycinin and B-conglycinin were measured by compression-decompression test. B-conglycinin was responsible for gel elasticity. Glycinin significantly increased hardness, toughness, and fracturability of gels at high heating temperature near 100℃. Results reveal texture of soy protein gels can be controlled by regulating ratio of glycinin to B-conglycinin and heating temperature.

Additions of ground garlic, chili and ginseng powder did not affect the breaking force and strain of directly heated gel of Alaska pollack surimi. In comparison, these additives reduced the setting effect achieved by incubation of the salted surimi at 25℃, and resulted in a decreased breaking force and strain for the two step heated gel. Garlic almost completely inhibited the myosin cross-linking reaction, an important reaction for improving the gel properties occurring in the setting process. However, chili and ginseng powder minimally inhibited the cross-linking reaction. Thus, this study proposes that the mechanism for the suppression of the setting effect by chili and ginseng is different from that of garlic.

To improve Dongchimi (watery radish kimchi) quality and preservation, 0, 3, 5, 10, and 15% of gatt (Brassica juncea; leaf mustard) per radish was added. Chemical characteristics were determined during fermentation at 10℃ for 45 days. Total acidity increased slowly by addition of gatt during initial fermentation period, and 15% treatment showed lowest total acidity. Total vitamin C content increased initially in all treatments depending on gatt content, and decreased thereafter. Period for reaching maximum value was delayed by addition of gatt. Highest total vitamin C was found in 15% treatments. In the case of reducing sugar, 5% treatment showed highest contents. Lactic, succinic, and tartaric acid contents consistently increased during fermentation, while those of malic and citric decreased. Turbidity and total solid contents of Dongchimi liquid increased in all treatments as fermentation proceeded, although the extent was rather suppressed by addition of gatt. Colorimetric lightness values decreased, while the initial increased and then decreased in redness and yellowness. Addition of gatt at above 15% weight level per radish accelerated fermentation at the later fermentation stage thus it should be avoided. Most changes in typical characteristics of fermentation were similar depending on treatments. More acceptable Dongchimi could be prepared by fermenting at 5% gatt concentration under given conditions.

To extract apple pectins, apple pomace (AP) was extruded under 14 different conditions of screw speed (250-350 rpm), feed rate of 30-40 kg/hr, and 20-30% moisture content using twin-screw extrusion. Response surface methodology (RSM), based on three variables by three-level factorial design, was employed to investigate effects of screw speed, feed rate, and moisture on dependent variables of extrudates, soluble dietary fiber (SDF), yield of anhydrogalacturonic acid (Y AGA) representing pectin, and intrinsic viscosity ([]). Second order models were used to generate three-dimensional response surface for dependent variables, and their coefficients of determination (R2) ranged from 0.96 to 0.99. Moisture content showed highest effect on solubilization of AP.

Effects of acid and a-amylase on resistant starches including retrograded RS3 and cross-linked RS4 prepared from normal maize starch were investigated. Acid and a-amylase hydrolytic patterns of RS3 were similar, while those of native starch and RS4 differed. Acid hydrolysis rate of RS3 was markedly higher at initial stage, then slowly decreased up to 20 days, whereas that of RS4 increased continuously. The sizes of acid- and a-amylase-treated RS3 residues decreased, but those of RS4 remained unchanged. X-ray patterns of all treated residues did not change; however, the peak intensities increased. Swelling power of RS3 increased to 150% at 95℃, whereas that of RS4 differed depending on the treatment condition. Swelling power of acid-treated RS4 residue increased markedly, but that of a-amylase-treated one remained constant. Gel filtration chromatography profiles of untreated RS3 and RS4 residues were similar, whereas that of acid-treated RS4 residue was different from them. RS showed different hydrolytic behavior by acid and a-amylase depending on the type, and susceptibility of RS3 was higher than that of RS4.

Four compounds were isolated from the rhizome of Belamcanda chinensis (Iridaceae) by repeated column chromatography and were elucidated as iristectorigenin A, irigenin, tectorigenin and tectoridin by spectral analysis. The estrogenic activity of these isoflavones was tested using Ishikawa cells. Irigenin, tectorigenin and tectoridin were highly estrogenic (￡C50 = 0.75, 0.42 and 0.81 ㎍/㎖, respectively), while iristectorigenin A exhibited weak estrogenic activity (￡C50≥4 ㎍/㎖).

The present study was carried out to envisage the aerobic growth of Listeria monocytogenes and Yersinia enterocolitica on pork, which is one of the major meat sources in Korea. The results were compared with the previously developed predictive model systems for the verification of microbial growth in a real situation during pork processing. Pork loin samples (8.0 g, 5 mm thick) were aseptically prepared and inoculated with each pathogen by immersing into the respective inoculums for one min. Each of the samples were then wrapped with PE film and stored at 5, 10, and 15℃ up to 36 days to measure the growth profile of the respective pathogens. The growth parameters were calculated by using Gompertz equation and were compared with the previously reported data. The predicted generation time (GT) of L. monocytogenes at 5, 10 and 15℃ was 28.74, 7.85 and 4.02 hr, respectively, and for Y. enterocolitica was 10.29, 4.74 and 2.50 hr, at the same temperatures respectively. In this study, the GT values predicted on pork were slightly higher than the values predicted in other studies using liquid model systems. Unlike previous reports, both the pathogens were found to grow at 5℃ on pork. This finding recommends the necessity of controlling the growth of both the pathogens during the slaughtering process and distribution.

Growth inhibitory effects of ethanol extracts of green tea and pine needles on Bacillus stearothermophilus isolated from spoiled red bean paste were detected at concentrations higher than 750 ppm, and antimicrobial activity of pine needle extract was slightly higher than that of green tea exract. Growth inhibitory effect of pine needle extract in nutrient broth adjusted to pH 6.0, water-activity 0.92, and 45℃ Brix was observed at 500 ppm. These results indicated growth of B. stearothermophilus could be inhibited by adding pine needle and green tea extracts.

Enterococcus faecium MJ-14, having strong antilisterial activity, was isolated from Korean fermented food, Meju. MJ-14 showed the same phenotypic characteristics, but different sugar utilization, as reference strain, E. faecium KCCM12118. It could utilize D-xylose, amygdaline, and gluconate, whereas E. faecium KCCM12118 could not. Optimal condition for bacteriocin production by E. faecium MJ-14 was at 37℃ and pH 7.0. Bacteriocin activity appeared in mid exponential phase and increased rapidly up to stationary phase. Activity was significantly promoted in MRS broth containing 3.0% glucose, 1.5% lactose, 2.0% peptone, or 1.5% tryptone. Bacteriocins effectively inhibited Enterococcus faecalis and Listeria spp. of Gram-positive bacteria, and Helicobacter pylori of Gram-negative bacteria, but did not inhibit yeasts and molds. They were stable against heat (for 30 min at 100℃), pH (3.0-9.0), long-term storage (for 60 days at 4 or -20℃), and enzymatic digestion by catalase, proteinase K, papain, lysozyme, trypsin, chymotrypsin, and lipase, etc. Bacteriocin activity was completely inhibited by protease and pepsin, and 50% by a-amylase. Studies on PCR detection of enterocin structural genes revealed bacteriocins are identical to enterocins A and B.

Ethyl acetate-soluble neutral fraction of hot water extracts from the aerial parts of Angelica keiskei showed a 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity. Six antioxidative compounds were purified and isolated by various chromatographic procedures. Based on the analyses of FAB-MS and NMR, the isolated compounds were structurally elucidated as luteolin 7-O-B-D-glucopyranoside (1), quercetin 3-O-B-D-galactopyranoside (2), quercetin 3-O-B-D-glucopyranoside (3), quercetin 3-O-a-D-arabinopyranoside (4), kaempferol 3-O-a-D-arabinopyranoside (5), and luteolin 7-O-rutinoside (6). The glycosides of flavonols and luteolin showed DPPH radical-scavenging activity. One molecule of 2, 3, 4, 6, 1, and 5 scavenged 4.2, 4.2, 4.1, 2.5, 2.2, and 1.4 molecules of DPPH radical, respectively.

Commercial kimchi and sauerkraut were analyzed for their D- and L-lactic acid contents. Ranges of D- and L-lactic acid contents in commercial kimchi were 17-57 (38.51 mean) and 25-87 (64.47 mean) mM, respectively. Ratio of D-lactic acid on L-lactic acid (D/L) was 0.50-0.80 (0.60 mean). Ranges of D- and L-lactic acid contents in commercial sauerkraut were 68.96-103.62 (88.97 mean) and 74.46-82.26 (78.91 mean) mM, respectively, with D/L of 0.90-1.26 (1.13 mean). Results reveal kimchi and sauerkraut contained a significant amount of D-lactic acid, with sauerkraut showing a higher content than kimchi, while L-lactic acid contents were not significantly different.

Moisture sorption characteristics of edible composite films were determined and compared against moisture barrier properties. Edible composite films were Z1 (zein film with polyethylene glycol(PEG) and glycerol), Z2 (zein film with oleic acid), ZA1 (zein-coated high amylose corn starch film with PEG and glycerol), and ZA2 (zein-coated high amylose corn starch film with oleic acid). Z2 film showed the lowest equilibrium moisture content (EMC), monolayer value (W m), water vapor permeability (WVP), and water solubility (WS). Surface structure of Z2 was relatively denser and finer than that of other edible films. GAB W m and C values decreased, while K values increased with increasing temperature. Correlation coefficients of WS:EMC and WVP:EMC at Aw 0.75 were higher than those of WS: W m and WVP: W m, respectively. EMC values at Aw 0.75 appeared useful for evaluating or predicting moisture barrier properties of edible films.

The acaricidal activities of 12 commercial constituents derived from Eugenia caryophyllata leaf oils against Dermatophagoides farinae, D. pteronyssinus and Tyrophagus putrescentiae adults were examined using an impregnated fabric disk application and compared with that of the commercial benzyl benzoate as synthetic acaricide. On the basis of LD50 values, the most toxic compound was methyl eugenol (4.13 ㎍/㎠), followed by methyl isoeugenol (4.19 ㎍/㎠), isoeugenol (4.29 ㎍/㎠), eugenol (4.94 ㎍/㎠), and acetyl eugenol (13.91 ㎍/㎠) against D. farinae. In the case of D. pteronyssinus, isoeugenol (2.93 ㎍/㎠) was the most toxic, followed by methyl isoeugenol (3.28 ㎍/㎠), methyl eugenol (3.87 ㎍/㎠), eugenol (3.92 ㎍/㎠), and acetyl eugenol (7.21 ㎍/㎠). These results suggest that D. pteronyssinus may be controlled more effectively by the application of eugenol congeners than D. farinae. In comparison with synthetic acaricides, the acaricidal activities of eugenol, isoeugenol, methyl eugenol, and methyl isoeugenol were about 1.9-2.2 times more toxic than benzyl benzoate. Furthermore, the most toxic constituent against T. putrescentiae was exhibited on eugenol (10.11 ㎍/㎠), followed by methyl eugenol (38.67 ㎍/㎠) and acetyl eugenol (70.09 ㎍/㎠), but no activity was observed for isoeugenol and methyl isoeugenol. The results suggested that eugenol congeners may be useful as a new source for selective control of house dust mites and stored food mites.

Chinese cabbage and spinach applied with eight pesticides at two different rates were subjected to brining, heat-cooking, and blanching to determine residue or transfer ratios of those pesticides. Residue ratio in discarded inedible portion varied significantly, 0-94%, depending on pesticides applied, vegetable type, and cooking processes. Average reduction ratios of residues during cooking process were 78, 46, 23, 12, 10, 9, 8, and 2% in dichlorvos, diazinon, chlorpyrifos, endosulfan, EPN, cypermethrin, deltamethrin, and fenvalerate, respectively.

Ethnic Korean onggi earthenwares were fabricated using different clay formulations and glazing treatments. Their permeability properties against oxygen, carbon dioxide, and moisture were measured at 20℃ and examined from the aspect of food preservation. Onggi walls consisted of micropores that offered higher gas and moisture permeation rates when compared with other food packaging materials. Earthenware walls were unique in having CO2/O2 permeability ratios of 0.60-1.00. Gas and moisture permeabilities were lower, with wall structure having lower porosity and surface glazing. Results revealed onggi jar packages of grape fruits could attain wide range of O2 and CO2 concentrations. Onggi containers present good opportunity to obtain optimum packaging conditions for respiring or ripening products, depending on commodity type.

Squalene synthase (SQS) inhibitors were screened from various plants and food extracts. Effective SQS inhibitor was purified from fermented soybean paste using ethanol extraction, HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, and crystallization. Through UV spectrometry, 1H NMR, 13C NMR, and mass spectrometry, SQS inhibitor was identified as daidzein with molecular mass of 254 and molecular formula of C15H10O4. Daidzein showed IC50 value of 50 nmol/L against SQS, confirming its potential as therapeutic agent for hypercholesterolemia.

초 록 Bone resorption surrounding tooth root causes tooth loss in periodontitis patients. Osteoclast has bone resorption activity. Effects of Artemisia asiatica on bone resorption induced by periodontopathogens, Porphyromonas gingivalis and Treponema denticola, were examined using co-culture systems of mouse osteoblasts and bone marrow cells. Addition of A. asiatica ethanol extract to bacterial sonicate abolished bacteria-induced osteoclastogenesis. To determine inhibitory mechanism of A. asiatica against osteoclastogenesis, effects of A. asiatica on expressions of osteoclastogenesis-inducing factors such as receptor activator of NF-xB ligand (RANKL), prostaglandin K2 (PGK2), interleukin (IL)-1, and tumor necrosis factor (TNF)-a, in osteoblasts were examined. A. asiatica suppressed expressions of RANKL, PGK2, IL-1B, and TNF-a increased by each bacterial sonicate. These results suggest inhibitory action of A. asiatica against osteoclastogenesis is associated with down-regulations of RANKL,PGK2 IL-1B, and TNF-a expressions.

The effect of treatment with pine needle oil upon rat hepatocytes exposed to alcohol was investigated. The body weight gain, ratio of liver and kidney to body weight, and serum biochemistry of rats administered both alcohol and pine needle oil were compared to control rats treated with alcohol alone. Normal untreated control rats, negative control rats with ethanol treatment, positive control rats with both alcohol and the commercially available hangover cure solution (HCS) treatment and the test group with both alcohol and pine needle oil treatment exhibited aspartate aminotransferase (AST) levels of 84.43±47.88 U/L, 254.57±463.20 U/L, 70.29±12.60 U/L and 67.00±5.06 U/L, respectively, and cholesterol levels of 95.71±6.86 ㎎/㎗, 113.80±38.19 ㎎/㎗ nd, 95.71±6.30 ㎎/㎗ and 82.29±4.98 ㎎/㎗ respectively. Alanine aminotransferase (ALT) levels were 44.00±9.04 U/L in normal untreated control rats, increased to 215.43±428.93 U/L with the administration of ethanol, but interestingly were significantly reduced to 37.83±6.57 U/L in the test group (p<0.05). Triglyceride (TG) levels were 39.57±8.62 ㎎/㎗ in normal untreated rats, increased to 73.71±61.20 ㎎/㎗ in rats administered alcohol, but were reduced to 26.14±4.82 ㎎/㎗ in the test group (p<0.0l). The pine needle oil treatment significantly reduced the levels of AST, ALT and TG compared to the control rats. These results indicate that pine needle oil can positively mediate the effects of alcohol on hepatocytes and general liver functions.

In this study, the ameliorating effect of soybean embryos on the impact of alcohol consumption was investigated on rat hepatocytes and in reducing total serum cholesterol levels and total serum lipid levels. Liver histology and two clinically important enzyme markers, aspartate aminotransferase (AST) and alanine aminotransferase (ALT), of rats administered with both alcohol and soybean embryo were compared with a control group. The treatment regimen of soybean embryo significantly reduced the serum ALT and AST levels of the subjects, demonstrating the hepato-protective effects of soybean embryo. Electron microscopy indicated that the administration of soybean embryo preserved the important hepatocyte structures and prevented the presence of lipid droplets and secondary lysosomes. Furthermore, total cholesterol and total lipid levels were significantly reduced. These results indicate that treatment with soybean embryo can positively mediate the effects of alcohol on hepatocytes and general liver functions.

To improve water-resistance and physical properties of sodium alginate film, effects of sodium alginate and plasticizer concentrations, divalent cation types and concentrations, and immersion time of films into divalent cation solutions on sodium alginate films were evaluated, based on elongation strength (ES), elongation rate (E), water vapor permeability (WVP), and water solubility (WS). Film made from 1.5% sodium alginate solution (w/w) had low WVP and WS, which are optimal characteristics for application of film preparation. Addition of plasticizer increased E and WS. Less than 2% CaCl2 addition and 15min immersion time reduced WVP, WS, and E significantly (p<0.05). Sodium alginate films treated with CuCl2, and ZnCl2 solutions had lower WVP and WS, whereas MgCl2 had no influence on improving water resistance of films.

Composite films were prepared with soy protein isolate (SPI) and various clay minerals by casting from polymer and clay water suspension. Effects of clay minerals on film thickness, moisture content (MC), tensile strength (TS), elongation at break (E), water vapor permeability (WVP), and water solubility (WS) were tested. Properties including thickness, surface smoothness, and homogeneity of films prepared with organically modified montmorillonite (O-MMT), Wamok clay (W-clay), bentonite, talc powder, and zeolite were comparable to those of control SPI films. TS increased significantly (p<0.05) in films prepared with O-MMT and bentonite, while WVP decreased significantly (p<0.05) in bentonite-added films. WS of most nanocomposite films decreased significantly (p<0.05).

Polyphenoloxidase (PPO) was extracted from Solanum tuberosum Jasim by various chromatographic methods and was subsequently purified and characterized. PPO was purified upto 78-fold from the crude extract. SDS-PAGE profile of the enzyme showed a major subunit of PPO with molecular weight of 40 kDa. The optimum pH and temperature for the maximum activity of PPO was 6.5 and 25℃, respectively. The enzyme was found to be quite stable between 10 and 40℃, whereas it was almost inactivated at 70℃ when incubated for 30 min. Substrate specificity study indicated that catechol was the most suitable substrate for PPO isolated from purple-fleshed potato with a Km value of 21.1 mM. The most effective inhibitor was ascorbic acid, followed by L-cysteine, citric acid, EDTA, and boric acid. Studies on the effect of metal ion on PPO activity showed that magnesium and copper were inhibitory, while iron and zinc ions increased the activity of PPO.

Hydrogen-donating capacity, scavenging activity of reactive oxygen including superoxide anion radical and hydrogen peroxide, metal-chelating activity, and reducing power of garlic extracts were investigated. All tested garlic extracts exhibited in vitro antioxidant activities, with Uiseong extract showing highest hydrogen-donating and hydrogen peroxide-scavenging activities, and reducing power, followed by Seosan and Samchek extracts, in proportion to total thiosulfinate contents. Higher scavenging activity of superoxide anion radical was observed in Uiseong than Seosan and Samchek extracts. Metal-chelating activity increased in order of Uiseong < Seosan < Samchek, showing inverse relations to total thiosulfinate content. Garlic extracts of Uiseong and Seosan showed weak prooxidant activities and that of Samchek showed strong antioxidant activity against -induced human LDL oxidation. Protective effects on peroxyl and hydroxyl radical-induced DNA strand damages were observed in all tested garlic cloves. These results indicate growing conditions of garlic cloves affect total thiosulfinate content and antioxidant activities.

The selective extraction behavior of lactoferrin (Lf) from whey protein mixture was examined using reverse micelles formed by the cationic surfactant, cetyldimethylammonium bromide (CDAB). The major whey proteins, including -lactoglobulin, -lactalbumin and bovine serum albumin, were solubilized from aqueous phase to organic phase while Lf was recovered in the aqueous phase. The solubilization behaviors of the proteins were manipulated by the process parameters such as the pH and salt concentration of the aqueous phase and the surfactant concentration in the organic phase. Efficient forward extraction was achieved with sodium borate buffer (50 mM, pH 9) containing 50 mM KCl and organic phase containing 100 mM CDAB. Based on SDS-PAGE and densitometry, about 96% of the initial Lf remained in the aqueous phase after forward extraction. The dialyzed Lf fully maintained its bacteriostatic activity against E. coli O157:H7.

The genotoxicological safety of fermented vegetables pasteurized by gamma irradiation was examined to consider the possibility of the application of irradiation for extending of fermented vegetables. A fermented vegetable was irradiated at 20 kGy to assure its toxicological safety even at a high dose of radiation. The Ames test with Salmonella typhimurium (TA98, TA100, TA1535, TA1537) and Escherchia coli (WP2), and the chromosomal aberration test in Chinese hamster lung (CHL) cells were performed. In vivo micronucleus test were conducted in mouse bone marrow cells. With or without metabolic activation, negative results were obtained in the Ames test and the chromosomal aberration test. In the micronucleus test, there was no enhancement in the formation of micronucleus, and there were no such significant differences between the irradiated and non-irradiated samples. The observed results indicated that, a level of 20 kGy of gamma irradiation on the fermented vegetable did not bring about any genotoxic effects under the described experimental conditions.

Although many studies have been performed to elucidate the molecular consequences of ultraviolet irradiation, little is known about the effect of natural products. Ultraviolet irradiation is widely considered to be an environmental stress. Here we investigated the effect of 2',4',7-trihydroxyisoflavone on the regulation of MMP-1 and type 1 procollagen in Ultraviolet irradiation of cultured human dermal fibroblasts. Phytochemical investigation of the whole plants of Viola hondoensis led to the isolation of five flavonoids. The structures of these compounds were identified 2',4',5,7-tetrahydroxyisoflavone (1), 2',4',7-trihydroxyisoflavone (2), 4',7-dihydroxyflavone (3), isoorientin (4), and isovitexin (5) using spectroscopic analysis. Among these, 2',4',7-trihydroxyisoflavone reduced the expression of MMP-1 at the protein levels in a dose-dependent manner by ultraviolet irradiation. Taken together, our results suggest that 2',4',7-trihydroxyisoflavone an important role in the reduction of MMP-1 induction by ultraviolet irradiation.

Purified compound with intestinal immune system-modulating properties, GWE-2c, was isolated from methanol extract of Gelidium amansii by sequential procedures with silica gel column, LH-20 Sephadex gel column, and thin-layer chromatographies. In the presence of GWE-2c, strong immunoactivity in Peyers patch cell-mediated bone marrow cells was observed in vitro. In vivo intestinal immune-modulating activity was also enhanced by crude phenolic compound (GWE) of G. amansii in a dose-dependent manner. Investigation of production of several cytokines in Peyer's patch cells upon stimulation with GWE in vivo revealed the levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-6 increased. Results suggest that the phenolic compound from G. amansii represents immunopotentiator and biological response modifier at in vitro and in vivo levels.

Lipid peroxidation is a primary cause of quality deterioration in meat and meat products. Free radical chain reaction is the mechanism of lipid peroxidation and reactive oxygen species (ROS) such as hydroxyl radical and hydroperoxyl radical are the major initiators of the chain reaction. Lipid peroxyl radical and alkoxyl radical formed from the initial reactions are also capable of abstracting a hydrogen atom from lipid molecules to initiate the chain reaction and propagating the chain reaction. Much attention has been paid to the role of iron as a primary catalyst of lipid peroxidation. Especially, heme proteins such as myoglobin and hemoglobin and "free" iron have been regarded as major catalysts for initiation, and iron-oxygen complexes (ferryl and perferryl radical) are even considered as initiators of lipid peroxidation in meat and meat products. Yet, which iron type and how iron is involved in lipid peroxidation in meat are still debatable. This review is focused on the potential roles of ROS and iron as primary initiators and a major catalyst, respectively, on the development of lipid peroxidation in meat and meat products. Effects of various other factors such as meat species, muscle type, fat content, oxygen availability, cooking, storage temperature, the presence of salt that affect lipid peroxidation in meat and meat products are also discussed.