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51.
Polyhydroxylated alkaloids isolated from mulberry trees (Morusalba L.) and silkworms (Bombyx mori L.) 总被引:2,自引:0,他引:2
Asano N Yamashita T Yasuda K Ikeda K Kizu H Kameda Y Kato A Nash RJ Lee HS Ryu KS 《Journal of agricultural and food chemistry》2001,49(9):4208-4213
New polyhydroxylated alkaloids, (2R,3R,4R)-2-hydroxymethyl-3,4-dihydroxypyrrolidine-N-propionamide from the root bark of Morus alba L., and 4-O-alpha-D-galactopyranosyl-calystegine B(2) and 3 beta,6 beta-dihydroxynortropane from the fruits, were isolated by column chromatography using a variety of ion-exchange resins. Fifteen other polyhydroxylated alkaloids were also isolated. 1-Deoxynojirimycin, a potent alpha-glucosidase inhibitor, was concentrated 2.7-fold by silkworms feeding on mulberry leaves. Some alkaloids contained in mulberry leaves were potent inhibitors of mammalian digestive glycosidases but not inhibitors of silkworm midgut glycosidases, suggesting that the silkworm has enzymes specially adapted to enable it to feed on mulberry leaves. The possibility of preventing the onset of diabetes and obesity using natural dietary supplements containing 1-deoxynojirimycin and other alpha-glucosidase inhibitors in high concentration is of great potential interest. 相似文献
52.
Ichikawa M Ryu K Yoshida J Ide N Kodera Y Sasaoka T Rosen RT 《Journal of agricultural and food chemistry》2003,51(25):7313-7317
The extract of garlic skins (peels) showed strong antioxidant activity, and some responsible constituents were isolated and identified. Garlic (Allium sativum L.) has been used as an herbal medicine, but there is no report on the health benefits of the skin or peel. In this study, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of garlic skin extract was evaluated. Using chromatographic techniques, the active constituents were isolated and subsequently identified. Analyses by high-performance liquid chromatography coupled with a photodiode array detector (HPLC-PDA) suggested that these compounds were phenylpropanoids, which had a characteristic absorbance at 300-320 nm. Liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance analyses allowed the chemical structures of the isolated constituents to be postulated. The proposed compounds were subsequently synthesized and compared with the constituents in the extract using HPLC-PDA and LC-MS. N-trans-Coumaroyloctopamine, N-trans-feruloyloctopamine, guaiacylglycerol-beta-ferulic acid ether, and guaiacylglycerol-beta-caffeic acid ether were identified as were trans-coumaric acid and trans-ferulic acid. Also, the antioxidant activities of these compounds were determined. 相似文献
53.
Vo TS Ngo DH Kim JA Ryu B Kim SK 《Journal of agricultural and food chemistry》2011,59(22):12193-12197
A peptide possessing antihypertensive activity was purified from Nile tilapia ( Oreochromis niloticus ) gelatin using alcalase, Pronase E, pepsin, and trypsin. Among them, the alcalase hydrolysate exhibited the highest angiotensin converting enzyme (ACE) inhibitory activity. Therefore, it was further analyzed, and a potent ACE inhibitory peptide of DPALATEPDPMPF (1382 Da) was separated and purified. In addition, the protective effect of the purified peptide against free radical-induced cellular and DNA damage in murine microglial cells (BV-2) was determined. These results suggest that the peptide isolated from Nile tilapia (O. niloticus) gelatin acts as a candidate against hypertension and oxidative stress and could be used in health-functional foods. 相似文献
54.
Kim EJ Kwon J Park SH Park C Seo YB Shin HK Kim HK Lee KS Choi SY Ryu do H Hwang GS 《Journal of agricultural and food chemistry》2011,59(16):8806-8815
Angelica gigas obtained from different geographical regions was characterized using (1)H nuclear magnetic resonance (NMR) spectroscopy and ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) followed by multivariate data analyses. Principal component analysis (PCA) and orthogonal partial least-squares-discriminant analysis (OPLS-DA) score plots from (1)H NMR and UPLC-MS data sets showed a clear distinction among A. gigas from three different regions in Korea. The major metabolites that contributed to the discrimination factor were primary metabolites including acetate, choline, citrate, 1,3-dimethylurate, fumarate, glucose, histamine, lactose, malate, N-acetylglutamate, succinate, and valine and secondary metabolites including decursin, decursinol, nodakenin, marmesin, 7-hydroxy-6-(2R-hydroxy-3-methylbut-3-ethyl)coumarin in A. gigas roots. The results demonstrate that (1)H NMR and UPLC-MS-based metabolic profiling coupled with chemometric analysis can be used to discriminate the geographical origins of various herbal medicines and to identify primary and secondary metabolites responsible for discrimination. 相似文献
55.
Kyung Bo KO Gap‐Don Kim Dong‐Geun Kang Yeong‐Hwa Kim Ik‐Dong Yang Youn‐Chul Ryu 《Animal Science Journal》2015,86(4):428-434
The purpose of this study was to establish the effects of weaning age and weight on pigs, and their interaction with carcass traits and meat quality. A total of 468 piglets were obtained from 57 sows and four boars and grouped by age at weaning (D21, 18–24 days; D28, 25–32 days). Each weaning group was subdivided into three weight groups (L, M and H) according to weaning weight. The D28 group had heavier carcass weight, redness and yellowness, but had lower marbling scores and less drip loss than the D21 group (P < 0.05). The pigs with a light weight at weaning had higher carcass weights and lower yellowness than did pigs with a medium or heavy weight at weaning (P < 0.05). Weaning age was found to have a negative correlation with drip loss, while weaning weight was negatively correlated with carcass weight and drip loss (P < 0.05). We concluded that carcass and meat quality traits in pigs were significantly related to their age and weight at weaning. Therefore, we find that piglet weaning age and weight are no less important than post‐weaning growth performance and behavior, with regard to carcass traits and meat quality. 相似文献
56.
Seasonal variations of fatty acids in various Korean shellfish were investigated in relation to the changes in total fatty acids contents, the ratio of polyunsaturated fatty acids to saturated fatty acids (P/S), and that of n-3 fatty acids to n-6 fatty acids (n-3/n-6). A distinct seasonal pattern was found in total fatty acids contents with maximal values in early summer and minimal values in late summer. The percentage of monounsaturated fatty acids was lowest in most species throughout the year. In summer months, the proportion of polyunsaturated fatty acids decreased while that of saturated fatty acids increased. The major contributing factor to the seasonal variation of polyunsaturated fatty acids was n-3 fatty acids. These results led to the lowest levels of P/S and n-3/n-6 in summer. Nevertheless, the data suggest that bivalve shellfish would be excellent sources of n-3 fatty acids, especially eicosapentaenoic acid and docosahexaenoic acid. 相似文献
57.
Extrusion with CO2 injection was developed to simplify the process of producing vacuum‐puffed yukwa (rice snacks). The effects of feed moisture content and CO2 injection on the characteristics of extruded pellets (maximum viscosity and degree of gelatinization) and vacuum‐puffed yukwa (expansion ratio, bulk density, hardness, and color) were investigated. Higher feed moisture increased the size of vacuum‐puffed yukwa and the degree of gelatinization, whereas the maximum viscosity decreased. Maximum viscosity and gelatinization degree of extruded pellets were highly correlated with expansion ratio, bulk density, hardness, and color values of vacuum‐puffed yukwa. Increasing feed moisture content significantly increased expansion ratio but decreased bulk density and hardness. CO2 injection decreased bulk density and hardness of vacuum‐puffed yukwa. 相似文献
58.
Little is known of the association of enterohemorrhagic Escherichia coli O157:H7/NM (EHEC O157) with disease in naturally infected calves, although cattle have been known as a major source for EHEC O157 outbreaks in humans. In this study, we investigated the occurrence of EHEC O157 in calves associated with/without diarrhoea to examine if EHEC O157 is involved in calf diarrhoea and to characterize the isolates. Four hundred and ninety eight diarrhoeic and non-diarrhoeic young calves from 115 different farms were examined. Of 244 diarrhoeic calves, 24 (9.8%) were positive for EHEC O157, and of 254 non-diarrhoeic calves, 7 (2.8%) were positive. EHEC O157 was recovered from 12/76 (15.79%) of diarrhoeic calves less than 2-week-old, and no EHEC O157 was detected in this age group of non-diarrhoeic calves. This implicates EHEC O157 as a possible cause of the disease in naturally infected neonatal calves. The occurrence of EHEC O157 was relatively lower in the older calves (aged older than 8 weeks) and no significant difference was found in the occurrence rates between these diarrhoeic and non-diarrhoeic calves. PCR analysis of virulence markers revealed that the isolates carried various virulence genes such as Ehly, eae, stx1 and stx2, which underlines the potential importance of these attributes for the infection, colonization and possible pathogenesis of calf diarrhoea. 相似文献
59.
Global warming causes the exacerbation of rice growing environment, which seriously affects rice growth and reproduction, and finally results in the decrease of rice yield and quality. We investigated the activities of aspartate metabolism enzymes in grains, and the contents of Aspartate-family amino acids and protein components to further understand the effects of high temperature (HT) on rice nutritional quality during rice grain filling. Under HT, the average activities of aspartate aminotransferase (AAT) and aspartokinase (AK) in grains significantly increased, the amino acid contents of aspartate (Asp), lysine (Lys), threonine (Thr), methionine (Met) and isoleucine (Ile) and the protein contents of albumin, globulin, prolamin and glutelin also significantly increased. The results indicated that HT enhanced Asp metabolism during rice grain filling and the enhancement of Asp metabolism might play an important role in the increase of Asp-family amino acids and protein components in grains. In case of the partial appraisal of the change of Asp-family amino acids and protein components under HT, we introduced eight indicators (amino acid or protein content, ratio of amino acid or protein, amino acid or protein content per grain and amino acid or protein content per panicle) to estimate the effects of HT. It is suggested that HT during rice grain filling was benefit for the accumulation of Asp-family amino acids and protein components. Combined with the improvement of Asp-family amino acid ratio in grains under HT, it is suggested that HT during grain filling may improve the rice nutritional quality. However, the yields of parts of Asp-family amino acids and protein components were decreased under HT during rice grain filling. 相似文献
60.
Kana Tozaki Junpei Kimura Masahiro Yasuda Nobuyuki Ryu Testuo Nasu Anton Pernthaner Wayne R. Hein 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):1-6
The follicle-associated epithelium (FAE) of Peyer''s patches (PPs) contains M cells that are important for reducing mucosal immune responses by transporting antigens into the underlying lymphoid tissue. We generated a monoclonal antibody (C6) that reacted with the FAE of calf ileal PPs, and analyzed the characteristics of C6 using immunohistochemistry and Western blotting. FAE of the ileal PP was stained with C6 during both late fetal developmental and postnatal stages. Neither the villous epithelial cell nor intestinal crypt basal cells were stained at any developmental stage. During the prenatal stages, FAE of the jejunal PP was C6-negative. However, a few C6-positive cells were distributed diffusely in some FAE of the jejunal PPs during the postnatal stages. The protein molecular weight of the antigen recognized by C6 was approximately 45 kDa. These data show that C6 is useful for identifying the FAE in ileal PPs and further suggest that differentiation of the FAE in these areas is independent of external antigens. 相似文献