Effects of temperature and agitation rate on the formation of conjugated linoleic acids in soybean oil during hydrogenation process.     

M O Jung  S H Yoon  M Y Jung 《Journal of agricultural and food chemistry》2001,49(6):3010-3016

The effects of hydrogen temperature and agitation rate on the formation of total conjugated linoleic acids (CLA) and CLA isomers were studied during hydrogenation with a selective Ni catalyst. The CLA isomers were identified by using a 100-m cyano-capillary column gas chromatograph and a silver ion-impregnated HPLC. Reaction temperature and agitation rate greatly affected the quantities of total CLA and individual CLA isomers, and the time to reach the maximum quantity of CLA in the partially hydrogenated soybean oil. As the hydrogenation temperature increased, the maximum quantity of CLA in soybean oil increased, but the time to reach the maximum CLA content decreased. By increasing the hydrogenation temperature from 170 to 210 degrees C, the quantity of CLA obtained was about 2.6 times higher. As the agitation rate decreased, the CLA formation in soybean oil increased, and the time to reach the maximum CLA content also increased. The maximum CLA contents in soybean oil obtained during hydrogenation at 210 degrees C with agitation rates of 300, 500, and 700 rpm were 162.82, 108.62, and 66.15 mg total CLA/g oil, respectively. The present data showed that it is possible to produce high-CLA-content soybean oil without major modification of fatty acid composition by short-time (10 min) selective hydrogenation under high temperature and low agitation rate conditions.  相似文献   

Fermentation of a bacterial cellulose/xylan composite by mixed ruminal microflora: implications for the role of polysaccharide matrix interactions in plant cell wall biodegradability     

Weimer PJ  Hackney JM  Jung HJ  Hatfield RD 《Journal of agricultural and food chemistry》2000,48(5):1727-1733

Growth of the cellulose-synthesizing bacterium Acetobacter xylinum ATCC 53524 in media supplemented with 5% (w/v) glucose and 0.2% (w/v) of a water-soluble, nearly linear xylan from tobacco stalks resulted in the synthesis of a highly crystalline composite having a xylose/glucose ratio ranging from 0.06 to 0.24. The digestion of one composite (88% cellulose/12% xylan) by mixed ruminal microflora displayed kinetics of gas production similar to those of an unassociated mixture of the two components added in a xylan/cellulose ratio similar to that of the composite. The data suggest that intimate association of xylan and cellulose, as is typically found in secondary plant cell walls, does not inhibit the rate of digestion of the component polysaccharides.  相似文献   

Fresh Israeli Jaffa blond (Shamouti) orange and Israeli Jaffa red Star Ruby (Sunrise) grapefruit juices affect plasma lipid metabolism and antioxidant capacity in rats fed added cholesterol   总被引：2，自引：0，他引：2  

Gorinstein S  Leontowicz H  Leontowicz M  Krzeminski R  Gralak M  Martin-Belloso O  Delgado-Licon E  Haruenkit R  Katrich E  Park YS  Jung ST  Trakhtenberg S 《Journal of agricultural and food chemistry》2004,52(15):4853-4859

The bioactivity of Israeli Jaffa blond (Shamouti) fresh orange and Israeli Jaffa red Star Ruby (Sunrise) grapefruit juices was investigated in vitro and in vivo. The contents of bioactive compounds of these juices were determined. The influence of bioactive compounds on plasma lipids and plasma antioxidant activity in rats fed cholesterol-containing and cholesterol-free diets was assessed. Significant differences in the contents of dietary fibers were not found. The contents of total polyphenols, flavonoids, and anthocyanins in fresh orange and grapefruit juices were 962.1 +/- 27.2 and 906.9 +/- 27.1; 50.1 +/- 3.3 and 44.8 +/- 3.2; and 69.9 +/- 5.6 and 68.7 +/- 5.5 microg/mL, respectively. The antioxidant potential measured by the scavenging activity against nitric oxide, the beta-carotene-linoleate model system (beta-carotene), and the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethyl-benzothiazoline-6-sulfonic acid) diamonium salt assays was higher in orange juice but not significantly. A high level of correlation between contents of total polyphenols and flavonoids and antioxidant potential values of both juices was found. Diets supplemented with orange and to a lesser degree with grapefruit juices improved plasma lipid metabolism only in rats fed added cholesterol. However, an increase in the plasma antioxidant activity was observed in both groups. In conclusion, fresh orange and grapefruit juices contain high quantities of bioactive compounds, which guarantee their high antioxidant potential, and the positive influence on plasma lipid metabolism and plasma antioxidant activity could make fresh orange and grapefruit juices a valuable supplement for disease-preventing diets.  相似文献   

Modulations of the Bcl-2/Bax family were involved in the chemopreventive effects of licorice root (Glycyrrhiza uralensis Fisch) in MCF-7 human breast cancer cell   总被引：10，自引：0，他引：10  

Jo EH  Hong HD  Ahn NC  Jung JW  Yang SR  Park JS  Kim SH  Lee YS  Kang KS 《Journal of agricultural and food chemistry》2004,52(6):1715-1719

Recently, cancer chemoprevention with strategies using foods and medicinal herbs has been regarded as one of the most visible fields for cancer control. Genistein in soy, American ginseng, and resveratrol are well-known to have antiproliferative properties in human breast cancer. Licorice root is a botanical, a shrub native to southern Europe and Asia, which primarily has desirable qualities in sweetening and herbal medicine. In this study, licorice (Glycyrrhiza uralensis Fisch) root also inhibits cell proliferation in human breast cancer cell. The cell proliferation study demonstrated that licorice root reduced the proliferation of MCF-7 cells in a dose- and time-dependent manner. The extracts were fractionated in CHCl(3), EtOAc, C(6)H(14), and CH(3)OH-H(2)O (70:30), and these extracts of licorice root (50 microg/mL) induced DNA fragmentation demonstrated by Hoechst 33258 staining. Apoptosis also determined the sub-G1 accumulation by flow cytometry analysis. These results were consistent with specific cleavage of PARP and antiapoptotic protein Bcl-2 and up-regulation of proapoptotic protein Bax demonstrated by Western blotting. Our findings suggest that licorice root may have chemopreventive effects against human breast cancer through the modulation of the expression of the Bcl-2/Bax family of apoptotic regulatory factors.  相似文献   

Methylation methods for the quantitative analysis of conjugated linoleic acid (CLA) isomers in various lipid samples   总被引：8，自引：0，他引：8  

Park SJ  Park CW  Kim SJ  Kim JK  Kim YR  Park KA  Kim JO  Ha YL 《Journal of agricultural and food chemistry》2002,50(5):989-996

Precise methylation methods for various chemical forms of conjugated linoleic acid (CLA), which minimize the formation of t,t isomers and allylmethoxy derivatives (AMD) with the completion of methylation, were developed using a 50 mg lipid sample, 3 mL of 1.0 N H(2)SO(4)/methanol, and/or 3 mL of 20% tetramethylguanidine (TMG)/methanol solution(s). Free CLA (FCLA) was methylated with 1.0 N H(2)SO(4)/methanol (55 degrees C, 5 min). CLA esterified in safflower oil (CLA-SO) was methylated with 20% TMG/methanol (100 degrees C, 5 min), whereas CLA esterified in phospholipid (CLA-PL) was methylated with 20% TMG/methanol (100 degrees C, 10 min), followed by an additional reaction with 1.0 N H(2)SO(4)/methanol (55 degrees C, 5 min). Similarly, CLA esterified in egg yolk lipid (CLA-EYL) was methylated by base hydrolysis, followed by reaction with 1.0 N H(2)SO(4)/methanol (55 degrees C, 5 min). These results suggest that for the quantitative analysis of CLA in lipid samples by GC, proper methylation methods should be chosen on the basis of the chemical forms of CLA in samples.  相似文献   

Structure of a new echinocystic acid bisdesmoside isolated from Codonopsis lanceolata roots and the cytotoxic activity of prosapogenins     

Lee KT  Choi J  Jung WT  Nam JH  Jung HJ  Park HJ 《Journal of agricultural and food chemistry》2002,50(15):4190-4193

We isolated a new saponin named codonoposide (1) from the roots of Codonopsis lanceolata (Campanulaceae) and characterized it as 3-O-[beta-D-xylopyranosyl(1-3)-beta-D-glucuronopyranosyl]-3beta,16alpha-dihydroxyolean-28-oic acid 28-O-[beta-D-xylopyranosyl (1-3)-alpha-L-rhamnopyranosyl (1-2)-alpha-L-arabinopyranosyl] ester by chemical, physicochemical, and 2DNMR techniques. Complete hydrolysis of 1 produced a sapogenin (1a), and the partial hydrolysis and further isolation afforded two prosapogenins (1b, 1c). The structures of 1a, 1b, and 1c were found to be 3beta,16alpha-dihydroxyolean-28-oic acid (echinocystic acid, 1a), 3-O-beta-D-glucuronopyranoside of 1a, and 3-O-beta-D-xylopyranosyl (1-3)-beta-D-glucuronopyranoside of 1a, respectively, on the basis of spectroscopic data. On MTT assay, 1a showed marginal cytotoxic activity whereas 1b exhibited more cytotoxicity than 1a. However, the bisdesmosylsaponin 1 exhibited no cytotoxicity (IC(50)>0.3 mM against tested cell lines). This result indicated that glycoside linkage of glucuronic acid at C-3 enhances the cytotoxicity of sapogenin (1a), and additive glycosylation of xylose to 1b strongly enhances the cytotoxicity of 3-O-monosaccharides (1b). Therefore, true forms of codonoposide for the cytotoxicity must be sapogenins or prosapogenins.  相似文献   

Influence of Oil Seed Rape and Faba Bean as Green Manure on Nitrogen Utilization in a Spring Cereal Rotation     

J. Jung    J. Dressel  R. Kuchenbuch 《Journal of Agronomy and Crop Science》1990,165(4):253-256

A lysimeter study was conducted to investigate how nitrogen uptake of spring wheat and oats and N leaching losses are differing when either oilseed rape or faba bean are grown as green manure. The experiment was conducted during 1982–1988, and fertilizer applied to the cereals was either farmyard manure, FYM, (6 and 12 g N/m²/year) or mineral fertilizer, MiF, at a rate of 6 g N/m². On average of the 7 year period faba bean increased N uptake of the cereals fertilized with FYM at harvest by 3–4 g/m². Differences between the two application rates were negligible. N-leaching losses increased twofold when faba bean was grown instead of oilseed rape. Growing faba bean after cereals supplied with MiF, too, increased N uptake of the cereals and significantly increased leaching losses.  相似文献   

Effects of dietary fiber of young adult genetically lean, obese and contemporary pigs: rate of passage, digestibility and microbiological data     

V H Varel  H G Jung  W G Pond 《Journal of animal science》1988,66(3):707-712

Twenty-one genetically lean, obese or contemporary slaughter weight castrated male pigs (6 mo old; seven of each genotype) were assigned to individual tether stalls and fed either a control diet (low fiber) or a diet containing 80% alfalfa meal (high fiber) at 1.50% of initial body weight for 71 d (1.75% for d 1 to 4). Apparent dry matter digestibility of the diets was estimated by determining acid insoluble ash in fecal samples. Fecal cellulolytic bacteria and total viable bacteria were enumerated at d 0, 14, 35, 49 and 70. Fecal inocula were used to determine 48-h in vitro digestibility of alfalfa meal fractions on the same days. Digesta rate of passage was determined by feeding a pulse dose of chromium-mordanted alfalfa fiber to the pigs fed the high-fiber diet. In vivo digestibility of both diets was less for the obese pigs than for the lean or contemporary genotypes. In vitro digestibility of alfalfa fiber fractions was not different between the genotypes fed either diet. When the high-fiber diet was fed, in vitro digestibility increased for all genotypes from d 0 to d 14, but not thereafter. The numbers of cellulolytic bacteria for all three genotypes were greater when pigs were fed the high-fiber diet (23.0 X 10(8), 51.6 X 10(8), 37.2 X 10(8) per gram fecal dry weight; obese, lean and contemporary, respectively) compared to the low-fiber diet (3.0 X 10(8), 3.2 X 10(8), 3.4 X 10(8), respectively).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Effect of dietary fiber on young adult genetically lean, obese and contemporary pigs: body weight, carcass measurements, organ weights and digesta content     

W G Pond  H G Jung  V H Varel 《Journal of animal science》1988,66(3):699-706

Twenty-one genetically lean, obese or contemporary barrows (6 mo old; seven of each genotype) were assigned to individual tether stalls and fed a control diet (low-fiber) or a diet containing 80% alfalfa meal (high-fiber) at 1.50% of initial body weight for 71 d (1.75% for d 1 to 4). Backfat thickness was recorded ultrasonically at 2-wk intervals, and body weight was recorded at the beginning and end of the 10-wk experiment. Pigs were slaughtered after a 24-h fast, and carcass weight, length and backfat thickness and cross-sectional area of the longissimus muscle were measured. Weights of cecum, heart, liver and kidney and of full and empty stomach and colon and empty small intestine were recorded. Volume and weight of colon and cecum contents were determined. Restriction of digestible energy reduced weight gain to zero or below in pigs fed alfalfa meal compared with 220 g daily in pigs fed the low-fiber diet. Restriction of energy reduced backfat in all three genotypes. Liver, kidney and empty segments of the gastrointestinal tract as a percentage of body weight were increased by high fiber. Obese pigs had smaller longissimus muscle area, more backfat and smaller liver, heart, empty stomach and colon than lean or contemporary pigs, but there were no diet X genotype interactions for any of these traits. Obese pigs consistently had smaller digesta volumes and dry matter weights than the other genotypes. The increased relative organ weights and the associated disproportionate contribution of these organs to body energy expenditure have important implications for effects on basal metabolic rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Effect of hay substitution on intake and digestibility of forage rape (brassica napus) fed to lambs     

M G Lambert  S M Abrams  H W Harpster  G A Jung 《Journal of animal science》1987,65(6):1639-1646

Intake and digestibility trials were conducted with sheep to evaluate the effect of adding various levels of a typical fibrous grass forage (neutral detergent fiber, NDF = 68%) to a high quality, low fiber (NDF = 22%) brassica forage. Four forage rape:orchardgrass hay diets (0, 40, 70, 100% rape content on a dry matter basis) were fed to groups of six Polled-Dorset crossbred growing wether lambs (39.6 kg) individually housed in metabolism crates. After a 7-d ad libitum intake period, a 7-d digestibility trial was conducted at 90% of the observed ad libitum intake level. Digestible dry matter intake (DDMI) per unit metabolic body weight increased as rape in the diet was increased from 0 to 70%, with increases in both dry matter intake and dry matter digestibility (DMD). However, DDMI was similar for lambs fed the 70 and 100% rape diets, with DMI decreasing to the same relative extent as DMD increased. Digestibility of the cell wall fraction of the two intermediate diets (40% rape and 70% rape) was lower than predicted from component forage digestibilities. This observation suggests the existence of an associative effect similar to that often reported when forage and concentrates are fed in various ratios. Forage brassicas appear to be utilized in the ruminant in a manner more typically resembling a concentrate than a forage.  相似文献