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1.
Intake of saturated and trans-fatty acids is a strong risk factor for coronary heart disease. We investigated the inhibitory effects of 2 hexane extracts from white (WBE) and black soybeans (BBE) on cellular fatty acid uptake in vitro. Transcellular uptake of elaidic acid (t18:1), a major trans-fatty acid present in processed foods, in Caco-2 monolayers was significantly reduced by 28.3 and 16.7% 60 min after WBE and BBE treatment, respectively. Results of flow cytometry (FACS) analysis showed significant reductions in boron-dipyrromethene (BODIPY) fluorescence-labeled fatty acid uptake by 35.4 and 40.2% with WBE and BBE treatment, respectively. BBE treatment significantly reduced the expression of fatty acid transport protein-4 and CD36 in Caco-2 cells, as determined by quantitative real time-polymerase chain reaction (qRT-PCR). Similar trends were found in WBE treatment, although to a lesser degree. These observations suggest that soybean extract may reduce fatty acid uptake and cellular fat accumulation by altering fatty acid transporter expression.  相似文献   

2.
Esterases are enzymes that present good potential in industrial application, and soybean seed can represent an alternative source for this enzyme. The extraction and esterase activity of Brazilian soybean seeds (Glycine max L.) were evaluated. Esterase activity was found in both the germinated and non-germinated seeds at 2.90 and 1.70 U/mg, respectively, with a concentration in the powdered extract (freeze dried) of 100 mg/mL. The enzyme showed a preference for the hydrolysis of short chain fatty acids (120.02 U/mL) and optimum pH for activity was pH 8.0 with optimum temperatures of 40 and 80°C. The enzyme showed stability at 70°C showing 60% of residual activity and activity increased with the addition of the following salts: NaNO3, K2SO4, and Na2SO4 in the reaction medium.  相似文献   

3.
Adsorption isotherm was obtained to assess the hygroscopicity of yew wood using the Hailwood-Horrobin sorption theory. Yew wood showed very low EMC values in the whole range of relative humidities. An interesting point was that the adsorption isotherms of the yew wood were almost identical to that of pine wood modified with 15.8% acetic anhydride.  相似文献   

4.
Sunflower protein extraction using sodium chloride solutions allows high extraction yields at pH ~6 while preventing oxidation and covalent binding of phenolic compounds to the proteins, which usually occurs under alkaline conditions. Since protein solubility is enhanced at high NaCl concentrations, isoelectric precipitation had to be adapted in the present study besides developing subsequent desalting steps. Precipitation losses decreased from 62 to 31% with increasing NaCl (0.6–2.0 mol/L) and protein concentrations of the solution (6–14 mg/mL) and decreasing pH of precipitation (pH 4.5–3.0). Maximum yields were achieved at low temperature (8 °C) and upon instant acid addition. After adsorptive removal of co-extracted phenolics from the protein extracts, overall protein yields were considerably higher after precipitation at pH 3.5 compared with 4.5, but only slightly higher after washing of the precipitates. The physico-chemical properties of the protein isolates did not differ significantly except for the marked protein denaturation upon precipitation at pH 3.5. From the proposed process, light-coloured protein isolates of high purity (>98%) are obtained, which are suitable for food use.  相似文献   

5.
The volatile composition of the essential oil from fresh gamguk (Chrysanthemum indicum) flowers was investigated. The volatile constituents were extracted by the hydro distillation method. Volatile compositional changes of gamguk prepared via different drying methods (shade- and freeze-drying methods) were also determined. Total 36, 63, and 55 volatiles constituents were confirmed in the essential oil from fresh and shade-, and freeze-dried flowers. Ketones were predominant in the volatiles of gamguk flowers (%): fresh, 43.8; shade dried, 30.3; and freeze dried, 36.1. Camphor was the most abundant volatile component in all samples, and the content of borneol was also remarkable. The content of camphor was higher in fresh sample than those of dried samples while borneol concentration was significantly increased in the dried samples.  相似文献   

6.
S-Alk(en)yl alka/enethiosulfinates formed in crushed garlic were purified by using recycling preparative HPLC. Allyl 2-propenethiosulfinate and methyl methanethiosulfinate were effective separated because no other thiosulfinates were coeluted with them. Allyl methanethiosulfinate and methyl 2-propenethiosulfinate, trans-1-propenyl methanethiosulfinate and methyl trans-1-propenethiosulfinate, (cis)- and (trans)-1-propenyl 2-propenethiosulfinate were eluted as 1 peak, respectively, and further separated by using additional kinds of column. Since the quantity of trans-1-propenyl trans-1-propenethiosulfinate (PPTHS) was small in garlic, PPTHS was isolated from a mixture of blanched onion homogenate and garlic alliinase and purified. Purified thiosulfinates can be employed for the study of antimicrobial activity, flavor, and greening of garlic.  相似文献   

7.
Pomegranate is getting an increasing attention for its health-promoting effects. Collection and characterization of plants of local sources has been performed, and five accessions have been propagated and cultivated in a collection field for extra situ investigations. Accessions differ for pomological traits and chemical composition. Three of them, MG1, MG2, and MG3, belong to typology with low-medium acidity and high sugar content, while the other two, Tordimonte A and B, belong to typology with high acidity. In the juice and in the peels’ extract of Tordimonte A accession a high level of punicalin has been found through chromatographic determinations, while the presence of punicalagin was found in the juice of accession MG1. The accessions MG1, MG2, and MG3 seem particularly suitable for direct commercialization of fruits due to the fruit traits and quality (sweet varieties), while Tordimonte A and B could be valuable for juice processing (sour varieties).  相似文献   

8.
The identification and characterization of Bacillus mojavensis KJS-3 was performed by in vitro tests. A 16S rDNA sequence and phylogenetic tree demonstrated that this isolate belongs to the B. mojavensis group. B. mojavensis KJS-3 supplies nutrients by synthesizing several vitamins. B. mojavensis KJS-3 produces α-amylase and protease. B. mojavensis KJS-3 is cultured well under aerobic conditions without gas production. B. mojavensis KJS-3 allows for assimilation of cholesterol and bile salt hydrolase activity. Finally, adhesion experiments using Caco-2 cells revealed that the adherence of B. mojavensis KJS-3 to Caco-2 cells was approximately 51.2±8.14%.  相似文献   

9.
This study aimed to evaluate the oils of soybean (S), papaya (Pa) and melon (Me) seeds and compounds oils SPa (80:20 w/w); SMe (80:20 w/w); and SPaMe (60:20:20 w/w/w) subjected to thermoxidation. Compound oils showed lower percentages of free fatty acids in relation to others, after 20 h. With the heating process, there was an increase in the quantity of saturated and monounsaturated acids. The quantity of carotenoids decreased, except in papaya seed oil that presented significant amount of carotenoids in 20 h. In relation the tocopherols, highlighted the presence of γ-tocopherol, except in the papaya oil. In 20 h, SMe and SPa still showed high amounts of tocopherols, with 76 and 85% of retention, respectively. With the thermoxidation, the amounts of phytosterols decreased. A great potential can be verified for the use of papaya and melon seed oils, in order to increase the oxidative stability of the soybean oil.  相似文献   

10.
This study investigated the transition between the free and bound forms of functional compounds in germinated black soybean. Black soybean was germinated at 25°C over 6 days and then the free and bound forms of functional compounds were extracted. Total free polyphenol, flavonoid, and phenolic acid contents in raw black soybean increased from 1.03 mg GAE/g, 0.29 mg CE/g, and 315.67 μg/g to 1.44mg GAE/g, 0.64mg CE/g, and 511.01 μg/g, respectively, by 4 days after germination. Changes to phenolic acid compositions can be divided into four groups, and the germination process can convert compounds to phenolic acid via anabolism and catabolism. The highest total free isoflavone content in germinated black soybean (3,724.40 μg/g) was observed at 4 days. Bound polyphenol, flavonoid, phenolic acid, and isoflavone contents decreased as the germination period increased. These results suggest that the germination process increased compound functionality in black soybean.  相似文献   

11.
Zinc (Zn), iron (Fe), magnesium (Mg), and calcium (Ca) in chickpea seed are important constituents in vegetarian diets. The aim was to investigate associations of these nutrients in different chickpea (Cicer arietinum L.) cultivars with phytic acid (PA), another naturally occurring constituent of grain that may influence the bioavailability of mineral micronutrients. Chickpea was grown at Saskatoon and Swift Current, SK, in 2002 and 2003, representing dryland production from high-yielding locations in western Canada. Minerals were measured by atomic absorption spectroscopy; PA was measured using high-performance anion-exchange conductivity detection methodology. Seed from 10 genotypes contained from 29 to 52 mg/kg Zn, 77–112 mg/kg Fe, 1,448–2,457 mg/kg Mg, 1,211–2,457 mg/kg Ca, to 3.8–9.0 mg/g PA. Phytic acid, Fe, Mg, and Ca decreased in 2003 from 2002 concentrations. Kabulis had greater Zn, the same Fe, but lower Mg and Ca concentrations than desi genotypes. Large-seeded genotypes had greater or the same Zn, the same Fe and Mg, but lower Ca than small-seeded genotypes. Iron and Ca concentrations positively correlated with PA concentration. Nutrients were affected by environment and genotype, which means that chickpea can be exploited by breeding, in addition to sourcing favorable nutritional profiles by environment, seed size, and market class.  相似文献   

12.
Fractionated high pressure extractions from dry and in natura elderberry pomace were performed in order to obtain anthocyanin rich extracts. Experiments were carried out using CO2 supercritical fluid extraction followed by enhanced solvent extraction (ESE) with CO2/EtOH–H2O mixtures (1–100%, v/v), to obtain anthocyanin rich fractions in the second step, at 313 K and ~20 MPa. Higher extract yields, anthocyanin contents and antioxidant activities occurred by the presence of water, both in the raw material and in the solvent mixture. The CO2 dissolved in the ESE solvent mixture favored either anthocyanin contents or antioxidant activities, which were not directly related. Comparing to the literature data for elderberries and grapes, these fractions had higher anthocyanins contents. From these results, an added economical value to this agroindustrial residue is proposed, using solvents and techniques “generally regarded as safe” in the food and pharmaceutical industries.  相似文献   

13.
Lactic acid bacteria (LAB) include species very closely related both physiologically and genotypically. Therefore, the identification of this bacteria group using conventional phenotypic methods is ambiguous and cumbersome. In this study, we have analyzed a recA gene fragment from 30 bacteria, including LAB and species common in the human gastrointestinal tract, aiming to evaluate the gene conservation among them and the development of primers and PCR conditions able to discriminate Lactobacillus plantarum strains from LAB closely related. The fragment with 995 bp of recA gene has grouped LAB, enterobacteria and bifidobacteria, in different clusters. A novel primer pair, LPrecAF and LPrecAR with 23 and 18 bp, respectively, has allowed the single amplification of a 108 bp fragment of L. plantarum strains contained in culture broth and fermented dairy samples. The observed detection limit for food samples and for cultures broth were 1 × 103 and 7 × 102 CFU mL−1, respectively. This approach proved to be a simple and efficient method for the identification and monitoring of L. plantarum in food, feeds, and culture broth. Moreover, the assay could be used in the studies from human or environmental microbiota.  相似文献   

14.
The homogenization of international wine market led to a gradual impoverishment of the genetic pool. In fact, in several Spanish Quality Demarcations, the most frequent international varieties are replacing the local ones. As a result, minor varieties, perfectly adapted to the local environmental conditions, are nowadays at risk of extinction. The study of minor varieties could provide useful inputs to satisfy the demand for new and interesting wine products. This work aims at filling a gap in the existing literature, focusing on the aromatic potential of minor varieties. Here, the study of glycosidic volatile compounds and the evaluation of the influence of several variables on aroma composition were considered. Fifty-one glycosidic compounds were identified and quantified. The results revealed differences for glycosidic compounds according to cultivars, berry color, clone and sample origin. The inclusion or not of the cultivars in Quality Demarcation was also discussed. Moreover, the synthesis of some compounds involved in these differentiations seems to have a genetic component. The characterization of aromatic potential of several minor varieties, achieved for the first time, revealed that some of these (Argamusa, Quigat, Pampolat girat, Excursach, Gorgollasssa or Mandón) could represent an excellent option for winemaking and commercial offer diversification strategies, besides being important for these cultivars conservation.  相似文献   

15.
Response surface methodology was applied to maximize the yield and productivity of carotenoids by Rhodotorula glutinis strain 1151 using supplemented tomato waste based medium. Higher concentration of tomato waste extract and yeast extract favored the production of carotenoids. In contrast to carotenogenesis higher concentration of yeast extract negatively affected the formation of biomass whereas higher amount of glucose in the medium favored biomass indicating that carotenogenesis is not correlated to biomass. The optimal concentration of medium components for maximum total carotenoids and corresponding biomass production as obtained from model were calculated to be as 660 mL/L, 1.5, 4.5, 7.4, and 10 g/L for tomato extract, malt extract, yeast extract, peptone, and glucose, respectively.  相似文献   

16.
A study was carried out on the disinfection efficiency of electrolyzed oxidizing water (EOW) on spores of Bacillus subtilis var. niger. The results showed a remarkable fungicidal rate of 100% after 20 min duration of 191 mg/L active available chlorine (ACC). The disinfection effect was improved with increased ACC or prolonged disinfection time, while organic interferents exerted a strong concentration-dependent inhibition against the disinfection. The disinfection mechanism was also investigated at bio-molecular level. EOW decreased dehydrogenase activity, intensified membrane permeability, elevated suspension conductivity, and caused leakage of intracellular K+, proteins, and DNA, indicating a damage of cell walls and membranes. Effects of EOW on microbiological ultra-structures were also verified by transmission electronic microscopy (TEM) images, showing that EOW destroyed protective barriers of the microbe and imposed some damages upon the nucleus area.  相似文献   

17.
The objective of this work was to evaluate the effect of six pretreatments on quality and nutritional contents of sliced Galega kale submitted to convective drying. Among all treatments, steam blanching was the most favourable, allowing improvements in retention of vitamin C, total antioxidant capacity and chlorophylls in comparison to the absence of pretreatment. Total phenolic losses were not reduced by steam blanching, but the retention was improved by combining this approach with a previous immersion in a metabisulphite solution. Moreover, steam blanching improved the colour parameters and appearance, providing a final dried product more similar to the fresh sample.  相似文献   

18.
The seasonal climate changes and their effects on flavanol and purine alkaloid contents of two leaves and a bud of tea were evaluated among 3 cultivars grown in Hangzhou, China. The results showed (−)-epigallocatechin (EGC), (−)-epicatechin (EC), (−)-epicatechin gallate (ECG) and (−)-epigallocatechin gallate (EGCG) increased, but (+)-catechin (C) decreased with increasing daily average temperature (DAT). Long period of precipitation (PRE) led to the declines of EGC, EC, ECG, EGCG and their total content (TC) but increased C content. Furthermore, relative humidity (RH) significantly affected EGC, TC and caffeine. Therefore, DAT, PRE and RH should not be ignored in tea production. The order of climate dependence according to the regression models was C > EGCG > TC > EGC > EC > caffeine > ECG > theobromine, indicating seasonal climate had greater effects on flavanols than purine alkaloids.  相似文献   

19.
The aim of this study is to develop an ionic liquid-containing system for efficient production of betulinic acid by cultured cells Armillaria luteo-virens Sacc ZJUQH100-6. Several parameters affecting betulinic acid formation in the IL-containing system were investigated. The addition of [EMIM][BF4] in hexane-containing reaction medium gave rise to better betulinic acid formation in comparison with other ILs used. The optimal concentration of IL in IL-containing co-solvent system is 50% (v/v). As a co-substrate, butanol is found to be useful for intracellular betulin-28-monooxygenase synthesis during the whole phase. The concentrations of substrate and resting cells have been found to exert a significant effect on betulinic acid. Moreover, the reaction time in this IL-containing system was less than that in the conventional one. The effect of the constructed IL-containing system on cell membrane structure was comparatively observed. Under the developed IL-containing system, the highest yield of product observed was 11.14% at 18 h, higher than that in monophase aqueous one (P < 0.05), whereas the activity of monooxygenase showed the same variation as betulinic acid formation.  相似文献   

20.
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