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Nonvolatile components influence overall flavor volatility and perception in alcoholic beverages. However, little information has been reported about the nonvolatile compounds in Chinese distilled spirits. For the first time, we isolated and identified a cyclic lipopeptide “lichenysin” as a novel nonvolatile compound in Chinese liquors, using preparative high performance liquid chromatography coupled with quadrupole‐time‐of‐flight mass spectrometer and nuclear magnetic resonance. The concentrations of lichenysin were quantified in 14 main types of bottled Chinese liquors by using ultra performance liquid chromatography coupled with triple quadrupole mass spectrometer. The concentrations of lichenysin in Chinese liquor ranged from 0.01 to 111.74 μg/L, where the concentration was the highest in Dongjiu liquor. Furthermore, we found that lichenysin selectively affected aroma volatility in the Chinese liquor, using the headspace solid‐phase microextraction coupled with gas chromatography‐mass spectrometry. The headspace concentrations of 2‐phenylethanol, phenol, and 4‐methylphenol significantly decreased by respectively 58%, 76%, and 59% in 3 Chinese commercial liquors with an increase in lichenysin. These results indicated that lichenysin could be a novel nonvolatile compound that selectively affected aroma volatility in Chinese liquors.  相似文献   

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BACKGROUND: A comparative analysis of seed allergens from various soybean genotypes is crucial for identifying and eliminating potential allergens. We have investigated the distribution of three major allergens (Gly m Bd 60K, Gly m Bd 30K and Gly m Bd 28K) in wild, landrace, ancestral and modern soybean genotypes. RESULTS: Gly m Bd 60K allergens consist of α subunits of β‐conglycinin and G2 subunits of glycinin. In wild genotypes, α subunits of β‐conglycinin separated into six to seven protein spots whereas five to seven spots were observed in the landraces. All genotypes of modern and ancestral groups showed 3–5 protein spots of α subunits of β‐conglycinin. All genotypes showed eight spots of glycinin G2 subunits except one ancestral genotype which had seven spots. Two protein spots were detected for Gly m Bd 30K in 14 genotypes but one spot was detected in two wild genotypes. Two protein spots were detected for Gly m Bd 28K in all genotypes. CONCLUSION: Considerable heterogeneity of the α subunit of β‐conglycinin distribution exists among these 16 soybean genotypes. Significant proteomic variation was observed between different soybean groups rather than among genotypes in the same group. This investigation would be valuable to researchers working with soybean and nutrition. Copyright © 2007 Society of Chemical Industry  相似文献   

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1,6-O,O-diacetylbritannilactone (OODBL) isolated from Inula britannica, exhibits potent antitumor activity against several human cancer cell lines. However, the molecular mechanism of OODBL in the induction of anticancer activity is still unclear. In the present study, we demonstrated that OODBL induced the occurrence of apoptosis in human leukemic (HL-60) cells and cell arrest at the S phase. On the other hand, activation of caspase-8, -9, and -3, phosphorylation of Bcl-2 and Bid, and increased release of cytochrome c from mitochondria into cytosolic fraction were detected in OODBL-treated HL-60 cells. We further demonstrated that production of reactive oxygen species (ROS), activation of mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) signaling pathways may play an important role in OODBL-induced apoptosis. The results from the present study highlight the molecular mechanisms underlying OODBL-induced anticancer activity.  相似文献   

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This study conducted in vivo and in situ experiments with rats to investigate the glucagon‐like peptide‐1 (GLP‐1) secretion in response to oral or ileal administration of α‐glucosyl‐isoquercitrin (20–40 mmol in 2 mL; Q3G), fructooligosaccharides (200 mmol in 2 mL; FOS) and Q3G + FOS. Direct effects on GLP‐1‐producing l ‐cells were also examined by an in vitro study using a murine enteroendocrine cell line, GLUTag. To evaluate the plasma GLP‐1 level, blood samples from jugular cannula for in vivo and portal cannula for in situ experiments were obtained before and after administration of Q3G, FOS, or Q3G + FOS. We found tendencies for increases but transient stimulation of GLP‐1 secretion by Q3G in in vivo and in situ experiments. Although FOS alone did not have any effects, Q3G + FOS enhanced and prolonged high plasma GLP‐1 level in both experiments. In addition, application of Q3G on GLUTag cells stimulated GLP‐1 secretion while FOS enhanced the effect of Q3G. Our results suggest that Q3G + FOS possess the potential for the management or prevention of Type 2 diabetes mellitus (T2DM) by enhancing and prolonging the GLP‐1 secretion via direct stimulation of GLP‐1 producing l ‐cell.  相似文献   

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A high-performance liquid chromatography coupled with photodiode-array spectrophotometry and electrospray ionization-mass spectrometry (HPLC-PDA-ESI-MS) method for separation and determination of phenolic acids in ethyl acetate extracts from Chinese waxberry (Myrica Rubra) juice was developed. Total of 4 phenolic acids (ferulic, caffeic, sinapic, and salicylic acids) were identified by comparing their HPLC retention times, UV-Vis absorption spectra, and simultaneously recorded mass spectra with authentic standards. Quantitation was carried out by the peak area method. The calibration curves are linear over the concentration range studied with the correlation coefficients, R(2), greater than 0.99. The contents of ferulic, caffeic, sinapic, and salicylic acids in waxberry juice samples studied were 2.76, 3.58, 2.89, and 1.92 mg/L, respectively, and they occur mainly in bound forms. All relative standard deviations were less than 4%. The recoveries range from 83.6% to 95.8% for the 4 analytes. To the authors' best knowledge, this is the first report for the identification of the sinapic and salicylic acids in Chinese waxberry products.  相似文献   

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Scope: Capsaicin is a cancer‐suppressing agent. The aim of our study was to determine the effect of capsaicin on tumor invasion and migration; the possible mechanisms involved in this inhibition were investigated in human fibrosarcoma cells. Methods and results: We employed invasion, migration and gelatin zymography assays to characterize the effect of capsaicin on HT‐1080 cells. Transient transfection assays and immunoblot analysis were performed to study its molecular mechanisms of action. Capsaicin inhibited the epidermal growth factor (EGF)‐induced activation of matrix metalloproteinase (MMP)‐9 and MMP‐2, and further inhibited cell invasion and migration. Capsaicin decreased the EGF‐induced expression of MMP‐9, MMP‐2, and MT1‐MMP, but did not alter TIMP‐1 and TIMP‐2 levels. Capsaicin suppressed EGF‐induced c‐Jun and c‐Fos nuclear translocation, and also abrogated the EGF‐induced phosphorylation of EGF receptor (EGFR), focal adhesion kinase (FAK), protein kinase C (PKC), phosphatidylinositol 3‐Kinase (PI3K)/Akt, extracellular regulated kinase (ERK)1/2, and JNK1/2, an upstream modulator of AP‐1. Furthermore, the EGFR inhibitor inhibited EGF‐induced MMP‐9 expression, as well as AP‐1 activity and cell migration. Conclusion: Capsaicin inhibited the EGF‐induced invasion and migration of human fibrosarcoma cells via EGFR‐dependent FAK/Akt, PKC/Raf/ERK, p38 mitogen‐activated protein kinase (MAPK), and AP‐1 signaling, leading to the down‐regulation of MMP‐9 expression. These results indicate the role of capsaicin as a potent anti‐metastatic agent, which can markedly inhibit the metastatic and invasive capacity of fibrosarcoma cells.  相似文献   

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Aronia melanocarpa is a rich source of phenolic compounds like anthocyanins, chlorogenic acids, quercetin derivatives, and proanthocyanidins possessing strong antioxidative potential. The consumption of A. melanocarpa is actually increasing because of the known bioactivity of its phenolic constituents. A. melanocarpa extracts are used as natural colorants and nutraceuticals. Several attempts of adulteration of aronia products have already been reported. In this study, we investigated changes in phenolic composition from berry to juice by HPLC‐PDA, and HPLC‐ESI‐MSn analyses as well as fingerprint profiles for authentication of commercially available aronia products in order to detect possible adulteration. Additionally, the radical scavenging activity of aronia products was determined by using the TEAC (Trolox® equivalent antioxidant capacity) assay. Aronia pomace, a valuable by‐product of juice production, showed the highest phenolic content and possessed the highest radical scavenging activity.  相似文献   

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Polyphenols of plant origin have received special interest in the last decade because of their potential health benefits. Consequently, many beverages with words ‘antioxidant’ and ‘polyphenols’ have been developed. However, many of the claims are misleading because some beverages so labelled have either no or minimal levels of polyphenols. The objectives of this study were to quantify polyphenols (TPC) and ascorbic acid contents and antioxidant capacity (AOC) of different beverages; identify major polyphenols in beverages that showed higher TPC; correlate the claim on the label with TPC and AOC; and determine the impact of consumer refrigerated storage on TPC and AOC of aronia, blackcurrant and pomegranate juices which contained the most TPC and AOC. Major polyphenols identified from these juices included anthocyanins, myricetin and epicatechin. TPC of aronia, blackcurrant and pomegranate juices was relatively stable during consumer refrigerated storage, even when the juice had been intermittently exposed to air.  相似文献   

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Carrots were analysed for taste and odour and for contents of terpenes, 6‐methoxymellein and sugars during 3 weeks storage at 15 °C in an atmosphere containing ethylene (1 µl l−1). The ethylene treatment caused an increase in 6‐methoxymellein and the conversion of higher amounts of sucrose to fructose and glucose compared to control carrots stored in air. This corresponded to higher sensory scores for bitterness and terpene flavour and a lower score for sweetness, as measured by an expert taste panel. Principal component analysis showed a more expressed bitter taste, earthy flavour, green flavour, terpene flavour and aftertaste in the ethylene‐treated carrots. Correlations were found between sweet taste and the content of sucrose (r = 0.91, p < 0.005) and between the contents of various terpenes (particularly γ‐terpinene, limonene and caryophyllene) and terpene flavour, green flavour, aftertaste and bitter taste (r ≥ 0.72, p < 0.05). In the air‐stored carrots these off‐flavours seemed to be masked by a high sucrose content. © 2000 Society of Chemical Industry  相似文献   

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