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1.
There has been much interest in the potential of using probiotic bacteria for treating allergic diseases. A double-blind, placebo-controlled study was conducted to examine the effectiveness of Lactobacillus GG (LGG) and L. gasseri TMC0356 (TMC0356) in alleviating Japanese cedar pollinosis (JCP), a seasonal allergic rhinitis caused by Japanese cedar pollen. Fermented milk prepared with the tested bacteria or placebo yoghurt was administered to 40 subjects with a clinical history of JCP for 10 weeks. Subjective symptoms, self-care measures and blood samples were compared between the two groups. Peripheral blood mononuclear cells (PBMCs) were collected from seven patients with JCP and in vitro cytokine production by the isolated PBMCs was analysed in the presence of heat-killed lactic acid bacteria. Consumption of the fermented milk significantly decreased the mean symptom score for nasal blockage after 9 weeks (P<0.05) and mean symptom-medication scores after 9 and 10 weeks when compared with the placebo group (P<0.01 and P<0.05 respectively). The tested strains of lactic acid bacteria affected cytokine production by isolated PBMCs in vitro in a strain-dependent manner. LGG significantly inhibited IL-4 and IL-5 production by PBMCs stimulated by both Cry j 1 and PHA. TMC0356 only suppressed IL-5 production stimulated by PHA. The fermented milk prepared with LGG and TMC0356 might be beneficial in JCP because of its effect on nasal blockage. The effects of LGG and TMC0356 might arise at least partly from their specific down-regulation of the human Th2 immune response.  相似文献   

2.
Lactic acid bacteria (LAB) represent an attractive delivery vehicle for oral allergy vaccine because of their safety as a food microorganism as well as their potent adjuvant activity triggering anti-allergic immune response. Here, we report the generation of recombinant LAB expressing a major Japanese cedar pollen allergen Cry j 1 (Cry j 1-LAB), and their prophylactic effect in vivo. To facilitate heterologous expression, the codon usage in the Cry j 1 gene was optimized for the host LAB strain Lactobacillus plantarum by the recursive PCR-based exhaustive site-directed mutagenesis. Use of the codon-optimized Cry j 1 cDNA and a lactate dehydrogenase gene fusion system led to a successful production of recombinant Cry j 1 in L. plantarum NCL21. We also found that oral vaccination with the Cry j 1-LAB suppressed allergen-specific IgE response and nasal symptoms in a murine model of cedar pollinosis.  相似文献   

3.
比较不同微波处理条件下毛豆仁POD 酶活变化,建立微波处理功率、时间、料水比与POD 酶活的数学回归模型。通过响应面优化出最佳灭酶工艺参数:在微波功率650W、料水比2:1(g/mL)条件下处理80s,检测不到POD 酶活,且感官、营养品质较佳。结果显示:与传统热水烫漂相比,在有效钝化POD 酶活的前提下,VC 损失率下降14.02%,叶绿素损失率下降11.43%,粗脂肪和蛋白质含量无显著变化。  相似文献   

4.
给糖尿病大鼠口服蔗糖或淀粉和绿茶提取物后,观察其对糖尿病大鼠糖耐量及血胰岛素的影响,并用比色法测定对α-葡萄糖苷酶(EC 3.2.1.20)和α-淀粉酶(EC 3.2.1.1)的抑制活性,用快速过滤法观察对兔小肠刷状缘囊泡葡萄糖转运活性的影响.结果表明,绿茶提取物明显改善蔗糖或淀粉负荷糖尿病大鼠的血糖水平.绿茶提取物显示较强的α-葡萄糖苷酶抑制活性,其α-葡萄糖苷酶的半抑制浓度(IC50)值为0.13g/L;对α-淀粉酶的抑制活性则较弱,浓度为1g/L时,其对α-淀粉酶的抑制率为21%.绿茶提取物同时明显降低兔小肠刷状缘囊泡葡萄糖转运能力,其半抑制浓度(IC50)值为3.5g/L.提示,绿茶可延缓小肠对糖的消化吸收,经常食用可能有助于延缓餐后血糖的持续升高. C 3.2.1.1)的抑制活性,用快速过滤法观察对兔小肠刷状缘囊泡葡萄糖转运活性的影响.结果表明,绿茶提取物明显改善蔗糖或淀粉负荷糖尿病大鼠的血糖水平.绿茶提取物显示较强的α-葡萄糖苷酶抑制活性,其α-葡萄糖苷酶的半抑制浓度(IC50)值为0.13g/L;对α-淀粉酶的抑制活性则较弱,浓度为1g/L时,其对α-淀粉酶的抑制率为21%.绿茶提取物同时明显降 兔小肠刷状缘囊泡葡萄糖转运能力,其半抑制浓度(IC50)值为3.5g/L.提示,绿茶可延缓小肠对糖的消化吸收,经常食用可能有助于延缓餐后血糖的持续升  相似文献   

5.
Furus, Chinese traditional soybean products, which are salted, fermented and seasoned bean curd preserved in dipping sauce, were studied for their anti-mutagenic and anti-oxidative activities. There are many varieties of furu by region, depending on their ingredients and bacterial strain used. Furus, not only have peculiar palatable taste and aroma, but also present strong anti-oxidative activity which ordinary Japanese soybean curd, tofu, never shows. Against benzo(α)pyrene, all samples, regardless of solid or dipping sauce, showed anti-mutagenic activity. In general, red furus had higher activity than white. All red furus inhibited more than 50% of the mutagenicity and this high suppressive ratio suggested that it was raised mainly by secreted substances discharged from the bacterial body rather than by functional compounds originating from soybeans. In the case of white furu, which showed wide differences in activity, the functional role of each spice and condiment added needs to be further studied, in addition to the soybean and white furu ferment-rice malt.  相似文献   

6.
Chemical analysis of Allium caepa L. var Tropeana (red onion) seeds showed high amounts of oil (20.4%), fibre (22.4%), crude protein (24.8%), calcium (175.0 mg/100 g), potassium (1010 mg/100 g), low amounts of sodium (11.2 mg/100 g) and six cysteine derivatives, of which the S-propylmercapto-cysteine has never been reported in onion before. The antioxidant capacity of seed extracts containing cysteine derivatives (SECCD), before and after boiling the seeds, and of cooking water extracts containing cysteine derivatives (CWECCD), was also evaluated, by the ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrilhydrazyl (DPPH) assays. The extracts showed discrete antioxidant capacity which increased after boiling, although cooking methods caused significant losses of the cysteine derivatives in water.  相似文献   

7.
Yu-Hsiang Hung 《LWT》2009,42(1):56-5033
Aspergillus awamori-fermented black soybeans, a potential healthy food ingredient, possess antimutagenicity against 4-nitroquinoline-N-oxide (4-NQO); a direct mutagen and benzo[a]pyrene (B[a]P; an indirect mutagen). Results of this study revealed that antimutagenic, desmutagenic, and blocking effects all contributed to the antimutagenicity of the methanol of fermented black soybean. However, the desmutagenic effect of the fermented black soybean extract on B[a]P is not caused by the interaction of intact B[a]P or S9 mixture with the extract. Instead, it is due to the interaction of B[a]P metabolites with the antimutagenic factors in the extract. Exposure to simulated gastric juice (pH 1.2) for 30 min or intestinal juice for 2 h resulted in a reduced antimutagenicity of fermented black soybean extract. Nevertheless, the simulated gastric juice treated-fermented black soybean extracts and the simulated intestinal juice treated-fermented black soybean extracts still possessed a considerable antimutagenic effect against 4-NQO and B[a]P.  相似文献   

8.

为研究臭氧微纳米气泡(ozone micro-nano-bubbles,Ozone MNBs)处理黄豆芽对LED白光照射下黄豆芽“绿化”的影响及其调控机制,本实验以黄豆芽为材料,采用4 mg/L Ozone MNBs处理黄豆芽,测定LED白光照射下黄豆芽生理品质,叶绿素合成和分解相关酶及物质变化。结果表明:与蒸馏水处理对照组相比,4 mg/L Ozone MNBs处理可以显著降低LED白光照射下黄豆芽的“绿化”现象,诱导提高黄豆芽中叶绿素降解酶[叶绿素酶(Chlase)、叶绿素降解过氧化物酶(Chl-POX)、脱镁螯合酶(MD)和脱镁叶绿素酶(PPH)]活性,降低了叶绿素合成前体物[δ-氨基乙酰丙酸(ALA)和尿卟啉原Ⅲ(Urogen Ⅲ)],叶绿素、叶绿素a(Chl a)和叶绿素b(Chl b)含量。降低了ADP、ATP和辅酶Ⅱ[NADP+和NADPH]含量。4 mg/L Ozone MNBs处理可影响黄豆芽叶绿素合成和分解相关酶的活性和相关物质的含量,对抑制LED白光照射下黄豆芽“绿化”有较好的效果。

  相似文献   

9.
Renal cell carcinoma (RCC) is one of the most lethal amongst the urologic malignancies, comprising three percent of all human neoplasms, and its incidence appears to be rising. RCC is refractory to both chemotherapy and radiotherapy. Therefore, the discovery of new strategies for therapeutic intervention remains a priority. Green tea (Camellia sinensis) and tea polyphenols have been proposed to exert protective effects against several types of cancer, based on preclinical and clinical trial data; however, the anticarcinogenic activity of green tea towards RCC is unknown. In this study, a targeted metabolite analysis on a green tea leaves methanolic extract was performed by HPLC/DAD and the antiproliferative activity of the extract was assayed using human renal cancer cell lines A-498 and 769-P. The total phenolic content was very high (31.8% of methanolic extract), and the main compounds were flavan-3-ols (94.3% of the total phenolic content), and especially (−)-epigallocatechin-3-gallate (35.9% of the total phenolic content). In addition, two methylxanthines – theophylline and caffeine – were also present in the extract, caffeine being the most abundant. Green tea extract strongly inhibited the growth of both RCC cell lines in a concentration-dependent manner, with IC50 values of 54 ± 10 and 129 ± 28 μg/ml for A-498 and 769-P cells, respectively. This is the first report showing that green tea is likely to be an effective anticancer agent for renal cell carcinoma.  相似文献   

10.
In the present work, the antimicrobial activity of different pressurized liquid extracts obtained from Haematococcus pluvialis microalga was tested against several microorganisms of importance for the food industry (Escherichia coli, Staphylococcus aureus, Candida albicans and Aspergillus niger). Extractions were performed with hexane and ethanol at four different temperatures (50, 100, 150 and 200 °C) for 20 min. The results showed that extracts obtained with both solvents (hexane and ethanol) from the green motile cells of the microalgae (green phase) presented a low antimicrobial activity against all the microorganisms tested. However, the antimicrobial activity of the extracts obtained from the red hematocysts without flagella (red phase) was totally different depending on the solvent used for the extraction. Hexane extracts showed an antimicrobial activity quite similar to that obtained with the green microalgae, while the antimicrobial activity of ethanol extracts was much higher. This fact seems to indicate that compounds related to antimicrobial activity of this microalga are found in higher quantities in the red phase of the microalgae and could be relatively polar compounds. Moreover, ethanol extracts from the red phase obtained at 100 °C presented the highest antimicrobial activity. In order to identify the compounds responsible for the antimicrobial activity, a GC-MS characterization of the extracts obtained with both hexane and ethanol at 100 °C, for Haematococcus pluvialis in the green and red phases was also performed. Therefore, the highest antimicrobial activity of the ethanol extract corresponding to red Haematococcus can be associated with the presence in this extract of short-chain fatty acids, which have been previously described to possess antimicrobial activity.  相似文献   

11.
Acacia confusa Merr. (Leguminosae), a species native to Taiwan, is widely distributed on the hills and lowlands of Taiwan, and has been traditionally used as a medicine. In this study, phytochemicals and antioxidant activities of hot water extracts from A. confusa leaves were investigated for the first time. Among all the fractions from hot water extracts of leaves, the EtOAc-soluble fraction exhibits the best DPPH radical-scavenging activity, superoxide radical-scavenging activity, and reducing power. In addition, a rapid screening method, on-line RP-HPLC-DPPH system, for individual antioxidants in the EtOAc-soluble fraction was developed. Furthermore, following solid phase extraction (SPE) and reverse-phase high-performance liquid chromatography 12 pure phenolic compounds, including five major compounds (gallic acid, (+)-catechin, (−)-epicatechin, myricetin 3-glucopyranoside, and myricetin 3-rhamnopyranoside) were detected using the developed screening method. These results demonstrated that hot water extracts of A. confusa leaves have excellent antioxidant activities and thus have great potential as a source for natural health products.  相似文献   

12.
目的:研究卡亚茶水提物的辅助降血脂作用。方法:将50只小鼠随机分成空白对照组(普通饲料)、阴性对照组(高脂饲料)和高、中、低剂量组(卡亚茶水提取物+高脂饲料),分笼喂养30d,测定小鼠体重、肝重、肝脏指数、血清总胆固醇(TC)、血清三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)和高密度脂蛋白胆固醇(HDL-C),并观察肝脏组织病理学变化。结果:卡亚茶水提取物可缓解高脂饲料喂养小鼠体重、肝重和肝脏指数的增加,降低高脂小鼠肝组织中脂肪细胞量,中剂量组小鼠血清TC、TG和LDL-C显著低于阴性对照组(p<0.05),HDL-C显著高于阴性对照组(p<0.05)。结论:适当浓度的卡亚茶水提取物有辅助降血脂作用。  相似文献   

13.
Thirty-three plants used in cooking for aroma and taste were examined for antibacterial activity against pathogens causing foodborne infections. Vibrio parahaemolyticus and Staphylococcus aureus were sensitive to many kinds of plant extracts, whereas Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Enteritidis populations decreased in only six, one, and three plant extracts, respectively. The polyphenol content in the plants was significantly different between the antibacterial plants and nonantibacterial plants, indicating that the polyphenols were related to the antibacterial action of these plants. Antibacterial activity of various concentrations of leaf extracts from Japanese persimmon, white cedar, and grape were investigated. Japanese persimmon and white cedar leaf extracts at low concentrations affected L. monocytogenes and V. parahaemolyticus rapidly. With grape leaf extract at low concentrations, the population of L. monocytogenes decreased similarly to Japanese persimmon and white cedar leaves. This study demonstrates that many plants used in cooking for aroma and taste contain polyphenols and exhibit antibacterial activity against foodborne pathogens.  相似文献   

14.
目的:通过动物实验、体外实验确认食用香甜味沙拉酱对β-胡萝卜素吸收的影响效果。方法:采用高效液相色谱(high performance liquid chromatography,HPLC)技术进行β-胡萝卜素定量分析;参考93号饲料(AIN-93)配方,分组连续喂养大鼠12 d,测定不同组别大鼠肝脏中β-胡萝卜素的含量;配制人工胃液,分别将磨碎的芒果与香甜味沙拉酱和大豆油混合,模拟胃液蠕动搅拌不同时间,并测定油相中β-胡萝卜素含量;分别给大鼠灌胃等量的β-胡萝卜素以及油量相等的香甜味沙拉酱与大豆油,比较香甜味沙拉酱与大豆油在大鼠胃中停留的时间并测定油相中β-胡萝卜素含量。结果:大鼠肝脏中β-胡萝卜素含量为香甜味沙拉酱组大豆油组(P0.05);体外模拟实验发现,芒果更容易分散于香甜味沙拉酱体系,油相中β-胡萝卜素含量为香甜味沙拉酱组大豆油组,搅拌60 min组搅拌30 min组(P0.05);大鼠在灌胃30 min后胃液中β-胡萝卜素含量为香甜味沙拉酱组大豆油组(P0.05),且香甜味沙拉酱在胃中停留的时间更长。结论:食用香甜味沙拉酱比单纯食用大豆油更能够促进β-胡萝卜素的吸收转化;香甜味沙拉酱更能促进富含β-胡萝卜素水果中的β-胡萝卜素的吸收。  相似文献   

15.
Aqueous extracts from 20 Malaysian edible plants were screened for total phenolic content (TPC), antioxidant activity and genotoxic effects on freshly isolated human lymphocytes. Ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assays were performed to determine the antioxidant activity of the extracts. Single-cell gel electrophoresis (SCGE) or comet assay was carried out to determine the level of DNA damage in human lymphocytes. Of the 20 plant aqueous extracts tested, two exerted more than 50% DNA strand breaks (severe damage), nine exerted 25–50% strand breaks (moderate damage) and nine exerted <25% strand breaks (mild damage). Strong positive correlations between the extent of DNA damage and FRAP level (r = 0.816), DNA damage and TPC (r = 0.830) and DNA damage and DPPH radical scavenging activities (r = 0.859) were observed. It is evident from this study that plants rich in antioxidants have greater genotoxic effect.  相似文献   

16.
This study describes the potential use of New Zealand seaweed extracts as antioxidants in fish oils. The extracts from two brown seaweeds (Ecklonia radiata, Macrocystis pyrifera) and two red species (Champia sp. and Porphyra sp.), were added to hoki (Macruronus novaezelandiae) oil and assessed by production of oxidation products in an elevated temperature (60 °C) storage trial. Antioxidant assays ORAC and DPPH were conducted to elucidate the radical scavenging activity of the seaweed extracts. The results showed that all the lipid-soluble seaweed extracts had some antioxidative capacity, with brown algae generally outperforming red algae species. Extracts from E. radiata performed best with significantly lower primary, secondary and total oxidation products, and higher DPPH radical scavenging ability than the commercial antioxidant, BHT. This study demonstrated the potential of brown algae seaweed extracts, in particular E. radiata, for use as antioxidants in fish oil products.  相似文献   

17.
This study provides a new strategy to detect the specific carbohydrate binding capability of lectins. A sugar-polymer based enzyme-linked adsorbent assay was established by applying different monosaccharide–polyacrylamide conjugates as capturing agents for screening lectins in biological samples. Four model lectins, concanavalin A (Con A), wheat germ agglutinin (WGA), soybean agglutinin (SBA) and Ulex europaeus agglutinin I (UEA I), were employed as the comparative lectins against each corresponding sugar. The results suggested that this assay is more sensitive than the conventional hemagglutinating methods. On the screening of specific carbohydrate binding capability from biological materials, extracts of papaya (Carica papaya) seeds, longan (Euphoria longana) seeds and sorghum (Sorghum bicolor) were shown various specific monosaccharide binding capabilities which had not been reported before. In conclusion, the assay provides an alternative and efficacious detection for the specific carbohydrate binding substances in biological samples.  相似文献   

18.
Flavour-enhancing components of dried herring fillet (migaki-nishin in Japanese) were isolated and evaluated for their effects on sensory perception. Sensory evaluation revealed that addition of dried herring fillet water-soluble extracts to Japanese noodle soup significantly (P < 0.05) enhanced soup flavour characters, such as thickness, mouthfulness and continuity. The extracts were fractionated by dialysis and chromatography. Fractions containing flavour enhancers were isolated by sensory perception. Results from instrumental analyses showed that the kokumi flavour enhancers in dried herring fillet were creatine and creatinine.  相似文献   

19.
Food allergy has become a public health problem that continues to challenge both the consumer and the food industry. The objectives of this study were to evaluate the reduction of immunoreactivity by natural and induced fermentation of soybean meal (SBM) with Lactobacillus plantarum, Bifidobacterium lactis, Saccharomyces cereviseae, and to assess the effect on amino acid concentration. Immunoreactivity of commercially available fermented soybean products and ingredients was also evaluated. ELISA and western blot were used to measure IgE immunoreactivity using plasma from soy sensitive individuals. Commercial soy products included tempeh, miso and yogurt. Fermented SBM showed reduced immunoreactivity to human plasma, particularly if proteins were <20 kDa. S. cereviseae and naturally fermented SBM showed the highest reduction in IgE immunoreactivity, up to 89% and 88%, respectively, against human pooled plasma. When SBM was subjected to fermentation with different microorganisms, most of the total amino acids increased significantly (p < 0.05) and only few of them suffered a decrease depending on the type of fermentation. All commercial soy containing products tested showed very low immunoreactivity. Thus, fermentation can decrease soy immunoreactivity and can be optimized to develop nutritious hypoallergenic soy products. However, the clinical relevance of these findings needs to be determined by human challenge studies.  相似文献   

20.
《Journal of dairy science》2022,105(3):2343-2353
We examined the effects of substituting soybean meal with either yeast protein from Cyberlindnera jadinii or barley in concentrate feeds on feed intake, ruminal fermentation products, milk production, and milk composition in Norwegian Red (NRF) dairy cows. The concentrate feeds were prepared in pellet form as soy-based (SBM; where soybean meal is included as a protein ingredient), yeast-based (YEA; soybean meal replaced with yeast protein), or barley-based (BAR; soybean meal replaced with barley). The SBM contained 7.0% soybean meal on a dry matter (DM) basis. This was replaced with yeast protein and barley in the YEA and BAR concentrate feeds, respectively. A total of 48 early- to mid-lactation [days in milk ± standard deviation (SD): 103 ± 33.5 d] NRF cows in their first to fourth parity and with initial milk yield of 32.6 kg (SD = 7.7) were allocated into 3 groups, using a randomized block design, after feeding a common diet [SBM and good-quality grass silage: crude protein (CP) and neutral detergent fiber (NDF) content of 181 and 532 g/kg of DM, respectively] for 14 d (i.e., covariate period). The groups (n = 16) were then fed one of the dietary treatments (SBM, YEA, or BAR) for a period of 56 d (i.e., experimental period). The concentrate feeds were offered in split portions from 3 automatic feeders using electronic identification, with ad libitum access to the same grass silage. Dietary treatments had no effect on daily silage intake, total DM intake, or total NDF intake. Dietary CP intake was lower and starch intake was higher in the BAR group compared with the other groups. Ruminal fluid pH, short-chain volatile fatty acid (VFA) concentrations, acetate-to-propionate ratio, and non-glucogenic to glucogenic VFA ratio were not affected by dietary treatments. No effects of the dietary treatments were observed on body weight change, body condition score change, milk yield, energy-corrected milk yield, milk lactose and fat percentages, or their yields. In conclusion, yeast protein can substitute conventional soybean meal in dairy cow diets without adverse effect on milk production and milk composition, given free access to good-quality grass silage.  相似文献   

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