共查询到20条相似文献,搜索用时 11 毫秒
1.
Freeze drying (FD) yields the best quality of dried sea cucumber but at the cost of long drying time and also the overall cost. Air drying (AD) gives an unacceptably poor quality product. To achieve faster drying along with a high quality product a microwave freeze drying (MFD) technique was developed to dry sea cucumbers. The relationship between corona discharge and microwave power at various pressures and initial moisture content conditions was studied to avoid the possibility of corona discharge during MFD. According to the drying characteristics of MFD, a control strategy for the MFD process was also developed. MFD reduced the drying time by about half of conventional FD process and provided a similar good product quality. 相似文献
2.
Two-dimensional numerical simulations were carried out to describe the lyophilization process at atmospheric pressure and its optimization. The finite differences method succeeded in describing correctly the complex motion of the sublimation interface in foodstuff. Comparison of unidirectional and bidirectional mass and energy transport showed considerable differences in the drying kinetics. These differences decreased as the geometric ratio (GR) decreased and the physical situation approached to that of an infinite plate. The temperature and vapor pressure distributions were analyzed as functions of ice saturation. Two-dimensional numerical simulations showed a good fit with the experimental data. 相似文献
3.
This study determined the hypocholesterolaemic effects of chitosan preparations with different physicochemical properties. Chitosans with smaller particle size had better cholesterol-binding capacities. Chitosans exhibited potent hypocholesterolaemic effect in rats; those with higher degree of deacetylation and molecular weight seemed to reduce plasma triglyceride, total cholesterol and low-density-lipoprotein cholesterol levels and elevate the high-density-lipoprotein cholesterol level more effectively, although not all differences were significant. We concluded that the hypocholesterolaemic mechanism of chitosan was by adsorption, electrostatic force and entrapment. 相似文献
4.
Lillian Barros Montserrat DueñasMaria Inês Dias Maria João SousaCelestino Santos-Buelga Isabel C.F.R. Ferreira 《Food chemistry》2012,132(2):841-848
Coriandrum sativum L. is a source of a variety of polyphenols and other phytochemicals, related to its high antioxidant activity and to its use for indigestion, rheumatism, and prevention of lipid peroxidation damage. Plant cell cultures are a means to study or to produce some active metabolites, such as polyphenols. This technique was applied to the investigation of coriander, and a detailed analysis of individual polyphenols in vivo and in vitro grown samples was performed. The in vivo vegetative parts showed quercetin derivatives as the main flavonoids and quercetin-3-O-rutinoside (3296 mg/kg dw) was the main polyphenol found in this part of coriander. The fruits revealed only phenolic acids and derivatives, caffeoyl N-tryptophan hexoside (45.33 mg/kg dw) being the most abundant phenolic derivative. In vitro samples also gave a high diversity of polyphenols, being C-glycosylated apigenin (2983 mg/kg dw) the main compound. Anthocyanins were only found in clone A, which was certainly related to its purple pigmentation, and peonidin-3-O-feruloylglucoside-5-O-glucoside was the major anthocyanin found (1.70 μg/kg dw). In vitro culture can be used to explore new industrial, pharmaceutical, and medicinal potentialities, such as the production of secondary metabolites like flavonoids. 相似文献
5.
Hui-Hsuan Lin Kuei-Chuan Chan Jenn-Yuan SheuShu-Wen Hsuan Chau-Jong Wang Jing-Hsien Chen 《Food chemistry》2012,132(2):880-891
Hibiscus sabdariffa leaf, the edible part of H. sabdariffa Linne, is usually ignored and discarded. The object of the study was to examine the anticancer properties of H.sabdariffa L. leaf extract (HLE). First, HLE was demonstrated to be rich in polyphenols, including catechin and ellagic acid (EA). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) data showed that among three kinds of human prostate cancer (CaP) cells, androgen-dependent LNCaP cells were the most susceptible to HLE. HLE and its purified compound EA were evaluated for apoptotic activities. Molecular data showed the effect of HLE in LNCaP cells might be mediated via both intrinsic and extrinsic apoptotic pathways. Finally, HLE inhibited the growth of LNCaP cells in xenograft tumour studies. As a result, our data presented the first evidence of HLE as an apoptosis inducer in LNCaP cells, and these findings may open interesting perspectives to the strategy in human CaP treatment. 相似文献
6.
Demétrius Paiva Arçari Juliana Carvalho Santos Alessandra Gambero Marcelo Lima Ribeiro 《Food chemistry》2013
The aim of this study was to evaluate the effects of yerba mate extract and its principal bioactive compounds on adipogenesis. The anti-adipogenic effects of yerba mate, chlorogenic acid, quercetin and rutin were evaluated in 3T3-L1 cells using a PCR array. The results obtained in vitro were validated in vivo in a high-fat diet-induced model of obesity. The in vitro and in vivo results demonstrated that yerba mate extract down-regulated the expression of genes that regulate adipogenesis, such as Creb-1and C/EBPα, and the extract up-regulated the expression of genes related to the inhibition of adipogenesis, including Dlk1, Gata2, Gata3, Klf2, Lrp5, Pparγ2, Sfrp1, Tcf7l2, Wnt10b, and Wnt3a. In summary, it was demonstrated that yerba mate and its bioactive compounds regulate the expression of genes related to in vitro adipogenesis. Furthermore, yerba mate might regulate adipogenesis through the Wnt pathway. 相似文献
7.
Salvador Fernández-Arroyo Inmaculada C. Rodríguez-Medina Raúl Beltrán-DebónFederica Pasini Jorge JovenVicente Micol Antonio Segura-Carretero Alberto Fernández-Gutiérrez 《Food research international (Ottawa, Ont.)》2011,44(5):1490-1495
In the present study the quantification of the polyphenolic fraction, anthocyanins and other polar compounds, the antioxidant capacity and the anti-hyperlipemic action of the aqueous extract of Hibiscus sabdariffa has been achieved. Seventeen compounds were successfully quantified either by HPLC-DAD or HPLC-ESI-TOF-MS. Six of them were directly quantified by their corresponding standards, whereas the rest were indirectly quantified as equivalents using standards of similar compounds. The antioxidant capacity have also been estimated by comparing different assays, i,e, Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and measurement of thiobarbituric acid reacting substances (TBARS). H. sabdariffa showed high reducing capacity in FRAP assay and significant capability to scavenge peroxyl radicals in the ORAC assay. Nevertheless, the extract exhibited poor efficacy to inhibit peroxyl radicals in lipid systems. The plant extract also exhibited the capacity to decrease serum triglyceride concentration on hyperlipemic mouse model. 相似文献
8.
Xiaowei Shi Man Liu Min Zhang Kerong Zhang Songchen Liu Shi Qiao Rui Shi Xijuan Jiang Qiao Wang 《Food chemistry》2013
The objective of the present study was to develop a practical strategy for the identification of metabolites following the in vivo metabolism and in vitro microbial biotransformation of isoimperatorin using liquid chromatography hybrid triple quadrupole-linear ion trap mass spectrometry (LC/QTRAP–MS) and liquid chromatography time of flight mass spectrometry (LC/TOF–MS). As a result, 19 metabolites were characterised in rat urine, plasma, bile and faeces after the oral administration of isoimperatorin and 13 products were identified in the sample from the transformation. Four metabolites were prepared by in vitro microbial biotransformation, and one was confirmed to be a novel compound. The side chain of isoimperatorin was found to be the primary metabolic site that underwent oxidation metabolism both in vivo and in vitro, and the metabolism of isoimperatorin in vivo and in vitro has good correlation. This is the first study of the metabolism of isoimperatorin in vivo. 相似文献
9.
Tomoko Sasaki Kaoru Kohyama Yasuhiro Suzuki Kazuyuki Okamoto Timothy R. Noel Steve G. Ring 《Food chemistry》2009
Starches were isolated from three waxy rice varieties: Koganemochi (Kog), Hakuchomochi (Hak), and Kantomochi 172 (K172). Forty percent starch gels were prepared and the extent of starch gel digestibility was determined by an in vitro method. The distribution of chain lengths of amylopectin was analyzed and differential scanning calorimetry was used to analyze gelatinization and retrogradation of waxy rice starch. The K172 gel had significantly higher resistance to hydrolysis than had the other gels. The K172 starch contained lower proportions of the short chains of amylopectin and showed higher gelatinization temperature and enthalpy. The retrogradation peak was measured using waxy rice starch gels stored for 1 and 7 days at 5 °C. The K172 gel was observed to retrograde more quickly and to have a greater extent of retrogradation than the other gels. The difference in amylopectin chain length distribution and recrystallinity contributed to the variation in the starch gel digestibility of waxy rice. 相似文献
10.
The in vitro and in vivo protective effects of water extract of pu-erh tea (WEPT) on tert-butyl-hydroperoxide (t-BHP)-induced oxidative damage in hepatocytes of HepG2 cells and in rat livers were investigated. After treatment with 200 μg/ml of samples, the survival rate of HepG2 cells induced by t-BHP increased. WEPT concentration-dependently inhibited reactive oxygen species (ROS) generation in HepG2 cells in response to the oxidative challenge induced by t-BHP. Administration of WEPT (0.2, 0.5 and 1.0 g/kg of body weigh) to rats for 56 consecutive days before a single dose of t-BHP (0.5 mmol/kg, i.p.) exhibited a significant (p < 0.01) protective effect by lowering serum levels of glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT), as well as reducing the formation of malondialdehyde. Taken together, these results demonstrate that WEPT is able to protect against hepatic damage in vitro and in vivo, suggesting that the drinking of pu-erh tea may protect liver tissue from oxidative damage. 相似文献
11.
Rickard Öste Per Sjödin Margaretha Jägerstad Inger Björck Arne Dahlqvist 《Food chemistry》1985,16(1):37-47
The effect of Maillard reaction products on the digestion of carbohydrates was studied. Low molecular weight compounds from a glucose—lysine model reaction mixture were weak competitive inhibitors of lactase, invertase, maltase and trehalase in vitro, when tested at concentrations of 5–10 mg/ml. High molecular weight compounds from the reaction mixture were strong inhibitors of the same disaccharidases at considerably lower concentrations (1·4–2·8 mg/ml). However, when fed to growing rats in amounts up to 40 mg, the high molecular weight compounds failed to reduce the uptake of intubated lactose or sucrose. α-Amylase was not at all affected. 相似文献
12.
Hso-Chi Chaung Chin-Dong Chang Pi-Hang Chen Chia-Jung Chang Shyh-Hwa Liu Chih-Cheng Chen 《Food chemistry》2013
Fish oil during early postnatal period may modulate the impact of oxidative stress in the developing brain and thus improve memory and cognitive behaviour. This study investigated the impacts of docosahexaenoic acid (DHA, C22:6, n-3) and/or phosphatidylserine (PS) on antioxidant activities in vitro, and the beneficial effects of feeding with DHA and/or PS on antioxidant activities in brain and liver tissues and on the cognitive functions of the developing brain. Results indicated that DHA and/or PS significantly enhanced antioxidant activities and increased cell viabilities in vitro. Feeding with DHA and/or PS supplementation not only significantly improved escape latency of animals, but it also improved the oxidative parameters in the brain, enhanced glutathione peroxidase activity as well as reduced nitric mono-oxide levels in the liver. DHA and PS may serve to protect cells from oxidative stress and further improve learning and memory ability in vivo. 相似文献
13.
Wenwei Zhang Shijia Liu Yihua Wang Leina Zheng Feng Liu Xiaohua Han Yulong Ren Qizhang Long Zhigang Zhao Ling Jiang Jianmin Wan 《Food chemistry》2010
Protein digestibility was determined in 18 indica and japonica raw milled rices using an in vitro pH-drop method with three- or four-enzyme system. Similar protein digestibility was found between indica and japonica rices, which is in agreement with the in vivo digestibilities in human. Cooking improved protein digestibility in the four-enzyme assay, while reducing agents exhibited apparent inhibition in multienzyme digestibility of indica and japonica rices. A significant correlation was detected between protein content and the estimates of digestibility, whereas no significant correlation was found between amylose content and digestibility estimates. SDS–PAGE analysis showed a significant difference in the degradation extent of prolamin between multienzyme and pepsin digestion, which might contribute to the inconsistence between results of this study and previous findings that in vitro protein digestibility of japonica rice was higher than that of indica rice. In addition, our results supported the previous report that waxy gene product level is not a major determinant of protein digestibility in milled rice. 相似文献
14.
In aerobic organisms, the free radicals are constantly being produced during the normal cellular metabolism. The antioxidant properties of many organisms and particularly of wild mushrooms with their content in antioxidant compounds such as tocopherols, can detoxify potentially damaging forms of activated oxygen. Herein, a comparative study of tocopherols composition and antioxidant properties of in vivo (fruiting bodies) and in vitro (mycelia) ectomycorrhizal fungi: Paxillus involutus and Pisolithus arhizus. Tocopherols were determined by high performance liquid chromatography (HPLC) coupled to a fluorescence detector. The antioxidant properties were studied in terms of DPPH radical-scavenging activity, reducing power and inhibition of β-carotene bleaching. Fruiting bodies revealed the highest antioxidant properties, including scavenging effects on free radicals (EC50 = 0.61 and 0.56 mg/ml) and inhibition of lipid peroxidation capacity (EC50 = 0.40 and 0.24 mg/ml for P. involutus and P. arhizus, respectively), than mycelia produced in vitro cultures. Nevertheless, mycelia revealed higher levels of total tocopherols than fruiting bodies, and particularly P. arhizus mycelium proved to be a powerful source of γ-tocopherol (154.39 μg/g dry weight). 相似文献
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17.
Arun Bhardwaj Suman Kapila Shilpa Vij 《International journal of food microbiology》2010,141(3):156-170
In the present investigation, a previously isolated Enterococcus faecium KH 24 strain was evaluated for the presence of virulence determinants (agg, esp, efaAfm, gelE, cylA, cylB, clyM, cpd, cob, ccf, ace and hyl), sensitivity to various antibiotics and production of biogenic amines. No virulence determinants were detected, except efaAfm. KH 24 was found to be sensitive to most of the tested antibiotics and none of the biogenic amines were produced by it. Moreover, KH 24 showed good in vitro tolerance to biological barriers and furthermore, its survival in gut of mice was also evaluated. Mice group fed with E. faecium KH 24 strain showed better weight gain and nearly 1 log cfu/g decrease in Salmonella enteritidis counts in the intestines as compared to control (p < 0.05). Enhanced growth of lactobacilli (p < 0.05) and decrease in coliform counts (p < 0.05) were also observed in test group. E. faecium KH 24 is, therefore, found to be a safe strain and it may be used as protective culture or as a probiotic in food preparations. 相似文献
18.
Sung-Yong Yang Chung-oui Hong Hojoung Lee Sang-yul Park Byung-gyu Park Kwang-Won Lee 《Food chemistry》2012
Perilla frutescens leaves are often used in East Asian gourmet food. In this study, we investigated the hepatoprotective effects of P. frutescens leaves grown in different concentrations of sucrose (0, 115, 175 and 235 mM sucrose) leading to four samples of perilla leaf extracts (PLEs). Based on caffeic acid level and antioxidant activities, further experiments were conducted using perilla leaf extracts treated with 6% sucrose compared with non-treated perilla leaf extracts as a control. Oral intubation with non-treated perilla leaf extracts or perilla leaf extracts treated with 6% sucrose (1000 mg/kg b.w. rat) for 5 days was conducted before treatment with a single dose of tert-butyl hydroperoxide (0.5 mmol/kg b.w., i.p.) led to a significant reduction of hepatic toxicity in the perilla leaf extracts treated with 6% sucrose. We demonstrated that P. frutescens with higher contents of caffeic acid was produced, and that sucrose could play a role in the induction of this secondary metabolite. Sucrose-treated perilla leaves, which had better antioxidant activities than untreated leaves, can be used as a potential dietary source. 相似文献
19.
Samuel HeenanChristos Soukoulis Patrick SilcockAlessandra Fabris Eugenio ApreaLuca Cappellin Tilmann D. MärkFlavia Gasperi Franco Biasioli 《Food chemistry》2012,131(2):477-484
In the present study, PTR-TOF-MS was applied to better understand the influence of sugar composition on flavour release in a strawberry flavoured cereal bar system. To achieve this, measurements were made both statically from the headspace above cereal bar samples (in vitro) and dynamically from flavour release in the nose space during consumption (in vivo). An artificial strawberry flavour of known constituents (17 flavour active volatile compounds) was used in the preparation of cereal bars. For in vitro measurements, eight samples varying in the glucose syrup solids 42DE to polydextrose ratio were assessed. Measurements clearly showed that the level of glucose syrup solids substitution by polydextrose influenced the release of the added flavour compounds. In addition, distinguishable differences were detected for the release of volatile compounds between samples with different levels of glucose syrup solids and polydextrose during in vivo measurements. The improved mass resolution, sensitivity and speed of PTR-TOF-MS enabled direct comparisons between the rate compounds reached the nose space, maximum nose space concentration of compounds, and the time after which compounds were no longer detected in the nose-space. 相似文献
20.
Amid Mehrnoush Chin Ping Tan Mirhosseini Hamed Norashikin Ab. Aziz Tau Chuan Ling 《Food chemistry》2011
This study investigated the possible relationship between the encapsulation variables, namely serine protease content (9–50 mg/ml, X1), Arabic gum (0.2–10% (w/w), X2), maltodextrin (2–5% (w/w), X3) and calcium chloride (1.3–5.5% (w/w), X4) on the enzymatic properties of encapsulated serine protease. The study demonstrated that Arabic gum, maltodextrin and calcium chloride, as coating agents, protected serine protease from activity loss during freeze-drying. The overall optimum region resulted in a suitable freeze drying condition with a yield of 92% for the encapsulated serine protease, were obtained using 29.5 mg/ml serine protease content, 5.1% (w/w) Arabic gum, 3.5% (w/w) maltodextrin and 3.4% (w/w) calcium chloride. It was found that the interaction effect of Arabic gum and calcium chloride improved the serine protease activity, and Arabic gum was the most effective amongst the examined coating agents. Thus, Arabic gum should be considered as potential protection in freeze drying of serine protease. 相似文献