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1.
The various extracts from chamdanggui (Angelica gigas Nakai) and sogdan (Phlomis umbrosa Turcz) were evaluated for estrogenic activity and characterized according to HPLC profile. Chamdanggui and sogdan were individually extracted with 4 solvents (hot water, 70% ethanol, n-butanol, and dichloromethane) of differing polarities. Estrogenic activity was determined by E-screen using an estrogen-dependent
MCF-7 BUS cell. Although almost all extracts showed estrogenic effects in a concentrationdependent manner, the hot water extract
from chamdanggui (250 μg/mL) had the higher effect (138%). Among 90 fractions using HPLC separation of the hot water extract from chamdanggui, fraction 21 and 28 produced the highest estrogenic effects of 178 and 163% at 10 μg/mL, respectively. The results imply
that the hot water extract from chamdanggui could be useful as an alternative hormone replacement therapy. 相似文献
2.
3.
A. Murat Gizir Nuzhet Turker Erdem Artuvan 《European Food Research and Technology》2008,226(3):363-370
The anthocyanins present in black carrot were extracted with pressurized water acidified with sulfuric, citric and lactic
acids. Anthocyanin degradation became significant above 100 °C and there was no improvement when extraction pressure was increased
to 100 bar. Therefore, the extraction from black carrot was carried out at temperatures 50, 75 and 100 °C under 50 bar pressure.
The extraction efficiencies in terms of acylated and non-acylated anthocyanins were comparable for all three acids used to
acidify water at 50 °C, while similar results were observed at 75 °C for both citric and lactic acids. Water acidified with
lactic acid showed significantly higher extraction efficiency at 100 °C compared to water acidified with sulfuric and citric
acids. Highest degree of polymerization together with increasing degree of browning was observed within extracts when sulfuric
acid was used. On the other hand, when organic acids were used to acidify water, a higher extraction efficiency of anthocyanins,
accompanied with a relatively low polymerization and browning was observed, with lactic acid giving the best results. 相似文献
4.
A real-time polymerase chain reaction (PCR) method for Salmonella ssp. detection in food samples has been developed and validated in-house. The specificity of the assay was confirmed by tests with 295 different
Salmonella strains, including four strains of Salmonella bongori. When tested with extracted Salmonella DNA the lowest detected amount was found to be 5 fg, which is equivalent to approximately one genome copy. The detection limit was further determined by artificial contamination of minced meat with S. Typhimurium cells and of pastry with S. enteritidis using the most probable number approach for cell dose dilutions. It was calculated that even one colony forming unit of Salmonella was still detectable in 25 g food after enrichment culture for 18 h. An additional PCR system for internal positive control, which was included in each reaction and detected in parallel via another reporter fluorescence dye, has no negative impact on the sensitivity of the assay. The method was evaluated with 1,293 naturally contaminated food samples and compared to the conventional cultural method. Of 55 positive PCR samples, 45 were confirmed by the cultural method. The statistical comparison revealed a correlation of 99.2% for specificity, of 100% for sensitivity and of 99.2% for trueness. The results of the comparative analysis and the advantages of the real-time PCR method for detection of Salmonella ssp. under routine laboratory conditions are discussed. 相似文献
5.
Martina Blažková Marjo Koets Pavel Rauch Aart van Amerongen 《European Food Research and Technology》2009,229(6):867-874
We present a new nucleic acid lateral flow immunoassay (NALFIA) for the assessment of listeria contamination. The detection
procedure starts with enrichment of sample in Half Fraser broth (24 h). Following isolation of DNA, a duplex PCR is performed
with two labelled primer sets, one generic and directed to a specific sequence of the gene encoding 16S rRNA from Listeria spp. and the other specific and directed to a part of the prfA gene encoding the central virulence gene regulator from the food pathogen Listeria
monocytogenes (3.5 h). The PCR solution is directly added to the one-step assay device and the appearance of a grey/black line is indicative
of the presence of specific amplicons (max 15 min). In all tests performed, the method correctly identified L.
monocytogenes and strains of Listeria spp. PCR material of over 20 food samples was tested by NALFIA. The method proved to be useful for the detection of L.
monocytogenes in different kinds of food samples. 相似文献
6.
Leona Buňková František Buňka Michaela Hlobilová Zuzana Vaňátková Dana Nováková Vladimír Dráb 《European Food Research and Technology》2009,229(3):533-538
The aim of this paper was to study the biogenic amines (histamine, tyramine, putrescine, cadaverine, agmatine, spermine and
spermidine) production of selected technological important lactic acid bacteria (strains of the genera Lactococcus, Lactobacillus and Streptococcus). Three methods (ion-exchange chromatography (IEC), PCR and cultivation method with pH indicator) were used. Within the 39
strains of lactic acid bacteria tested, the production of tyramine (formed by tyrosine decarboxylase) was detected in eight
strains (3 strains of Lactococcus lactis subsp. lactis, three strains of Lactococcus lactis subsp. cremoris, 1 strain of Streptococcus thermophilus and 1 strain of Lactobacillus delbrueckii subsp. bulgaricus). The other tested biogenic amines were not detected. Cultivation in decarboxylation broth seems to be the least accurate
method for the detection of biogenic amines due to enhanced risk of false-positive reactions. Therefore, in order to detect
bacteria producing biogenic amines, the combination of PCR and chromatographic methods (e.g. IEC) can be recommended. 相似文献
7.
Xavier Bonjoch Laia Calvó Marçal Soler Olaya Ruiz-Rueda L. Jesús Garcia-Gil 《Food Analytical Methods》2010,3(1):40-46
A new rapid method based on real-time PCR was developed to detect four thermophilic Campylobacter species (Campylobacter jejuni, Campylobacter coli, Campylobacter lari, and Campylobacter upsaliensis) in food samples. The assay targeted the bipA gene for C. upsaliensis and C. lari, whereas the gene encoding the ATP-binding protein CJE0832 was used to detect C. coli and C. jejuni. These genes were chosen for this assay due to their low variability and mutation rate at a species level. The multiplex
PCR showed 100% inclusivity for all 25 thermophilic Campylobacter strains tested and 100% exclusivity for 38 non-targeted strains belonging to closely related species. The newly developed
real-time PCR could detect down to 102 genomes/reaction and displayed efficiency above 97% for all species except for C. upsaliensis (90.1%). The method proved to be a reliable tool for food analysis, showing 100% sensitivity, 96% efficiency, and 92.45%
specificity when validated against the gold standard method UNE-EN ISO 10272:2006 using 200 diverse food samples (meat, fish,
fruits and vegetables, and raw milk). In artificially spiked samples, the detection limit of the method was 10 cfu/g in salad,
5 cfu/g in turkey meat, and 1 cfu/g in the rest of meat samples tested. Consequently, the newly designed molecular tool represents
a quick and safe alternative to obtain reliable results concerning the presence/absence of the main thermophilic Campylobacter in any food sample. 相似文献
8.
Thermal inactivation of quality-related enzymes in both cauliflower crude enzyme extracts and fresh tissue samples was studied
in temperature range 50–100 °C. For crude enzyme extracts, several parameters, reaction rate constants (k) and activation energy (E
a) as well as decimal reduction time (D) and (z) values, were used to characterize the thermal stability. The rates of inactivation were found to follow first-order inactivation
kinetics. Activation energies varied between 101.18 and 208.42 kJ mol−1 with z values of 10.59–24.09 °C. The examined kinetics indicated that lipoxygenase was the most heat resistant followed by peroxidase,
polyphenol oxidase, pectin methyl esterase and ascorbic acid oxidase. Furthermore, the obtained results from the blanched
fresh tissues indicated that inactivation of lipoxygenase secured disappearing of any other enzyme activities. Therefore,
this study recommends using lipoxygenase as an indicator enzyme to optimize the thermal treatments of cauliflower products. 相似文献
9.
Sun Kyoung Yoon Kashif Ghafoor Yun Sook Kang Mun Gi Sohn In-Gyun Hwang Ki Sung Kwon Jiyong Park 《Food science and biotechnology》2011,20(1):23-28
The exposure assessment was carried out for Staphylococcus aureus in kimbab by predicting growth of S. aureus and the production of enterotoxin using Food MicroModel® program. Environmental parameters selected were pH 5.5, Aw 0.999, and storage temperatures in the range of 10 to 30°C. It was predicted that 6.3 hr could be a critical time for enterotoxin production while kimbab was stored at 30°C. Mild case scenario analysis showed that enterotoxin could not be produced if kimbab was kept at 10°C during preparation and distribution and then left at 25°C for 4 hr before consumption. In the worst case scenario, the keeping time at 25°C was assumed to be 7.0 hr. The level of S. aureus in the worst case was predicted to be 6.8×106 CFU/g which is lower than the critical level (7.8×106 CFU/g) for toxin production. 相似文献
10.
A novel real-time polymerase chain reaction (PCR) method for the detection of hazelnuts in food 总被引:1,自引:0,他引:1
A real-time PCR (polymerase chain reaction)-based method for the detection of hazelnuts (nuts of Corylus avellana or C. maxima) in confectionery and bakery products is described. The method consists of DNA isolation by chaotropic solid phase extraction
and the subsequent PCR with hazelnut-specific primers and a TaqMan fluorescent probe. The primers and the probe are targeted
to the hsp1 gene encoding for a low molecular weight heat-shock protein. The method was positive for five hazelnut varieties approved
in Slovakia and negative for all other tested plant materials used in food industry including peanuts, walnuts, almonds, pistachio
nuts, cashews and chestnuts. The intrinsic detection limit of the method was 13 pg hazelnut DNA, which corresponds to approximately
27 genome equivalents (1C). Using a series of model pastry samples with defined hazelnut contents, a practical detection limit
of 0.01% (w/w) hazelnut was determined. Practical applicability of the PCR method was tested by the analysis of 20 food samples
(confectionery and bakery products) along with ELISA. For all of the food samples, identical results were obtained by both
methods, which conformed to the labelling. The presented PCR method is useful for sensitive and selective detection of hazelnuts
in food samples and can be performed in one working day. 相似文献
11.
Frederic Debode Kamila Zdeňková Eric Janssen Anette Tizolova Patrick du Jardin Gilbert Berben Kateřina Demnerova 《Food Analytical Methods》2018,11(8):2172-2180
Two singleplex TaqMan methods were developed for the detection of potato targets: one for the detection of the tpinII terminator, which is an emerging terminator used in GM constructs, and one for the detection of the endogenous StLS gene of potato. Performance criteria such as specificity and sensitivity were successfully tested for the two methods, taking into account the recommendations of international guidelines. The presence of the StLS target was checked in 16 potato cultivars. The StLS target is present at low copy number and can be used for quantitation purposes, as demonstrated on transgenic potatoes in this paper. The StLS target is an excellent candidate to replace the presently recommended endogenous target based on the UGP gene, which shows several disadvantages due to its high copy number and lack of specificity. The research also indicates that DNA can easily be extracted from different parts of potato tubers with a classical cetyltrimethylammonium bromide method. 相似文献
12.
The heavy metal contents and chemical compositions among mackerel species were investigated. Atlantic and chub mackerel had
higher mercury, but lower lead than blue mackerel. Chub mackerel had the highest crude fat (18.62%) and the lowest moisture
(58.29%), whereas blue mackerel had the highest moisture (70.10%) and the lowest crude fat (2.89%). Atlantic and blue mackerel
had total saturated fatty acids (SFA)>polyunsaturated fatty acids (PUFA)>monounsaturated fatty acids (MUFA), whereas chub
mackerel had PUFA>SFA>MUFA. The main SFA of the 3 mackerels were 16:0 and the main PUFAs were 22:6n-3 and 20:5n-3. The total
amino acid contents in Atlantic, blue, and chub mackerel were 190.63, 169.49, and 172.97 mg/g, respectively. The major amino
acids of the 3 mackerels were glutamic acid, aspartic acid, lysine, and leucine. 相似文献
13.
Isotherms of shiitake mushroom (Lentinus edodes) at 25 and 40°C were determined and drying kinetics of whole and sliced shiitake mushrooms were tested using a convective air drying method at different drying temperature of 40, 50, 60, and 70°C. The monolayer
moisture contents of the mushroom were 7.23 and 5.44 g water/100 g of dry solids at 25 and 40°C, respectively. Both mushroom
samples showed falling drying rate periods with increasing drying rates with increases in drying temperature, and the drying
rate of the sliced mushrooms was faster than that of the whole mushrooms at the same drying conditions. The kinetic parameters
for dehydration of the mushrooms were determined using the Newton model and the Classical diffusion model. Activation energy
(E
a
) values as determined using the Newton model were 22.58 and 20.48 kJ/mol for the whole and sliced mushrooms, respectively. 相似文献
14.
A real-time polymerase chain reaction (PCR)-based method for the detection of the walnut (Juglans regia) component in food is described here. The method consists of DNA isolation by chaotropic solid phase extraction and the subsequent PCR with walnut-specific primers and a TaqMan fluorescent probe. The primers and the probe are targeted to the jug r2, a major allergen gene of walnut. The method was positive for 8 varieties of walnut and negative for all other tested plant materials used in food industry, including pecan nuts. The intrinsic detection limit of the method was 0.24 ng walnut DNA. Using a series of model pastry samples with defined walnut contents, a practical detection limit of 0.01% walnut content was estimated. Practical applicability of the PCR method was tested by the analysis of 13 food samples (bakery and confectionery products), out of which two cakes were found to contain walnuts although they were not adequately labelled. The presented PCR method is useful for sensitive and selective detection of walnuts in food samples and can be performed in one working day. 相似文献
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16.
‘Lemon Myrtle’ is becoming increasingly popular in Europe both for use in cuisine and phytotherapy. However, this common name
covers two completely different species, Backhousia citriodora F. Muell. and Leptospermum citratum Challinor, Cheel & A.R.Penfold. These species differ with respect to secondary compounds and even can cause, if mixed up
and applied in high dose, toxic effects. We describe how the two species can be discriminated microscopically making use of
differences in the morphology of leaf pavement cells and the relative size of palisade parenchyma. Based on the large subunit
of ribulose-1,5-bisphosphate carboxylase oxygenase (rbcL) as molecular marker, the phylogenetic position of the two species
within the Myrtaceae could be clarified. This sequence information was used to develop a simple assay to discriminate the
two species even in dried and highly fragmented mixtures as typically occurring in commercial samples. This assay utilises
the occurrence of single-nucleotide exchanges between those species that produce different fragments when the rbcL amplificates
are restricted with Sac II. 相似文献
17.
Juan Liu Bing Gu Jun Bian Shuigen Hu Xi Cheng Qiangkun Ke Huifang Yan 《European Food Research and Technology》2008,227(3):919-924
To acquire the effectiveness of oral treatments, aqueous extracts of Anodonta woodiana (HB) were incorporated into liposome and its antitumor activities evaluated in vivo. The HB-loaded liposomes (HBL) were prepared
at a mean size of 14.85 μm by reverse-phase evaporation method. Referring to the maximum tolerated doses test, mice with orally
administrated HBL, at a 3 g/kg body weight dosage, showed no obvious acute toxic sign. Furthermore, the tumoricidal activities
of HBL against C26 murine colon carcinoma, Lewis lung tumor, human QGY hepatic carcinoma and MKN-45 gastric tumor were examined,
respectively. In contrast to free HB, HBL possessed remarkable antitumor activity. Simultaneously, the effect of HBL was observed
in a dose-dependent manner. For C26 murine colon carcinoma and Lewis lung tumor, the inhibitory ratios of HBL were 54.36 and
51.97% at a dose of 400 mg/kg, respectively. The suppression of tumor growth and the reduction in body weight were more pronounced
in human QGY hepatic carcinoma and MKN-45 gastric tumors inoculated mice by treatment of HBL during 30 days. All these promising
results implied that liposome-incorporated aqueous extracts of Anodonta woodiana had a more potential application as a natural antitumor and immunomodulator formulation. 相似文献
18.
Henner Neuhaus Matthias Denker Dirk Holthuis Frerk Feldhusen Edda Bartelt 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2016,11(4):311-316
We investigated the composition of muscle tissue from 30 untreated striped catfish (Pangasianodon hypophthalmus) and 40 untreated pikeperch (Sander lucioperca). The analyzed fillets had a mean moisture level of 77.5 % in striped catfish and 78.7 % in pikeperch. The mean level of protein content was 19 % in striped catfish and 20.5 % in pikeperch; the pH was 6.5 in striped catfish and 6.8 in pikeperch. Our data provide a first basis on a legal opinion concerning fishery products that are suspected to contain high amounts of added water. These data can also be used for the calculation of added water regarding the regulation of the European Union (EU) No 1169/2011, provision of food information to consumers. 相似文献
19.
Krishnamoorthy Elavarasan Bangalore Aswathnarayan Shamasundar 《Food science and biotechnology》2017,26(5):1169-1176
Fish protein hydrolysates (FPHs) were prepared from freshwater carps (Catla catla, Labeo rohita, and Cirrhinus mrigala) using flavorzyme at different degrees of hydrolysis (DHs) ranging from 5 to 20%. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical-scavenging activity of the FPHs prepared from the three species were in the range of 50–82%; the ferric reducing power of the FPHs prepared from catla was the highest. The linoleic acid peroxidation inhibition activity of the prepared FPHs varied from 71 to 91%. The emulsion activity index of the FPHs prepared from catla and rohu decreased significantly with an increase in the DH (p < 0.05). The emulsion stability index of the FPHs prepared from the three species was the highest at 20% DH. FPHs prepared from freshwater carps possess good antioxidant and surface-active properties and are therefore suitable to be used as natural antioxidants in health-food formulation and as water-soluble antioxidants in the food-processing industry. 相似文献
20.
Samee Haider Zhenxing Li Hong Lin Khalid Jamil Bang Ping Wang 《European Food Research and Technology》2009,229(3):435-441
Food allergy has becoming the serious threat in the world for which the search of an effective anti-allergic drug is the demand
of time. Keeping in view of the potentiality of seaweeds, the ethanol extracts from Sargassum tenerrimum (ST), Sargassum cervicorne (SC), and Sargassum graminifolium turn (SG) have been studied in vivo for its antiallergenicity through passive cutaneous anaphylaxis (PCA) and active cutaneous
anaphylaxis (ACA) in female BALB/c mice. Intraperitoneal administration of these ethanol extracts inhibit mouse PCA and ACA
in a dose-dependent manner using ovalbumin (OVA) and shrimp allergen as triggering agents to induce allergenicity over mice.
The extract of ST containing phlorotannin has been found most active over the suppression of PCA triggered by OVA and shrimp
with IC50 values of 25.64 and 40.98 mg/kg, respectively and an efficacy comparable to that of an anti-allergic drug disodiumcromoglycate.
Similarly, ST inhibits ACA triggered by ova and shrimp allergen in the mouse, with 50% suppression at 25.5 and 43.53 mg/kg,
respectively. The results presented here show that these extracts are active on the studied models among which ethanol extract
of ST was the most potent, leading toward the promising development of a new class of anti-allergic drugs. 相似文献