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1.
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
2.
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
3.
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
4.
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
5.
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
6.
7.
The diversity of 87 Lactobacillus paracasei and Lactobacillus plantarum/paraplantarum strains, previously identified from different autochthonous dairy products, was investigated by phenotypic and genotypic
approaches. The increased resolution obtained using phenotypic and genotypic characterization allowed the level of strain
heterogeneity detection to be widened. Phenotypic diversity was evaluated by studying biochemical characteristics of technological
interest, including antimicrobial and proteinase activities, resistance to nisin, aggregation ability, production of exopolysaccharides,
acetoin and diacetyl, citrate utilization, and antibiotic susceptibility. Genotypic diversity was generally evaluated by PCR
amplification of repetitive bacterial DNA element fingerprinting using the (GTG)5 primer [(GTG)5-PCR]. Moreover, in cases where strains were not discriminated by (GTG)5-PCR combined with phenotypic analysis, pulsed-field gel electrophoresis (PFGE) analysis was performed. The results indicate
that L. plantarum/paraplantarum and L. paracasei natural isolates from artisanal dairy products are a gold mine in terms of diversity of strains and could be potentially
interesting to dairy companies for the formulation of functional starter cultures in the production of innovative foods. 相似文献
8.
In the present study, the disinfection efficacy of slightly acidic electrolyzed water (SAEW) and strongly acidic electrolyzed water (AEW) was tested on three bacteria, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis and the disinfection mechanism was discussed. The results showed that SAEW had a stronger antibacterial efficacy against these tested bacteria in comparison with AEW. The results also showed that both SAEW and AEW treatments could damage the cell membrane, which was demonstrated microcosmically by scanning electron microscopy (SEM), thus causing leakages of protein, DNA, RNA, and ATP, resulting in the death of microbes. Moreover, AEW treatment could not cause the degradations of DNA and RNA, and nucleic acids including DNA and RNA are not the target point of its bactericidal efficacy. However, SAEW could maybe cause the degradation of RNA, and RNA may be the target in its antibacterial activity. We suggested that the differences in antibacterial efficacy between SAEW and AEW could be explained by the different impacts on RNA of tested strains. 相似文献
9.
Anna Okoń Joanna Stadnik Zbigniew Józef Dolatowski 《Food science and biotechnology》2017,26(3):633-641
The effect of the potentially probiotic bacteria strain of Lactobacillus acidophilus Bauer and probiotic bacteria Bifidobacterium animalis ssp. lactis BB12 on proteolytic changes of proteins in dry-cured loins during fermentation and cold storage was studied. Results of the conducted tests demonstrated that the use of probiotic bacteria for the production of dry-cured meats impacts the generation of products of protein proteolysis with high antioxidant activity. The highest antioxidant activity of peptides after fermentation and cold storage was observed in the loin with the strain B. animalis ssp. lactis BB12 and the loin with the mixture of strains L. acidophilus Bauer and B. animalis ssp. lactis BB12. Qualitative analysis of peptides demonstrated that peptides with weight below 3.5 kDa are characterized by the highest capacity of quenching the ABTS cation radical, including the peptides in loins with the strain B. animalis ssp. lactis BB12. 相似文献
10.
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
11.
Gabriel Bonetto Bampi Geciane Toniazzo Backes Rogério Luis Cansian Fernando Eustáquio de MatosJr. Isabella Maria Araldi Ansolin Bianca Carla Poleto Larissa Rossett Corezzolla Carmem Sílvia Favaro-Trindade 《Food and Bioprocess Technology》2016,9(8):1422-1428
The use of probiotic microorganisms has been limited by the difficulty of maintaining their viability during processing and throughout the product’s shelf life. This study evaluated the viability of microencapsulating Lactobacillus acidophilus (LA) and Bifidobacterium animalis subsp. lactis (BL) using the spray chilling technique to add them to savory cereal bars. The results showed that spray chilling generated a powder that was composed of smooth and continuous spheres with low moisture content and low water activity. The microencapsulated microorganisms exhibited a storage viability at least of 90 days as microparticles and in savory cereal bars, and their counts were superior to those resulting from other methods of adding activated and lyophilized probiotics to savory cereal bars. Thus, microparticles prepared by spray chilling are good vehicles for incorporating probiotics into cereal bars and have the potential to release the probiotics in the consumers’ intestines by means of fat digestion. Savory cereal bars that did and did not contain probiotics exhibited no differences in sensorial acceptance or commercial potential. 相似文献
12.
Ji-Eun Kang Chan-Woo Kim Soo-Hwan Yeo Seok-Tae Jeong Yong-Suk Kim Han-Seok Choi 《Food science and biotechnology》2018,27(3):715-724
Long-term aging of Yakju, a traditional Korean liquor made of rice and Nuruk (a fermentation agent), causes browning and odor and flavor development. This study investigated the effects of heat-treated Nuruk (50–80 °C, 30 min) on Yakju quality. The saccharogenic powers and glucoamylase, α-amylase, and carboxypeptidase activities were similar in non-heat-treated Nuruk and that treated at 50 °C. However, acidic protease and alcohol dehydrogenase decreased above 50 °C. The content of nitrogen-containing compounds was inversely proportional to the heat-treatment temperature. Compounds that cause off-flavors decreased at 50–60 °C, but increased at 70–80 °C, whereas compounds that provide fragrance increased at 50–60 °C. Sensory evaluation indicated that bad taste attributes were higher in Yakju produced using non-heat-treated Nuruk. Therefore, heat treatment of Nuruk at 50 °C can be adopted as a method for improving Yakju quality, as enzymatic activities that affect color, aroma, and taste are regulated. 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.
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
15.
Mi Jang Jin-Woo Min Dong-Uk Yang Seok-Kyu Jung Se-Young Kim Deok-Chun Yang 《Food science and biotechnology》2011,20(1):131-135
The pH of red ginseng extracts fermented with Saccharomyces cerevisiae and Saccharomyces carlsbergensis decreased rapidly during 3 days of fermentation, with no further significant change thereafter. After 20 days of fermentation,
a relatively small difference remained in the acidity of extracts fermented with S. cerevisiae (0.54%) and S. carlsbergensis (0.58%). Reducing sugar in the S. cerevisiae and S. carlsbergensis extracts decreased from 258.6 to 45.4 and 43.2 mg/mL glucose equivalents, respectively; and ethanol contents increased from
1.5% at day 0 to 16.0 and 15.0%, respectively, at day 20. Ginsenosides Rb1, Rb2, Rc, Re, Rf, and Rg1 decreased during the fermentation with S. cerevisiae, but Rd and Rg3 increased by day 12. Ginsenosides Rb1, Rb2, Rc, Re, and Rg1 decreased gradually in the extract with S. carlsbergensis, but Rd and Rg3 were increased at day 6 and 9, respectively. 相似文献
16.
Jung-Beom Kim Yong-Bae Park Suk-Ho Kang Myung-Jin Lee Ki-Cheol Kim Hong-Rae Jeong Dae-Hwan Kim Mi-Hye Yoon Jong-Bok Lee Deog-Hwan Oh 《Food science and biotechnology》2011,20(4):941-948
The prevalence, genetic diversity, and antibiotic susceptibility of Cronobacter species (Enterobacter sakazakii) isolated from sunshik products, its ingredients, and root vegetable farm’s soils were investigated to analyze main reservoirs and contaminated
sources of Cronobacter spp. Cronobacter spp. was isolated from 9 of 15 sunshik products, 26 of 72 its ingredients, and 2 of 39 soils. The root vegetables such as sweet potato and carrot showed higher
contamination rate (70%) than the other sunshik ingredients. All isolates showed 929 bp band amplified from 16S rRNA and resistant to ampicillin, amoxicillin/clavulanic
acid, and cefazolin. All isolates showed diverse random-amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis
(PFGE) band patterns. However, 3 cases of RAPD banding patterns between clinical strains and isolates from sunshik products and root vegetables (yam, carrot) were related with similarities level of 80%. These studies indicated that root
vegetables can be an important contamination source of Cronobacter spp. in sunshik products. Thus, the preparation of root vegetables for manufacturing sunshik products used as a weaning diet was handled with more care than the other sunshik ingredients. 相似文献
17.
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
18.
Jeong Jin Ahn Youngjoo Kim Ji Young Hong Gi Won Kim Seol Young Kim Seung Yong Hwang 《Food Analytical Methods》2016,9(7):2036-2041
Larimichthys polyactis (redlip yellow croaker) and Larimichthys crocea (large yellow croaker) are commercially important fish species in East Asia with high differences in their market values. In Korea, consumers prefer L. polyactis to L. crocea, although it is difficult to distinguish them based on their morphological traits. The objective of this study was to develop an assay for differentiating L. polyactis and L. crocea using fluorescence melting curve analysis (FMCA) with a single locked nucleic acid (LNA) probe. Species-specific regions of the mitochondrial 16S rDNA were selected as LNA probes. The target sequences of L. polyactis and L. crocea had a 2-bp difference, and a single LNA probe was identified using melting temperature (Tm) shift. LNA probe was 100 % complementary to the target sequence of ten L. polyactis samples, giving a significantly higher Tm value (66 °C) than that of five L. crocea samples (42 °C). Overall, the developed LNA-based FMCA system had high efficiency, multiplexity, and simplicity, and could be effectively used for differentiating L. polyactis and L. crocea, and as a food analyzing method based on DNA sequence. 相似文献
19.
Si-Hyup Kim Se-Hee Lee Soo-Hwan Yeo Sang-Hyeon Lee Chul Cheong 《Food science and biotechnology》2017,26(4):959-967
The objective of this study was to select and identify yeasts and molds isolated from traditional nuruk and to investigate their brewing characteristics for Cheongju production. The yeast strains Y190 (Accession ID-KACC 93251P), Y263 (Accession ID-KACC 93252P), and Y270 (Accession ID-KACC 93253P) showing high alcohol and flavor productivity were isolated and identified by phylogenetic inference based on an internal transcribed spacer 2 region sequence analysis. In addition, Aspergillus oryzae 83-10 (Accession ID-KACC 93254P) showing the highest enzyme activity was isolated. This study provides basic data for the production of Korean Cheongju and assesses the applicability of these three yeast strains and A. oryzae 83-10 isolated from traditional nuruk. 相似文献
20.
The histidine decarboxylating activity and production of biogenic amines by Morganella morganii (NCIMB, 10466), Klebsiella pneumoniae (NCIMB, 673) and Hafnia alvei (NCIMB, 11999) were investigated using a rapid HPLC method. Derivatisation of the bacterial samples was carried out using benzoyl chloride. A gradient elution system was used for analysis with a mixture of acetonitrile and HPLC grade water. Bacterial strains not only produce histamine in histidine-enriched broth but also the other biogenic amines. The chromatographic results show that bacterial strains are also capable of producing spermine and spermidine in histidine-enriched broth. Bacterial ammonia production by all three strains was clearly detected since ammonia is generated during the degradation of histidine. The study demonstrates that the highest histamine production was obtained by Morganella morganii, followed by Klebsiella pneumoniae, and the lowest with the Hafnia alvei. Therefore, Morganella morganii and Klebsiella pneumoniae have strong histidine decarboxylase activity since they are prolific histamine-forming bacteria 相似文献