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1.
The influence of different treatments, i.e., crushing, high temperature short time (90 °C/4 min) (HTST) and low temperature long time (60 °C/40 min) (LTLT) blanching, acidification (pH 4.3), and sequences of these treatments on the folate poly-γ-glutamate profile and stability were investigated. In this study, broccoli was used as a case study. Regarding the folate poly-γ-glutamate profile, endogenous folate poly-γ-glutamates in broccoli florets were found predominantly as hepta- and hexa-γ-glutamates. Crushing raw broccoli, acidification and LTLT blanching enhanced folate deconjugation resulting in monoglutamate, di- and tri-γ-glutamates. Compared to other treatments, HTST blanching preformed prior to crushing resulted in the highest concentration of long chain poly-γ-glutamates. Regarding folate poly-γ-glutamates stability, acidification combined with LTLT blanching decreased folate stability whereas HTST blanching combined with different sequences of blanching and crushing did not affect folate poly-γ-glutamates stability. It was concluded that crushing (prior to heating), acidification and blanching could be strategically applied to increase the folate monoglutamate content of broccoli.  相似文献   

2.
The objective of this study was to investigate the effects of bovine GH1, CAPN1 and CAST gene polymorphisms on carcass and meat traits in Nellore and Nellore x Bos taurus beef cattle. Three hundred animals were genotyped for GH1/MspI (TC/G in intron 3), CAPN316 (AF_252504.2:g.5709C > G) and CAST/RsaI (AY_008267.1:g282C > G) and phenotyped for rib eye area, backfat thickness, intramuscular fat, shear force (SF), and myofibrillar fragmentation index (MFI). No significant associations were observed between the GH1/MspI and CAST/RsaI polymorphisms and phenotypes, although the relation between the CAST/RsaI genotypes and meat tenderness evaluated by MFI approached significant. The fact that the CAPN316 polymorphism did not show adequate segregation in Nellore cattle confirms the difficulty of using this marker in breeding programs of different Bos indicus breeds. However, the positive results of the association analysis obtained for Nellore x B. taurus crosses contributed to the validation of previous findings.  相似文献   

3.
Cymbopogon schoenanthus L. Spreng, is an aromatic herb consumed in salads and used to prepare traditional meat recipes in Tunisia. The chemical composition, antioxidant activities and acetylcholinesterase inhibitory properties of the essential oils from fresh leaves, dried leaves and roots collected from three different locations in southern Tunisia, were evaluated. Essential oils were analysed by GC–mass spectrometry and 13C NMR. The major components were limonene (10.5–27.3%), β-phellandrene (8.2–16.3%), δ-terpinene (4.3–21.2%) and α-terpineol (6.8–11.0%). Antioxidant activity was measured by DPPH assay. The results ranged from 36.0% to 73.8% (2 μl of essential oil per mL of test solution).  相似文献   

4.
This study aims at relating the survival at 4 °C for 28 days in organic and conventional fermented milks of three strains of Bifidobacterium animalis subsp. lactis (BB12, B94 and BL04), in co-culture with Streptococcus thermophilus TA040 and Lactobacillus bulgaricus LB340, to milk fatty acids profile. Cultivability after 28 days of cold storage was improved in organic fermented milks as compared to conventional products, with slight differences among strains. In addition, the poly-unsaturated fatty acids fraction was higher in organic products, as well as the relative trans-vaccenic (TVA) and α-linolenic (ALA) fatty acids contents that were respectively 1.7 and 2.4 times higher in organic than in conventional fermented milks. From these results, it was concluded that elevated levels of TVA and ALA, together with a lower ratio between linoleic acid and α-linolenic acid, as found in organic products, improved the survival of the bifidobacteria during chilled storage.  相似文献   

5.
A total of 1120 Salmonella spp. isolates, recovered from poultry, swine and food products of animal origin (bovine, swine and poultry) over the period of 2009–2011, were investigated in order to determine their serotype, susceptibility to a panel of eleven antimicrobials (A, ampicillin; Ct, cefotaxime; Cp, ciprofloxacin; Tm, trimethoprim; Su, sulfamethoxazole; C, chloramphenicol; S, streptomycin; G, gentamicin; T, tetracycline; NA, nalidixic acid; Fl, florfenicol), and the presence of resistance determinants of extended-spectrum cephalosporins. Overall, Salmonella Enteritidis was the most common serotype in all three animal species. In 618 isolates of poultry, 32.8% comprised S. Enteritidis, 18.3% Salmonella Havana and 16.5% Salmonella Mbandaka; in 101 isolates of pigs, 21.8% comprised Salmonella Rissen and Salmonella Typhimurium, 10.9% Salmonella Derby and Salmonella London. Salmonella I 4,[5],12:i:- was the most common serotype recovered from pork and beef food products comprising 32.6% and 30% of isolates respectively, followed by S. Rissen (26% and 24%) and S. Typhimurium (18.2% and 19%), respectively. In poultry products, S. Enteritidis was the most frequent serotype (62.7%), followed by S. Mbandaka (10.2%) and S. Derby (8.5%). Susceptibility profiles differed according to the origin of the isolates. Five multidrug resistant isolates (0.45%) were further characterized as extended-spectrum β-lactamase (ESBL) producers. Polymerase chain reaction and sequencing of the amplicons confirmed the presence of blaCTX-M-1 (n = 2), blaCTX-M-14 (n = 1), blaCTX-M-15 (n = 1) and blaCTX-M-32 (n = 1); blaSHV-12 and blaTEM-1 genes were also detected in two isolates of S. I 4,[5],12:i:-. Four isolates, two S. Havana and two S. I 4,[5],12:i:-, carried class 1 integrons and in three, two S. I 4,[5],12:i:- and one S. Havana, ISEcp1 was identified associated to blaCTX-M-1, blaCTX-M-32 and blaCTX-M-14 genes. Additionally, in one S. I 4,[5],12:i:- isolate, orf477 was identified linked to blaCTX-M-32. No plasmid mediated quinolone resistance-encoding genes were detected. Here, we report for the first time the presence of blaCTX-M genes in Salmonella enterica subsp enterica isolates recovered from poultry and food products of swine origin, in Portugal.  相似文献   

6.
Antioxidant activity, neuroprotective effect and acetylcholinesterase inhibitor activity were studied in acetylated flavones from Galeopsis ladanum L. (Lamiaceae), previously isolated and identified by UV-spectra, UPLC–MS/MS and 1H-NMR spectroscopy. Structure–activity relationships of flavonoids have been determined in many antioxidant assays, generally focused on hydroxyl groups. In this study we have detected new interesting structure–activity relationships for the isolated flavonoids due to the acetylation of sugar moiety of these flavonoids. Methylation at 4′-OH and monoacetylation is beneficial to inhibiting AChE and shows a neouroprotective effect.  相似文献   

7.
Guaiacol is a profoundly negative taint/off-flavour produced by the increasingly common microbial contamination of fruit juices with Alicyclobacillus spp. The objectives of this study included: determining sensory thresholds for guaiacol in orange juice (OJ), developing an analytical method whose detection limits were equivalent to sensory thresholds and determining levels of Alicyclobacillus spp. that would produce detectable levels of guaiacol. A 12 member trained panel was used to establish guaiacol detection and recognition thresholds. Guaiacol ortho and retro nasal detection thresholds in OJ were 0.70 and 0.53 μg/l respectively. Odour recognition threshold was 2.0 μg/l. A SPME GC–MS Selected Ion Monitoring (SIM) procedure was optimised to achieve analytical detection limits of 0.5 μg/l. Optimum guaiacol detection limit was achieved using only responses from m/z 109 and 124. Ion ratios (m/z 109/124) and linear retention index value matching were used to confirm the identification of guaiacol. Quantification was achieved using peak areas from standard guaiacol additions in orange juice between 0.5 and 100 μg/l. Alicyclobacillus growth of 2.2 log CFU/ml in OJ produced just detectable levels (0.7 μg/l) of guaiacol.  相似文献   

8.
9.
The antioxidant potential of 1,2,3,4,6-penta-O-galloyl-β-d-glucose (PGG), isolated from Elaeocarpus sylvestris var. ellipticus, was investigated by various established systems based on cell-free and cell system experiments, such as radical detection, antioxidant enzyme assay, lipid peroxidation detection, and cell viability assay. PGG was found to quench the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species. PGG recovered the cellular antioxidant enzyme activities of superoxide dismutase, catalase, and glutathione peroxidase, which were reduced by H2O2 treatment, thereby resulting in the inhibition of lipid peroxidation. Cytoprotective effects of PGG were based on the results of DNA fragmentation, mitochondrial membrane potential (Δψ), apoptotic body formation, and caspase-3 activity. The results suggest that PGG protects cells against H2O2-induced cell damage via antioxidant properties.  相似文献   

10.
We have evaluated the herb–drug interaction potential of Ssang-hwa-tang (SHT) mediated by cytochrome P450 (CYP) inhibition/induction. Further, the effects of fermentation on the CYP-mediated herb–drug interaction potential were determined. SHT showed inhibitory activity toward CYP1A2, but not 2A6, 2B6, 2C9, 2C19, 2D6, 2E1, and 3A4 in human liver microsomes. The results of the enzyme kinetic study suggested that the SHT-induced CYP1A2 inhibition is mixed reversible inhibition. The hepatic CYP expression and activity in rats treated with SHT were examined. The expression/activity of CYP2E1 increased as a result of SHT extract treatment (P < 0.005 or P < 0.001, respectively), which raises the possibility that SHT may increase the toxicity of environmental toxicants through the elevation of CYP2E1-mediated metabolic activation. SHT fermentation using Lactobacillus fermentum or Lactobacillus gasseri resulted in attenuation of the SHT-induced CYP1A2 inhibition, but not CYP2E1 induction, suggesting that changes in the chemical composition of SHT through fermentation can affect the inhibition of CYP1A2 activity.  相似文献   

11.
12.
13.
Healthy fruits of Capsicum annuum L. cv. Chelsea (yellow bell pepper) and one infected by Colletotrichum gloeosporioides were analysed for polyphenols via high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC–MS/MS). Among seven polyphenols characterized, four components in the C. annuum fruits were identified for the first time. To investigate the characteristics of the polyphenols as defence materials, the content change of the fruit polyphenols inoculated with C. gloeosporioides was monitored by HPLC. It was observed for the first time that de novo induced N-caffeoyl putrescine (1) and caffeoyl O-hexoside (2) appeared to act as a phytoalexin in the defence mechanism of the C. annuum fruits against C. gloeosporioides, and constitutively formed feruloyl O-glucoside (3), kaempferol O-pentosyldihexoside (4) and dihydroxyflavone O-hexoside (7) as a phytoanticipin in the diseased C. annuum fruits.  相似文献   

14.

Purpose

To compare the in vitro antiparasitic effects of MGO? Manuka honey and tea tree oil against ocular Demodex.

Methods

Fifty-two viable Demodex mites were acquired from the epilated eyelashes of 9 participants with blepharitis and symptomatic dry eye. Viable mites were randomised to one of five treatment groups: cyclodextrin-complexed and uncomplexed Manuka Honey, 100% and 50% tea tree oil, and no treatment. Following treatment application, mite viability was assessed for 240?min, based on limb and body movement and/or the development of a crenated/translucent appearance. Kaplan-Meier survival analysis was then performed.

Results

The log-rank test demonstrated a significant treatment effect on the survival distribution of Demodex mites (p?<?0.001). Bonferroni-corrected post-hoc pairwise analysis showed that all treatments except for uncomplexed honey effected lower survival probabilities than the untreated group (all p?<?0.001). Among the four treatments, survival probabilities were lowest with 100% tea tree oil (all p?<?0.001), and highest with uncomplexed honey (all p?≤?0.001). No difference was observed between complexed honey and 50% tea tree oil (p?=?0.81).

Conclusions

The in vitro efficacy of cyclodextrin-complexed Manuka honey was comparable with 50% tea tree oil, an established treatment for ocular Demodex. The findings support future clinical trials investigating the therapeutic effects of complexed honey in demodectic blepharitis patients.  相似文献   

15.
Five triterpene alcohols and four 4-monomethylsterols were identified by GC–MS during the ripening of Picholine olive. The quantitative characterisation of these compounds was performed using GC–FID. The results showed that the maximum level of total triterpene alcohols (263.68 mg/100 g oil) was reached at 26th week after the flowering date (WAF) of olive; whilst the highest level of total 4-monomethylsterols (234 mg/100 g oil) was attained at 24th WAF of fruit. The percentage of these two classes represented 20–33% of total phytosterols during olive maturity. 24-Methylene cycloartenol (12–207 mg/100 g oil) and cycloartenol (27–198 mg/100 g oil) were the predominant triterpene alcohols during the ripening of Picholine olive; whereas citrostadienol (30–161 mg/100 g oil) and cycloeucalenol (11–74 mg/100 g oil) were the main 4-monomethylsterol compounds followed by obtusifoliol and gramisterol. β-Amyrin, δ-amyrin and traroxerol were less present in Picholine olive and they accounted for 14% of total triterpene alcohols at complete maturity of fruit. The level of these methylsterols was overwhelmed by the amount of 4-desmethylsterols at each stage of Picholine olive maturity.  相似文献   

16.
This study represents the first phytochemical research of phenolic components of Sercial and Tinta Negra Vitis vinifera L. The phenolic profiles of Sercial and Tinta Negra V. vinifera L. grape skins (white and red varieties, respectively) were established using high performance liquid chromatography–diode array detection–electrospray ionisation tandem mass spectrometry (HPLC–DAD–ESI-MSn), at different ripening stages (véraison and maturity). A total of 40 phenolic compounds were identified, which included 3 hydroxybenzoic acids, 8 hydroxycinnamic acids, 4 flavanols, 5 flavanones, 8 flavonols, 4 stilbenes, and 8 anthocyanins. For the white variety, in both ripening stages, hydroxycinnamic acids and flavonols were the main phenolic classes, representing about 80% of the phenolic composition. For red variety, at véraison, hydroxycinnamic acids and flavonols were also the predominant classes (71%), but at maturity, anthocyanins represented 84% of the phenolic composition. As far as we know, 10 compounds were reported for the first time in V. vinifera L. grapes, namely protocatechuic acid-glucoside, p-hydroxybenzoyl glucoside, caftaric acid vanilloyl pentoside, p-coumaric acid-erythroside, naringenin hexose derivate, eriodictyol-glucoside, taxifolin-pentoside, quercetin-glucuronide-glucoside, malylated kaempferol-glucoside, and resveratrol dimer. These novel V. vinifera L. grape components were identified based on their MSn fragmentation profile. This data represents valuable information that may be useful to oenological management and to valorise these varieties as sources of bioactive compounds.  相似文献   

17.
18.
The effect of three production systems of Iberian pigs namely Montanera (free-range system and feeding based on acorns and grass), Recebo (free-range system and nutrition based in combination of acorns, grass and mixed feeds) and Intensive (confinement with mixed feeds) on some quality traits of Longissimus dorsi (LD) and Serratus ventralis (SV) muscles were studied. Muscles from pigs raised in the Montanera system showed significantly higher CIE L, a and b values and higher haem pigment content than those from Intensive system. Similarly, muscles from pigs raised in the Montanera system had significantly higher contents of α and γ-tocopherol and phenolic compounds contents and higher lipophilic and hydrophilic activity antioxidant than those from pigs raised in the Intensive system. Fatty acids profiles from Montanera pigs had significantly higher monounsaturated (MUFA) and polyunsaturated (PUFA) fatty acids and lower saturated fatty acids (SFA) than those from pigs raised in the Intensive system. In relation to muscle effect, LD showed lower intramuscular fat (IMF), α-tocopherol, phenolic compounds, lipid oxidation and PUFA, but higher MUFA than SV.  相似文献   

19.
Hawthorn (Crataegus spp.) fruits are increasingly popular as raw materials for nutraceuticals and functional foods. As a major group of bio-active components of hawthorn, the phenolic compounds of the fruits have not been well characterized so far. After extraction with 80% aqueous ethanol, the phenolics of the fruits of a major Chinese hawthorn variety, Crataegus pinnatifida Bge. var. major, were separated by polyamide column chromatography, followed by analyses by high performance liquid chromatography combined with diode array UV spectrometry and electrospray ionization mass spectrometry. Ideain (cyanidin-3-O-galactoside), chlorogenic acid, procyanidin B2 [epicatechin-(4β → 8)-epicatechin], epicatechin, hyperoside (quercetin-3-O-galactoside) and isoquercitrin (quercetin-3-O-glucoside) were identified with UV spectra, mass spectra and reference compounds. In addition, 35 compounds were tentatively identified based on UV and mass spectra. These compounds were mostly B-type procyanidins (PA) and their glycosides including aglycons of 3 dimers, 3 trimers, 8 tetramers, 4 pentamers, 2 hexamers and 2 glycosides of PA monomers, 7 glycosides of PA dimers, 1 glycoside of a PA trimer, 2 glycosides of PA tetramers, 1 glycoside of a PA pentamer, and 2 glycosides of quercetin. This is the first systematic study of phenolic compounds in Chinese hawthorn fruits and the first report of the presence of glycosylated procyanidins in hawthorn.  相似文献   

20.
This work is focused on the synthesis of the fructooligosaccharides (FOS) from sucrose and inulin, using free, immobilized and pre-treated immobilized inulinase from Kluyveromyces marxianus NRRL Y 7571 and Aspergillus niger in an aqueous–organic system. Initially, the influence of pre-treatment using four different gases, propane, n-butane, CO2 and liquefied petroleum gas (LPG), was investigated towards FOS production and best results were found when both enzymes were previously treated with LPG. The best reaction yields were obtained when the immobilized enzymes were treated with LPG. Considering FOS synthesis using the enzyme from A. niger, yields of 26.62% of GF2 (kestose), 30.62% of GF3 (nystose) and 8.47% of GF4 (fructosyl nystose) were achieved using sucrose as substrate. Using inulinases from K. marxianus NRRL Y 7571, 11.89% of GF2 and 20.83% of GF3 were obtained, using inulin as substrate. However, promising results were achieved using the free form of inulinase from A. niger (77.19% of GF2; 14.03% of GF3 and 0.07% of GF4) using inulin as substrate.  相似文献   

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