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1.
The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA‐05 and its wild‐type variety Hwachia against aldose reductase, α‐glucosidase and α‐amylase were examined. The results indicated that the polyphenolics‐rich extracts obtained using 800 g kg?1 methanol and 500 g kg?1 ethanol demonstrated inhibitory activities against aldose reductase (IC50 of 0.36–0.46 mg mL?1) and α‐glucosidase (IC50 of 1.32–1.94 mg mL?1). The 500 g kg?1 ethanol extracts also showed α‐amylase inhibitory activities (IC50 of 70.11–80.22 μg mL?1). Subsequent extracts, prepared further with NaCl and H2O from precipitates of 800 g kg?1 methanol or 500 g kg?1 ethanol extracts, exhibited potent α‐amylase inhibitory activities (IC50 of 17.68–38.68 μg mL?1). A combination of 500 g kg?1 ethanol extraction plus a subsequent H2O extraction produced highest polyphenolics and α‐amylase inhibitors. The SA‐05 α‐amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA‐05 is an advantageous choice for producing anti‐hyperglycaemic compounds.  相似文献   

2.
Three phytosterols were isolated from Musa spp. flowers for evaluating their capabilities in inhibiting glucosidase and amylase activities and glycation of protein and sugar. The three phytosterols were identified as β‐sitosterol (PS1), 31‐norcyclolaudenone (PS2) and (24R)‐4α, 14α, 4‐trimethyl‐5α‐cholesta‐8, 25(27)‐dien‐3β‐ol (PS3). IC50 values (the concentration of inhibiting 50% of enzyme activity) of PS1, PS2 and PS3 against α‐glucosidase were 283.67, 11.33 and 43.10 μg mL?1, respectively. For inhibition of α‐amylase, the IC50 values of PS1, PS2 and PS3 were 52.55, 76.25 and 532.02 μg mL?1, respectively. PS1 was an uncompetitive inhibitor against α‐amylase with Km at 5.51 μg mL?1, while PS2 and PS3 exhibited a mixed‐type inhibition with Km at 52.36 and 2.49 μg mL?1, respectively. PS1 and PS2 also significantly inhibited the formation of advanced glycation end products (AGEs) in a BSA–fructose model. The results suggest that banana flower could possess the capability in prevention of the diseases associated with abnormal blood sugar and AGEs levels, such as diabetes.  相似文献   

3.
Physicochemical characterisation and oxidative stability of refined hoki oil, unrefined hoki oil and unrefined tuna oil were carried out in the present study. Tuna oil contains a higher percentage of polyunsaturated fatty acids (42.57%) than the hoki oils (28.79–30.13%), which have higher percentages of monounsaturated fatty acids (45.02–47.16%). All oils showed a good ratio of n‐3 to n‐6 fatty acid (7.01–8.10). Cholesterol contents in the unrefined hoki (5149.40 μg g?1) and tuna (2045.48 μg g?1) oils were higher than the refined hoki oil (1411.27 μg g?1). Tuna has a higher concentration of natural α‐tocopherol (752.49 μg g?1) but lower concentration of vitamin A (110.99 μg g?1) than unrefined hoki oil (151.44 μg g?1 and 997.60 μg g?1, respectively). Higher percentages of unsaponifiable matter were found in the hoki oils (4.90–7.24%) compared with the tuna oil (0.56%). The hoki oils appear more yellow than the tuna oil, which is darker by comparison. Moisture, p‐anisidine value and free fatty acid contents in the hoki oils were lower than the tuna oil. Other indicators of oxidative stability showed that the hoki oils were more stable than the tuna oil.  相似文献   

4.
Wheat α‐amylase inhibitors (AI) have been targeted as potential triggers of noncoeliac gluten or wheat sensitivity (NCGS). The aim of this study was to determine AI activity towards α‐amylase from human source in wheat cultivars. Contrary to barley, buckwheat, or oats, high level of AI activity was found in wheat and, to a lesser extent, rye. AI activity (mean IC50 = 137 μg mL?1) did not vary with respect to ancient or recently developed wheat cultivars. Vital wheat gluten had very high and heat‐stable AI activity (mean IC50 = 23 μg mL?1), higher than wheat starch (?10 000 μg mL?1) or acarbose (40 μg mL?1), a medication for the management of hyperglycaemia and potentially causing digestive disorders due to the accumulation of undigested carbohydrates in the intestine. Data suggest that eating raw wheat gluten, flour or dough could pose a health risk.  相似文献   

5.
The objective of this study was to determine the influence of 4‐ethylcatechol (4‐EC) on the sensory profile of Brettanomyces‐contaminated Merlot wine and evaluate electronic tongue discrimination. Using sensory evaluation panels, the consumer detection threshold (DT) and the consumer rejection threshold (CRT) of 4‐EC were determined in Merlot containing 493, 714, 1035 and 1500 μg L?1 4‐EC. The DT of 4‐EC in Merlot was 823 μg L?1, while the CRT was 1323 μg L?1. The electronic tongue discriminated index (DI = 82%) among the samples, with hierarchical clustering showing a clear distinction between the control sample and the spiked samples. The lowest concentration distinguished by the electronic tongue was 493 μg L?1, a lower value than the sensory threshold determined. These findings suggest that for the detection of 4‐EC in Merlot, the e‐tongue may be more sensitive than some consumers and the e‐tongue may be a suitable methodology for detection of subthreshold concentrations of chemical compounds in wine.  相似文献   

6.
Wheat bran was fermented at 28 °C for 7 days under 70% humidity by Aspergillus niger, Aspergillus oryzae and Aspergillus awamori. Total phenolic content (TPC) of the unfermented sample was 1531.5 μg g?1 wheat bran. After the fermentation of Aspergillus awamori, Aspergillus oryzae and Aspergillus niger, TPC reached 5362.1, 7462.6 and 10 707.5 μg g?1, respectively. The antioxidant activity in the extractions of fermented wheat bran also increased significantly compared with the unfermented sample (P < 0.05). Aspergillus niger showed the greatest capacity to release bound ferulic acid (416.6 μg g?1). Aspergillus oryzae and Aspergillus awamori had the advantages of releasing more chlorogenic acid (84.0 μg g?1) and syringic acid (142.3 μg g?1), respectively. The destructive effect of Aspergillus niger on wheat bran structure was the strongest, followed by that of Aspergillus oryzae. This effect of Aspergillus niger may be due to its higher cellulase, xylanase, arabinofuranosidase and β‐xylosidase activities. Besides, Aspergillus oryzae possessed higher β‐glucosidase activity, and Aspergillus awamori had higher α‐amylase and feruloyl esterase activities. Aspergillus niger may be the best to release bound phenolic acids in the three Aspergillus species. These will provide the helpful information for understanding mechanism of the fermentation by Aspergillus species releasing bound phenolic in wheat bran.  相似文献   

7.
A total of twenty‐eight mycotoxins were surveyed in wine (red, white and rose), cider (white and rose) and their cork stoppers from eight countries. Toxins of different fungi genera were detected as follows: Alternaria (ATs: alternariol – AOH; alternariol methyl – AME) and Penicillium/Aspergillus (ochratoxin A – OTA; penicillic acid – PAC). Toxins and levels varied with the sample types and country of origin. Wine presented contamination of OTA, AOH and AME. OTA was detected in forty‐one wine samples with levels ranging from 0.01 to 0.86 μg L?1, below EU legislation. AOH and AME were detected in thirty‐three and eight of wines samples, respectively, at levels from 0.2 to 13.3 μg L?1, while no contamination was detected in ciders up to the method LOQs. Regarding the cork stoppers toxins detected, they were AOH, AME and PAC. Corks of red wine from different countries had levels of OAH and AME ranging from 5.0 to 101.0 and 2.5 to 5 μg g?1, respectively. It is necessary to pay more attention on the corks processing and cork type used in the bottles as, different from the ordinary ones, the ground bark and compressed type did not have toxins detected.  相似文献   

8.
In this study, the efficacy of ginger (Zingiber officinale Roscoe) essential oil (GEO) in reducing A. flavus growth and aflatoxin production was investigated. Gas chromatography coupled to mass spectrometry and nuclear magnetic resonance spectroscopy showed that the major components of GEO were α‐zingiberene (23.85%) and geranial (14.16%). Mycelial growth of Aspergillus flavus was reduced significantly at a GEO concentration of 150 μg mL?1, and complete inhibition of conidial germination was observed at a concentration of 10 μg mL?1. Statistically significant inhibition of ergosterol biosynthesis was detected at a GEO concentration of 10 μg mL?1. GEO was capable of fully inhibiting aflatoxin production by A. flavus at a concentration of 15 μg mL?1. The results suggest that low concentrations of GEO are capable of inhibiting aflatoxin production; such ability could be valuable in the upcoming future for agricultural companies to better control aflatoxigenic fungi in agricultural products.  相似文献   

9.
Proximate composition, fatty acid profile, other nutritional values and spoilage indicators were examined in the muscle meat of five species: barramundi (Lates calcarifer) from various origins, tilapia (Oreochromis spp.) of different qualities, cobia (Rachycentron canadum) and leather jacket (Aluterus monoceros) from the Pacific Ocean and Patagonian grenadier (Macruronus magellanicus) from South America. Lowest lipid contents (0.4% and 0.8%) were found in leather jacket and cobia. Leather jacket fillets had lowest protein (16.2%) and highest sodium chloride content (4.9%). Concentrations of ∑EPA + DHA were 0.1 g 100 g?1 for tilapia and leather jacket, 0.2 g 100 g?1 for barramundi and cobia and 0.7 g 100 g?1 for Patagonian grenadier. Barramundi and tilapia were characterised by high taurine content (215 and 276 mg 100 g?1 ww.), and cobia had only low levels (41 mg 100 g?1 ww.). Iodine contents were low and selenium levels varied between 303 and 570 μg kg?1 ww. No sign of spoilage was detected.  相似文献   

10.
Commercially dried powder of nutmeg mace (Myristica fragrans) and pimento (Pimenta dioica) spices was investigated for their high performance liquid chromatography phenolic profile and their antioxidant and hypoglycaemic properties by α‐amylase and α‐glucosidase inhibition tests. Generally, mace showed the most promising activity. An interesting protection of lipid peroxidation with an IC50 value of 7.7 μg mL?1 was found. A significant result was also obtained in ferric reducing ability power assay if compared to the positive control butylated hydroxytoluene (IC50 value of 68.7 μg mL?1 vs. 63.2 μg mL?1, respectively). Mace also exhibited the highest carbohydrate‐hydrolysing enzyme inhibitory activity with IC50 values of 62.1 and 75.7 μg mL?1 against α‐amylase and α‐glucosidase, respectively. Overall, these results support the use of these spices not only as flavouring agent but also as food preservative and functional ingredients.  相似文献   

11.
Caxiri is a fermented alcoholic beverage made from cassava, corn and sweet potatoes by indigenous people in Brazil. Saccharomyces cerevisiae Rhodotorula mucilaginosa, Lactobacillus fermentum, Bacillus subtilis and L. helveticus were the main microbial species detected. Maltose was the main carbohydrate found (19.12 g L?1), and lactic acid (15.09 g L?1) and ethanol (92.16 g L?1) were also found in high concentrations. Gas chromatography‐flame ionisation detector was used to identify thirteen volatile compounds. Among these volatiles, the higher concentrations were decanoic acid (123.04 μg L?1) for the acids, diethyl malate (88.32 μg L?1) for the esters, furfural (109.31 μg L?1) for the aldehydes, 2‐phenylethanol (1022.76 μg L?1) for the alcohols and 1,1‐diethoxyethane (226.24 μg L?1) for the others. This study contributes to increasing knowledge of the microbiota present in the alcoholic fermentation produced from cassava, corn and sweet potatoes.  相似文献   

12.
The processing of peaches to produce fruit pulp generates solid and liquid wastes rich in phytochemicals, such as carotenoids; thus, the objective of this work was to study the use of this waste for carotenoid extraction based on a complete experimental design and using response surface methodology. The parameters studied were the amount of solvent (20–50 mL), the number of extractions (1–5) and the extraction time (10–30 min). The extracts were analysed by spectrophotometry and the optimised conditions by HPLC. The optimised results were four extractions of 10 min using 38.5 mL of ethanol, which presented a yield of 168.59 μg g?1 DW of total carotenoids of which 67.55 μg g?1 corresponds to β‐carotene, 86.75 μg g?1 to cryptoxanthin, 12.08 μg g?1 to zeaxanthin and 2.2 μg g?1 to lutein, which representing 66% of extraction pigments relative to the total content of carotenoids present in the peach waste.  相似文献   

13.
The objective of this study was to increase quality and limited shelf‐life of boza (3–15 days), a traditional Balkan origin fermented beverage using lysozyme (LYS) and/or nisin (NIS). For this purpose, the effectiveness of NIS, LYS and LYS:NIS combinations was first tested in a broth medium at 4 °C for 3 weeks on Lactobacillus plantarum, one of the frequently isolated lactic acid bacteria in boza. Stability of LYS and NIS in boza, their effects on LAB counts, and chemical and sensory properties of boza were then evaluated during cold storage at 4 °C. Results of LAB counts as well as pH, d ‐ and l ‐lactic acid, and titratable acidity measurements showed that LAB in boza containing NIS (250 μg g?1) or LYS:NIS (500:250 μg g?1) could be controlled without reducing LAB counts below 6 log CFU mL?1 during 2 weeks shelf‐life. In contrast, LYS (500 μg g?1) alone could not control LAB in boza to delay its acidic spoilage. Positive effects of NIS and LYS:NIS application on quality of boza were also proved with sensory analysis by panelists and e‐nose measurements. This work showed that use of natural GRAS agents in preservation of fermented beverages containing probiotic LAB is possible without affecting their characteristic aroma and flavour.  相似文献   

14.
This study reported the chemical composition, phenolic content, antioxidant and anti‐lipase activity of oregano and Lippia essential oils. The major compounds found in oregano essential oil were γ‐terpinene (32.10%), α‐terpinene (15.10%), p‐cymene (8.00%) and thymol (8.00%). In Lippia essential oil, α‐limonene (76.80%) and 1,8‐cineole (4.95%) represented the major compounds. Oregano essential oil had higher phenolic content (12.47 mg gallic acid mL?1) and DPPH scavenging activity (IC50 0.357 μg mL?1) than Lippia essential oil (7.94 mg gallic acid mL?1 and IC50 0.400 μg mL?1, respectively). Both essential oils had similar antioxidant indexes (about 1.2) determined by Rancimat. Moreover, oregano essential oil had also higher anti‐lipase activity (IC50 5.09 and 7.26 μg mL?1). Higher phenolic content in the essential oils was related with higher scavenging and anti‐lipase activities. Oregano and Lippia essential oils could be used as natural antioxidants on food products.  相似文献   

15.
Twelve commonly consumed culinary herbs were assessed for their potential effect in mitigating oxidative stress and postprandial hyperglycaemia: River Mint, Vietnamese Mint, Fish Mint, Spearmint, Sweet Basil, Thai Basil, Coriander, Lemon Verbena, Vietnamese Perilla, Rice Patty, Sawtooth and Rosemary. The radical scavenging and reducing antioxidant activity of the herbs were quite variable ranging from 31–652 mg Trolox Equivalent to 35–512 mg Ferrous Equivalent per gram dried leaves, respectively. The herbs were largely inactive against pancreatic α‐amylase, but showed strong inhibitions against yeast α‐glucosidase at 100 μg Gallic Acid Equivalent (GAE) per millilitre. Vietnamese Mint is the most potent herbs with the concentration required for 50% inhibition of activity of 6.9 μg Dried Leaves per millilitre. In addition, Vietnamese Mint was the only herb that produced significant inhibition of rat intestinal α‐glucosidases, reducing activity to 29.6% at 100 μg GAE mL?1 compared with control.  相似文献   

16.
ABSTRACT

Short-chain chlorinated paraffins (SCCPs) have drawn increasing interest worldwide since they were included in the list of controlled persistent organic pollutants in Annex A of the Stockholm Convention in 2017, and the potential health risk they pose to humans must be evaluated. In this study, 86 human milk samples were collected from 55 healthy Chinese mothers living in the Shijiazhuang region of Northern China in 2014–2015. Advanced online gel permeation chromatography–gas-chromatography-coupled mass spectrometry with negative-ion chemical ionisation was used to quantify the SCCPs in the samples. The estimated mean level of SCCPs was 2.51 μg g?1 lipid weight (range 0.21–16.12). The SCCP concentration correlated positively with the mother’s bodyweight at the end of pregnancy (P < 0.05). The mean SCCP intake by infants via breast milk was 13.0 μg kg?1 day?1 at 1 month, 7.1 μg kg?1 day?1 at 3 months, and 2.5 μg kg?1 day?1 at 6 months after birth. This study provides initial data on the levels of SCCPs in human milk in a chlorinated-paraffin-manufacturing area in China, and indicates a high health risk for infants.  相似文献   

17.
Effect of autochthonous starter cultures on the volatile flavour compounds of Chinese traditional fermented fish was studied. Lactobacillus plantarum 120, Staphylococcus xylosus 135 and Saccharomyces cerevisiae 31, isolated from Suan yu, were selected as starter cultures. Volatiles were extracted by headspace solid‐phase microextraction (SPME) and analysed by gas chromatography–mass spectrometry technology (GC‐MS). Esters and alcohols were the main components of volatiles, accounting for over 50 percentage points in all samples. The highest content of esters (3034.54 μg kg?1) was observed in S1 inoculated with L. plantarum 120, while the highest content of alcohols (2164.53 μg kg?1) and ketones (379.98 μg kg?1) was detected in S3 inoculated with S. cerevisiae 31. The content of acids and aldehydes was lower in inoculated samples. Principal component analysis revealed that the volatile composition was primarily influenced by the nature of the starter cultures. L. plantarum 120 and S. xylosus 135 could accelerate fermentation.  相似文献   

18.
Measuring the total phenolic content in wine is important in estimating the taste and health benefits of wine. We developed an automatic Folin–Ciocalteu (F‐C) method to reduce processing times (3 min), human errors and waste volume as compared it to the manual method. The gallic acid standard responded linearly up to 5000 μg mL?1, and the wine dilution series responded linearly between four‐ and sixteenfold dilutions. Anthocyanins showed slower reaction rate compared with wine, gallic acid and quercetin, while ascorbic acid showed the fastest rate. Fructose and glucose at the 10% level showed approximately 8% interference in port wines, and the interference was thought to be negligible in most dry wines containing <1% sugar. Total phenolic contents ranged between 1600 and 3300 μg mL?1 by the automatic method and were approximately 20% less than those by the manual method, except in pink wines which was nearly identical. The regression analysis of the phenolic contents showed a very linear relationship between the methods (r2 = 0.97***). This automatic method was thought to be efficiently adopted in wine testing laboratories as a fast and reproducible assay.  相似文献   

19.
3‐Monochloropropanediol (3‐MCPD) esters are contaminants produced from the high‐temperature processing of edible oils. The accurate measurement of 3‐MCPD using an easy‐to‐follow and reliable method that uses a readily available instrument is important. Here, we report an acid transesterification heptafluorobutyrylimidazole (HFBI) derivatisation method for the accurate measurement of 3‐MCPD esters in edible oils. We developed a dispersed matrix solid‐phase supported liquid–liquid extraction (DMSP‐SLE) system to remove impurities. Both the transesterification and DMSP‐SLE conditions were optimised. A good linear relationship was obtained within the range of 0.05–10 mg kg?1 (R2 ≥ 0.999) in both blank solvent and an oil sample. The limit of detection was 20.36 μg kg?1. The average recovery of the 3‐MCPD esters spiked at 0.5, 1.0 and 2.0 mg kg?1 into a blank oil matrix was in a range from 105.09 ± 2.77% to 120.16 ± 10.88%. The method we developed was further confirmed by performing detection on a Food Analysis Performance Assessment Scheme (FAPAS) sample.  相似文献   

20.
The study presents changes in the phenolic levels, antioxidant and anti‐inflammatory potential of purple basil leaves caused by different chemical elicitors: arachidonic acid (AA), jasmonic acid (JA) and β‐aminobutyric acid (BABA). The application of the all tested elicitors increased the concentration of phenolic compounds, including flavonoids and phenolic acids; especially, in comparison with control (457.62 μg g?1 FW), the rosmarinic acid level significantly increased after AA and JA treatment ‐ 705.0 and 596.5 μg g?1 FW, respectively. Phenolics from AA‐elicited plants showed the highest anti‐inflammatory activities designated as lipoxygenase (EC50 = 1.67 mg FW mL?1) and cyclooxygenase inhibition (EC50 = 0.31 mg FW mL?1). Elicitors' treatments (especially AA and JA) may be a very useful biochemical tool for improving the production of phenolic compounds in purple basil leaves.  相似文献   

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