50 assays (manual) / 500 assays (microplate) / 500 assays (auto-analyser)
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|Content:||50 assays (manual) / 500 assays (microplate) / 500 assays (auto-analyser)|
Short term stability: 2-8oC,
Long term stability: See individual component labels
|Stability:||> 2 years under recommended storage conditions|
|Assay Format:||Spectrophotometer, Microplate, Auto-analyser|
|Linear Range:||0.5 to 20 µg of acetaldehyde per assay|
|Limit of Detection:||0.18 mg/L|
|Reaction Time (min):||~ 4 min|
|Application examples:||Wine, champagne, beer, liqueurs, brandy, dairy products (e.g. yogurt), bread, fruit juices, soft drinks, cocoa, vegetable and fruit products, coffee, and other materials (e.g. biological cultures, samples, etc.).|
|Method recognition:||Methods based on this principle have been accepted by MEBAK|
The Acetaldehyde test kit is a simple, reliable and accurate method for the measurement and analysis of acetaldehyde in beverages and foodstuffs.
Note for Content: The number of manual tests per kit can be doubled if all volumes are halved. This can be readily accommodated using the MegaQuantTM Wave Spectrophotometer (D-MQWAVE).
- Extended cofactors stability. Dissolved cofactors stable for > 1 year at 4oC.
- No wasted aldehyde dehydrogenase solution (stable suspension supplied)
- Very competitive price (cost per test)
- All reagents stable for > 2 years after preparation
- Simple format
- Mega-Calc™ software tool is available from our website for hassle-free raw data processing
- Standard included
- Suitable for manual, microplate and auto-analyser formats
Megazyme “advanced” wine test kits general characteristics and validation.
Charnock, S. J., McCleary, B. V., Daverede, C. & Gallant, P. (2006). Reveue des Oenologues, 120, 1-5.
Many of the enzymatic test kits are official methods of prestigious organisations such as the Association of Official Analytical Chemicals (AOAC) and the American Association of Cereal Chemists (AACC) in response to the interest from oenologists. Megazyme decided to use its long history of enzymatic bio-analysis to make a significant contribution to the wine industry, by the development of a range of advanced enzymatic test kits. This task has now been successfully completed through the strategic and comprehensive process of identifying limitations of existing enzymatic bio-analysis test kits where they occurred, and then using advanced techniques, such as molecular biology (photo 1), to rapidly overcome them. Novel test kits have also been developed for analytes of emerging interest to the oenologist, such as yeast available nitrogen (YAN; see pages 2-3 of issue 117 article), or where previously enzymes were simply either not available, or were too expensive to employ, such as for D-mannitol analysis.Hide Abstract
Grape and wine analysis: Oenologists to exploit advanced test kits.
Charnock, S. C. & McCleary, B. V. (2005). Revue des Enology, 117, 1-5.
It is without doubt that testing plays a pivotal role throughout the whole of the vinification process. To produce the best possible quality wine and to minimise process problems such as “stuck” fermentation or troublesome infections, it is now recognised that if possible testing should begin prior to harvesting of the grapes and continue through to bottling. Traditional methods of wine analysis are often expensive, time consuming, require either elaborate equipment or specialist expertise and frequently lack accuracy. However, enzymatic bio-analysis enables the accurate measurement of the vast majority of analytes of interest to the wine maker, using just one piece of apparatus, the spectrophotometer (see previous issue No. 116 for a detailed technical review). Grape juice and wine are amenable to enzymatic testing as being liquids they are homogenous, easy to manipulate, and can generally be analysed without any sample preparation.Hide Abstract
Sung, C. K., Kim, S. M., Oh, C. J., Yang, S. A., Han, B. H. & Mo, E. K. (2012). Food and Chemical Toxicology, 50(7), 2508-2514.
The present study, taraxerone (D-friedoolean-14-en-3-one) was isolated from Sedum sarmentosum with purity 96.383%, and its enhancing effects on alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activities were determined: EC50 values were 512.42 ± 3.12 and 500.16 ± 3.23 µM for ADH and ALDH, respectively. In order to obtain more information on taraxerone related with the alcohol metabolism, 40% ethanol (5 mL/kg body weight) with 0.5–1 mM of taraxerone were administered to mice. The plasma alcohol and acetaldehyde concentrations of taraxerone-treated groups were significantly lowered than those of the control group (p < 0.01): approximately 20–67% and 7–57% lowered for plasma alcohol and acetaldehyde, respectively. Compare to the control group, the ADH and ALDH expressions in the liver tissues were abruptly increased in the taraxerone-treated groups after ethanol exposure. In addition, taraxerone prevented catalase, superoxide dismutase, and reduced glutathione concentrations from the decrease induced by ethanol administration with the concentration dependent manner.Hide Abstract
Cho, S. Y., Yun, J. W., Park, P. J., Sohn, J. H., Seo, D. B., Lim, K. M., Kim, W. G. & Lee, S. J. (2010). Journal of Medicinal Food, 13(5), 1061-1068.
Chitooligosaccharides (COS), a kind of oligosaccharide made from chitin or chitosan, have been used a popular remedy for hangovers. In this study we investigated the in vitro effect of COS lactate salt on ethanol-induced cytotoxicity and the in vitro effect of short-term COS lactate salt feeding on ethanol-induced hangover. Pretreatment of HepG2 cells with COS lactate salt significantly reduced ethanol-induced cytotoxicity and suppressed generation of reactive oxygen species. In addition, COS lactate salt dose-dependently increased acetaldehyde dehydrogenase (ALDH) activity in vitro and reversed the ALDH inhibition induced by daidzin. Furthermore, oral administration of COS lactate salt (200 mg/kg) for 5 days significantly decreased the blood levels of alcohol and acetaldehyde in ethanol-treated mice. It was also demonstrated that hepatic mitochondrial ALDH activity was significantly increased in COS lactate salt-treated mice. Taken together, these findings indicate that COS lactate salt may have efficacy for the management of alcoholic hangovers.Hide Abstract
Zara, G., Mannazzu, I., Sanna, M. L., Orro, D., Farris, G. A. & Budroni, M. (2008). FEMS Yeast Research, 8(7), 1147-1154.
A strain of Saccharomyces cerevisiae having desirable winemaking properties and high spore viability was bred from a semi-homothallic parent strain with similar winemaking properties but that produced sixfold fewer viable spores. Because the parent was homozygous for HO and for the MATa allele at both silent HMR and HML loci, it produced two MATa and two nonmating progeny per ascus. To obtain a segregant able to mate with the stable MATa progeny, a strain of the nonmating progeny, previously subjected to HO distruption with a KanMX4 cassette, was used. The resultant MATαho::KanMX4 transformant was mated to a MATa HO segregant and the diploid produced was sporulated to allow the isolation of a semi-homothallic diploid segregant designated 2D that lacked the KanMX4 -disrupted HO allele as confirmed by sequence analysis. Genetic analysis indicated greater homozygosity in 2D than in the parent as assessed by PCR at five loci. The sugar consumption profiles of both 2D and the parent in grape juice fermentations were the same. Acetaldehyde levels and postfermentation biofilm formation were higher in 2D than in the parent. Because 2D has acceptable winemaking characteristics but produces significantly more viable spores than the parent strain, it will be useful in future breeding efforts.Hide Abstract
Ha, J. H., Shah, N., Ul-Islam, M. & Park, J. K. (2011). Enzyme and Microbial Technology, 49(3), 298-304.
The potential of the waste from beer fermentation broth (WBFB) for the production of bio-ethanol using a simultaneous saccharification and fermentation process without any extra additions of saccharification enzymes, microbial cells or carbohydrate was tested. The major microbial cells in WBFB were isolated and identified. The variations in compositions of WBFB with stock time were investigated. There was residual activity of starch hydrolyzing enzymes in WBFB. The effects of reaction modes, e.g. static and shaking on bio-ethanol production were studied. After 7 days of cultivation using the supernatant of WBFB at 30°C the ethanol concentration reached 103.8 g/L in shaking culture and 91.5 g/L in static culture. Agitation experiments conducted at a temperature-profile process in which temperature was increased from 25 to 67°C shortened the simultaneous process time. The original WBFB was more useful than the supernatant of WBFB in getting the higher concentration of ethanol and reducing the fermentation time. From this whole study it was found that WBFB is a cheap and suitable source for bio-ethanol production.Hide Abstract
Luo, Z., Walkey, C. J., Madilao, L. L., Measday, V. & Vuuren, H. J. (2013). FEMS Yeast Research, 13(5), 485-494.
Control of volatile acidity (VA) is a major issue for wine quality. In this study, we investigated the production of VA by a deletion mutant of the fermentation stress response gene AAF1 in the budding yeast Saccharomyces cerevisiae. Fermentations were carried out in commercial Chardonnay grape must to mimic industrial wine-making conditions. We demonstrated that a wine yeast strain deleted for AAF1 reduced acetic acid levels in wine by up to 39.2% without increasing the acetaldehyde levels, revealing a potential for industrial application. Deletion of the cytosolic aldehyde dehydrogenase gene ALD6 also reduced acetic acid levels dramatically, but increased the acetaldehyde levels by 41.4%, which is not desired by the wine industry. By comparison, ALD4 and the AAF1 paralog RSF2 had no effects on acetic acid production in wine. Deletion of AAF1 was detrimental to the growth of ald6Δ and ald4Δald6Δ mutants, but had no effect on acetic acid production. Overexpression of AAF1 dramatically increased acetic acid levels in wine in an Ald6p-dependent manner, indicating that Aaf1p regulates acetic acid production mainly via Ald6p. Overexpression of AAF1 in an ald4Δald6Δ strain produced significantly more acetic acid in wine than the ald4Δald6Δ mutant, suggesting that Aaf1p may also regulate acetic acid synthesis independently of Ald4p and Ald6p.Hide Abstract
Abraham, J., Balbo, S., Crabb, D. & Brooks, P. J. (2011). Alcoholism: Clinical and Experimental Research, 35(12), 2113-2120.
Background: We recently reported that exposure of human cells in vitro to acetaldehyde resulted in activation of the Fanconi anemia-breast cancer associated (FA-BRCA) DNA damage response network. Methods: To determine whether intracellular generation of acetaldehyde from ethanol metabolism can cause DNA damage and activate the FA-BRCA network, we engineered HeLa cells to metabolize alcohol by expression of human alcohol dehydrogenase 1B. Results: Incubation of HeLa-ADH1B cells with ethanol (20 mM) resulted in acetaldehyde accumulation in the media which was prevented by co-incubation with 4-methyl pyrazole (4-MP), a specific inhibitor of ADH. Ethanol treatment of HeLa-ADH1B cells produced a 4-fold increase in the acetaldehyde-DNA adduct, N2-ethylidene-dGuo, and also resulted in activation of the Fanconi anemia-breast cancer susceptibility (FA-BRCA) DNA damage response network, as indicated by a monoubiquitination of FANCD2, and phosphorylation of BRCA1. Ser 1524 was identified as one site of BRCA1 phosphorylation. The increased levels of DNA adducts, FANCD2 monoubiquitination, and BRCA1 phosphorylation were all blocked by 4-MP, indicating that acetaldehyde, rather than ethanol itself, was responsible for all three responses. Importantly, the ethanol concentration we used is within the range that can be attained in the human body during social drinking. Conclusions: Our results indicate that intracellular metabolism of ethanol to acetaldehyde results in DNA damage which activates the FA-BRCA DNA damage response network.Hide Abstract
Principato, M., Boyle, T., Njoroge, J., Jones, R. L. & O'Donnell, M. (2009). Journal of Food Protection®,72(10), 2212-2216.
This research was conducted to examine the inherent properties of yogurt contaminated with staphylococcal enterotoxin B (SEB). Two types of yogurts were produced for this study. Type I yogurts were produced by adding SEB at the start of yogurt production, and type II yogurts were produced by adding SEB after the milk base had been boiled. Biochemical characteristics inherent to yogurt, including pH, lactic acid and acetaldehyde concentrations, were analyzed weekly for each batch beginning at a time just after production and throughout a storage period of at least 4 weeks. The presence of toxin during yogurt production did not result in any significant biochemical or physical changes in yogurt. However, we were unable to detect SEB toxin in type I yogurt using a commercially available enzyme-linked immunosorbent assay (ELISA). In contrast, SEB was easily detectable by our ELISA in type II yogurt samples. Higher levels of SEB were recovered from type II yogurt that had been stored for 1 week than from type II yogurt that had been stored for any other length of time. These results indicate that the biochemical characteristics of yogurt did not change significantly (relative to control yogurt) in the presence of either thermally processed SEB or native SEB. However, the ability to detect SEB by ELISA was dependent on whether the toxin had been processed.Hide Abstract
Liu, W., Yu, J., Sun, Z., Song, Y., Wang, X., Wang, H., Wuren, T., Zha, M., Menghe, B. & Heping, Z. (2016). Journal of dairy science, 99(1), 89-103.
Lactobacillus delbrueckii ssp. bulgaricus (L. bulgaricus) is well known for its worldwide application in yogurt production. Flavor production and acid producing are considered as the most important characteristics for starter culture screening. To our knowledge this is the first study applying functional gene sequence multilocus sequence typing technology to predict the fermentation and flavor-producing characteristics of yogurt-producing bacteria. In the present study, phenotypic characteristics of 35 L. bulgaricus strains were quantified during the fermentation of milk to yogurt and during its subsequent storage; these included fermentation time, acidification rate, pH, titratable acidity, and flavor characteristics (acetaldehyde concentration). Furthermore, multilocus sequence typing analysis of 7 functional genes associated with fermentation time, acid production, and flavor formation was done to elucidate the phylogeny and genetic evolution of the same L. bulgaricus isolates. The results showed that strains significantly differed in fermentation time, acidification rate, and acetaldehyde production. Combining functional gene sequence analysis with phenotypic characteristics demonstrated that groups of strains established using genotype data were consistent with groups identified based on their phenotypic traits. This study has established an efficient and rapid molecular genotyping method to identify strains with good fermentation traits; this has the potential to replace time-consuming conventional methods based on direct measurement of phenotypic traits.Hide Abstract
Li, E. & de Orduña, R. M. (2016). Journal of Industrial Microbiology & Biotechnology, 144, 229-236.
Acetaldehyde strongly binds to the wine preservative SO2 and, on average, causes 50-70 mg l-1 of bound SO2 in red and white wines, respectively. Therefore, a reduction of bound and total SO2 concentrations necessitates knowledge of the factors that affect final acetaldehyde concentrations in wines. This study provides a comprehensive analysis of the acetaldehyde production and degradation kinetics of 26 yeast strains of oenological relevance during alcoholic fermentation in must under controlled anaerobic conditions. Saccharomyces cerevisiae and non-Saccharomyces strains displayed similar metabolic kinetics where acetaldehyde reached an initial peak value at the beginning of fermentations followed by partial reutilization. Quantitatively, the range of values obtained for non-Saccharomyces strains greatly exceeded the variability among the S. cerevisiae strains tested. Non-Saccharomyces strains of the species C. vini, H. anomala, H. uvarum, and M. pulcherrima led to low acetaldehyde residues (-1), while C. stellata, Z. bailii, and, especially, a S. pombe strain led to large residues (24-48 mg l-1). Acetaldehyde residues in S. cerevisiae cultures were intermediate and less dispersed (14-34 mg l-1). Addition of SO2 to Chardonnay must triggered significant increases in acetaldehyde formation and residual acetaldehyde. On average, 0.33 mg of residual acetaldehyde remained per mg of SO2 added to must, corresponding to an increase of 0.47 mg of bound SO2 per mg of SO2 added. This research demonstrates that certain non-Saccharomyces strains display acetaldehyde kinetics that would be suitable to reduce residual acetaldehyde, and hence, bound-SO2 levels in grape wines. The acetaldehyde formation potential may be included as strain selection argument in view of reducing preservative SO2 concentrations.Hide Abstract
Müller, M. F., Zhou, Y., Adams, D. J. & Arends, M. J. (2016). The Journal of Pathology, 241(5), 649-660.
Ethanol and its metabolite acetaldehyde have been classified as carcinogens for the upper aerodigestive tract, liver, breast and colorectum. Whereas mechanisms related to oxidative stress and Cyp2e1 induction seem to prevail in the liver, and acetaldehyde has been proposed to play a crucial role in the upper aerodigestive tract, pathological mechanisms in the colorectum have not yet been clarified. Moreover, all evidence for a pro-carcinogenic role of ethanol in colorectal cancer is derived from correlations observed in epidemiological studies or from rodent studies with additional carcinogen application or tumour suppressor gene inactivation. In the current study, wildtype mice and mice with depletion of aldehyde dehydrogenase 1b1 (Aldh1b1), an enzyme which has been proposed to play an important role in acetaldehyde detoxification in the intestines, received ethanol in drinking water for one year. Long-term ethanol consumption led to intestinal tumour development in wildtype and Aldh1b1-depleted mice, but no intestinal tumours were observed in water-treated controls. Moreover, a significant increase in DNA damage was detected in the large intestinal epithelium of ethanol-treated mice of both genotypes compared with the respective water-treated groups, along with increased proliferation of the small and large intestinal epithelium. Aldh1b1 depletion led to increased plasma acetaldehyde levels in ethanol-treated mice, to a significant aggravation of ethanol-induced intestinal hyperproliferation, and to more advanced features of intestinal tumours, but it did not affect intestinal tumour incidence. These data indicate that ethanol consumption can initiate intestinal tumourigenesis without any additional carcinogen treatment or tumour suppressor gene inactivation, and we provide evidence for a role of Aldh1b1 in protection of the intestines from ethanol-induced damage, as well as for both carcinogenic and tumour-promoting functions of acetaldehyde, including increased progression of ethanol-induced tumours.Hide Abstract
Zachut, M., Shapiro, F. & Silanikove, N. (2016). Food chemistry, 201, 270-274.
There is a need for simple, accurate, and rapid analysis of ethanol (Eth) and acetaldehyde (AA) in a wide variety of beverages and foods. A novel enzymatic assay coupled to formation of fluorescent chromophore is presented. Eth detection was further improved by adding semicarbazide to the reaction mixture, which interacts with AA and prevents its inhibitory effect on Eth oxidation. The limits of detection of Eth (0.5 mg/L) and AA (0.9 mg/L) are comparable with the performance of modern gas chromatography techniques. The repeatability of Eth and AA detection in various foods (9% on average) was lower than that with commercial kits (23%). The high sensitivity of the developed method enables detection of AA in common foods [e.g., bio-yogurt (12.2 mg/L), and the existence of endogenous Eth (1.8 mg/L) and AA (2.0 mg/L) in bacteria-free non-fermented bovine milk], which could not measured so far by enzymatic methods.Hide Abstract
Quintana, G., Gerbino, E. & Gómez-Zavaglia, A. (2017). Frontiers in Microbiology, 8, 641.
Okara is a nutritionally valuable by-product produced in large quantities as result of soymilk elaboration. This work proposes its use as both culture and dehydration medium during freeze-drying, spray-drying, and storage of Lactobacillus plantarum CIDCA 83114. Whole and defatted okara were employed as culture media for L. plantarum CIDCA 83114. The growth kinetics were followed by plate counting and compared with those of bacteria grown in MRS broth (control). No significant differences in plate counting were observed in the three media. The fatty acid composition of bacteria grown in whole and defatted okara showed a noticeable increase in the unsaturated/saturated (U/S) fatty acid ratio, with regard to bacteria grown in MRS. This change was mainly due to the increase in polyunsaturated fatty acids, namely C18:2. For dehydration assays, cultures in the stationary phase were neutralized and freeze-dried (with or without the addition of 250 mM sucrose) or spray-dried. Bacteria were plate counted immediately after freeze-drying or spray-drying and during storage at 4°C for 90 days. Freeze-drying in whole okara conducted to the highest bacterial recovery. Regarding storage, spray-dried bacteria previously grown in whole and defatted okara showed higher plate counts than those grown in MRS. On the contrary, freeze-dried bacteria previously grown in all the three culture media were those with the lowest plate counts. The addition of sucrose to the dehydration media improved their recovery. The higher recovery of microorganisms grown in okara after freeze-drying and spray-drying processes and during storage was ascribed to both the presence of fiber and proteins in the dehydration media, and the increase in U/S fatty acids ratio in bacterial membranes. The obtained results support for the first time the use of okara as an innovative matrix to deliver L. plantarum. Considering that okara is an agro-waste obtained in large quantities, these results represent an innovative strategy to add it value, providing a symbiotic ingredient with promising industrial applications in the development of novel functional foods and feeds.Hide Abstract
Roda, A., Lucini, L., Torchio, F., Dordoni, R., De Faveri, D. M. & Lambri, M. (2017). Food Chemistry, 229, 734-742.
Vinegar is an inexpensive commodity, and economic considerations require that a relatively low-cost raw material be used for its production. An investigation into the use of a new, alternative substrate - pineapple waste - is described. This approach enables the utilization of the pineapple’s (Ananas comosus) peels and core, which are usually discarded during the processing or consumption of the fruit. Using physical and enzymatic treatments, the waste was saccharified, and the resulting substrate was fermented with Saccharomyces cerevisiae for 7-10 days under aerobic conditions at 25°C. This resulted in an alcohol yield of approximately 7%. The alcoholic medium was then used as a seed broth for acetic fermentation using Acetobacter aceti as the inoculum for approximately 30 days at 32°C to obtain 5% acetic acid. Samples were analyzed at the beginning and end of the acetification cycle to assess the volatile and fixed compounds by GC-MS and UHPLC-QTOF-MS. The metabolomic analysis indicated that L-lysine, mellein, and gallic acid were significantly more concentrated in the pineapple vinegar than in the original wine. Higher alcohols, aldehydes, and ketones characterized the aroma of the final pineapple vinegar, whilst off-flavors were significantly reduced relative to the initial wine. This study is the first to highlight the metabolite profile of fruit vinegar with a slight floral aroma profile derived from pineapple waste. The potential to efficiently reduce the post-harvest losses of pineapple fruits by re-using them for products with added food values is also demonstrated.Hide Abstract
Guerreiro, A. C., Gago, C. M., Miguel, M. G., Faleiro, M. L. & Antunes, M. D. (2016). Food Packaging and Shelf Life, 9, 20-28.
Due to the high perishability of raspberry fruit, this work was undertaken to study the effect of alginate and pectin based edible coatings enriched with essential oils components on their storage ability. Four formulations of edible coatings, selected in a previous work, were used: sodium alginate (AL) at 2% + eugenol (Eug) 0.1%, AL 2% + citral (Cit) 0.15%, Pectin (PE) 1% + Eug 0.1% and PE 1% + Cit 0.15% + Eug 0.1%. At 0, 5, 10 and 15 d, samples were taken to perform analysis of colour, firmness, soluble solids content (SSC), weight loss, microbial growth, phenolic compounds (total phenolics, flavonoids, anthocyanins), sugars, organic acids, antioxidant activity (TEAC and ORAC), acetaldehyde, CO2 production and sensory evaluation. Cytotoxicity of the edible coatings was also evaluated on THP-1 and Caco-2 cells. Results of this experiment showed that the edible coatings were not cytotoxic and generally did not significantly affect nutritional quality parameters. They were efficient in controlling microbial food spoilage. Acceptance by consumers of the coated raspberries was good up to 14 d, while control fruit were acceptable only till 7 d. The edible coating that best preserved quality was PE 1% + Cit 0.15% + Eug 0.1%.Hide Abstract
Yang, F., Heit, C. & Inglis, D. L. (2017). Fermentation, 3(4), 61.
Acetic acid is undesired in Icewine. It is unclear whether its production by fermenting yeast is linked to the nicotinamide adenine dinucleotide (NAD+/NADH) system or the nicotinamide adenine dinucleotide phosphate (NADP+/NADPH) system. To answer this question, the redox status of yeast cytosolic NAD(H) and NADP(H) were analyzed along with yeast metabolites to determine how redox status differs under Icewine versus table wine fermentation. Icewine juice and dilute Icewine juice were inoculated with commercial wine yeast Saccharomyces cerevisiae K1-V1116. Acetic acid was 14.3-fold higher in Icewine fermentation than the dilute juice condition. The ratio of NAD+ to total NAD(H) was 24-fold higher in cells in Icewine fermentation than the ratio from the dilute juice condition. Conversely, the ratio of NADP+ to total NADP(H) from the dilute fermentation was 2.9-fold higher than that in the Icewine condition. These results support the hypothesis that in Icewine, increased NAD+ triggered the catalysis of NAD+-dependent aldehyde dehydrogenase(s) (Aldp(s)), which led to the elevated level of acetic acid in Icewine, whereas, in the dilute condition, NADP+ triggered NADP+-dependent Aldp(s), resulting in a lower level of acetic acid. This work, for the first time, analyzed the yeast cytosolic redox status and its correlation to acetic acid production, providing a more comprehensive understanding of the mechanism of acetic acid production in Icewine.Hide Abstract
Benucci, I., Cerreti, M., Liburdi, K., Nardi, T., Vagnoli, P., Ortiz-Julien, A. & Esti, M. (2018). Food Research International, 107, 257-266.
Two different Metschnikowia strains (M. pulcherrima MP 346 or M. fructicola MF 98-3) were applied for the first time, during pre-fermentative cold maceration (PCM) in order to enhance the properties and stability of Sangiovese wine color. During the 2014 and 2015 vintages a total of eight wines were produced with 24 h of cold maceration (PCM 24 h) or 72 h (PCM 72 h), respectively. PCM was carried out in presence of MP 346 or MF 98-3 or pectic enzyme (Cuvée Rouge). The sequential inoculation of S. cerevisiae strain was carried out at the end of PCM. After 12 months in the bottle, the MP 346 and MF 98-3 wines contained much higher levels of total flavonoids than the Control sample for both vintages and regardless PCM duration. Moreover, in both vintages only MF 98-3 showed a higher color intensity than the Control sample after 12 months in the bottle. However, neither PCM duration nor the microbial/enzymatic treatment increased the level of anthocyanins at draining off. Both wines produced by the pre-fermentative inoculum with Metschnikowia strains (MP 346 and MF 98-3) retained their red hue, regardless the duration of pre-fermentative and fermentative macerations, while the Control wines were characterized by faster rates of color loss.Hide Abstract
Zhang, Y., Wang, C., Yu, B., Jiang, J. D. & Kong, W. J. (2018). Biological and Pharmaceutical Bulletin, 41(5), 670-679.
This study aims to investigate the protective effects of gastrodin (GSTD), a natural compound isolated from the root of Gastrodia elata BL., on ethanol-induced liver injury and apoptosis in HepG2 cells and animal models. For in vitro studies, GSTD was used to pre-treat the cells for 4 h followed by 600 mM of ethanol co-administration for 24 h. Alcoholic liver disease (ALD) of Sprague-Dawley (SD) rats was induced by chronic ethanol-feeding plus a single dose (5 g/kg) of acute ethanol administration, GSTD at different doses were co-administered for 8 weeks. For acute liver injury experiment of ICR mice, GSTD (100 mg/kg/d) was pre-treated for 3 d followed by ethanol administration (5 g/kg) for 3 times. The results showed that GSTD protects HepG2 cells from ethanol-induced toxicity, injury, and apoptosis significantly. Co-administered with ethanol, GSTD prevented the loss of mitochondrial membrane potential, reduced the release cytochrome c from mitochondria, and inhibited the activation of caspase-3 in HepG2 cells. In SD rats induced by chronic ethanol-feeding, GSTD significantly restored liver function and ameliorated pathological changes of the liver. In rat liver, GSTD greatly suppressed the activation of caspase-3 and inhibited hepatocellular apoptosis. In ethanol-induced acute liver injury of ICR mice, GSTD reduced liver acetaldehyde and suppressed the up-regulation of alcohol dehydrogenase (ADH) and CYP2E1 significantly. Our results demonstrate that GSTD is efficacious in protecting liver cells from ethanol-induced injury and apoptosis; it may be useful for the development of novel agents for the treatment of ALD in the future.Hide Abstract