Genome-wide association study of milk fatty acid composition in Italian Simmental and Italian Holstein cows using single nucleotide polymorphism arrays

Bovine milk is important for human nutrition, but its fat content is often criticized as a risk factor in cardiovascular disease. Selective breeding programs could be used to alter the fatty acid (FA) composition of bovine milk to improve the healthiness of dairy products for human consumption. Here, we performed a genome-wide association study (GWAS) on bovine milk to identify genomic regions or specific genes associated with FA profile and to investigate genetic differences between the Italian Simmental (IS) and Italian Holstein (IH) breeds. To achieve this, we first characterized milk samples from 416 IS cows and 436 IH cows for their fat profile by gas chromatography. Subjects were genotyped with single nucleotide polymorphism array and a single-marker regression model for GWAS was performed. Our findings confirm previously reported quantitative trait loci strongly associated with bovine milk fat composition. More specifically, our GWAS results revealed significant signals on chromosomes Bos taurus autosome 19 and 26 for milk FA. Further analysis using a gene-centric approach and pathway meta-analysis identified not only some well-known genes underlying quantitative trait loci for milk FA components, such as FASN, SCD, and DGAT1, but also other significant candidate genes, including some with functional roles in pathways related to “Lipid metabolism.” Highlighted genes related to FA profile include ECI2, PCYT2, DCXR, G6PC3, PYCR1, and ALG12 in IS, and CYP17A1, ACO2, PI4K2A, GOT1, GPT, NT5C2, PDE6G, POLR3H, and COX15 in IH. Overall, the breed-specific association outcomes reflect differences in the genetic backgrounds of the IS and IH breeds and their selective breeding histories.     

Corticosteroids in liver and urine in Sicilian cattle by a LC-MS/MS method

The presence of corticosteroid residues was assessed in urine and liver samples from livestock of Sicily. A total of 630 bovine samples were collected from farms and slaughterhouses. The samples were analysed using solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). All the corticosteroids found were under the maximum residue limit imposed by Commission Regulation (EC) 37/2010. About 4% of liver samples showed dexamethasone levels above the limit of detection (LOD), with a mean of 1.5 ± 0.2 µg kg^?1. Betamethasone was found only in seven liver samples, with a mean of 1.6 ± 0.1 µg kg^?1. Furthermore, prednisolone and prednisone were found only in urine and liver samples from slaughterhouse, probably related to the high rate of stress for bovines. These results suggest good control practices adopted by Sicilian farms, able to ensure the quality of food products.     

The Occurrence of Beer Spoilage Lactic Acid Bacteria in Craft Beer Production

Beer is one of the world's most ancient and widely consumed fermented alcoholic beverages produced with water, malted cereal grains (generally barley and wheat), hops, and yeast. Beer is considered an unfavorable substrate of growth for many microorganisms, however, there are a limited number of bacteria and yeasts, which are capable of growth and may spoil beer especially if it is not pasteurized or sterile‐filtered as craft beer. The aim of this research study was to track beer spoilage lactic acid bacteria (LAB) inside a brewery and during the craft beer production process. To that end, indoor air and work surface samples, collected in the brewery under study, together with commercial active dry yeasts, exhausted yeasts, yeast pellet (obtained after mature beer centrifugation), and spoiled beers were analyzed through culture‐dependent methods and PCR‐DGGE in order to identify the contaminant LAB species and the source of contamination. Lactobacillus brevis was detected in a spoiled beer and in a commercial active dry yeast. Other LAB species and bacteria ascribed to Staphylococcus sp., Enterobaceriaceae, and Acetobacter sp. were found in the brewery. In conclusion, the PCR‐DGGE technique coupled with the culture‐dependent method was found to be a useful tool for identifying the beer spoilage bacteria and the source of contamination. The analyses carried out on raw materials, by‐products, final products, and the brewery were useful for implementing a sanitization plan to be adopted in the production plant.     

External Shape Differences between Sympatric Populations of Commercial Clams <Emphasis Type="Italic">Tapes decussatus</Emphasis> and <Emphasis Type="Italic">T. philippinarum</Emphasis>

The actual Italian production of clams is chiefly sustained by the native Tapes decussatus and the fortuitously imported Tapes philippinarum. Both species are commercialized as “Vongola verace”, but the commercial value of T. philippinarum is lower. The discrimination of species by sight is usually difficult and it cannot be done by observation based on shell morphology but only when animals open their valves hence displaying the two siphons. In this study, we propose a new, noninvasive method to discriminate individuals of both species based on the analysis of the external shape of their shells. Accordingly, in sympatric populations at two sites of the Po river outlet, we have chosen individuals (63 for T. decussatus and 57 for T. philippinarum) of comparable commercial size for which a certain genetic discrimination was previously done. Pictures of the left side valve were taken for all specimens. Their profiles were analyzed with the elliptic Fourier analysis. The mean outline for each species was graphically extracted. The coefficients of the harmonic equations were analyzed by multivariate classification (partial least squares discriminant analysis [PLSDA]). Results showed a high percentage of correct classification of individuals of both species (96.6%). Contour analysis reflected the overall shell shape and thus identified morphological aspects that were difficult to recognize and quantify in sight. The high percentage of correct classifications obtained by combining the analysis of elliptic Fourier harmonics with PLSDA demonstrated the feasibility of this method to discriminate species with a high level of resemblance.     

Ranking the efficacies of selected red wine phenolic anti-oxidants using reversed-phase HPLC

Several studies have assessed total anti-oxidant activity of wine or individual components in isolation using chemical-based assays. In this study, a quantitative approach was developed to assess the relative anti-oxidant efficacies of selected red wine phenolics via peak reduction, using reversed-phase HPLC. Both intact red wine and phenolic standard solutions were challenged with five oxidant model systems as follows: (1) hydrogen peroxide (H₂O₂); redox-active metal ions (2) Fe³⁺ and (3) Cu²⁺; and the Fenton reagents (4) H₂O₂ + Fe²⁺; and (5) H₂O₂ + Cu⁺. Treatment with oxidants (1–3) resulted in loss of 47–60% of phenolic standards, which increased to 66–89% for treatment with the Fenton systems, with quercetin exhibiting the optimal anti-oxidant activity. For intact red wine, treatment with oxidants (1–3) led to all phenolic compounds being oxidised (27–77% loss), with caffeic acid and quercetin as the most effective anti-oxidants. For both Fenton systems (4–5), activities in red wine were considerably enhanced for caffeic acid and quercetin, which exhibited the highest anti-oxidant efficacies with 100% peak reduction, while p-coumaric acid and gallic acid were less effective anti-oxidants with peak reductions of 60–68%. The ranking, facilitated by this new quantitative approach, allows comparison of the individual efficacies of the anti-oxidants in a complex matrix.     

Effect of different levels of CO2 on the antioxidant content and the polyphenol oxidase activity of ‘Rocha’ pears during cold storage

Pears (Pyrus communis L. cv. ‘Rocha’) were exposed to air or controlled atmosphere (CA) containing various concentrations of CO₂: 0, 0.5 and 5 kPa, all with 2 kPa O₂. After 4 months of storage at 2 °C, the fruits were transferred to air at room temperature, and assessed in terms of soluble solids, titratable acidity, pH, incidence of brown heart and flesh browning, phenolic content, vitamin C content and polyphenol oxidase activity. By 4 months of storage, soluble solids and pH increased, and acidity decreased relative to harvest, but no differences were detected between pears stored under air or any of the CA tested. Higher contents of hydroxycinnamic derivatives and flavan‐3‐ols in the peel than in the flesh were recorded. However, the content of arbutin was higher in the flesh than in the peel, whereas flavonols were only detected in the peel. In general, hydroxycinnamic derivatives and flavonols were stable throughout storage, but flavan‐3‐ols decreased in concentration under air or CA. Arbutin was the only phenolic compound that increased in concentration as time elapsed. No clear relation was found between the storage conditions tested and the phenolic concentration in pears. Regarding ascorbic acid (AA) and dehydroascorbic acid (DHA), their concentrations were higher in the peel than in the flesh. Furthermore, AA and DHA were strongly affected by storage: the former decreased, whereas the latter increased in content. A decrease in PPO activity was apparent after harvest and during storage, particularly under higher levels of CO₂. The combination 2 kPa O₂ + 5 kPa CO₂ increased the incidence of internal disorders (viz. brown heart and flesh browning) after storage. Copyright © 2005 Society of Chemical Industry     

Evaluation of an alkaline phosphatase-labeled oligonucleotide probe for the detection and enumeration of the thermostable-related hemolysin (trh) gene of Vibrio parahaemolyticus

Reliable methods are needed to detect total and pathogenic Vibrio parahaemolyticus. One marker of V. parahaemolyticus virulence is the thermostable-related hemolysin. We developed an alkaline phosphatase-labeled DNA probe method for the specific detection and enumeration of trh-positive V. parahaemolyticus by colony hybridization. The probe was tested against a panel of 200 bacterial strains and determined to be specific for trh-positive V. parahaemolyticus. Additionally, the trh alkaline phosphatase probe colony hybridization was successfully used to detect and enumerate trh-positive V. parahaemolyticus in seafood and water samples collected from the United States and the United Kingdom.     

Common wheat (Triticum aestivum L.) and its use as a brewing cereal – a review

Wheat (Triticum aestivum L.) has a long tradition as a raw material for the production of malt and beer. Nevertheless, it has been studied to a much lesser extent than barley, which is the number one brewing cereal. The protein content of wheat ranges from about 6 to 20%, depending on the variety and baking characteristics, as well as on environmental conditions during growth. Since wheat is the most used cereal in the baking industry, the focus of wheat breeding and research has been about optimization for baking purposes (i.e. high protein content, stable falling numbers, constant baking qualities). It is well known that wheat varieties with a high protein content lead to problems in the brewing process. Therefore, varieties with a low protein content and with low viscosity values are favoured for malting and brewing. Since wheat beer yield has nearly doubled from 1990 to 2009, and is still increasing, more focus has been placed on conducting research on wheat for the malting and brewing industry. Currently, every tenth beer sold in Germany is a wheat beer. Therefore, it is of major interest to screen wheat varieties for brewing processability and to give more focus to wheat as a brewing cereal. In this review, a detailed characterization of wheat is given, particularly in regard to carbohydrates, pentosans, protein fractions and enzymes. The impact of wheat and its quality on the malting and brewing process is reviewed. Copyright © 2014 The Institute of Brewing & Distilling