Thermal and chemical inactivation of lactococcal bacteriophages

Ten lactococcal bacteriophages in M17 broth were treated by heat (72 °C, 15 min and 90 °C, 5 min), ethanol and isopropanol at concentrations of 10%, 50%, 75% and 100% (v/v). The heat treatments were not sufficient to inactivate all the bacteriophages studied whereas ethanol, which was also more efficient biocide than isopropanol, at a concentration of 75% could inactivate all the phages in 1 min. The 50% and 75% of ethanol were more effective than 100%, which was also observed for isopropanol. Survival curves’ deviations from linearity as sigmoidal shapes could be described via an empirical model with four parameters. The parameters of the model could be reduced from four to two with a slight loss of goodness-of-fit. The reduced model also provided good fit to describe the isopropanol inactivation kinetics of the phages at concentrations of 50% and 75%. This demonstration may also be a useful tool for further inactivation studies in which ethanol or other biocides are used with sufficient survival data points at selected time intervals. Although more studies should be carried out with different phages, this study confirmed the lethal effect of ethanol, commonly used to disinfect utensils and laboratory equipment, on lactoccocal bacteriophages.     

Effects of fermentation time and storage on the water‐soluble vitamin contents of tarhana

Changes in water‐soluble vitamins were investigated in tarhana dough during fermentation and in tarhana stored under a variety of conditions for up to 6 months. The contents of riboflavin (P < 0.01), thiamin, niacin, vitamin B₆ and folic acid (P < 0.05) increased significantly during fermentation. The thiamin, riboflavin, niacin, vitamin B₆ and folic acid contents of tarhana dough were 4.80, 1.85, 7.68, 15.30 and 2.25 mg kg^?1 respectively at the beginning of fermentation and increased to 10.15, 5.15, 24.04, 19.35 and 6.10 mg kg^?1 respectively at the end of fermentation. Thiamin, riboflavin and folic acid contents were significantly affected (P < 0.01) by storage type and period, but niacin and vitamin B₆ contents were not affected (P > 0.05). The water‐soluble vitamin contents of tarhana stored wet were higher than those of tarhana stored dry. Drying resulted in a 24% reduction in riboflavin content and an 86% reduction in folic acid content. Copyright © 2007 Society of Chemical Industry     

TaqMan probe real-time polymerase chain reaction assay for the quantification of canine DNA in chicken nugget

This paper describes a short-amplicon-based TaqMan probe quantitative real-time PCR (qPCR) assay for the quantitative detection of canine meat in chicken nuggets, which are very popular across the world, including Malaysia. The assay targeted a 100-bp fragment of canine cytb gene using a canine-specific primer and TaqMan probe. Specificity against 10 different animals and plants species demonstrated threshold cycles (Ct) of 16.13 ± 0.12 to 16.25 ± 0.23 for canine DNA and negative results for the others in a 40-cycle reaction. The assay was tested for the quantification of up to 0.01% canine meat in deliberately spiked chicken nuggets with 99.7% PCR efficiency and 0.995 correlation coefficient. The analysis of the actual and qPCR predicted values showed a high recovery rate (from 87% ± 28% to 112% ± 19%) with a linear regression close to unity (R² = 0.999). Finally, samples of three halal-branded commercial chicken nuggets collected from different Malaysian outlets were screened for canine meat, but no contamination was demonstrated.     

Evaluation of the Effects of Cucumis sativus Seed Extract on Serum Lipids in Adult Hyperlipidemic Patients: A Randomized Double‐Blind Placebo‐Controlled Clinical Trial

Hyperlipidemia is associated with increased risk of atherosclerosis; therefore, control of this risk factor is very important in preventing atherosclerosis. Cucumber (Cucumis sativus) seed is used traditionally as a lipid‐lowering nutritional supplement. The aim of this study was to evaluate the effect of cucumber seed extract on serum lipid profile in adult patients with mild hyperlipidemia. In a randomized double‐blind placebo‐controlled clinical trial, hyperlipidemic patients with inclusion criteria were randomly and equally assigned to either Cucumis or placebo groups and used one medicinal or placebo capsule, respectively, once daily with food for 6 wk. Body mass index (BMI) as well as fasting serum levels of total cholesterol, triglycerides (TG), low‐density lipoprotein (LDL‐C), and high‐density lipoprotein (HDL‐C) were measured for all patients pre‐ and post‐intervention and finally the changes were compared between the groups. Twenty‐four patients in Cucumis group and 23 patients in placebo group completed the study. Cucumis seed extract resulted in significant reduction of total cholesterol (P = 0.016), LDL‐C (P < 0.001), TG (P < 0.001), and BMI (P < 0.001) as well as significant increase of HDL‐C (P = 0.012) compared to placebo. In conclusion, the consumption of C. sativus seed extract with daily dose of 500 mg results in desirable effects on serum lipid profile in adult hyperlipidemic patients. Therefore, cucumber seed could be considered as a food supplement for treatment of dyslipidemia.     

Determination of silver release from antibacterial finished cotton and polyester fabrics into water

Silver compounds have extensive use among the antimicrobial agents in textiles. Silver particles are released into the water during washing processes in particular and they are released from the textile in time due to use. In this work, silver ion release from cotton and polyester antimicrobial fabrics which are the most widely used textiles have been studied. Two well-known silver-based commercial agents and silver-doped calcium phosphate powder-based antibacterial finishing agent which was developed in our previous work were applied to the fabric samples. The release of silver from the fabric samples during washing and incubation was determined by ICP-OES. The effects of fabric composition, time and laundering process on the silver release were studied. It was found that significant amount of silver was released from textile fabrics during washing due to the mechanical forces exerted on the fabrics. The total released silver varied from 73.43 to 92.27% for cotton fabrics and 76.49 to 89.70% for PES fabrics after 20 washing cycles. Results also showed that calcium phosphate can reduce the amount of silver release significantly. It was also found that even a smaller quantity of nanosilver particles was sufficient for strong antibacterial activity.     

Short communication: Genetic parameters of individual fatty acids in milk of Canadian Holsteins

The objective of the present study was to estimate heritabilities of milk fatty acids (FA) and genetic and phenotypic correlations among milk FA and milk production traits in Canadian Holsteins. One morning milk sample was collected from each of 3,185 dairy cows between February and June 2010 from 52 commercial herds enrolled in Valacta (Ste-Anne-de-Bellevue, Quebec, Canada). Individual FA percentages (g/100 g of total FA) were determined for each sample by gas chromatography. After editing the data, 2,573 cows from 46 herds remained. Genetic parameters were estimated using multitrait animal models fitted under REML. The model included fixed effects of age at calving and stage of lactation each nested within parity and random effects of herd-year-season of calving, animal, and residual. The pedigree of animals with data was traced back 5 generations on both the male and female sides to account for relationships among animals. The estimates of heritability for individual FA ranged from 0.01 to 0.39, with standard errors ranging from 0.01 to 0.06. Generally, monounsaturated FA (MUFA) and saturated FA (SFA) showed higher heritability estimates than polyunsaturated FA (PUFA). Overall, SFA were negatively genetically correlated with MUFA and PUFA, whereas genetic correlations between MUFA and PUFA were positive. The SFA showed positive associations with fat yield and fat percentage, whereas unsaturated FA were negatively associated with fat yield and fat percentage. Bovine milk FA composition could be improved through genetic selection, and selection for MUFA or against SFA could alter the bovine milk fat profile in a desirable direction.     

Determination of sunset yellow (E110) in foodstuffs and pharmaceuticals after separation and preconcentration via solid‐phase extraction method

The two novel preconcentration and separation methods based on adsorption onto Amberlite XAD‐1180 and Amberlite XAD‐16 polymeric resins for spectrophotometric determination of sunset yellow dye were developed. The parameters, affecting the quantitative recovery, including pH, sample and eluent flow rates, eluent type, sample volume, were investigated and optimised. The interference effects of some cations, anions and widely used dye were also studied. At the optimum conditions, detection limits of the methods were found as 2.0 and 1.6 μg L^?1 for Amberlite XAD‐1180 and Amberlite XAD‐16 resins, respectively. Linear dynamic ranges of the methods were obtained in the range of 0.2–50.0 and 0.2–20.0 μg mL^?1 for Amberlite XAD‐1180 and Amberlite XAD‐16 resins, respectively. The relative standard deviations were below than 7% and 5% for Amberlite XAD‐1180 and Amberlite XAD‐16 resins, respectively. The determination of dye was performed at 483.0 nm using spectrophotometry. Validations of the methods were performed comparatively with determination of the sunset yellow content of some foodstuffs and pharmaceuticals.