Graphical abstract

In this study, we have investigated the effect of adding zinc chloride (ZnCl2) on polycaprolactone (PCL) before and after electrospinning. The rheological properties and conductivity of ZnCl2/PCL solutions were measured prior to the electrospinning process. The resultant electrospun mats were characterized by SEM, contact angle, FTIR, XRD, mechanical properties, as well as its antibacterial and stem cell proliferation assessment were tested. It was found that the fibers became finer by increasing the zinc salt content. Moreover, stability increased slightly up to 5% Zn-PCL and also the hydrophilicity has been enhanced by 52%. By adding ZnCl2, the degradation rate and mechanical properties were significantly increased. Also, the resultant mats have shown antibacterial properties against S. aureus than E. coli. From the stem cells proliferation study, it can be observed that by increasing ZnCl2, the stem cells proliferation was significantly increased. Grooved multichannel nerve conduits were successfully fabricated by rolling the electrospun mats produced on corn husks which has shown better cell alignment and attachment. Hence, adding zinc chloride is a facile biocompatible enhancement to polycaprolactone nanofibers to be used in nerve regeneration.

No abstract

The present study was carried out to evaluate the antimicrobial and antioxidant effects of black tea extract (BTE), green tea extract (GTE) and carob extract (CRE) in buffalo butter during storage at 4±1ºC for 12 weeks and compare to synthetic phenolic compound butylated hydroxytoluene, (BHT). The antibacterial effect and minimal inhibitory concentration (MIC) of extract against Listeria monocytogenes were studied. The effectiveness of these extracts (0.025 -0.05%) in butter made from pasteurized cream were evaluated by incubating (10 5 cfu/g) of Listeria monocytogenes. The GTE had completely inhibited (P≤0.05) the viability growth of Listeria monocytogenes during storage at 4±1ºC (10 -12 weeks) . During storage of butter made from unpasteurized cream, the population of lipolytic bacteria and mould&yeast markedly reduced (P≤0.05) by addition GTE (0.025 -0.05%) compared to other treatments. Also, BHT (0.025%) and GTE had similar inhibitory effect on Staph. aureus. E. coli and total counts. The BTE and GTE had a most antioxidant effect on decreasing the acid value (AV), peroxide value (PV) and thiobarbituric acid value (TBA). While CRE had less effect. Organoleptically, butter with added BTE, GTE and CRE gained the highest acceptance until 8 weeks compared with BHT treatment and control sample. This research has demonstrated that the use of BTE and GTE as a natural antimicrobial and antioxidant is a promising means to provide additional safety and improve the quality of buffalo butter during storage.

No abstract

The present study was carried out to evaluate the antimicrobial and antioxidant effects of black tea extract (BTE), green tea extract (GTE) and carob extract (CRE) in buffalo butter during storage at 4±1ºC for 12 weeks and compare to synthetic phenolic compound butylated hydroxytoluene, (BHT). The antibacterial effect and minimal inhibitory concentration (MIC) of extract against Listeria monocytogenes were studied. The effectiveness of these extracts (0.025 -0.05%) in butter made from pasteurized cream were evaluated by incubating (10 5 cfu/g) of Listeria monocytogenes. The GTE had completely inhibited (P≤0.05) the viability growth of Listeria monocytogenes during storage at 4±1ºC (10 -12 weeks) . During storage of butter made from unpasteurized cream, the population of lipolytic bacteria and mould&yeast markedly reduced (P≤0.05) by addition GTE (0.025 -0.05%) compared to other treatments. Also, BHT (0.025%) and GTE had similar inhibitory effect on Staph. aureus. E. coli and total counts. The BTE and GTE had a most antioxidant effect on decreasing the acid value (AV), peroxide value (PV) and thiobarbituric acid value (TBA). While CRE had less effect. Organoleptically, butter with added BTE, GTE and CRE gained the highest acceptance until 8 weeks compared with BHT treatment and control sample. This research has demonstrated that the use of BTE and GTE as a natural antimicrobial and antioxidant is a promising means to provide additional safety and improve the quality of buffalo butter during storage.

Thirty burger samples were randomly collected from food shops super marks in microbiologically investigated for the presence of some pathogenic microorganisms including Escherichia coli 0157:H7, Salmonella typhimurium, aureus and Bacillus cereus were detected in 60% of the examined samples with an average counts of 14x10 5.1x10 2 cfu/g. however, Escherichia coli 50 and 40% of the examined samples, with an average counts of 12x10isolates of pathogenic bacteria including 20 isolates each of Escherichia coli 0157:H7, following the biochemical identification tests (Bergey's Manual). Only 56 out of the testes 85 isolates were confirmed as pathogenic species using Hi identification kits and latex test kits. The obtained results indicated that these foods may pose a source of infection to the consumer. Measures to control the quality of the raw material, environmental and hygienic conditions during preparation and serving s

Microbiological assay of 150 samples of dairy products for the incidence of Coliforms, E. coli, E. coli 0157:H7 and non-0157 E.coli, show the recovery of the Coliforms and E.coli from the tested products with different incidence percentage. Strains of E. coli 0157:H7 and non-0157 E .coli were recovered from 9 (6%) and 13(8.6%) of the total samples, respectively. The behaviour of these isolates were tested when exposing to low pH, salt, low holding temperature and heat treatment. The results indicate obvious survival of E. coli 0157:H7 and non-0157serotype with pH as low as 3.8 pH for 5 days. Also, survival or even multiplication in TSB containing <6% salt. Moreover, the strains remained viable at low holding temperature (5 o C). So, the product which contaminated with this pathogens remain hazardous even under such stress condition. Decimal reduction times (D-values) of cells suspended in saline solution, TSB medium, reconctituted dry milk and chocolate milk were determined. The greatest survival as evidenced by highest D and Z values occurred with chocolate milk. Product composition and type of strain affected the heat lethality rates.