Abstract Prodigiosin is a red pigment produced by Serratia marcescens strain. Bacterial prodigiosin and its synthetic derivatives are efficacious antioxidants and proapoptotic agents. This study illustrates a new approach for use of prodigiosin conjugated silver nanoparticles (PG-AgNP2) against cadmium chloride (CdCl2) induced neurotoxicity in rats. Rats were (ip) injected with Cd (6.5 mg/kg) for 7 days with or without PG-AgNP2 (3 mg/kg). The concentration of Cd, DA, NE, 5-HT, amino acids, NO, MDA, SOD, GSH, catalase, TNF-α, IL-6, Bax, Bcl2 and Caspase-3. The Cd-intoxicated group showed a significant increase in Cd concentration in brain tissue, in addition, to an increase in MDA and NO and a decrease in the content of neurotransmitters (DA, NE, and 5-HT), inhibitory amino acids, and level of all studied antioxidant enzymes. PG-AgNP2 treatment, significantly reduced Cd-induced brain tissue injury as indicated by increased antioxidant molecules, neurotransmitters (DA, NE, and 5-HT), and inhibitory amino acids accompanied by lower oxidative stress indices (MDA and NO) and excitatory amino acids in brain tissue. PG-AgNP2 decreased inflammatory mediators including pro-inflammatory cytokines and prevented the development of apoptosis in the brain tissue. Our findings suggest that PG-AgNP2 can act as a therapeutic agent against neuronal impairments associated with Cd exposure.

Abstract We studied the effect of the calyx of cape gooseberry nanoparticles manufactured by a novel technique. There are several methods, such as jet mill, spray freezing, supercritical anti-solvent technique (SAS), and high-pressure homogenization, available for the production of drug micro/nanoparticles to improve drug solubility. Anti-solvent precipitation is also used to prepare micro- and nanosized particles to explain their effects on different foodborne pathogens, contaminated bacteria, and some fungi. Results indicated that nanoparticles of the cape gooseberry calyx contained higher antioxidant activity than that found in the normal calyx, seed, and juice. While studying the effect of cape gooseberry calyx nanoparticles on microorganisms, it was found that the zone of inhibition was highly positive against Bacillus cereus, B. subtilis, Staphylococcus aureus, Clostridium perfringens, and Salmonella typhimurium compared to that of the normal cape gooseberry calyx. All species of molds, including Mucor sp., Aspergillus niger, Penicillium sp., and Alternaria sp., and yeasts like Saccharomyces cerevisiae and Rhodotorula glutinis were affected by nanoparticles of the cape gooseberry calyx compared to those of the normal calyx.

Abstract Nisin and reuterin are used in processed foods as preservatives. They are considered to be potential sources of natural antibiotics for the treatment of food contaminated by antibiotic-resistant bacteria, such as methicillin-resistantStaphylococcus aureus. We try to compare the best effect of both nisin and reuterin on the growth of methicillin-resistant S. aureus (MRSA) and S. aureus ATCC 25923. The results indicated that nisin at different concentrations inhibited the growth of methicillin-resistant S. aureus after 4 h, whereas after 12 and 24 h, the bacteria have regrown and reactivated. S. aureus ATCC 25923 was not affected by nisin concentration and has continuously grew at all times. Reuterin at different concentrations gradually inhibited the growth of methicillin-resistant S. aureus and S. aureus ATCC 25923 and declined after 12 h for both. Therefore, it can be deduced that nisin alone exerts a bacteriostatic effect on methicillin-resistant S. aureus but not on S. aureus ATCC 25923. Reuterin is considered as bactericidal effect on both microorganisms. The combination of nisin at a concentration of 25.6 and reuterin at a concentration of 5.2 mg/mL exerted a bactericidal effect on both microorganisms. By mixing nisin with reuterin, it can be more active against both microorganisms.

Abstract Seventy eight yeasts were isolated from different foodstuffs. Out of the seventy eight isolates four yeast species namely C. parapsilosis Q3, C. solani F8, C. versatilis J3 and K. jensenii H1 were selected to study their biological activity. The four strains termed as killer yeast by observing its activity against microorganisms. Killer yeasts secrete proteinaceous killer toxins lethal effect against some of Gram positive and negative bacteria, molds and yeasts. The antagonistic effect of the four killer yeast strains on the growth of different microorganisms recorded as zone of inhibition (mm), demonstrated that C. versatilis J3 was an active stains against majority test microorganisms. Consumed sugar determined for the four strains and showed that C. versatilis J3 and C. parapsilosis Q3 reached to its maximum on the 12 hours of incubation both yeast consumed 97.5 and 95% of initial sugar (sugar utilization efficiency) while both of C. solani F8 and K. jensenii H1 sugar utilization efficiency was recorded on the 24 hours being 99.65 and 99.30%, respectively.

Abstract The antimicrobial activities of certain spices and herbs are well-documented. Herbs and spices are often exposed to bacterial contamination, spore-forming bacteria in particular. The spores introduced during the production process result in a contamination that causes food alteration during storage. The aim of this study was to isolate spore-forming bacteria from commercially available spices and herbs, such as ginger, cinnamon, black pepper, curcumin, saffron, and clove. The API 50 CHB/E medium was used to identify different genera of spore-forming bacteria isolated from samples. We found that these belonged to the genus Bacillus, such as Bacillus cereus, which was isolated from cinnamon, and Bacillus subtilis, and isolated from curcumin and black pepper. The third species belonged to the genus Brevibacillus, Brevibacillus laterosporus, which was isolated from ginger. The D-values (decimal reduction) of each bacterium were determined at 80, 85, 90, 95, and 100 °C. The Z-value was determined for each bacterium. The whole-cell protein profiles of the identified bacteria were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Since spore-forming bacterial contamination of herbs and spices can occur during their harvest, exsiccation, or through cross-contamination during packaging, we propose different methods for spore elimination.

Abstract The deterioration of fish by microorganisms is very quickly, because it’s a highly perishable foods and short shelf life, for this reason the handling and stored condition very important to slow down and extend the shelf life and its quality. There are a number of strategies used as traditional methods to extend the shelf life of fishes included: chilling, freezing, icing, drying, smoking and salting. From the innovative processing technologies using of icing system with organic acids is considered to be a preservative method and delaying the changing in the fish and able to guarantee the quality with extension of their shelf-life. The present study provides the addition of organic acid as lactic acid (0.1%), propylene glycol (7%), potassium sorbate (1000 ppm) and mixture of potassium sorbate (1000 ppm) + sodium benzoate (0.2%) to fresh water and dipping the mullet fish in it then preserved in fresh water crushed ice medium containing the same concentration of organic acids. Different parameters were determined to limit the quality and safety of mullet during storage periods as total volatile nitrogen base, trimethylamine, thiobarbituric acid-value, refractive index of the muscle fluids, electrical resistance of the fish muscles, organoleptic evaluations and in addition to total viable count of bacteria and psychrophilic bacteria. The mixture of potassium sorbate and sodium benzoate using icing system method extended the shelf life of mullet fish up to 17-19 days of storage period in comparison with control and other organic acids.

Abstract Citrox has natural antibacterial effect against many foodborne pathogens and contaminated bacteria. It mainly contains citric acid, ascorbic acid, and malic acid. We studied the antimicrobial effects of citrox solution (1% and 2%) on the total viable count of methicillin-resistant Staphylococcus aureus (MRSA) on chicken meat fillet. The samples were treated with 106 CFU/g of meat, vacuum-packed (VP), and 4 °C for 3, 6, 9, 12, 15, 18, 21 days. We have also studied the effect of citrox on the total volatile basic nitrogen (TVBN) content and pH changes during the storage periods. The results revealed that citrox inhibited the growth of methicillin-resistant S. aureus (MRSA), in the chicken fillet. The total viable count of MRSA gradually decreased in all treated samples that were stored at 4 °C about 2 log cycle than Chicken-Staph groups after 3, 6, 9, and 12 days and about 1 log cycle than Chicken-Salt group after 3, 6, and 9 days of storage. Total volatile base nitrogen (TVB-N) were observed to be reduced in Chicken- Citrox-treated samples stored at 4 °C than Chicken-Staph, and Chicken-Salt treated samples. The results indicated that citrox is effective to reduce the total count of S. aureus (MRSA) in the first three days of storage by a reduction in the number of bacteria 1 log cycle.