HEAVY METAL BIOSORPTION BY SOME BACTERIAL SPECIES ISOLATED FROM DRINKING WATER AT DIFFERENT SITES IN SHARQIA GOVERNORATE

The nine most frequent bacterial strains out of 127 were isolated form ten drinking water samples collected from tap water and bottled water in sharqia governorate. The nine isolates were purified and examined for their resistance to increasing concentrations of two heavy metal ions, lead (Pb+2) and iron (Fe+3). Four stains out of the nine isolates encoded I, II, IV, and VIII showed the highest efficiency of both Pb+2 and Fe +3 uptake from nutrient broth media containing 100 ppm of the heavy metal ions. The four bacteria were preliminary identified and then confirmed by the Biolog examination as Corynebacterium jeikeium, Pseudomonas putida biotype A, Acinetobacter calcoaceticus and Acidovorax delafieldii. The increased concentrations of Pb+2 ions (from 100 to 500 ppm) in nutrient broth media had deleterious effect on the process of heavy metal uptake (biosorption) by all the four selected isolates. Whereas percentage of Pb+2 uptake decreased from 42.9 to 24%; from 72.6 to 42%, from 78.9 to 37% and from 68.8 to 45%, for the four selected isolates, respectively. Meanwhile there was slight decrease change in Fe+3 uptakes percentage accompanying the increase in heavy metal ion concentration. Optimization of the cultural conditions releaved maximum uptake op pb+2 and Fe+3 by the four tested strains in presence of 100 ppm heavy metal concentration when incubated at 25oC except for Acinetobacter calcoaceticus at 35oC in case of Pb+2 uptake, when pH, was adjusted at 5 under static conditions. Upon addition of 50 ppm Cu+2 ions to broth media supplemented with 100 ppm Pb+2 ions, the percentage of metal biosorption by the four tested isolated decreased between 41.11% and 48.45% according to type of strain. Similarly presence of Cu+2 ions caused decrease in Fe+2 uptake by the four isolates ranging between 29.14-45.1%. Percentage of Pb+2 ions uptake by the tested bacteria sharply decreased when a sterile tap water sample was used as natural medium for cell-metal contact. The percentage of uptake inhibition of Pb+2 ranged between 57-65.23% and between 75.1-84.27% for Fe+3 ions. Cell hydrolysate of three tested bacteria appeared to be free from plasmid DNA proving that the genetic character of heavy metal resistance is plasmidless and related to chromosmal DNA in case of Cory. jeikeium, P. putida and A. delafieldii. On the other hand, Acinet. Calcoaceticus contained plasmid of size 23.130 kb. Examining Acientobacter calcoaceticus using transmission electron microscope revealed the accumulation of Pb+2 ions on bacterial cell surface and the intracellular absorption of Fe+3 ions

PENGARUH MEDIA KOMUNIKASI INTERNAL TERHADAP IKLIM KOMUNIKASI PERUSAHAAN (STUDI KASUS : BULLETIN REDBUZZ! PT. INDONESIA AIRASIA PERIODE FEBRUARI - MEI 2013)

PENGARUH MEDIA KOMUNIKASI INTERNAL TERHADAP IKLIM KOMUNIKASI PERUSAHAAN (STUDI KASUS : BULLETIN REDBUZZ! PT. INDONESIA AIRASIA PERIODE FEBRUARI - MEI 2013)

Safety of frozen liver for human consumption

The objective of this study was to ensure and evaluate the safety of imported frozen beef liver traded in supermarkets of Kafr El-Sheikh Governorate, Egypt, through detection of Salmonella typhimurium, Salmonella enteritidies, Escherichia coli O157:H7, antibiotic residues, and aflatoxin B1 residue. Fifty samples of imported frozen liver were randomly collected from different shops at Kafr El-Sheikh Governorate for isolation of S. typhimurium, S. enteritidies, and E. coli O157:H7. The results revealed that for both microorganisms 4% of the examined samples presumed to contain Salmonella and E. coli O157:H7 organisms, according to the colonial character on Harlequin Salmonella ABC agar media and Harlequin SMAC-BCIG agar media. According to biochemical and serological identifications, both organisms could not be detected in the examined samples. A total of 29 (58%) samples were positive for antibiotic residues, using the Premi test (a broad-spectrum screening test for the detection of antibiotic residues in meat) at or below the maximum residue limits. In addition, aflatoxin B1 was detected in one (2%) samples with a concentration of 1.1 μg/kg. The results reflect that there was good hygiene practice for handling and preparation of frozen liver while selling to consumers. However, a high percentage of antibiotic residues reflect ignorance of withdrawal time before slaughtering of animals as well as misuse of antibiotics in veterinary fields. Furthermore, aflatoxin B1 residue was detected in examined frozen liver samples at a concentration below the maximum residual level, which is not enough to cause threat to humans, but it is enough to cause problem if it is eaten regularly reflect contamination of animal feed with aflatoxins

Thymol alleviates imidacloprid-induced testicular toxicity by modulating oxidative stress and expression of steroidogenesis and apoptosis-related genes in adult male rats

The present work was designed to assess the potential ameliorative effect of thymol on the testicular toxicity caused by imidacloprid (IMI) in adult male rats. Forty adult male rats were allocated into four groups; control group was given corn oil, thymol-treated group (30 mg/kg b.wt), IMI-treated group (22.5 mg/kg b.wt), and IMI + thymol-treated group. All administrations were done by gavage every day for duration of 56 days. As a result, the IMI exposure caused a significant decline in the body weight change, reproductive organ weights, sperm functional parameters, and serum level of testosterone, widespread histological alterations, and apoptosis in the testis. Additionally, the IMI-treated rats exhibited a remarkable increment in the serum levels of follicle stimulating hormone and luteinizing hormone. Also, IMI induced testicular oxidative stress, as indicated by elevated malondialdehyde (MDA) levels and a marked decline in the activity of antioxidant enzymes and reduced glutathione (GSH), and total antioxidant capacity (TAC) levels. Moreover, IMI treatment significantly downregulated the mRNA expression of steroidogenic genes and proliferating cell nuclear antigen (PCNA) immunoexpression in the testicular tissue. However, thymol co-administration significantly mitigated the IMI-induced toxic effects. Our findings suggested that IMI acts as a male reproductive toxicant in rats and thymol could be a potential therapeutic option for IMI reprotoxic impacts

Can Dietary Phytogenic Mixture Improve Performance for Growth, Digestive Enzyme Activity, Blood Parameters, and Antioxidant and Related Gene Expressions of Nile Tilapia, Oreochromis niloticus?

The form of dietary phytogenic inclusion and its physiological causal mechanisms for growth promotion and immune stimulation in fish remain unknown. The study examined the effects of dietary phytogenic mixture extracted from lemon (Citrus limon), onion (Allium cepa), and garlic (Allium sativum) (LOG) on Nile tilapia performance, digestive enzymes, haemato-biochemical indices, oxidative stress, and associated gene expression for 70 days. In this experiment, diets were supplemented with 0, 10, 20, and 30 ml LOG kg−1 in isonitrogenous and isoenergetic diets and fed to tilapia with an average initial body weight (4.23 ± 0.09 g). Compared to the control diet, the dietary LOG at 20 ml kg−1 elicited the highest final body weight (FBW, 35.50 g fish−1), weight gain (WG, 31.2 g fish−1), specific growth rate (SGR, 3.02%, day fish−1), and survival rate (99.33%). Significant quadratic differences in chymotrypsin, trypsin, amylase, and lipase were shown with increasing LOG supplementation. There was a quadratic response in hematology parameters of fish with increasing LOG levels. Significant linear decreases in ALT, AST, cholesterol, and triglyceride were shown with the increased LOG inclusion in the diets. A polynomial correlation in total protein, albumin, and globulin was found under different inclusion levels of LOG while significant quadratic increases in SOD, CAT, and Gpx and significant quadratic decrease in MDA was found with increasing LOG supplementation. The IGM-2, SOD, and CAT gene expressions were quadratically improved; the highest relative expression was obtained by fish received 20 ml LOG kg−1 diet. Growth hormone gene expression was quadratically modulated in the liver and pituitary of fish fed diverse doses of dietary LOG compared with the control. The phytogenic of LOG at 20 ml kg−1 elicited the best tilapia performance and hematological indices, increased antioxidant and digestive enzyme activities, and gene expressions of growth, immunoglobulin and superoxide dismutase