Effect Of Various Concen Trayious Of Hydrogen Pereoxide On Chemical And Microbiogical Quality Of Raw Buffalo Milk
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Publisher: 2011 Dissertation note: Milk is a complex mixture of fat, proteins, carbohydrates, minerals, vitamins and other miscellaneous constituents dispersed in water. Milk production in flush season is much more than in the normal. Milk production and supply fluctuate through out the year and during winter it is surplus to its demand. Surplus milk is available in winter due to new calving, less consumption of milk by the consumer. In winter season ample amount of green fodder is available to the animals which in turn increase the milk production.
Milk and milk products being very delicate and perishable food require special handling prior to the consumption and further treatment. Pakistan due to its harsh climatic conditions people are using different methods, for the preservation of milk. They are using different chemicals, additives and antibiotics to enhance the keeping quality of milk. Present study was planned to investigate the various concentration of hydrogen peroxide or raw buffalo milk and its effect on chemical and microbiological quality of raw buffalo milk.
Raw buffalo milk samples were collected from Dairy Animal Training and Research Centre, University of Veterinary and Animal Sciences, Ravi campus Pattoki Fifty samples of raw buffalo milk (100ml each) were collected to studied the nutritional composition and microbiological quality of the milk after adding the hydrogen peroxide. The hydrogen peroxide of different concentration i.e. 0.025%, 0.05%, 0.075%and 0.1% were used in this study. There was no significant change in the result regarding various nutritional composition of raw buffalo milk after adding the various concentrations of hydrogen peroxide. There is a slight change in the lactose % during study of 48 h storage of milk at different temperature. Statistically the change which occurred in lactose during storage is significant whereas over all decrease in Solid Not Fat is non significant
Mean value of TPC of raw buffalo milk treated with different concentrations of hydrogen peroxide storage at the three different temperatures indicated that at 10° C TPC was very less as compared to control. TPC at 30° C after 48 h was 9.83x106.Which was very less as compared to TPC of control i.e. 1.195 x107.
The effect of H2O2 on the quality of the milk is negligible as compared to the losses suffered without it. The hydrogen peroxide definitely have its effect as a preservative.. The use of preservative in milk and dairy products are not new in the countries where ambient temperature remains quite high. Our study suggests that the concentration of hydrogen peroxide to be used for the preservation of raw milk is 0.05 % to 0.1 %
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Proteomic And Genomic Analysis Of Methicillin-Resistant Staphylococcus Aureus And Efficacy Of Indigenous Medicinal Plants Essential Oils
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Publisher: 2015 Dissertation note: A Cohort study (prospective and observational) was performed to study the prevalence of Methicillin resistant Staphylococcus aureus from the healthy individuals of community, hospitalized patients and associated health-care workers and indigenous plants essential oils were screened as new, improved & potent antibacterial/s against resistant strains of MRSA.
The method involved isolation and identification of MRSA from surgical wounds of hospitalized patients & associated health care workers in a tertiary care hospital in Lahore and healthy volunteers from the community. Plant essentials oils & extracts were evaluated for their antibacterial activity against selected MRSA isolates. Oils were recovered by steam distillation using an all-glass distillation assembly. Then in vitro sensitivity and MICs of plant essential oils were determined using vancomycin and linezolid as commercial standards. The essential oils were screened further for the active constituents by column chromatography using various solvents and identification of compounds were performed by GC/MS analysis and the fractions which showed prompt results were evaluated for antimicrobial activity against the MRSA isolates in quest to find new therapeutic options. Finally effective essential oils and their active fractions were studied for their toxicity using in vitro Genotoxic assays such as Ames and Comet assays. To further ensure their beneficial effects antimutagenic effect of the essential oils were also studied.
Prevalence of S. aureus among patients was 52.9%, in HCWs 86.5% and in community 74% with an overall percentage of 72.6%. Among S. aureus those declared as MRSA were 91.8% from patients, 50.6% from HCWs and 59.5% from community with an overall percentage of 62.2% MRSA. Among the isolated MRSA overall 90.6% were Coagulase positive and 75.2% were biofilm positive.
The pattern of MRSA resistance against current antibiotics have shown an overall increase in the resistance with maximum shown for lincomycin followed by tetracycline, ampicillin, fusidic acid, amoxicillin and piperacillin with tazobactam. The most effective options among current regime were tigecyclin, amikacin and meropenem showing an overall least resistance. Resistance against linezolid was observed with an overall percentage of 25.6 % and vancomycin 33.3% by disc diffusion method.
The MRSA isolates resistant to one or more groups of antibiotics were declared as MDRs. Among patients and health-care workers all were declared as MDRs where as in community 93.1% isolates were MDRs.
Upon Protein profiling using whole cell proteins 44 bands of the polypeptides were produced with molecular size 10-200kDa from the three sampling groups and were categorized into 5 clusters showing an overall significance correlation with each other explaining an interesting fact that all these strains were interlinked establishing the fact of flow of hospital acquired MRSA in the community and vice versa. This analysis also gave an insight in explaining the fact of horizontal transmission of infection within the hospital.
Keeping in view the raise in resistance among current available antibiotics indigenous medicinal plants essential oils were screened for active constituents exhibiting anti-bacterial effects against MRSA isolates.
Maximum yield was obtained from Carum copticum followed by Cuminum cyminum and minimum yield was obtained in case of Zingiber officinale. Upon qualitative analysis of all five essential oils Carum copticum essential oil showed zones of inhibition greater than the standards vancomycin and linezolid followed Cuminum cyminum and Zingiber officinale in all three
sampling groups. Anethum sowa and Myristica fragrans essential oils showed no activity against MRSA.
Minimum inhibitory concentration of the three essential oils determined by micro broth dilution method indicated that Carum copticum showed least value in all three types of MRSA isolates followed by Zingiber officinale and Cuminum cyminum.
Effective essential oils were further fractioned using silica gel gravity columns. All the fractions obtained were screened for the anti-bacterial activity against all three types of MRSA isolates. Only fraction F1 of Carum copticum showed activity greater than pure essential oil and the two commercial standards of vancomycin and linezolid.
For the identification of active constituents GC/MS analysis was performed on all three essential oils and their respective fractions. In case of fraction F1 the most dominant constituents were Carvacrol, p-Cymene, Ʈ-Terpinene and Apiol. In other two plants none of the fractions were effective. Therefore it was concluded to use pure essential oils in case of Zingiber officinale and Cuminum cyminum rather than their individual fractions and incase of Carum copticum Fraction F1 has shown superior activity.
Finally these essential oils were tested for possible mutagenic effect using bacterial reversion mutation assay and Comet assay. No mutagenic effects were observed at MIC and above doses. These effective essential oils were also evaluated for possible antimutagenic effect. Both Carum copticum and Zingiber officinale essential oils showed strong antimutagenic effects and weak antimutagenic effect by Cuminum cyminum. Upon analysis of nuclear damage none of the plants essential oils and fraction F1 of Carum copticum showed genotoxic effects and indicated to be safe. Thus from the study it was concluded that Carum copticum essential oil and its fraction F1 were the most effective to be further investigated as an alternative treatment for MRSA infections.
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Comparative Quality Evaluation Of Raw And Pasteurized Milk
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Publisher: 2016 Dissertation note: This particular project was designed to evaluate the overall quality of raw and pasteurized milk available at different areas of Lahore. The parameter which was checked includes microbiological analysis, adulterants, physicochemical properties and the effect of temperature on vitamin C in milk samples. Raw samples were collected from ten different towns of Lahore, whereas pasteurized milk samples belong to ten different brands. Ten samples were collected under control conditions from animals in sterilized containers.
For microbiological analysis four parameters were selected including total plate count (TPC), total coliform count (TCC), total psychrotrophic count (TPSC) and total yeast and mold count (TYMC) whereas, different adulterants like adulteration test was done such as urea, starch, hydrogen peroxide, detergent or soap, sorbitol, quaternary ammonium compound, boric acid, cane sugar, sodium chloride, formalin and hypochlorite were checked by using the milk adulteration kit in QOL. Milk contains casein and whey proteins. Whey protein being added in the milk to increase its density which is considers being an adulterant. In this project whey protein was estimated in all milk samples by titration method. Physicochemical characteristics of milk are an important parameter to judge the quality of milk. These physicochemical properties include fat%, SNF%, density kg/m3, lactose%, solid/ash, protein% and pH. Physicochemical properties were evaluated mechanically by Milkoscan. Heat treatment is an important method to reduce the microbiological contamination of milk. These treatments may include pasteurization and UHT etc. During the heat treatment some of the micronutrients may deteriorate thus compromising the quality of milk. Vitamin C is among those heat labile micronutrients. Vitamin C was checked quantitatively in market and self-collected samples by using titration method.
It was concluded that total plate count TPC, TCC, TPSC and TYMC of raw milk samples were above the standard value indicating the poor quality of the milk. As far as the pasteurized milk samples were concerned ninety percent of the samples showing higher values for TCC, TPSC and TYMC. Total plate counts of all self-collected raw milk from a healthy animal were found within the standard value. Counts were in range of 3.8x 103 – 8.9x103 CFU/mL of all milk samples. TPC of all self-collected raw milk from a healthy animal were found within the standard TCC were found within permissible value (102 CFU/mL .TPSC were negative for all milk samples. TYMC were in range of 2.6x101 -7.2x101 CFU/mL. Among milk samples (n=10), three samples (30%) were positive for TYMC were while remaining samples (70%) were negative and showed no growth.
Physicochemical factor show that 50 percent of raw milk have low nutritional value as compared to the standards which are buffalo and cow milk contains 7.6, 4.5% fat, 3.8, 3.8 % protein, 5.1, 4.9% lactose, 0.78, 0.72% ash and 17.0, 13.9% total solid respectively. In raw milk mean of fat (%), solid not fat (%), lactose (%), Solid/ash (0%), protein(%) and pH were 4.50±0.03, 7.915±0.06, 23.05±0.055, 3.893±0.06, 3.85±0.05, and6.9±0.0.02 respectively. In pasteurized milk mean value for fat, SNF, lactose, ash, protein and pH were 3.48 ±0.13, 7.24±0.10, 3.60±0.05,0.5 ±0.06, 2.82±0.05, 7.2±0.20 respectively. Pasteurized milk is good for consumption.
Different adulterant such as urea, starch, hydrogen peroxide, Sorbitol, QAC, Boric acid, Cane sugar, NaCl, Carbonate, Formalin, hypochlorite, whey protein, Added water and soap /detergents were evaluated in all milk samples. Among these adulterant water (66%) was found in majority of milk samples, followed by whey protein (15%), starch (13%), (10%) NaCl and
(8%) cane sugar were detected in raw milk samples. n Pasteurized milk samples only added water (49%) and whey protein (31%) was detected.
Among the raw milk samples the maximum and minimum concentration of vitamin C was observed 0.33±0.02 and 3.33 ±0.02 mg/100ml and for pasteurized milk maximum and minimum concentration of vitamin C was observed 2.54mg/100ml and 0.32 ±0.02 mg/100ml respectively. In self- collected samples the minimum and maximum concentration of vitamin C was observed 5.25±0.02 and 8.34 ±0.04 mg/100ml respectively and after pasteurization in laboratory minimum and maximum concentration of vitamin C was observed 3.48±0.04 and 5.83 ±0.02 mg/100ml respectively. These observations had showed that pasteurization treatment decreased Vitamin C quantity.
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Pathogenesis Of Aflatoxin B1 In Quails Under Experimental Conditions And Detoxification By Biological And Chemical Means
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Publisher: 2016 Dissertation note: Secondary metabolites of certain fungi produce toxins under favorable conditions especially while growing on different food grains. Mycotoxins are among major threats to growing poultry industry and human beings. Aflatoxins are closely related, biologically active fungal metabolites and commonly produced by Aspergillus species.
A research was carried out to evaluate the ability of Aspergillus flavus for Aflatoxin B1 production using rice, wheat and maize as substrates. Lethal effects on growth performance parameters, hematological and histopathological of graded doses of aflatoxin B1 in quails under experimental conditions were observed. Effect of Aflatoxin B1 on humoral immune response to Newcastle Disease virus vaccine in quails were determined. Biological detoxification of Aflatoxin B1 by Saccharomyces servisiae was evaluated in quails. Comparative evaluations of different commercially available toxin binders were checked. All these experiments were carried out till the six weeks (42 days).
Aspergillus flavus was identified on the basis of macroscopic and microscopic characteristics. Rice, wheat and maize grains was used as substrate to check the level of Aflatoxin B1 produced by inoculating an aqueous suspension of 106 spores/ml. Aflatoxin B1 checked by Thin Layer Chromatography (TLC) and quantified by High Performance Liquid Chromatography (HPLC).
Quails were reared under standard management conditions in five groups (A, B, C, D and E) having sixty each. Each group was further divided in two independent units. Diets offered to groups were control (without toxins), 0.25, 0.50, 1 and 2 mg Aflatoxin B1/kg feed. One unit of
each group was vaccinated with Newcastle Disease Virus (NDV) vaccine while other was not and studied the lethal effects on growth performance, blood parameters, immune response and histopathology of vital organs. At the end of the experiment, it was found that the deleterious effects of Aflatoxin B1 were dose and duration dependent. As the level of the toxin was increased, the lethal effects were prominent. The growth performance parameters including gain in body weight, feed intake and feed conversion ratio was adversely affected at high doses. The body weight gain was significantly reduced in Aflatoxin B1 treated groups as compared to control group. Similarly feed intake and feed conversion ratio were significantly different from the control group. The hematological studies exhibited that aflatoxin B1 significantly reduced the hemoglobin, packed cell volume and total leukocyte count whereas the erythrocyte sedimentation rate was significantly increased as compared to control group. The immune response against NDV vaccine was adversely effected in Aflatoxin B1 treated groups and values of Antibody titer in AFB1 were significantly low as compared to group A( control) In the second experiment, Saccharomyces cervisae (SC) dried powder was mixed in basal quail diet having 0.5mg Aflatoxin B1 for all experimental groups and control was without toxins. SC was added at levels of 0.5 gm, 1.0 gm and 2.0 gm /kg of feed. It was recorded that Saccharomyces cervisae (yeast) have the potential to remove the deleterious effects of Aflatoxin B1. Yeast effectively detoxified the Aflatoxin B1. The results recorded of growth performance and other parameters were non-significantly different from the control group. Chemical detoxification of Aflatoxin B1 was evaluated in quails using commercially available toxin binders. Toxin binders used were activated charcoal, kaoline, Myco AD and selenium plus vitamin E and mixed in basal quail diet having 0.5mg Aflatoxin B1 for all experimental groups and control was without toxins. The Myco AD and selenium plus vitamin E showed the highest detoxification potential as compared
to other chemical toxin binders. Groups E and F showed the results of growth performance, hematological, immune response and histopathological were non-significantly different from the control group (A). Kaolin was moderately detoxifying the toxin.
Presence of aflatoxin B1 in soft tissues was checked by TLC and quantified using HPLC. The liver exhibited the residues of Aflatoxin B1 at high doses of toxin. Group D and E rearing on feeds having 1mg AFB1 /Kg feed and 2mg AFB1 /Kg feed of toxin showed the residues of AFB1 in liver and kidney.
Statistical means for growth performance parameters, hematological, immune response and histopathological scores in each subunit of quails were analyzed by applying one way ANOVA and Duncans‟s Multiple Range (DMR) test at 95% probability. Aflatoxin B1 is lethal and lowers the performance of birds. The lethal effects can be detoxified by biological and chemical means to lower the economic losses to poultry industry. It can be concluded that biological detoxification is preferably better as compared to chemical detoxification.
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