Applied Biology and Biochemistry Publications

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Aflatoxin Carryover during Large Scale Peanut Butter Production.
(Scientific Research, 2011-04) Siwela, Andrew H.; Mukaro, Kudzayishe J.; Nziramasanga, Nozipho
Peanut butter was monitored for aflatoxin contamination at different stages during its large-scale production starting from raw shelled peanuts up to the final product. Twenty five samples, weighing 2 kg each, were taken from each of the following stages: roasting at 160°C, blanching/de-skinning and grinding. The sub-samples were ground, thoroughly mixed and further reduced by the quartering technique until a 1 kg sub-sample was obtained. This was then analyzed for aflatoxins using reverse phase HPLC incorporating pre-column trifluoroacetic acid derivatization. The results showed a total aflatoxin percentage reduction of 51% after roasting, 27% after blanching/de-skinning followed by a further 11% after grinding to make peanut butter. This meant that there was a cumulative total reduction of 89% of aflatoxin concentration during the production process of peanut butter. These results show that there is a significant reduction of aflatoxin levels at the roasting and blanching stages in the process of producing peanut butter.
Aflatoxin Contamination of Stored Groundnuts in Zimbabwe.
(ICRISA T (International Crops Research Institute for the Semi-Arid Tropics)., 1989) Siwela, Andrew H.; Caley, A.D.
Aflatoxins were analyzed in groundnuts stored for either local or export sales in the period 1982/83 to 1986/87. Four hundred and forty-one samples of seven groundnut varieties were collected for analysis. Sixty-eight percent of the samples had total concentrations of aIlatoxin BJ and OJ of up to 25 JIg kg-J. In the 1986/87 groundnut crop, the Flamingo and Makulu Red varieties, which constitute the bulk of export sales, had up to 25 JIgkg-J aIlatoxin BJin 79%of the samples, plus aIlatoxin OJ in 67% of the samples. Overall, the Egret variety was the most susceptible to aIlatoxin contamination during this period.
Alteration of some Hepatic Enzyme Activities by Gastrointestinal Helminth Parasites in Domesticated Ostritches.
(Society of Education, 2013-05-05) Siwela, Andrew H.; Motsi, Leonah R.; Dube, S.
Using the conventional methods for parasitological examinations of the salt floatation and direct smear, ten ostriches infected with internal parasites were identified. Ten birds that were without internal parasites were used as the controls. The metabolizing enzymes glutathione peroxidase (GPX), DT -diaphorase (DTD) and succinate dehydrogenase (SDH) were assayed accordingly using liver samples from the control and infected birds. Malondialdehyde (MDA), a marker of lipid peroxdation, was also assayed. Results showed that cestode eggs occurred at twice the amount of nematode eggs in the faeces of infected ostriches. Infected birds showed significantly higher DTD activity when compared to non-infected birds (Student’s t test, p < 0.05) whilst the activities of SDH and GPX were statistically not altered (Student’s t test p > 0.05). MDA levels were significantly elevated in infected birds compared to controls (Student’s t test, p < 0.001). These results suggest that infected birds are under oxidative stress due to the parasitic infection . Key words: Cestodes, nematodes, glutathione peroxidase, DT-diaphorase, Succinate dehydrogenase, malodialdehyde
Antibiotic Resistance Patterns and Virulence Factors of Coagulase Negative Staphylococcus Associated with Urinary Tract Infections in Bulawayo Province, Zimbabwe
(SCIENCEDOMAIN international, 2016) Mbanga, Joshua; Masuku, Sithabile; Luphahla, Silence
Aims: To determine the antibiotic resistance patterns and virulence factors of coagulase negative Staphylococcus (CoNS) associated with urinary tract infections (UTIs). The virulence factors assayed for were the atl E and ica AB genes. The prevalence of the antibiotic resistance gene, mec A, was also determined. Place and Duration of Study: Southern Pathology Clinical Laboratories and the National University of Science and Technology microbiology department, between December 2012 and March 2015. Methods: A total of 754 urine samples were analyzed for bacteria by standard procedures. Fromthese, 126 isolates were positively identified as CoNS. Antimicrobial susceptibility testing of the isolated CoNS was done using the disc diffusion method.The polymerase chain reaction (PCR) was also carried out to detect the presence of the mec A, ica AB and atl E genes. Results: Antibiogram profiles showed that CoNS had high prevalences of resistance to nalidixic acid (88.1%), cotrimoxazole (72.2%) and oxacillin (69.8%).There were however high prevalences of sensitivity to nitrofurantoin (79.4%) and gentamycin (68.3%). A total of 106 (84%) isolates were resistant to three or more antibiotics and 12 multi-drug resistance patterns were observed. The most common pattern (resistance to nalidixic acid, ampicillin, oxacillin, tetracycline and cotrimoxazole) was exhibited by 33 isolates. A total of 40 CoNS isolates were then used to determine the prevalence of the mec A, ica AB and atl E genes. PCR results showed that most isolates 25/40 (62.5%) were positive for the mec A gene. The ica AB and atl E were detected in 32.5% and 25% of the isolates respectively. All isolates which were positive for both the mec A and ica AB genes showed resistance to multiple antibiotics. Conclusion: There is emerging antibiotic resistance in CoNS that cause UTI’s. The occurrence of both the mec A and ica AB genes in CoNS isolates may lead to an increase in antibiotic resistance
Antimicrobial resistance of Escherichia coli isolated from chickens with Colibacillosis in and around Harare, Zimbabwe.
(American Association of Avian Pathologists, 2012-11-14) Saidi, Bamusi; Mafirakureva, Prettimore; Mbanga, Joshua
Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC),can lead to great economic losses in the poultry industry. The aim of this study was to determine the prevalance of antibiotic resistance and antibiotic resistance and antibiotic resistance patterns in APEC in Zimbabwe. From 503 chickens diagnosed with Colibacillosis, 103 E. coli isolates were obtained. Isolation and identification of E. coli were carried out using microscopy and boichemical tests. The disc diffusion method was used to determine antibiotic susceptibility of the isolates to 8 commercial antibiotics. Many isolates exhibited resistance to more than one antibiotic. Antibiogram profiles indicated maximum resistance to tetracycline (100%), bacitracin(100%), and cloxacillin (100%) and a high prevalence of resistance to ampicillin(94.1%0. However; there were high prevalences of sensitivity to ciprofloxacin (100%) and gentamycin (97.1%). The isolates showed moderate rates of sensitivity to chloramphenicol and neomycin.All isolatesin this study showed multidrug resistance because they were all resistant to 3 or more antibiotics. Seven multidrug resistance patterns were observed. The most common pattern (resistance to ampicillin, bacitracin,cloxacillin and tetracycline) was exhibited by 30 isolates.Our findings show that there is emerging drug resistance in APEC associated with colibacillosis in Zimbabwe. The observed high level of multidrug resistance could hamper the treatment of colibacillosis in Zimbabwe.
An Assessment of the Extent of Bovine Milk Pollution by DDT used in Public Health in Zimbabwe
(Scientia Research Library, 2016) Basopo, N.; Brock, Gerome; Mnkandla, Sanele
Indoor residual spraying of dichlorodiphenyltrichloroethane (DDT) has been widely used in the control of malaria, and has been appreciated for its low cost and high effectiveness. Prolonged use, however, has adverse effects as DDT and its metabolites persist for long in the environment, resulting in human and animal contamination. Contamination in animals such as cattle may result from consuming contaminated water, feed and fodder. The aim of the study was to evaluate the extent of contamination of DDT and its metabolites in cow’s milk from five towns in Zimbabwe. Samples were collected from farms around Bulawayo, Chiredzi, Esigodini, Harare and Mutare with a total of n=24 samples. The pesticide residues were extracted using the quick, easy, cheap, rugged and safe (Quechers®) method and solid phase extraction and analysed using gas chromatography with electron capture detector. Total DDT was detected in all samples at levels higher than the maximum allowable residue limit. Harare and Mutare samples had the highest DDT levels of 0.38 μg/ml and 0.26 μg/ml respectively, as compared with samples from other regions (0.08-0.13 μg/ml). The DDT metabolite residues,1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD) and 1,1-dichloro- 2,2-bis(p-dichlorodiphenyl)ethylene (DDE), were also detected at varying levels in the samples. The results show the presence of DDT and its metabolite contaminants in bovine milk, posing a serious health risk to consumers. Alternatives to DDT may therefore need to be employed in the control of the malaria vector.
Biological and physical features of sisal (Agave sp.) varieties growing in Matebeleland region
(Academy Journals, 2010-10-26) Dube, S.; Chiyaka, Christinah
Five varieties of sisal growing around Matebeleland were studied to determine their biological properties. Morphometric data for Agave deserti are mean of full grown leaf dimensions were, length 64cm, width 9cm, thickness 4mm and fiber yield of 0.0359%. The average fiber length was 50cm and the breaking tensile strain of single ultimate fiber 161.84MPa. For Agave sisalana mean of full grown leaf dimensions were, length 170cm, width 14cm, thickness 5mm and fiber yield of 0.0303%. Average fiber length was 150cm. The breaking tensile strain of single ultimate fiber 88.42MPa. For Agave Americana(variety C) mean of full grown leaf dimensions were, length 215cm, width 22cm, thickness 10cm and fiber yield of 0.0030%. Average fiber length was 200cm. Breaking tensile strain of single ultimate fiber 26.98MPa. For Agave americana (variety D) mean full grown leaf dimensions were, length 200cm, width 22cm, thickness 9mm and fiber yield of 0.0037%. The breaking tensile strain of single ultimate fiber was 54.59MPa. For variety E mean full grown leaf dimensions, length 212cm, width 22cm, thickness 8mm and fiber yield of 0.026%. The terminal spine was absent. The breaking tensile strain of single ultimate fiber 171.16MPa. All the varieties attain full maturity in 5-20 years. Propagation is by bulbils and offsets. Cross sections of the fibres are horse shoe shaped for A, B and E and are lunar shaped for C and D.
Biological oxidants and antioxidants
(2013) Naik, Yogeshkumar S.
The generation of reactive oxygen species, such as the supcroxideanionradical and hydroxyl radical, is known to lead to a variety of pathological conditions. Antioxidants such as vitamins A, C, Eand antioxidant enzymes are known to prevent the deleterious elfects of these toxic radicals. THe role of free radicals in disease may be most familiar to readers of the literature on postischacmic organ reperfusion injury. However, recent studies have shown that these radicals may also play a role in the ageing process, artherosclerosis, carcinogenesisa and even Diabetes mellitus
Carbaryl and Dimethoate Induced Alterations of the Antioxidant Defense System in Two Freshwater Pulmonate Snails Helisoma Duryi and Lymnaea Natalensis
(Scholars Research Library, 2016) Basopo, N.; Naik, Yogeshkumar S.
Organophosphates and carbamates are extensively used to increase the quality and quantity of field crops. These pesticides may indirectly enter water bodies where they affect aquatic organisms. Once absorbed by aquatic organisms the pesticides are metabolised and normal metabolic processes may produce reactive oxygen species that have adverse effects on the aquatic organisms. The effects of exposure to carbaryl and dimethoate pesticides on antioxidant enzymes of two freshwater snail species Helisoma duryi and Lymanea natalensis were evaluated. Groups of snails were exposed to 25 ppb of carbaryl and/or dimethoate for 72 hours. After the exposure duration they were then analysed for their effects on the oxidative defense systems of the snails. Increased thiobarbituric acid reactive substances levels and activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione S-transferase in both snail species were observed, probably as a means of combating oxidative stress due to pesticide poisoning. Increased lipid peroxidation, coupled with altered levels of oxygen free radical scavenging enzymes in snail homogenates are discussed in relation to oxidative stress.
Ceylonocotyle, Bothriophoron, and Calicophoron species Parasitic in some Nigerian Cattle
(Society of Education, 2013-06) Dube, S.; Onyedineke, N.E.; Aisien, M.S.O.
The following genera Ceylonocotyle, Bothriophoron and Calicophoron were recovered from the inner walls of stomachs of cattle slaughtered in abattoirs in the North and South of Nigeria. Some parasites were flattened and diagnostic features taken while some were sectioned in the median saggital plane from where the histology and morphology of the pharynx, genital atrium, acetabulum and testis were analysed for identification. Ceylonocotyle dicranocoelium. Bothriophoron bothriophoron, Calicophoron calicophorum, and Calicophoron microbothrioides were identified. Photomicrographs of the features used in identifications were made and are here presented. Damage to host tissues of the reticulum and rumen was in the majority of cases severe when Ceylonocotyle dicranocoelium was present but the other species did less damage to rumens and reticulum. Parasite loads ranged between 20 and 200 parasites in the infected animals and frequencies of occurrence in cattle were 10% for Ceylonocotyle dicranocoelium, 2 % for B. bothriophoron, 15% for C. calicophorum, and 5 % for C. microbothrides. All the described parasites are being reported in Nigeria for the first time.
Characterization of Fasciola gigantica isolates from cattle from South-western Zimbabwe using RAPD-PCR
(International Organization Of Scientific Research (IOSR)., 2014) Chauke, E.; Dhlamini, Zephaniah; Mbanga, Joshua; Dube, S.
The study sought to characterize Fasciola gigantica isolates from cattle in different localities using RAPD-PCR. Adult flukes morphologically identified as F. gigantica were collected from slaughtered infected animals during meat hygiene inspections. DNA was extracted from single flukes and subjected to RAPD-PCR analysis. In the RAPD-PCR analysis, genomic DNA isolated from the conical anterior end of the worms was amplified by the polymerase chain reaction using 10 random oligonucleotide primers. Depending upon the Fasciola gigantica isolate-primer combination, 1-13 DNA fragments in the range of 75-2000bp were amplified. It was observed that all the 10 primers directing amplification of DNA were of potential interest in the generation of polymorphic DNA. The percentage polymorphic loci ranged from 33.33-100%. Polymorphic bands were scored and used to calculate Nei’s 1978 genetic distance. The genetic distance values ranged between 0.0690 (isolate 5 and 6 from Gwanda and 0.6109 (isolate 6 from Gwanda and isolate 14 from Matopo). The mean Nei’s gene diversity was 0.2839. The study showed the variability of Fasciola gigantica isolates from the same host, using RAPD markers could be applied as a low cost way of identification
Chemical composition and physical characteristics of cowpea haulms as forage for ruminants
(South African Society of Animal Science, 2000) Mokoboki, H.K.; Ayisi, K.K.; Ndlovu, Lindela R
Cowpea ( Vigna unguiculata) is a major grain legume grown by small- scale farmers in the Northern Province of South Africa. The crop is indigenous to Africa and is used extensively in many cropping systems throughout Africa (Eaglesham et al., 1981). Cowpea straws are potential supplementary feed for ruminants in the dry season. Cowpea straws are likely to have higher crude protein than cereal straws and may thus improve digestibility of cereal straws if used together. However, cowpea straws may contain anti-nutritional factors such as tannins and total phenols which affect animal performance. The protein and tannin content of cowpea straws is likely to be affected by variety and growth environment. Straws of varieties adapted to Northern Province have not been evaluated for their content of these constituents. Whilst animal intake and utilisation are the ultimate test of forage suitability, the procedures are unsuitable when large number of forage germ-plasm are to be screened. Chemical and physical characteristics that are known to affect intake and utilisation are often used in such circumstances. The main aim of this research was to determine the effect of variety on physical and chemical characteristics of straws of long season cowpeas and also to determine if haulms of varieties that retain greenness longer will have a better nutritional value than those that dry early.
Combined use of phenyl-bonded phase clean-up and HPLC for the determination of aflatoxins
(Tropical Science, 1996) Siwela, Andrew H.
Phenyl·bonded phase clean-up and HPLC were used to measure aflatoxins in groundnuts, peanut butter, beans, cowpeas and maize meant for human consumption. Of 277 samples, 84% were al or bleow the 20 pp.b. limil. Of 100 animal feed samples, 28% were at or below 5 p.p.b., the proposed limit infeedfor milk-producing animals.
A comparison of antibiotic resistance in microorganisms isolated from chicken and ostrich faeces in Bulawayo, Zimbabwe
(International Formulae Group., 2007) Siwela, Andrew H.; Matsaure, Fradereck; Ncube, T.; Olonitola, Olayeni S.; Best, Geoffrey R.
Samples of fresh faeces were obtained from a free-range chicken source, three commercial chicken farms and a commercial ostrich farm, all located around Bulawayo City, Zimbabwe, in order to determine the antibiotic resistance profile of selected bacterial isolates of interest in food-related human infections. Samples were prepared at various dilutions and plated on selective media for Coryneforms, Escherichia coli, Enterococcus faecalis and Pseudomonas. The targeted bacteria were isolated as pure cultures and tested for antibiotic resistance to ampicillin, chloramphenicol, oxytetracycline, sulphonamide, streptomycin and tetracycline. Isolates from the faeces of chickens and ostriches in the commercial farms were found to be generally more resistant to streptomycin, tetracycline and oxytetracycline as compared to those from the free- range chickens. This study emphasizes the need to monitor antibiotic resistance genes in the environment and to curb/curtail antibiotic use for growth promotion in farm animals, particularly in developing countries, as continued use will only add to the growing problem of microbial antibiotic resistance.
A comparison of metal levels and antioxidant enzymes in freshwater snails, Lymnaea natalensis, exposed to sediment and water collected from Wright Dam and Lower Mguza Dam, Bulawayo, Zimbabwe
(Elsevier Inc., 2010-08) Siwela, Andrew H.; Nyathi, C.B.; Naik, Yogeshkumar S.
We compared the bioaccumulation of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), nickel (Ni) and iron (Fe) with antioxidant enzyme activity in tissues of the snails, Lymnaea natalensis, exposed to elements of two differently polluted dams. 45 snails were exposed to sediment and water collected from Wight Dam (reference) whilst another 45 snails were also exposed to sediment and water collected from Lower Mguza Dam (polluted dam). Except for Fe in sediment and Pb in water, metal concentrations were statistically higher in sediment and water collected from Lower Mguza Dam. Lead, Cd and Zn were two times higher in tissues of snails exposed to Lower Mguza Dam elements. On one hand, superoxide dismutase (SOD), diphosphotriphosphodiaphorase (DTD) and catalase (CAT) activities were significantly lower whilst malondialdehyde (MDA) levels were significantly higher in tissues of snails exposed to Lower Mguza Dam sediment and water. On the other hand, selenium-dependent glutathione peroxidase (Se-GPX) activity was significantly elevated in tissues of snails exposed to Lower Mguza Dam sediment and water. Snails exposed to Lower Mguza Dam elements seem to have responded to pollution by increasing CAT and Se-GPX specific activity in an effort to detoxify peroxides produced as a result of metal induced oxidative stress.
A comparison of metal levels and antioxidant enzymes in freshwater snails,Lymnaea natalensis, exposed to sediment and water collected from Wright Dam and Lower Mguza Dam, Bulawayo, Zimbabwe.
(Elsevier Inc., 2010-08-02) Siwela, Andrew H.; Nyathi, C.B.; Naik, Yogeshkumar S.
We compared the bioaccuniulation of lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), nickel (Ni) and iron (Fe) with antioxidant enzyme activity in tissues of the snails, Lymnaea natalensis, exposed to elements of two differently polluted dams. 45 snails were exposed to sediment and water collected from Wight Dam (reference) whilst another 45 snails were also exposed to sediment and water collected from Lower Mguza Dam (polluted dam). Except for Fe in sediment and Pb in water, metal concentrations were statistically higher in sediment and water collected from Lower Mguza Dam. Lead. Cd and Zn were two times higher in tissues of snails exposed to Lower Mguza Dam elements. On one hand, superoxide dismutase (SOD), diphosphotriphosphodiaphorase (DTD) and catalase (CAT) activities were significantly lower whilst malondialdehyde (MDA) levels were significantly higher in tissues of snails exposed to Lower Mguza Dam sediment and water. On the other hand, selenium-dependent glutathione peroxidase (Se-GPX) activity was significantly elevated in tissues of snails exposed to Lower Mguza Dam sediment and water. Snails exposed to Lower Mguza Dam elements seem to have responded to pollution by increasing CAT and Se-GPX specific activity in an effort to detoxify peroxides produced as a result of metal induced oxidative stress.
A Comparison Of Organochlorine Pesticide Residues In Upper Ncema And Lower Umguza Dams, Zimbabwe.
(Journal of Applied Science in Southern Africa, 1996) Siwela, Andrew H.; Marufu, G.; Mhlanga, A.T.
This study examined the levels of chlorinated hydrocarbons (organochloride pesticides) in the ecosystem of Ncema and Umguza dams. Samples of water, water weeds, mud and fish were collected from each dam. The fish species collected from the two dams were river sardine (Mesobo/a brevianus), branded bream (Tilapia sparmanii), African catfish (e/arias gariepinus) and red-breasted bream (Tilapia rendelli). The samples were analysed for hexachlorocyclohexane, DDT, and its metabolites, DOE and DOD, aldrin and dieldrin. DDT was detected in all the samples, its concentration ranging from 1,12 J.l9 per kg in water weeds to 265 J.l9 per kg in mud from Upper Ncema dam. Aldrin was also detected in all the samples (except for branded bream from Upper Ncema dam), the highest level __being 223 ~g per kg in_ ~atdln~$'-rom Lower Umguza dam. Traces.of hexachlorocyclohexane were detected in some of the samples, the highest level of 20,1 ~g per kg in African catfish from Upper Ncema dam. Dieldrin was detected only in mud samples from Lower Umguza dam at a concentration of 80,5 ~g per kg. Overall, this study indicates that Upper Ncema dam has a higher pesticide load compared to Lower Umguza dam.
Consumer's views and use of labels on food items sold in Bulawayo urban province, Zimbabwe
(African scholarly science communication trust., 2017-11) Ncube, T.; Makurunje, S; Dube, S.
Food labels are a medium by which consumers acquire knowledge about packaged foods they are considering to purchase. The label makes the first impression about a product and has a great effect on the purchasing decision for consumers. In recent years, literate consumers have become interested in nutritional issues. Lifestyle, age, dietary and safety concerns have been the contributing factors to nutritional awareness by consumers. Nutritional labels can generally have a positive impact on food consumption and may save health-care costs for those consumers with health concerns. On the other hand, for those consumers who are illiterate, price may be more important in making purchase decisions. This study intended to investigate how consumers in Bulawayo Urban Province (Zimbabwe) view and use labels on packaged food items. Seventy-five randomly selected consumers were questioned about their perceptions, attitudes and use of label information using open ended structured questionnaires. The consumers were selected on the basis of being present at the supermarkets at the time of sampling. The respondents were interviewed at different times of the day to cater for employed and unemployed people. The results obtained indicate that the extent to which food labels are used depends on factors such as price of food products, individual health needs and gender. For consumers who use food labels to make their purchase decisions, not all the information on the label is considered. Items on the labels to which the consumers responded were brand, nutritional profile and mass of product in relation to the price. The label elements which were extensively used by consumers in this study are date mark (81.3%), weight of food (89.3%) and price (77.3%). The least used element is the nutritional panel (50.7%). About 44% of the consumers were not sure about the trustworthiness of the information given on food labels. Food labels are important to a greater extent for people with special dietary requirements, while the remainder of the studied population are influenced by price in their purchase decisions. Consumers seem not to understand some of the information on the food labels because of the difficulties in interpreting what is written.
Current Status of Mycotoxin Contamination of Food Commodities in Zimbabwe
(MDPI, 2018-05-03) Nleya, N.; Adetunji, Modupeade.C; Mwanza, M.
Agricultural products, especially cereal grains, serve as staple foods in sub-Saharan Africa. However, climatic conditions in this region can lead to contamination of these commodities by moulds, with subsequent production of mycotoxins posing health risks to both humans and animals. There is limited documentation on the occurrence of mycotoxins in sub-Saharan African countries, leading to the exposure of their populations to a wide variety of mycotoxins through consumption of contaminated foods. This review aims at highlighting the current status of mycotoxin contamination of food products in Zimbabwe and recommended strategies of reducing this problem. Zimbabwe is one of the African countries with very little information with regards to mycotoxin contamination of its food commodities, both on the market and at household levels. Even though evidence of multitoxin occurrence in some food commodities such as maize and other staple foods exist, available published research focuses only on Aspergillus and Fusarium mycotoxins, namely aflatoxins, deoxynivalenol (DON), trichothecenes, fumonisins, and zearalenone (ZEA). Occurrence of mycotoxins in the food chain has been mainly associated with poor agricultural practices. Analysis of mycotoxins has been done mainly using chromatographic and immunological methods. Zimbabwe has adopted European standards, but the legislation is quite flexible, with testing for mycotoxin contamination in food commodities being done voluntarily or upon request. Therefore, the country needs to tighten its legislation as well as adopt stricter standards that will improve the food safety and security of the masses.
Cytosolic glutathione s-transferases of ostrich liver.
(2015-04-09) Naik, Yogeshkumar S.; Kanyepi, R.; Ndiweni, N.; Hasler, Julia A.; Nyathi, C.B.
Chemicals consummumed by the ostrich are likely to be metabolised by liver detoxifying enzymes such as the cytosolic glutathione Stransferases (GST). We have studied the affinity purified GST from male and female ostrich livers. 1-chloro-2, 4-dinitrobenzene (CDNB) proved to be the best of several substrates tested to measme activity. Activity with this substrate was inhibited by sulphobromoptgnalein and cibamon blue which are well established inhibitors for the m ammalian enzyme. A number of pesticides and environmentai pollutants were also found to be strong inhibitors of the enzymes. Our data indicates that ostrich liver enzymes behave similarly to the mammalian liver enzyme in terms of substrate requirements and inhibition characteristics.

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