烟台市售食品黄曲霉毒素污染状况及膳食暴露评估

目的 了解烟台市售食品黄曲霉毒素污染状况及居民膳食来源暴露风险水平。方法 免疫亲和层析高效液相色谱法测定样品中黄曲霉毒素,点评估方法估算人群黄曲霉毒素暴露量。结果 检测的市售食品中AFB1检出率为4.19%（19/453）,超标率为0.22%（1/453）,均值为0.86 μg/kg。AFB2、AFG1、AFG2和AFM1检出率分别为2.13%（9/423）、1.65%（7/423）、0.95%（4/423）和41.90%（44/105）,均值分别为0.29、0.64、0.33和 0.03 μg/kg。食品中存在AFB1、AFB2、AFG1和AFG2多重污染情况。AFB1的检出均值占到黄曲霉毒素(AFB1、AFB2、AFG1和AFG2)均值总和的47.18%。AFB1、AFB2、AFG1、AFG2和AFM1的日膳食暴露量分别为4.326、1.733、3.143、2.423和0.168 ng/（kg·bw·d）。AFB1、AFB2、AFG1、AFG2和AFM1的膳食暴露贡献率分别占到总体的36.69%、14.70%、26.65%、20.55%和1.42%。谷类及其制品的膳食暴露贡献最大,食用植物油的贡献次之。结论 AFB1总体检出率和均值均高于AFB2、AFG1和AFG2,是主要的污染品种。谷类及其制品和食用植物油是主要的AFB1、AFB2、AFG1和AFG2膳食暴露来源。乳制品是主要的AFM1的膳食暴露来源。烟台市居民AFB1和AFM1膳食暴露导致肝癌发病率为0.101/10万人和0.004/10万人。     

玉米中四种黄曲霉毒素的关系

目的了解我国玉米中黄曲霉毒素B1（AFB1）、黄曲霉毒素B2（AFB2）、黄曲霉毒素G1（AFG1）和黄曲霉毒素G1（AFG1）污染的关系。方法用统计方法分析玉米中任意两种毒素污染率、污染浓度的相关性;计算AFB1与总黄曲霉毒素（AFs）的数量关系,分析AFB1在AFs中的构成1结果AFB1检出率最高,AFB1没有单独污染,均伴随AFB1。任两种毒素浓度呈正相关（P=0．000）,AFB1、AFB1、AFG1与AFG1的相关系数均大于0．951任两种毒素检出率有相关性（P=0．000）,AFB1和AFBz相关性最强1随AFB1浓度区间增高,AFB1检出率增高,AFG1和AFG1检出率先升高后降低;AFB1与AFs浓度比升高,AFs高于4μg／kg时,浓度比超过0．51结论AFB1和AFBz污染密切相关,AFBz伴随AFB1,二者污染率和浓度呈正向变化。当AFB1浓度较高时,对AFG1和AFG1呈现抑制作用1按照AFs限量是AFB1的两倍,当玉米中AFs限量在4μg／kg以上时,同时制定AFB1和AFs限量,与仅制定AFB1限量相比,不增加管理效力。     

Inhibition of aflatoxin production and growth of Aspergillus parasiticus by Cuminum cyminum, Ziziphora clinopodioides, and Nigella sativa essential oils

Aflatoxins are highly toxic and carcinogenic metabolites produced by Aspergillus parasiticus on food and agricultural commodities. Natural products may control the production of aflatoxins. The aims of this study were to evaluate the effects of the essential oils (EOs) of Cuminum cyminum, Ziziphora clinopodioides, and Nigella sativa on growth and aflatoxins production by A. parasiticus. Minimal inhibitory concentrations (MICs) and minimal fungicidal concentrations (MFCs) of the EOs were determined and compared with each other. Determination of aflatoxins (AFB(1), AFB(2), AFG(1), and AFG(2)) was performed by immunoaffinity column extraction using reverse phase-high performance liquid chromatography. The major oil components were α-pinene (30%) in C. cyminum, pulegone (37%) in Z. clinopodioides, and trans-anthol (38.9%) in N. sativa oils. In broth microdilution method, C. cyminum oil exhibited the strongest activity (MIC(90): 1.6; MFC: 3.5?mg/mL), followed by Z. clinopodioides (MIC(90): 2.1; MFC: 5.5?mg/mL) and N. sativa (MIC(90): 2.75; MFC: 6.25?mg/mL) oils against A. parasiticus (p<0.05). Aflatoxin production was inhibited at 0.25?mg/mL of C. cyminum and Z. clinopodioides oils, of which that of C. cyminum was a stronger inhibitor. C. cyminum EO caused significant reductions in values of 94.2% for AFB(1), 100% for AFB(2), 98.9% for AFG(1), 100% for AFG(2), and 97.5% for total aflatoxin. It is concluded that the EOs of C. cyminum, Z. clinopodioides, and N. sativa could be used as natural inhibitors in foods at low concentrations to protect from fungal and toxin contaminations by A. parasiticus.     

Aflatoxins and ochratoxin A in food and risks to human health

OBJECTIVES: The presence of mycotoxins in food has been associated with several human diseases, and health authorities have taken actions to decrease the ingestion of these compounds in the diet. A study was carried out to assess aflatoxins and ochratoxin A concentrations found in food, and to evaluate the potential risk to human health resulting from mycotoxin exposure. METHODS: Between July 1998 to December 2001, 366 food samples were analyzed, including peanuts and its products, nuts, maize, oat and/or wheat products, rice and beans. Samples were processed and the extracted mycotoxins were detected and separated using thin layer chromatography, and then quantified with fluorescence. RESULTS: Aflatoxins were detected in 19.6% of the samples: raw peanuts and its products, pop corn, maize and Brazilian nuts (>2mg/kg). Peanuts and its products showed the highest levels of aflatoxin contamination (34.7%) with up to 1280 mg/kg of AFB1+AFG1 and 1706 mg/kg of total aflatoxins. Of the positive samples, AFB1 was detected in 98.5%, AFB2 in 93%, AFG1 in 66.7%, and AFG2 in 65.4%. Ochratoxin A was not detected (<25 mg/kg) in any sample analyzed. CONCLUSION: It was found that contamination levels mainly seen in peanuts and its products exceed Brazilian regulated standards, and they can be a potential risk to regular consumers of these products. Food producers' awareness allied to monitoring programs is essential to reduce human exposure to these compounds and prevent ensuing chronic diseases.     

Bacteriological quality of weaning food and drinking water given to children of market women in Nigeria: implications for control of diarrhoea

Bacteriological quality of weaning food and drinking water given to 2 groups of children aged < or = years was evaluated by estimating bacterial cell count. One group consisted of those taken to market and the other of those left at home in the care of older siblings or house-helps. Bacterial counts (geometric mean) ranged from 5.02 +/- 1.82 to 8.70 +/- 1.0 log10 cfu per g or mL of food, and from 1.15 +/- 1.67 to 6.53 +/- 0.81 log10 cfu per g or 100 mL of water. Analysis of variance showed no significant difference in counts between types of food and between meals (breakfast and lunch). Bacterial contamination increased significantly with storage time, and was, in all circumstances except the water samples, significantly higher in foods given to children left at home. Reheated leftover foods also had significantly higher bacterial load than the freshly-cooked food. Coliform count varied significantly with source of drinking water. Poor hygiene standard (inferred from bacterial contamination) was generally observed among mothers weaning < or = 2-year-old children, while they were engaged in trading activities in the market, thus exposing their children to high risk of diarrhoea. Hygiene was significantly poorer in weaning of children left at home in the care of older siblings or house-helps. This implies that, in spite of their trading activities in the market, mothers still take better care of their babies than the older siblings or house-helps who may be inexperienced. These mothers may need education on childcare and food hygiene to suit to their trading activities, for example, during their monthly meetings. There is also a need to establish ORT (oral rehydration therapy) corners in the markets as part of the municipal services. This can be used not only for efficient and quick management of diarrhoea in the market but also for reinforcing hygiene education.     

抗黄曲霉毒素B_1蛋黄抗体的制备及其性质的研究

将黄曲霉毒Ｂ１－牛血清白蛋白（ＡＦＢ１Ｏ—ＢＳＡ）连接物免疫注射４只（Ａ、Ｂ、Ｃ、Ｄ）产蛋鸡。研究了抗ＡＦＢ１蛋黄抗体的产生进程,除鸡Ｂ外,其它３只鸡从第一次注射抗原后的第９０天开始有较明显的抗体产生,第１３５天达到高峰,从第１６５天开始下降。在抗体产生高峰期,蛋黄抗体Ａ、Ｃ、Ｄ的间接ＥＬＩＳＡ效价分别为１∶８０００、１∶６０００、１∶６０００。以蛋黄抗体Ａ为材料,研究了抗体的特异性,结果表明：该抗体有较好的特异性。但是抗体与ＡＦＢ１的结构类似物（ＡＦＢ２、ＡＦＧ２、ＡＦＧ１、ＡＦＭ１）除ＡＦＭ１外都有不同程度的交叉反应,达到５０％的竞争抑制率时,ＡＦＢ１、ＡＦＢ２、ＡＦＧ１、ＡＦＧ２的灵敏度分别为６、２５、１２５和２４９５ｎｇ／ｍｌ。     

中国部分地区玉米中4种黄曲霉毒素污染调查

目的了解中国玉米中黄曲霉毒素B1(AFB1)、黄曲霉毒素B2(AFB2)、黄曲霉毒素G1(AFG1)和黄曲霉毒素G2(AFG2)的污染状况。方法从吉林、河南、湖北、四川、广东、广西采集玉米样品,用HPLC测定黄曲霉毒素含量。结果共测定279份玉米,黄曲霉毒素阳性率为75.63%,阳性样品平均浓度为44.04μg/kg,浓度范围0.20～888.30μg/kg。四川、湖北、广西、河南、广东和吉林样品的阳性率依次为90.48%、93.75%、87.50%、36.96%、91.84%和52.17%,平均浓度依次为107.93、70.98、39.65、8.06、3.70和1.15μg/kg。4种毒素中AFB1阳性率和平均浓度最高,分别为74.55%和39.64μg/kg;AFB2、AFG1和AFG2的阳性率和平均浓度依次降低,阳性率分别为58.42%、41.22%和19.71%,平均浓度分别为3.81、3.47和0.51μg/kg。结论玉米的黄曲霉毒素污染比较普遍;调查的各地样品均有不同程度污染,总体上南方地区高于北方;4种毒素中以AFB1污染为主。     

上海浦东新区谷物、豆类及其制品中黄曲霉毒素的污染调查

目的了解上海市浦东新区谷物、豆类及其制品中黄曲霉毒素(B_1、B_2、G_1、G_2)的污染现状,为相关食品中黄曲霉毒素污染监测提供基础数据。方法 2016年4~8月期间在浦东新区8家超市和5家菜市场进行随机抽样,采集市售谷物、豆类及其制品共计190件样品,样品经多功能净化柱净化提取后,使用超高液相色谱荧光法测定4种黄曲霉毒素含量,最终数据用SPSS 16.0进行统计分析。结果 190件样品中黄曲霉毒素检出率为22.63%,AFB_1超标率为1.05%;比较黄曲霉毒素检出率,豆类及其制品高于谷物及其制品,散装样品高于定型包装样品;4种黄曲霉毒素的检出率AFB_1AFB_2AFG_1AFG_2。结论上海市售谷物、豆类及其制品不同程度的受到黄曲霉毒素的污染,有必要对相关食品进行定期监测,特别是散装制品,尤其需要加强管理监督。建议有关部门制定食品中黄曲霉毒素总量限值,为食品安全监测和评估提供依据。     

The effect of bread making steps on the degradation of aflatoxins produced as a result of single inoculation with Aspergillus flavus and combined inoculation with Aspergillus flavus and Aspergillus ochraceus

This study aimed to determine the effect of bread making steps on the stability of aflatoxin. Sakha 8 wheat and Gemaiza 5 wheat cultivars, were used in the present study. They were inoculated with a dense spore suspension of toxigenic fungal species of Aspergillus flavus and a non toxigenic species of Aspergillus ochraceus singly and combined. Aflatoxin concentration was determined in the whole wheat grain, after milling, after fermentation, and after bread-baking process. Results showed that the highest reduction percentage for the total aflatoxins (81, G1 and G2), was in Sakha 8 (32.96%) (single treatment), Gemaiza 5 (19.54%) (single treatment ), Gemaiza 5 (18.65%) (combined treatment), and finally in Sakha 8 (16.49%) (combined treatment). There was no significant difference (p < 0.05) in aflatoxins content between Sakha 8 and Gemaiza 5 treated singly and in a combined way before and after milling process. In the mean time, the percentage of AFB1, AFG1 and AFG2 were reduced by 31.98%, 44.53% and 35.35%, respectively, while the total aflatoxins concentration were reduced by 41.17% after baking. Results also showed the presence of a significant difference at p < 0.05 among the whole grain, after milling and after baking concerning AFG1, AFG2 and the total aflatoxins content. No significant difference was found in case of AFB1.     

Ionic liquid functionalized zinc oxide nanorods for solid-phase microextraction of aflatoxins in food products

Aflatoxins (AFs) in food and agricultural products pose serious health hazards to consumers. As a result, exports are restricted and farmers lose much needed income. One major challenge faced in controlling AFs in developing countries in particular is lack of simple and cost-effective methods of analysis. To address this problem, a solid-phase microextraction (SPME) technique was developed based on 1-hexyl-3-methylimidazolium hexafluorophosphate functionalized zinc oxide nanorods for the extraction of AFB1, AFB2, AFG1 and AFG2 in food products prior to HPLC analysis. The SPME was performed using 10 mg of the adsorbent at pH 7 and vortexing for 1 min at 500 rpm, and desorbed by sonication for 2 min in 1 mL acetonitrile. The technique showed excellent linearity (correlation coefficients, ≥0.997). LOD and LOQ were determined respectively to be 0.07 and 0.73 μg/kg for AFB1, 0.01 and 0.12 μg/kg for AFB2, 0.04 and 0.44 μg/kg for AFG1 and 0.02 and 0.18 μg/kg for AFG2. The intra- and inter-day relative standard deviations were in the ranges of 3.9–4.7% and 6.9–8.4%, respectively. The acquired recovery of blank samples of the pepper and groundnut samples spiked with mixed analytes at 5 and 10 μg/kg spiking levels were in the range of 88.6–99.8%. The SPME was employed for the analysis of the considered analytes from real chili pepper and processed groundnut samples. Overall, the technique is easy, fast, cost-effective and environmentally friendly and can be used for the analysis of AFs in various food and agricultural products.     

抗黄曲霉毒素B1蛋黄抗体的制备及其性质的研究

将黄曲霉素Ｂ１－牛血清白蛋白（ＡＦＢ１Ｏ－ＢＳＡ）妆物免疫注射４只（Ａ、Ｂ、Ｃ、Ｄ）产蛋鸡。研究了抗ＡＦＢ１蛋黄抗体的产生进程，除鸡Ｂ外，其它３只鸡从第一次注射搞后的第９０天开始有较明显的抗体产生，第１３５天达到高峰，从第１６５天开始下降。在抗体产生高峰期，蛋黄抗体Ａ、Ｃ、Ｄ的间接ＥＬＩＳＡ效价分别为１：８０００、１：６０００、１：６０００。以蛋黄抗体Ａ为材料，研究了抗体的特异性，结果表明，该抗体     

Bacterial contamination of blenderized whole food and commercial enteral tube feedings in the Philippines

Hospital-prepared tube feedings from four Philippine acute-care hospitals were analysed for microbial contamination. Two feedings were prepared on three separate days at each hospital. The tube feedings were either blended natural whole foods or a reconstituted commercial powdered nutritional product. Samples of each feeding were collected for coliform count and standard plate count at the time of preparation and at 1, 2 and 4 h after preparation after maintenance at room temperature (26-31 degrees C).At the time of preparation, mean coliform and standard plate counts for all samples were 10.3 most probable number per gram (MPN/g) and 7.4x10(4)colony-forming units per gram (cfu/g), respectively. Nine of 24 samples (38%) had coliform counts greater than 10 MPN/g, and 22/24 (92%) samples had standard plate counts greater than 10(3) cfu/g. There were significant increases in mean coliform and standard plate counts over 4 h (P=0.0005 and P=0.008, respectively). At 4 h after preparation, the mean coliform and standard plate counts were 18.2 MPN/g and 2.1x10(5) cfu/g, respectively. At this time, 18/24 (75%) samples had coliform counts greater than 10 MPN/g and 20/24 (83%) samples had standard plate counts greater than 10(5) cfu/g. The results of this study show that the microbial quality of the majority of the hospital-prepared enteral tube feedings analysed were not within published guidelines for safety.     

Assessment of safety of frozen foods

This study aimed to assess the microbiological quality of 90 frozen food samples (50 samples of raw frozen vegetables including molokeya, okra, green peas, peas + carrot, and artichoke, 20 of frozen poultry products and 20 of frozen meat products), and to assess the level of women practice during handling. A cross-sectional study was conducted. Results showed that the mean aerobic mesophilic plate count of frozen vegetables was 3.4 x 10(5) +/- 7.3 x 10(5) cfu/g. The mean mold and yeast count was 3.9 x 10(3) +/- 1.1 x 10(4) cfu/g. The mean coliform count was 3.9 x 10 +/- 6.6 x 10 m.o./g. In case of meat product, the mean aerobic count was 2.3 x 10(5) +/- 3.2 x 10(5), that of mold and yeast was 2.5 x 10(5) +/- 8.8 x 10(5) cfu/g and that of coliform was 3.2 x 10(2) +/- 3.8 x 10(2) m.o./g. Poultry products on the other hand had a mean aerobic count of 6.8 x 10(5) +/- 1.6 x 10(6), a mean mold and yeast count of 3.5 x 10(5) +/- 7.4 x 10(5) cfu/g and a mean coliform count of 6.4 x 10(2) +/- 5.2 x 10(2) m.o./g. Fecal coliforms were detected only in 60.0% of meat product samples and in 45.0% of poultry product samples. On the other hand Staph aureus was detected only in 10.0% of poultry product samples. Difference between the 5 types of vegetables was statistically significant (P = 0.00, and 0.02, respectively) for total plate and mold and yeasts counts. Among the 113 interviewed women, 80 used frozen food products. Twenty six of them (32.5%) had scores < 50%, those were classified as being bad as they were handling frozen food improperly which would contribute to outbreaks of food borne diseases. Less than 4% of the users used satisfactory practice during handling frozen foods. Illiteracy affected significantly the level of practice.     

Aflatoxins and kwashiorkor: clinical studies in Sudanese children

Aflatoxin analysis of blood and urine by high performance liquid chromatography in 584 Sudanese children is reported. The results in 404 malnourished children comprising 141 kwashiorkor, 111 marasmic kwashiorkor and 152 with marasmus are compared with 180 age-matched controls and correlated with clinical findings. The aflatoxin detection rate and mean concentration were higher in serum of children with kwashiorkor than the other groups. The difference between the detection rate in kwashiorkor and controls was significant (p less than 0.05). The aflatoxin detection rate in urine was highest in the marasmic kwashiorkor group and the mean concentration was higher in the marasmic kwashiorkor and marasmic groups than in the kwashiorkor and control groups. There were important differences in the detection of certain aflatoxins between the groups. Aflatoxicol was detected in the sera of 16 (11.6%) kwashiorkor, in six (6.1%) marasmic kwashiorkor, but in none of the controls and only once in marasmus. These differences are highly significant (p less than 0.0001). The ratio of AFB1 to AFM1 was higher in the sera and urines of kwashiorkors than in controls, suggesting that the normal transformation of AFB1 to AFM1 may be impaired in kwashiorkor with consequent increase in transformation of AFB1 to aflatoxicol. The study therefore provides evidence of differences in the metabolism of aflatoxins in children with kwashiorkor compared with children with other forms of malnutrition and normally nourished children and confirms the association between aflatoxins and kwashiorkor contained in a preliminary report on this work.     

The microbiological quality of ready-to-eat foods with added spices

A microbiological study of ready-to-eat foods with added spices or spice ingredients was undertaken to identify any risk factors in the production, storage and display of this product and to establish their effect on microbiological quality. Examination of 1946 ready-to-eat foods from sandwich bars, cafés, public houses, restaurants, specialist sandwich producers, bakers, delicatessens, market stalls and mobile vendors found that 1291 (66%) were of satisfactory/acceptable microbiological quality, 609 (32%) were of unsatisfactory quality, and 46 (2%) were of unacceptable quality. Unacceptable results were due to high levels of B. cereus and/or other Bacillus spp. (>/=10(5) cfu g(-1)). Unsatisfactory results were mostly due to high Aerobic Colony Counts (up to >/=10(7) cfu g(-1)), Enterobacteriaceae (>/=10(4) cfu g(-1)), Escherichia coli (>/=10(2) cfu g(-1)), and Bacillus spp (>/=10(4) cfu g(-1)). Examination of 750 spices and spice ingredients revealed that B. cereus were present in 142 (19%) samples, other Bacillus spp. in 399 (53%) samples, and Salmonella spp. (S. enteritidis PT 11) in one (<1%) sample. Approximately a third (222) of spice and spice ingredients examined contained high counts (>/=10(4) cfu g(-1)) of B. cereus and/or other Bacillus spp., and appeared to be associated with the corresponding ready-to-eat foods containing similar high counts of these organisms (P<0.0001). Acceptable microbiological quality of ready-to-eat foods to which spices or spice ingredients have been added was associated with premises that had management food hygiene training and hazard analysis in place. Poor microbiological quality was associated with preparation on the premises, premises type, little or no confidence in the food business management of food hygiene, and small premises as indicated by local authority inspectors' confidence in management and consumer at risk scores.     

Occurrence of Listeria species in prepacked retail sandwiches.

A survey of 725 prepacked sandwiches was conducted examining for the presence on enrichment, and by plate count, of Listeria species. Sandwiches were found to contain Listeria sp. more frequently than their component foods. Chicken, beef and bacon fillings were associated with more frequent isolation. Salad also was associated with more frequent isolation, but the increase was not significant. On enrichment, over 15% of sandwiches contained Listeria species. L. innocua and L. monocytogenes were the only species isolated by plate count at numbers > or = 100 cfu/g (1.5% of total samples). Potentially hazardous levels of L. monocytogenes (defined as > or = 10(3) cfu/g) were found in two sandwiches examined (0.3%), indicating that although Total Viable Counts (TVCs) may often be high, the risk of listeriosis to vulnerable individuals from sandwiches is relatively low. It is important to distinguish the risk of consuming potentially hazardous levels of a pathogen in food from the risk of contracting illness as a result of such an event.     

黄曲霉毒素与原发性肝癌关系的研究

The AFB1 intake and the AFM1 excretion of 81 households in 10 villages, Guanxi were investigated using the ELISA method. The results showed that there was positive correlation between PLC mortality and AFB1 intake from corn and peanut oil, but not from rice. The results of stepwise regression showed that main factors were AFB1 intake of males, AFM1 excretion of females and consumption of corn. The results showed that aflatoxins were correlated with mortality rates of liver cancer. Further investigation needs to be carried out in case-control and cohort studies.     

Bacterial Populations in Complementary Foods and Drinking-water in Households with Children Aged 10-15 Months in Zanzibar, Tanzania

Bacteria were quantified in samples of drinking-water and in two porridges prepared for infant-feeding [fortified instant soy-rice porridge (SRP) and cooked porridge (Lishe bora, LB)] in 54 households. Bacterial numbers were measured again after the porridges had been held at room temperature for four hours (T4). Findings were benchmarked against bacterial numbers in traditional complementary foods sampled from 120 households. Total bacteria, coliform, and Enterobacteriaceae counts were enumerated using Petrifilm™. The mean log bacterial numbers were the lowest for LB at T0 (2.24±0.84 cfu/g aerobic counts) and the highest for SRP at T4 (4.63±0.56 cfu/g aerobic counts). The total bacteria, coliform and Enterobacteriaceae counts were higher at T4 than at T0 for LB (p≤0.001); however, only the coliform and Enterobacteriaceae counts were higher at T4 than at T0 for SRP (p<0.001). Drinking-water, SRP0, traditional foods, and SRP4 all had the mean aerobic counts higher than the acceptable cut-off but the total bacterial count in SRP0 was not significantly (p=0.543) different from drinking-water. However, coliform and Enterobacteriaceae counts in SRP0 were higher than in drinking-water (p<0.001). Also, although the aerobic counts of SRP4 were not significantly (p>0.999) different from traditional foods, the coliform and Enterobacteriaceae counts were significantly higher in SRP4 than in traditional foods (p<0.001). It is, therefore, recommended that food safety concerns be addressed when improving complementary foods.Key words: Bacteria, Coliform, Complementary foods, Enterobacteriaceae, Food safety, Water microbiology, Tanzania     

Determinants of aflatoxin levels in Ghanaians: sociodemographic factors, knowledge of aflatoxin and food handling and consumption practices

Aflatoxins are among the most potent of carcinogens found in staple foods such as groundnuts, maize and other oil seeds. This study was conducted to measure the levels of aflatoxin B(1) (AFB(1)) albumin adducts in blood and aflatoxin M(1) (AFM(1)) metabolite in urine of people in a heavy peanut and maize consuming region of Ghana and to examine the association between aflatoxin levels and several socio-demographic factors and food handling and consumption practices. A cross-sectional study was conducted in four villages in the Ejura Sekyedumase district of Ghana. A socio-demographic survey was administered to 162 participants. Blood samples were collected from 140 and urine samples from 91 of the participants and AFB(1) albumin-adduct levels in blood and AFM(1) levels in urine were measured. High AFB(1) albumin-adduct levels were found in the plasma (mean+/-SD=0.89+/-0.46pmol/mg albumin; range=0.12-3.00pmol/mg; median=0.80pmol/mg) and high AFM(1) levels in the urine (mean+/-SD=1,800.14+/-2602.01pg/mg creatinine; range=non-detectable to 11,562.36pg/mg; median=472.67pg/mg) of most of the participants. There was a statistically significant correlation (r=0.35; p=0.007) between AFB(1)-albumin adduct levels in plasma and AFM(1) levels in urine. Several socio-demographic factors, namely, educational level, ethnic group, the village in which participants lived, number of individuals in the household, and number of children in the household attending secondary school, were found to be significantly associated with AFB(1) albumin-adduct levels by bivariate analysis. By multivariate analyses, ethnic group (p=0.04), the village in which participants live (p=0.02), and the number of individuals in the household (p=0.01), were significant predictors of high AFB(1) albumin-adducts. These findings indicate strongly that there is need for specifically targeted post-harvest and food handling and preparation interventions designed to reduce aflatoxin exposure among the different ethnic groups in this region of Ghana.     

Some microbiological and biochemical studies on the fermentation of 'awaze' and 'datta', traditional Ethiopian condiments

The microbial and some biochemical changes during the fermentation of two Ethiopian condiments were studied. The aerobic mesophilic microflora of the ingredients of 'awaze' were dominated by Bacillus species (1.1 x 10(6) cfu/g) and lactic acid bacteria (4.5 x 10(4) cfu/g). The counts of aerobic mesophilic bacteria declined during the fermentation period. Lactic acid bacteria (LAB) reached the maximum count of 5.9 x 10(9) cfu/g at day 4 and the count remained > 10(8) cfu/g throughout the fermentation. The heterofermentative LAB dominated until day 3; thereafter the homolactics dominated the fermentation. Yeasts appeared at day 6 and increased to 2.5 x 10(6) cfu/g. In 'datta' fermentation, the count of aerobic mesophilic bacteria remained unchanged during the fermentation. LAB initiated the fermentation at a level of 7.1 x 10(4) cfu/g and reached 1.2 x 10(9) cfu/g at day 7. The homolactic LAB initiated and dominated the fermentation for the first 2 days and the heterolactics took over thereafter. Both fermentations were accompanied by declining pH and increasing titratable acidity. Salmonella typhimurium was inhibited during both fermentations within 48 h. Both 'awaze' and 'datta' had low initial contents of available protein and reducing sugars and these did not show marked differences throughout the fermentation.