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1.
The mycoflora, moisture content and aflatoxin contamination of pigeon pea (Cajanus cajan (L.) Millisp) stored in jute sacks and iron bins were determined at monthly intervals for a year. The predominant fungi on freshly harvested seeds wereAlternaria spp.,Botryodiplodia theobromae, Fusarium spp. andPhoma spp. These fungi gradually disappeared from stored seeds with time and by 5–6 months, most were not isolated. The fungi that succeeded the initially dominant ones were mainly members of the generaAspergillus, Penicillium andRhizopus. Population of these fungi increased up to the end of one year storage. Higher incidence of mycoflora andAspergillus flavus were recorded in jute-sack samples throughout the storage period. The moisture content of stored seeds was found to fluctuate with the prevailing weather condition, being low during the dry season and slightly high during the wet season. The stored seeds were free of aflatoxins for 3 and 5 months in jute sacks and iron bins respectively. The level of aflatoxins detected in jute-sack storage system was considerably higher than that occurring in the iron bin system. Of 196 isolates ofA. flavus screened, 48% were toxigenic in liquid culture (54% from jute sacks and 41% from iron bins).  相似文献   
2.
The growth of a toxigenic Aspergillus flavus decreased progressively with increasing concentration of essential oils from leaves of Azadirachta indica , Morinda lucida and seeds of A. indica incorporated into SMKY liquid medium. The oils also significantly reduced aflatoxin synthesis in inoculated maize grains. Oils from A. indica seeds completely suppressed aflatoxin synthesis in inoculated maize at 500 and 1000 ppm while those of M. lucida also showed complete inhibition at 1000 ppm.  相似文献   
3.
Sclerotium rolfsii Sacc. is an important fungal pathogen affecting the production of tomato (Lycopersicon esculentum Mill.). Conventional control methods using chemicals are expensive, which constitute environmental hazards. This has necessitated the search for alternatives in botanicals. Ethanol and supernatant solution of fermented maize slurry extracts from Ocimum gratissimum, Cymbopogon citratus, Xylopia aethiopica, Aframomum melegueta and Allium sativum were evaluated. In vitro test was carried out at 1, 2, 3, 4 and 5% concentrations against the pathogen. Mycelial growth was significantly reduced in the following descending order: O. gratissimum?>?A. melegueta?>?A. sativum?>?X. aethiopica?>?C. citratus. Supernatant solution extracts of O. gratissimum and A. melegueta at 5% concentration gave highest mycelial reduction (0.00?mm), respectively, while O. gratissimum ethanol extract recorded highest mycelial reduction (0.23?mm) among the ethanol extracts. Supernatant solution of fermented maize slurry extracts of O. gratissimum and A. melegueta at 5% concentration was more effective in reducing mycelial growth of S. rolfsii.  相似文献   
4.
The microbial composition of the frass from maize (Zea mays) grains and seven dried root and tuber crops (R&TC) infested by Prostephanus truncatus were evaluated. Five cubes (6 cm3) of each R&TC as well as 100 g of maize grains were separately infested with 15 pairs of 1–2 day old adult LGB in 250 cm3 sized Kilner jars and incubated for 90 days at 28 ± 1°C and 79–82% RH. At 90 days post-infestation, the microbiological assay of frass from the commodities was performed. The results indicated the presence of 10 bacterial species, namely Bacillus cereus, B. macerans, Proteus mirabilis, P. morganic, P. rettgeri, Proteus sp., Pseud geniculatum, Pseud fragii, Pseud putela, Serratia marcences and six fungal species, namely Aspergillus niger, A. tamari, A. parasiticus, A. ochraceus, Fusarium compacticum and F. oxysporum. Infested cubes of M. esculenta have the highest population of adult LGB (168.3) and frass from its damaged cubes had the highest mean bacterial count of 30.0 × 107 colony forming units (CFU) and it was significantly (P < 0.05) higher than LGB infestation and bacterial infection of other R&TC. The bacterial count from the damaged commodities correlated positively and significantly (P < 0.05) with weight of frass, percentage damage and percentage weight loss. The results revealed that frass from the LGB-infested and damaged commodities were infected by bacteria and fungi. Maize grains and dried R&TC should therefore be protected from LGB infestation to avoid quantity reduction and microbial infection.  相似文献   
5.
The selective oxidation of aryl substrates to chiral cis-1,2-dihydrodiols is an industrially important reaction for the production of intermediates that can be used to produce fine chemicals, pharmaceuticals, and many other bioactive natural products. More specifically, the oxidation of naphthalene to produce optically pure (+)-cis-(1R,2S)-1,2-napthalene dihydrodiol (NDHD) to be used as a chiral synthon for specialty chemicals has gained much interest. Escherichia coli JM109(DE3) pDTG141 expresses naphthalene dioxygenase which catalyzes this reaction. Poor substrate solubility and substrate toxicity are barriers to using the power of these enzymes in large-scale aqueous whole cell systems. A biphasic reaction system was chosen to overcome these barriers. The optimal biphasic conditions for E. coli JM109(DE3) pDTG141 were determined to be 20% dodecane as the organic solvent containing 40 g/L naphthalene. The productivity of the biotransformation using resting cells was 1.75 g-diol/g-cdw/h for the first 6 h with 20% organic phase, which was increased from 0.59 g-diol/g-cdw/h for growing cells with 40% organic phase. The biocatalytic activity was retained for at least 12 h. The biocatalyst could be recycled for at least four runs in both suspended and immobilized form. The stability of the 12 h recycle was improved by immobilization in calcium alginate beads. The process has been improved both environmentally and economically by reducing the amount of solvent used and by recycling the biocatalyst.  相似文献   
6.
This study used data from a community-based survey to examine women's experiences of abortion in Nigeria. Fourteen percent of respondents reported that they had ever tried to terminate a pregnancy, and 10% had obtained an abortion. The majority of women who sought an abortion did so early in the pregnancy. Forty-two percent of women who obtained an abortion used the services of a non-professional provider, a quarter experienced complications and 9% sought treatment for complications from their abortions. Roughly half of the women who obtained an abortion used a method other than D&C or MVA. The abortion prevalence and conditions under which women sought abortions varied by women's socio-demographic characteristics. Because abortion is illegal in Nigeria except to save the woman's life, many women take significant risks to terminate unwanted pregnancies. Reducing the incidence of unwanted pregnancy and unsafe abortion can significantly impact the reproductive health of women in Nigeria.  相似文献   
7.
A simple and rapid method is described for the detection of amylase-producing micro-organisms on solid media using Remazol Brilliant Blue-starch as substrate. The blue starch is incorporated into nutrient agar and amylase production is detected by the disappearance of the colour around the colonies. The method which is non-destructive, allows for direct visualization and isolation of amylolytic micro-organisms from the environment without prior replication of colonies.  相似文献   
8.
Mycotoxins, toxic secondary metabolites of fungi are now recognised as major cause of food intoxications in Sub Saharan Africa (SSA). Aflatoxins, the most important of the group have been implicated in acute aflatoxicoses, carcinogenicity, growth retardation, neonatal jaundice and immunological suppression in SSA. The hot and humid tropical climate provides ideal condition for growth of toxigenicAspergillus spp, making food contamination to be widespread in SSA, with maize and groundnuts being the most contaminated. The available data suggests that cassava products (the most important African food) are not prone to aflatoxin contamination. Recent data on ochratoxin A produced by species ofAspergillus on grains have indicated the necessity for it to be monitored in SSA. Fumonisins represent the most importantFusarium mycotoxins in SSA, and surveillance data indicate very high contamination rates of almost 100% in maize samples from West Africa. Limited information exists on the occurrence of trichothecenes, while the data currently available suggest that zearalenone contamination seems not to be a problem in SSA. The strategies under investigation to mitigate the mycotoxin problem in SSA include education of the people on the danger of consuming mouldy foods, pre and post harvest management strategies with emphasis on biological control, use of plant products to arrest fungal growth during storage, enterosorbent clay technology, and the search for traditional techniques that could reduce/detoxify mycotoxins during food processing.  相似文献   
9.
BackgroundIn Uganda, abortion is permitted only when the life of a woman is in danger. This restriction compels the perpetuation of the practice in secrecy and often under unsafe conditions. In 2003, 294,000 induced abortions were estimated to occur each year in Uganda. Since then, no other research on abortion incidence has been conducted in the country.MethodsData from 418 health facilities were used to estimate the number and rate of induced abortion in 2013. An indirect estimation methodology was used to calculate the annual incidence of induced abortions ─ nationally and by major regions. The use of a comparable methodology in an earlier study permits assessment of trends between 2003 and 2013.ResultsIn 2013, an estimated 128,682 women were treated for abortion complications and an estimated 314,304 induced abortions occurred, both slightly up from 110,000 and 294,000 in 2003, respectively. The national abortion rate was 39 abortions per 1,000 women aged 15–49, down from 51 in 2003. Regional variation in abortion rates is very large, from as high as an estimated 77 per 1,000 women 15–49 in Kampala region, to as low as 18 per 1,000 women in Western region. The overall pregnancy rate also declined from 326 to 288; however the proportion of pregnancies that were unintended increased slightly, from 49% to 52%.ConclusionUnsafe abortion remains a major problem confronting Ugandan women. Although the overall pregnancy rate and the abortion rate declined in the past decade, the majority of pregnancies to Ugandan women are still unintended. These findings reflect the increase in the use of modern contraception but also suggest that a large proportion of women are still having difficulty practicing contraception effectively. Improved access to contraceptive services and abortion-related care are still needed.  相似文献   
10.
A patient found to have ectopic Cushing's syndrome three months after surgical resection of cloacogenic carcinoma of the anal canal was studied with serial plasma cortisol and ACTH measurements. The effects of therapy on plasma ACTH and cortisol levels were noted. An autopsy was performed immediately after death and liver metastatic tumor tissue was assayed for "small" ACTH, "big" ACTH, PTH, and alpha sub-unit of hCG, Clinical Cushing's syndrome was observed along with nonsuppressible plasma cortisol level. Plasma ACTH only reached the highest normal level but tumor ACTH ("small"), "big" ACTH, alpha sub-unit and PTH were markedly elevated. It was concluded that a case of classic cloacogenic carcinoma of the anal canal produced ectopic Cushing's syndrome. Elevated tumor alpha sub-unit and PTH were not associated with appreciable biologic activity. Ectopic Cushing's syndrome in this disease may imply poorer prognosis.  相似文献   
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