Aflatoxins (AFs) are considered to play important functions in species of Aspergillus section Fla... more Aflatoxins (AFs) are considered to play important functions in species of Aspergillus section Flavi including an antioxidative role, as a deterrent against fungivorous insects, and in antibiosis. Atoxigenic Flavi are known to degrade AF-B1 (B1). To better understand the purpose of AF degradation, we investigated the degradation of B1 and AF-G1 (G1) in an antioxidative role in Flavi. Atoxigenic and toxigenic Flavi were treated with artificial B1 and G1 with or without the antioxidant selenium (Se), which is expected to affect levels of AF. After incubations, AF levels were measured by HPLC. To estimate which population would likely be favoured between toxigenic and atoxigenic Flavi under Se, we investigated the fitness, by spore count, of the Flavi as a result of exposure to 0, 0.40, and 0.86 µg/g Se in 3%-sucrose cornmeal agar (3gCMA). Results showed that levels B1 in medium without Se were reduced in all isolates, while G1 did not significantly change. When the medium was treated w...
Fungi contaminate various crops worldwide. Maize, an important human staple and livestock cereal,... more Fungi contaminate various crops worldwide. Maize, an important human staple and livestock cereal, is susceptible to contamination with fungi in the field.
a International Institute of Tropical Agriculture (IITA-Zambia), Lusaka, Zambia b IITA-Ibadan, Oy... more a International Institute of Tropical Agriculture (IITA-Zambia), Lusaka, Zambia b IITA-Ibadan, Oyo Road, Ibadan, Nigeria c Zambia Agriculture Research Institute, Mount Makulu Central Research Station, Zambia. d National Institute for Scientific and Industrial Research (NISIR), Lusaka, Zambia e The World Vegetable Center (AVRDC) Eastern and Southern Africa , Duluti, Arusha, Tanzania f USDA-ARS, School of Plant Sciences, University of Arizona, Tucson, USA.
a Deutsche Gesellschaft für Internationale Zusammenar beit (GIZ), Germany b International Institu... more a Deutsche Gesellschaft für Internationale Zusammenar beit (GIZ), Germany b International Institute of Tropical Agriculture (II TA-Zambia), Lusaka, Zambia c IITA-Ibadan, Oyo Road, Ibadan, Nigeria d Zambia Agriculture Research Institute, Mount Makul u Central Research Station, Zambia. e National Institute for Scientific and Industrial Re search (NISIR), Lusaka, Zambia f The World Vegetable Center (AVRDC) Eastern and Sou thern Africa , Duluti, Arusha, Tanzania g USDA-ARS, School of Plant Sciences, University of Arizona, Tucson, USA.
The removal of silicic acid, calcium phosphate and the sesquioxides is essential for the producti... more The removal of silicic acid, calcium phosphate and the sesquioxides is essential for the production of high grade raw sugars. Silicic acid and calcium oxalates are the major compounds causing hard and difficult to remove scale in evaporators. This study investigated the extent to which scale forming ions could be removed from clarified sugarcane juice by electro-coagulation (electro-clarification) using a novel Kaselco reactor fed with DC current. Observations from the study indicate that electro-coagulation can remove essentially all the silica, reduces Ca, P, Mg and Al although to a lesser extent and adds some iron to the treated juice. The direct operating cost of an electro-coagulating unit was estimated at <0.02 cents per pound of raw sugar.
Food, which ensures the sustenance o f life, has also been implicated in the development or preve... more Food, which ensures the sustenance o f life, has also been implicated in the development or prevention o f numerous diseases including cancer. Cancer may be a result o f hereditary factors or genomic instability induced by DNA damage, from the intrinsic chemistry o f cells or extrinsic factors like aflatoxin Bt. Aflatoxin B„ produced by Aspergillus flavus and Aspergillus parasiticus, is a common contaminant o f com and cottonseed and a proven mutagen and animal carcinogen. Increased scientific knowledge and establishment o f regulation have reduced but not eliminated exposure to aflatoxin Bt. Complete elimination may be uneconomical for producers and may deprive consumers of sources o f nourishment. Consumption o f substances that offset the deleterious effects o f aflatoxin, particularly those intrinsic to a commonly consumed foodstuff, may circumvent the problem. This study set out to isolate, substances that possess antimutagenic activity from com and cottonseed. A bioassay direc...
<b>Copyright information:</b>Taken from "Aflatoxin Contamination of Commercial M... more <b>Copyright information:</b>Taken from "Aflatoxin Contamination of Commercial Maize Products during an Outbreak of Acute Aflatoxicosis in Eastern and Central Kenya"Environmental Health Perspectives 2005;113(12):1763-1767.Published online 10 Aug 2005PMCID:PMC1314917.This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI. Each dot represents the rate of aflatoxicosis by division, and dots are in the center of each division (divisions are not shown).
<b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxi... more <b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxicosis Outbreak, Kenya, 2004"Environmental Health Perspectives 2005;113(12):1779-1783.Published online 9 Aug 2005PMCID:PMC1314920.This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.
<b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxi... more <b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxicosis Outbreak, Kenya, 2004"Environmental Health Perspectives 2005;113(12):1779-1783.Published online 9 Aug 2005PMCID:PMC1314920.This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.
In April 2004, one of the largest aflatoxicosis outbreaks occurred in rural Kenya, resulting in 3... more In April 2004, one of the largest aflatoxicosis outbreaks occurred in rural Kenya, resulting in 317 cases and 125 deaths. Aflatoxin-contaminated homegrown maize was the source of the outbreak, but the extent of regional contamination and status of maize in commercial markets (market maize) were unknown. We conducted a cross-sectional survey to assess the extent of market maize contamination and evaluate the relationship between market maize aflatoxin and the aflatoxicosis outbreak. We surveyed 65 markets and 243 maize vendors and collected 350 maize products in the most affected districts. Fifty-five percent of maize products had aflatoxin levels greater than the Kenyan regulatory limit of 20 ppb, 35 % had levels> 100 ppb, and 7 % had levels> 1,000 ppb. Makueni, the district with the most aflatoxicosis case-patients, had significantly higher market maize aflatoxin than did Thika, the study district with fewest case-patients (geometric mean aflatoxin = 52.91 ppb vs. 7.52 ppb, p...
OBJECTIVES: During January–June 2004, an aflatoxicosis outbreak in eastern Kenya resulted in 317 ... more OBJECTIVES: During January–June 2004, an aflatoxicosis outbreak in eastern Kenya resulted in 317 cases and 125 deaths. We conducted a case–control study to identify risk factors for contamination of implicated maize and, for the first time, quantitated biomarkers associated with acute aflatoxicosis. DESIGN: We administered questionnaires regarding maize storage and consumption and obtained maize and blood samples from participants. PARTICIPANTS: We recruited 40 case-patients with aflatoxicosis and 80 randomly selected controls to participate in this study. EVALUATIONS/MEASUREMENTS: We analyzed maize for total aflatoxins and serum for aflatoxin B1–lysine albumin adducts and hepatitis B surface antigen. We used regression and survival analyses to explore the relationship between aflatoxins, maize consumption, hepatitis B surface antigen, and case status. RESULTS: Homegrown (not commercial) maize kernels from case households had higher concentrations of aflatoxins than did kernels from...
aflatoxicosis outbreak in eastern Kenya resulted in 317 cases and 125 deaths. We conducted a case... more aflatoxicosis outbreak in eastern Kenya resulted in 317 cases and 125 deaths. We conducted a case-control study to identify risk factors for contamination of implicated maize and, for the first time, quantitated biomarkers associated with acute aflatoxicosis. DESIGN: We administered questionnaires regarding maize storage and consumption and obtained maize and blood samples from participants. PARTICIPANTS: We recruited 40 case-patients with aflatoxicosis and 80 randomly selected controls to participate in this study. EVALUATIONS/MEASUREMENTS: We analyzed maize for total aflatoxins and serum for aflatoxin B 1 -lysine albumin adducts and hepatitis B surface antigen. We used regression and survival analyses to explore the relationship between aflatoxins, maize consumption, hepatitis B surface antigen, and case status. RESULTS: Homegrown (not commercial) maize kernels from case households had higher concentrations of aflatoxins than did kernels from control households [ To select 40 pati...
Aflatoxins (AFs) are considered to play important functions in species of Aspergillus section Fla... more Aflatoxins (AFs) are considered to play important functions in species of Aspergillus section Flavi including an antioxidative role, as a deterrent against fungivorous insects, and in antibiosis. Atoxigenic Flavi are known to degrade AF-B1 (B1). To better understand the purpose of AF degradation, we investigated the degradation of B1 and AF-G1 (G1) in an antioxidative role in Flavi. Atoxigenic and toxigenic Flavi were treated with artificial B1 and G1 with or without the antioxidant selenium (Se), which is expected to affect levels of AF. After incubations, AF levels were measured by HPLC. To estimate which population would likely be favoured between toxigenic and atoxigenic Flavi under Se, we investigated the fitness, by spore count, of the Flavi as a result of exposure to 0, 0.40, and 0.86 µg/g Se in 3%-sucrose cornmeal agar (3gCMA). Results showed that levels B1 in medium without Se were reduced in all isolates, while G1 did not significantly change. When the medium was treated w...
Fungi contaminate various crops worldwide. Maize, an important human staple and livestock cereal,... more Fungi contaminate various crops worldwide. Maize, an important human staple and livestock cereal, is susceptible to contamination with fungi in the field.
a International Institute of Tropical Agriculture (IITA-Zambia), Lusaka, Zambia b IITA-Ibadan, Oy... more a International Institute of Tropical Agriculture (IITA-Zambia), Lusaka, Zambia b IITA-Ibadan, Oyo Road, Ibadan, Nigeria c Zambia Agriculture Research Institute, Mount Makulu Central Research Station, Zambia. d National Institute for Scientific and Industrial Research (NISIR), Lusaka, Zambia e The World Vegetable Center (AVRDC) Eastern and Southern Africa , Duluti, Arusha, Tanzania f USDA-ARS, School of Plant Sciences, University of Arizona, Tucson, USA.
a Deutsche Gesellschaft für Internationale Zusammenar beit (GIZ), Germany b International Institu... more a Deutsche Gesellschaft für Internationale Zusammenar beit (GIZ), Germany b International Institute of Tropical Agriculture (II TA-Zambia), Lusaka, Zambia c IITA-Ibadan, Oyo Road, Ibadan, Nigeria d Zambia Agriculture Research Institute, Mount Makul u Central Research Station, Zambia. e National Institute for Scientific and Industrial Re search (NISIR), Lusaka, Zambia f The World Vegetable Center (AVRDC) Eastern and Sou thern Africa , Duluti, Arusha, Tanzania g USDA-ARS, School of Plant Sciences, University of Arizona, Tucson, USA.
The removal of silicic acid, calcium phosphate and the sesquioxides is essential for the producti... more The removal of silicic acid, calcium phosphate and the sesquioxides is essential for the production of high grade raw sugars. Silicic acid and calcium oxalates are the major compounds causing hard and difficult to remove scale in evaporators. This study investigated the extent to which scale forming ions could be removed from clarified sugarcane juice by electro-coagulation (electro-clarification) using a novel Kaselco reactor fed with DC current. Observations from the study indicate that electro-coagulation can remove essentially all the silica, reduces Ca, P, Mg and Al although to a lesser extent and adds some iron to the treated juice. The direct operating cost of an electro-coagulating unit was estimated at <0.02 cents per pound of raw sugar.
Food, which ensures the sustenance o f life, has also been implicated in the development or preve... more Food, which ensures the sustenance o f life, has also been implicated in the development or prevention o f numerous diseases including cancer. Cancer may be a result o f hereditary factors or genomic instability induced by DNA damage, from the intrinsic chemistry o f cells or extrinsic factors like aflatoxin Bt. Aflatoxin B„ produced by Aspergillus flavus and Aspergillus parasiticus, is a common contaminant o f com and cottonseed and a proven mutagen and animal carcinogen. Increased scientific knowledge and establishment o f regulation have reduced but not eliminated exposure to aflatoxin Bt. Complete elimination may be uneconomical for producers and may deprive consumers of sources o f nourishment. Consumption o f substances that offset the deleterious effects o f aflatoxin, particularly those intrinsic to a commonly consumed foodstuff, may circumvent the problem. This study set out to isolate, substances that possess antimutagenic activity from com and cottonseed. A bioassay direc...
<b>Copyright information:</b>Taken from "Aflatoxin Contamination of Commercial M... more <b>Copyright information:</b>Taken from "Aflatoxin Contamination of Commercial Maize Products during an Outbreak of Acute Aflatoxicosis in Eastern and Central Kenya"Environmental Health Perspectives 2005;113(12):1763-1767.Published online 10 Aug 2005PMCID:PMC1314917.This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI. Each dot represents the rate of aflatoxicosis by division, and dots are in the center of each division (divisions are not shown).
<b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxi... more <b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxicosis Outbreak, Kenya, 2004"Environmental Health Perspectives 2005;113(12):1779-1783.Published online 9 Aug 2005PMCID:PMC1314920.This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.
<b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxi... more <b>Copyright information:</b>Taken from "Case–Control Study of an Acute Aflatoxicosis Outbreak, Kenya, 2004"Environmental Health Perspectives 2005;113(12):1779-1783.Published online 9 Aug 2005PMCID:PMC1314920.This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.
In April 2004, one of the largest aflatoxicosis outbreaks occurred in rural Kenya, resulting in 3... more In April 2004, one of the largest aflatoxicosis outbreaks occurred in rural Kenya, resulting in 317 cases and 125 deaths. Aflatoxin-contaminated homegrown maize was the source of the outbreak, but the extent of regional contamination and status of maize in commercial markets (market maize) were unknown. We conducted a cross-sectional survey to assess the extent of market maize contamination and evaluate the relationship between market maize aflatoxin and the aflatoxicosis outbreak. We surveyed 65 markets and 243 maize vendors and collected 350 maize products in the most affected districts. Fifty-five percent of maize products had aflatoxin levels greater than the Kenyan regulatory limit of 20 ppb, 35 % had levels> 100 ppb, and 7 % had levels> 1,000 ppb. Makueni, the district with the most aflatoxicosis case-patients, had significantly higher market maize aflatoxin than did Thika, the study district with fewest case-patients (geometric mean aflatoxin = 52.91 ppb vs. 7.52 ppb, p...
OBJECTIVES: During January–June 2004, an aflatoxicosis outbreak in eastern Kenya resulted in 317 ... more OBJECTIVES: During January–June 2004, an aflatoxicosis outbreak in eastern Kenya resulted in 317 cases and 125 deaths. We conducted a case–control study to identify risk factors for contamination of implicated maize and, for the first time, quantitated biomarkers associated with acute aflatoxicosis. DESIGN: We administered questionnaires regarding maize storage and consumption and obtained maize and blood samples from participants. PARTICIPANTS: We recruited 40 case-patients with aflatoxicosis and 80 randomly selected controls to participate in this study. EVALUATIONS/MEASUREMENTS: We analyzed maize for total aflatoxins and serum for aflatoxin B1–lysine albumin adducts and hepatitis B surface antigen. We used regression and survival analyses to explore the relationship between aflatoxins, maize consumption, hepatitis B surface antigen, and case status. RESULTS: Homegrown (not commercial) maize kernels from case households had higher concentrations of aflatoxins than did kernels from...
aflatoxicosis outbreak in eastern Kenya resulted in 317 cases and 125 deaths. We conducted a case... more aflatoxicosis outbreak in eastern Kenya resulted in 317 cases and 125 deaths. We conducted a case-control study to identify risk factors for contamination of implicated maize and, for the first time, quantitated biomarkers associated with acute aflatoxicosis. DESIGN: We administered questionnaires regarding maize storage and consumption and obtained maize and blood samples from participants. PARTICIPANTS: We recruited 40 case-patients with aflatoxicosis and 80 randomly selected controls to participate in this study. EVALUATIONS/MEASUREMENTS: We analyzed maize for total aflatoxins and serum for aflatoxin B 1 -lysine albumin adducts and hepatitis B surface antigen. We used regression and survival analyses to explore the relationship between aflatoxins, maize consumption, hepatitis B surface antigen, and case status. RESULTS: Homegrown (not commercial) maize kernels from case households had higher concentrations of aflatoxins than did kernels from control households [ To select 40 pati...
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