Browsing by Author "Okechukwu, R. I."

Now showing 1 - 3 of 3
  • Thumbnail Image
    ItemOpen Access
    Bacterial quality of rainwater in selected communities in Imo State, Nigeria
    (UP, 2006-06) Okereke, J. N.; Obasi, K. O.; Obiekezie, S. O.; Okechukwu, R. I.
    Muitas comunidades rurais do estado de Imo, Nigéria oriental, não têm acesso à água potável, sendo que a á gua da chuva tem sido sua principal fonte. Neste estudo, foram determinados os níveis bacterianos da á gua da chuva em três comunidades, Umunumo, Egbema e Ihiagwa. As amostras foram colhidas direta mente de telhados de zinco, telhados de sapê e telhados de amianto em diferentes períodos de chuva, mês de maio (começo das chuvas), mês de julho (pico das chuvas) e outubro (final das chuvas). A água acumulada de telhados de zinco da comunidade de Umunumo também foi examinada. O nível bacteriano foi alto no começo das chuvas nas amostras coletadas nos telhados de sapê, sendo seu maior valor em Egbema (7,4 x 103 cfu/100 ml). Os níveis de coliformes totais e coliformes fecais ( °6± ² ³«´ µG¶G² ³ ¶G·•² ¸ ¹ ) tiveram picos no começo das chuvas, 10 – 36 cfu/100 ml e 1 – 5 cfu/100 ml, respectivamente. Também nos reservató rios subterrâneos a contagem total de bactérias, coliformes totais e coliformes fecais totais foi muito elevada. As amostras estudadas dos meses de julho (pico) e outubro (final) de todas as comunidades estavam dentro do padrão de qualidade de água potável da OMS. Usando um modelo estatístico (para a = 0.05), a hipó tese nula foi rejeitada para os métodos e o período da coleta, enquanto que o local de coleta foi aceito. Portanto, apenas o período e o método de coleta das águas das chuvas afetam os níveis bacterianos
  • Thumbnail Image
    ItemOpen Access
    Comparative evaluation of ethanol production from sweet potato (lpomoea Batalas) and maize (Zea Mays)
    (Academic and Scientific Research Institute Publication, 2010) Okereke, J. N.; Okeke, O. A.; Okechukwu, R. I.
    Comparative evaluation of ethanol production was carried out with sweet potato (Red and \\'hile Species) and Maize sourced from National Root Crop Research Institute (NRCRI), Umudikc a:1d National Seed Centre (NSC), Umudikc. About 200g (in powered form) of peeled, sliced, drkl; and ground samples of sweet potato, and maize were subjected to complete hydrolysis using /\z.ha ·, 1981 method. The filtrates (hydrolysates) from hydrolysis were later subjected to lcrmentatim1 process using Saccharomyce cerevisiae for 72-96 hours. Distillation was adopted to recover ethanol produced at 78°C. The average volume of ethanol produced from Red Potato, white potato and maize were 28.40ml, 30.00ml and 37.17ml respectively. Ethanol from maize had pl I value nr 3.6; Red potato, 4.0; White, 4.3. Percentage yield of ethanol was in the order: Maizc>White potato> Red potato as their values were 14.72%, 11.93% and I Ll9% respectively. The results showed that maire had the highest sugar content thus, highest percentage yield of ethanol
  • Thumbnail Image
    ItemOpen Access
    Effect of different concentrations of sucrose, glucose and fructose on microtuberization of sweet potato (Ipomoea Batatas)
    (U. P, 2012-06) Okereke, J. N.; Nnoli, M. C.; Okechukwu, R. I.
    The effect of different concentrations of sucrose, glucose and fructose on in vitro microtuberization of sweet potato (Iponwea Nitwits) was studied. Plantlets were obtained from explants excised from mother tubers of sweet potato and cultured on Murashige and Stoog (MS) media without growth regulators. Growth characteristics after three weeks revealed that plantlets developed roots within 12 hours with lengths of 20-38cm; and developed shoots within 3-5 days with plantlet heights of 12-16. 5cm. Also, the number of leaves per plantlet was 5-20 and the nodal number was 12-1.4 per plantlet. Microtubers were formed from plantlets cultured on 3%, 5% and 8% concentrations of the three sugars as basic. carbon sources; with 5% and 8% concentrations yielding the biggest sizes of microtubers. This implies that concentrations of sucrose, glucose and fructose ranging between 3% and 8% are capable of forming sweet potato microtubers in vitro, hence facilitating mass production of microtubers which can be supplied to farmers at subsidized rate