3,4 sử dụng Moringa oleifera trong khử trùng nước trong hữu của tất cả các mối nguy hiểm mà nguồn cung cấp nước có thể được tiếp xúc là ô nhiễm bởi các sinh vật gây bệnh. Khử trùng là một quá trình hóa học để loại bỏ các vi khuẩn gây bệnh từ môi trường. Hóa học các đại lý đã được sử dụng như khử gồm halogen, phenol, rượu, kim loại nặng, thuốc nhuộm, xà phòng và chất tẩy rửa, hợp chất amoniac, hydrogen peroxide, và nhiều chất kiềm và axit (Metcalf và Eddy, năm 1991). Phổ biến nhất trong số này là các hóa chất ôxi hóa, và clo là phổ biến nhất được sử dụng. Tuy nhiên, clo có vấn đề phân rã và giảm nồng độ như nước chảy qua hệ thống phân phối (Devarakonda, Dân dụng và môi trường nghiên cứu www.iiste.org ISSN 2224-5790 người (giấy) ISSN 2225-0514 Vol.3 (trực tuyến), số 8, 2013 6 et al, 2010). It also has the potential for forming carcinogenic and mutagenic disinfection by-products (DBPs) (Goveas, et al, 2010). Disinfectants and their by-products may also be associated with increased risks of cardiovascular diseases, cancers, and birth defects. Although such risks are low, Arbuckle et al., (2002); Bove et al., (2002); and Woo, et al., (2002) noted that associations with such diseases could not be ruled out. These, and the high cost of chlorine, especially in developing countries where it needs to be imported, makes it imperative to look for cheaper alternatives that are also environmentally friendly. Studies by Eilert, et al (1981); Suarez, et al (2003), Suarez, et al (2005), Fisch, et al (2004), Thilza, et al (2010), and Bukar, et al (2010) identified the presence of an active antimicrobial agent in Moringa oleifera seeds. Eilert et al (1981) identified 4α-4-rhamnousyloxy-benzyf-isothiocynate as an active antimicrobial agent in M. Oleifera. This is readily soluble to water at 1.3umol/l and is non-volatile. In a study using pure 4 α -4rhamnotyloxy-benzylsothiocynate isolated from defatted M. Oleifera seeds, the antimicrobial action of M. Oleifera was investigated on three bacteria species - Bacillus Subtilis (gram -ve) , Serratia Marcescens (gram -ve) and Mycobacterium Pheli. The result showed that B. Subtlis was completely inhibited by 56µmol/l and M. Pheli by 40 µ mol/l. Only partial inhibition was observed for S. Macesscens in the range of concentration considered. The effect of residual turbidity on the antimicrobial action of M. oleifera was also reported. Folkard (1989), using extract of M. Stenopetala, was able to achieve 90% reduction of Herpes simplex virus and Orf virus. Whereas re-growth of Serratia Marinatubra occurred at high dosage (800rng/l), no re-growth was observed at lower seed dosage. In each case, the initial sample turbidity was between 20 to 25 NTU with residual turbidities in the range of 3-8NTU. However, Jahn (1986) reported that residual turbidities greater than 100NTU was companied by bacterial removal of only 0-36%. Thilza, et al (2010) reported that Moringa leaf stalk extract had mild activities against E. coli and Entrobacter aerogenes. Bukar, et al (2010) also studied the antimicrobial activities of Moringa Seed Chloroform extract and Moringa Seed Ethanol extract. They found both to have inhibitory effects on the growth of E. coli and determined the Minimum Inhibitory Concentration (MIC) to be >4mg/ml. Thilza, et al (2010) using extract from Moringa leaf stalk, found that at dilutions of 1000mg/ml, 700mg/ml, 400mg/ml, and 200mg/ml, only mild activity against E. coli and Entrobacter Aerogenes was noticed. They also found that the highest activity was produced by E.Coli at 1000mg/ml which comparatively was less than that of the standard drug tetracycline (250mg/ml). Suarez et al (2003) had reported that Moringa seeds protein may be a viable alternative to chemicals commonly used as food preservatives or for water disinfection. Bichi, et al (2012a) has shown that its highest disinfection action was achieved with the use of de-fatted seed cake and extracting the active ingredients by aqueous extraction. Bichi, et al (2012b) also found that the optimal conditions for the extraction of the bioactive compounds to be 31 minutes mixing time, 85 rpm mixing speed and 3.25 mg/mL Moringa dosage. In another study, Bichi, et al (2012c) developed a kinetic model for the application of Moringa oleifera seeds extract in water disinfection and determined the coefficient of specific lethality (Ʌcw) for E. coli inactivation to be 3.76 L mg-1 min-1. The mode of attack of the Moringa seeds extract on the E.coli cell was explained as by rupturing the cell and damaging the intercellular components, when water dips in to the cell which causes it to swell more and burst leading to death.
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