Viscometric Studies on the Biodegradation of Some Vegetable Oils using Aspergillus Niger

The continual utilization of vegetable oils in homes, restaurants, hotels and cosmetic industries require their preservation against microorganisms. Aerobic biodegradation of four different seed oils were carried out using Aspergillus niger in order to determined their susceptibility to these common microbes in a temperate climate. The intrinsic viscosities of the inoculated oils, incubated at temperature of 35oC, were determined from the relative viscosities measured at intervals of seven days for six weeks. The viscosities of the un-inoculated oils were determined and used as control. A gradual increase in the viscosities with increase in the time of incubation was observed. This was ascribed to the possible growth of the microbes as they consume the smaller molecules formed during the break down of the oil. A remarkable change in the colour of the oils sample was noticed. This was then attributed to break down of compounds responsible for colours in these oils. The maximum viscosity values were obtained on the twenty eight day of incubation beyond which a decline was observed.  This was credited to the formation of secondary metabolites. The Fourier Transform- Infra Red spectrogram and the pH supported the secretion of enzymes and subsequent conversion of oil to secondary metabolites by the Aspergillus niger.  Absorption peaks at 2923.04-2930.09cm-1 and 3359.14-3429.69 cm-1 were due to hydroxyl and carboxyl groups in the biodegraded compounds. Edible oils with high free fatty acid value would therefore, biodegrade easily if contaminated by common fungi such as Aspergillusniger at temperature of 35oC.  The consumption of edible oil without frying commonly practiced in Nigeria may have been the source of diseases such as diarrhea, flu, vomiting, etc. It is recommended that edible Oils such as Palm, Ground nut, Cotton seed oil should be stored at temperature below 30oC and properly covered to prevent any contact with fungi. Keywords: Oil, Biodegradation, Aspergillus niger, Viscosit

Water Quality Assessment of Some Selected Hand Dug Wells and a Borehole in North Eastern Parts of Bauchi Metropolis, Nigeria

Water samples were taken from six hand dug wells and a borehole for physico-chemical and microbial analysis to ascertain its quality, type and suitability for domestic, livestock and irrigation purposes. The ranges of results of the physico-chemical parameters are: temperature (28-31.5)oC, Conductivity (170-650)µs/cm, turbidity (1.0-90.8)NTU, and pH(7.0-8.5). Other chemical parameters include: cations -  Ca2+(25.6 – 72.0)mg/l , Na+(23.1 – 75.87)mg/l, K+(0.14 – 78.3)mg/l, Mg2+(1.46 – 20.75)mg/l, Fe2+(0.0 – 1.1)mg/l, Cu2+(0.0 – 0.49)mg/l, Zn2+(0.00 – 1.74)mg/l, Pb2+(0.00 – 0.001)mg/l, Cr6+(0.00 – 0.02)mg/l and anions – HCO3-(54.0 – 140.0)mg/l, Cl-(32.5 – 114.96)mg/l,  F-(0.23 – 0.77)mg/l,  CO32-(32.4 – 84.0)mg/l, SO42-(10.31 – 121.0)mg/l,  NO3-(1.08 – 75.7)mg/l, NO2-(0.013 – 0.69)mg/l. Data values analyzed from the results obtained indicate the water to be Ca-HCO3, K-HCO3, Mg-HCO3 and Na-Cl water type containing high concentrations of some major, minor and trace cations and anions which fall above the maximum permissible limits of the National Standard for Drinking Water Quality (NSDWQ) of Nigerian Industrial Standard (NIS), 2007. Physical and microbiological parameters indicate that the water is turbid and contain a high total coliform counts above the NIS set standards for maximum permissible limits. This may be attributed to proximities of soakaways and dumpsites to the wells which may need to be monitored from time to time. The water was also found to be suitable for irrigation. Keywords: Water Quality, Water Type, Irrigation Wate

Geochemometric approach to groundwater quality and health risk assessment of heavy metals of Yankari Game Reserve and its environs, Northeast Nigeria

A popular eco-tourist destination happy haven, renowned for its distinctive groundwater springs, wildlife population and endowed with notable archeologic monuments and other appealing characteristics, thus the need for a baseline survey of the physiochemical measurements to ascertain the concentrations of major cations and heavy metals (Cd, Co, Cr, Cu, Fe, Li, Mn, Ni, and Pb)), their distribution across the sampling locations and to investigate the origin of Potentially Toxic Elements (PTEs) due to threats from anthropogenic and geogenic processes to its quality to evaluating its suitability for drinking, and the risk imposed on human health through the use of Water Quality Index (WQI), Hazard Quotient (HQ) and Hazard Index (HI). Concentrations of forty-one water samples from twenty natural springs, fifteen boreholes, five hand-dug wells, and a stream a were detected. Nine heavy metals (Fe, Mn, Li, Cd, Co, Cr, Cu, Pb, and Ni) were analysed with Flame Atomic Absorption Spectrometry (FAAS) and the data using different multivariate statistical approaches. Five component types; 24.40%, 14.50%, 12.10%, 9.64% and 9.24% extracted accounted for 69.79% total variance. The dominant variables derived from PCA's five components indicated the influence of the weathering of anhydrous carbonate, which released major cations and the PTEs. Calculated HQs and HI for adults and children were generally less than one (HQ 1, for children ingesting water from all the water sources. Hand-dug wells and surface water from the stream had HQ and HI > 1 for Cd for adults, which may not be harmful but with overtime exposure and may require monitoring; otherwise, it may pose more threats to adults and children with time

Groundwater pollutants characterization by geochemometric technique and geochemical modeling in tropical savanna watershed

Multiple interactions of geogenic and anthropogenic activities can trigger groundwater pollution in the tropical savanna watershed. These interactions and resultant contamination have been studied using applied geochemical modeling, conventional hydrochemical plots, and multivariate geochemometric methods, and the results are presented in this paper. The high alkalinity values recorded for the studied groundwater samples might emanate from the leaching of carbonate soil derived from limestone coupled with low rainfall and high temperature in the area. The principal component analysis (PCA) unveils three components with an eigenvalue > 1 and a total dataset variance of 67.37%; this implies that the temporary hardness of the groundwater and water–rock interaction with evaporite minerals (gypsum, halite, calcite, and trona) is the dominant factor affecting groundwater geochemistry. Likewise, the PCA revealed anthropogenic contamination by discharging SO42-,NO3-,Cl- and K + from agricultural activities and probable sewage leakages. Hierarchical cluster analysis (HCA) also revealed three clusters; cluster I reflects the dissolution of gypsum and halite with a high elevated load of NO3- released by anthropogenic activities. However, cluster II exhibited high KHCO32- and KCl- loading in the groundwater from weathering of bicarbonate and sylvite minerals. Sulfate (SO42-) dominated cluster III mineralogy resulting from weathering of anhydrite. The three clusters in the Maiganga watershed indicated anhydrite, gypsum, and halite undersaturation. These results suggest that combined anthropogenic and natural processes in the study area are linked with saturation indexes that regulate the modification of groundwater quality