Annual Research & Review in Biology

Fruits and vegetables are important in human diets as they help the body system function optimally but could also pose risk to human health when taken unhygienically. This study assessed geohelminths contamination on some common fruits and vegetables sold in Lafia markets and also obtained information on people’s knowledge about fruits and vegetables contamination with geohelminth parasites using structured questionnaire. A total of 500 samples of fruits and vegetables (comprising 250 fruits and 250 vegetables) including mango, cashew, carrot, garden egg, tomato, fluted pumpkin, cabbage, lettuce, spinach and bitter leaf were sampled from five different markets in Lafia, Nasarawa state, Nigeria from May to July 2015. The studied samples were categorised into two; this include 300 washed and 200 unwashed samples. These samples were checked for geohelminths contamination using standard floatation and sedimentation techniques. Cabbage (Brassica oleracea) and fluted pumpkin (Telfairia occidentalis) had the highest proportion of geohelminths contamination (30.43%), lettuce (17.39%) and bitter leaf had no contamination among the vegetables sampled; however, contamination occurred highest in carrot (Daurus carota) (34.48%) within the fruit category and least contamination was found in tomato and cashew (20.69%). Geohelminth parasites eggs and larvae identified include Ascaris lumbricoides, Hookworm, Strongyloides stercoralis and Trichuiris trichiura with A. lumbricoides occurring highest. Information obtained indicated that 65% of the respondents have never heard of geohelminth parasites. Effective health and hygiene education is necessary in order to overcome the continued spread of geohelminths infections through eating unhygienic fruits and vegetables.

The textile industries wastewater is one of the most serious sources of environmental pollution due to presence of the textile dyes. In the present study, five bacteria and three fungi were isolated on Mineral Salt Medium (MSM) supplemented with 200 mg/l of Direct Blue 71 azo dye. The most active isolate was identified by 18S-rRNA gene sequencing method as Saccharomyces cerevisiae. The decolorization and degradation of Direct Blue 71 azo dye by S. cerevisiae was investigated in presence and absence of nano-scaled zero-valent iron (NZVI). The metabolic pathway of the dye degradation was elucidated using GC/MS analysis to identify the metabolites. This procedure was supported by enzymes assay and bioinformatics analysis. Dye-decay curves showed 96% dye removal after 72 hr. in absence of the catalyst; while it was 100% after 48 hr. in presence of 0.1% NZVI. High efficiency to decolorize Direct Blue71 enables this yeast to be used in biological treatment of industrial effluent containing such azo-dyes.

It is evident that high heavy metal concentrations in sediments are eventually magnified along the aquatic lives like fish hence affecting human health. The present study therefore sought to determine the concentration of some heavy metals in sediments and liver of Wild African Catfish (Clarias gariepinus) in Lake Kanyaboli, Kenya. Fish were collected with the aid of a gill net of mesh size 4” and 5” whereas bottom sediments were collected by ErkMan crab sampler. The concentrations of Cadmium, Chromium, Zinc, Copper, and Lead in lake sediment and in the liver of Clariasgariepinus were determined using Flame Atomic Absorption Spectrophotometry (FAAS). Mean differences were determined using ANOVA and separation of means with Tukey’s test. Correlation analysis was done to determine the relationship of heavy metal contamination in sediments and fish liver. Obtained results showed that mean metal concentration in sediments were Cd (0.49 ± 0.02 - 0.77 ± 0.02), Cr (4.26 ± 0.015 - 7.48 ± 0.042), Zn (79.61 ± 0.57 - 87.09 ± 1.01), Cu (14.03 ± 0.05 - 20.43 ± 0.55) and Pb (14.38 ± 0.96 - 155.56 ± 0.21). Metals concentrations were significantly (p < 0.05) higher in station 2 than at the other stations. The mean heavy metal concentrations in Clarias gariepinus liver were Cd (nd- 0.22 ± 0.01), Cr (0.37 ± 0.01 - 1.67 ± 0.03), Zn (7.12 ± 0.03 - 13.40 ± 0.32), Cu (2.12 ± 0.12 - 4.16 ± 0.12) and Pb (1.63 ± 0.33 - 14.40 ± 0.58). Zn exhibited a significant difference between the stations. Pearson’s correlation coefficient revealed positive correlation between heavy metals in sediments and fish liver except for Pb - Cd (r = -0.638; p = 0.849), Pb - Zn (r = - 0418; p = 0.689) and Pb - Cu (r = -0.461). The study concluded that Lake Kanyaboli contained elevated levels of heavy metals probably due to anthropogenic activities. Consequently, activities that cause the contamination should be discouraged by the suitable governmental agencies.

The Olero creek Zooplankton was sampled in wet season from 13 stations across a conductivity range of 150 µmhos to 8000 µmhos. The abundance of Copepods, some Cladocerans (Daphnia sp. and Ceriodaphna sp.) and Rotatoria did not vary together with conductivity in a correlation analysis. Correlation was high (p<0.05) only among the Cilliata where abundance of Opecularia sp. and Vorticella sp. were closely related to variations in conductivity values while Opisthostyla sp. exhibited marginal correlation with values of conductivity. However, among Rotatoria abundance variable for Brachionus sp., Euchlanis sp., Notholca sp. and Asplanchna sp. was not explained by variations of single variable of conductivity. The occurrence of only three genera of Cladocera, three genera of Cilliata and four genera of Rotatoria with relatively lower abundances than Copepod group recorded, suggest in this tidal creek the non- significance of freshwater Zooplankton. The diversity values were low ranging from 0.7 to 1.3 in addition to low evenness ranging from 0.1 to 0.2 across all stations. Copepods dominated by 92% followed by Rotatoria 3%; Cladocerans 1.2% and Cilliata 0.5%. The observed non-equilibrium in abundance of Copepods with significant low numbers of Rotatoria, Cladocerans and Cilliata suggest biological interactions that support ecological principles of a trophic cascade. The low numerical abundance of Ciliates was in sharp contrast to their ubiquity, rapid reproductive rate and capacity to survive in extreme environments, including adaption to anaerobic conditions. This fact provided surrogate information of a cascade effect and intraguild competition. The observed numerical relationship within trophic levels shows that top-level consumers (copepods) were operating a top-down system driven by predation and competition. The top-down cascading of this inverse correlation in numerical density between copepods and other zooplankton should be included in directions of future research. A more appropriate basis of cross system explanation of top down trophic cascades in many natural systems is required for marine, estuaries and freshwater systems.

Data on the contributions of indigenous knowledge of gorilla (Gorilla gorilla diehli), chimpanzee (Pan troglodytes ellioti) and buffalo (Syncerus caffer) to conservation, in the Black Bush Area of Waindow (BBAW): Menchum south, North West Region of Cameroon, was collected from August to October 2013. The general objective of the research was to establish elicit information on the indigenous knowledge of gorilla, chimpanzee and buffalo which can contribute to their conservation in the study site. Research data were obtained through an interviewer-administered questionnaire survey in five (5) hills of the study site (Attue, Itiaku, Akalieu, Njouhchou and Toukechiachia), purposively selected based on the presence of hunting camps within the hills. Indigenous knowledge systems, such as, cultural laws and regulations, gender in hunting wildlife and traditional beliefs / taboos, greatly influences the conservation of these species in the study area. Gorilla, chimpanzee and buffalo meat or body parts were in high demanded for food, medicinal and ritualistic purposes resulting to excessive poaching. Therefore, it is necessary to encourage active community participation, since some of the indigenous knowledge practices placed the remaining species of gorilla, chimpanzee and buffalo under intense threat of disappearing.

Nutrient enrichment of aquatic ecosystem can lead to increase in algae and aquatic plants and the loss of component species and ecosystem function. The aim of this study was to investigate the relationship of temperature and pH to nutrient uptake from nutrient media by immobilized cells of Pseudomonas aeruginosa. The study, which was carried out under shaking flask conditions used sodium alginate, agar-agar and agarose immobilized. The incubation temperatures used for the study were 25°C, 35°C and 45°C while the pH were 6,8 and 10. Just before inoculation and every 24 h, for 120 h, aliquot samples were aseptically withdrawn from each flask for the estimation of phosphate and sulphate concentrations in the media, using standard procedures. The results revealed maximum decreases in phosphate and sulphate concentrations in the media in presence of the immobilized cells occurred at 25°C and 35°C, respectively. In presence of the alginate-immobilized cells, lowest phosphate decreases from the initial concentration of 71.1 mg/L to 50.1 mg/L, 50.6 mg/L and 46.8 mg/L, after 96 h incubation were observed at incubation temperatures of 25°C, 35°C and 45°C, respectively. There was however no significant between phosphate concentrations in the media at the different incubation temperatures in presence of the alginate-immobilized cells. For sulphate uptake, in presence of the alginate-immobilized cells, highest decrease was observed at incubation temperature of 35°C. At this temperature, remarkable decrease was observed from 24 h incubation till the end of incubation. Generally, the study showed optimum pH for sulphate removal by the cells to be 8. At pH 6 and 10, only slight decreases in sulphate levels were observed at the end of incubation in the presence of the immobilized cells. In presence of the alginate-immobilized cells, remarkable increases in sulphate levels were observed throughout the period of incubation. The study was able to give an insight into the phosphate and sulphate uptake efficiency of the immobilized cells of the test bacteria under the experimental conditions used for investigation.

This study was carried out in the dry season between the months of November 2013 and February 2014. The goal was to contribute to the conservation of mammals through the establishment of base line information on mammal population in Mbi Crater Game Reserve (MCGR). The recce- transect method was used during the inventory. Seven (7) recce of 0.5 km each and fourteen (14) line transects of 0.5 km long were surveyed within the reserve making a total effort of 11 km. One hundred and twenty eight (128) questionnaires were administered to the local population, twenty four (24) semi-structured interviews to households and eight (8) focus group discussions with local chiefs and notables to get local people’s perceptions about wildlife conservation in MCGR. Nine (9) species of medium sized mammals were recorded within the reserve. The family Bovidae was well represented. Bushbuck and blue duiker were the most abundant mammal species with an encounter rate of 1.09 and 0.73 signs/km respectively. Mammals had higher densities in the west and southwest section of the reserve because of low intensity of anthropogenic activities. Hunting was the most frequent anthropogenic activity recorded in the study area. Only 37.5% variation in the encounter rate of medium mammals was provoked by anthropogenic activities. A majority of respondents acknowledged the reserve was important because they depended on it for bush meat, medicinal plants, and water. Other respondents considered the reserve as a liability and complained of restricted access and constant raiding of their farms by monkeys from the reserve. A greater fraction of respondents declared the community was not involved in managing the reserve. We can generally recommend that the government adopts a participatory management approach, establishing a joint anti-poaching team and provide alternative sources of protein to local people to reduce unsustainable hunting in the reserve. The government should also establish a compensation mechanism for those whose crops are constantly raided by animals from the reserve and organize mass sensitization programs for local communities on the importance of wildlife conservation.