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Diversity of Earthworms in Nnamdi Azikiwe University, Awka

Abstract

Studies reveal that not up to 50% of earthworm species have been described in the world and the understanding of earthworm diversity is finite in most countries including Nigeria. The study was aimed at evaluating the diversity of earthworms and environmental factors affecting their abundance. Earthworms were collected from three (3) different sampling locations in Nnamdi Azikiwe University, Awka. Descriptive statistics and estimation of species abundance, dominance and diversity were used to analyze the data obtained from the study. From the study, four (4) species of earthworms were identified and recorded from the three sampling locations. Eudrilus eugeniae (54.9%) was the most abundant species followed by Hyperidrilus africanus (20.3%), Libyodrilus violaceous (19.6%) and Alma millsoni (6.3%) with the least abundant species. The result of the diversity indices showed Science village (1.13) as the most diverse habitat followed by Emelda hostel (0.86) and Boys’ hostel (0.84) with the least diversity of species. Soil pH ranged from 2.25 to 4.06 and total organic matter ranged from 14.10 to 16.36%. Soil temperature was uniform with an average value of 27°C for the three sampling locations. The soil moisture content ranged from 11.19 to 14.12%. The conductivity recorded the lowest value (25.60μS/cm) in Emelda Hostel and highest value (111.8 μS/cm) in Science village. The study provided understanding into the patterns of earthworm populations in Nnamdi Azikiwe University, Awka and the need for the conservation of earthworm diversity. Better understanding about habitat and living conditions of earthworms is required to provide suitable and enhanced production of vermicompost in different geographic conditions.

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Oxidative Stress Induced DNA Damage and Reproductive Toxicity in Male Albino Mice Orally Exposed to Sorbitol

Abstract

In this study, the potential DNA damage and reproductive toxicity of sorbitol was investigated using bone marrow micronucleus (MN), sperm morphology, and sperm count in mice. Five doses of 90, 45, 20, 10 and 1 mg/kg/day, defined by allometry, and approximately corresponding to 1.5g, 750mg, 330mg, 165mg and 16mg of sorbitol daily consumption by a 70kg human, respectively, were used. MN analysis showed a dose-dependent induction of micronucleated polychromatic erythrocytes and other nuclear abnormalities across the treatment groups. Assessment of sperm shape showed a significant (p < 0.05) increase in sperm abnormalities with significant (p < 0.05) decrease in mean sperm count in treated groups. The result of the oxidative stress biomarkers showed induction of significant (p < 0.05) increase in liver catalase, MDA and serum ALT and AST activities with concomitant decrease in SOD activities in exposed mice. A significant increase in weight of exposed mice were recorded when compared with the negative control. The results of this study showed the genotoxicity and reproductive effects of sorbitol.

Open access
Screening for Bio-flocculant Producing Bacterial Strains from Asa River in Ilorin Kwara State

Abstract

Synthetic flocculants in water treatment have been reported to be detrimental to both human health and the environment. Thus, there is a constant search for bio-flocculants that is safe and addresses the effects of synthetic polymers. This study was aimed at isolating bacteria with bio-flocculating potential, their molecular identification and phylogenetic relatedness, and the optimization of their flocculating abilities from an open water (Asa River) in Ilorin Kwara State. The effect of carbon source (glucose, lactose and starch), cations (FeSO4, KCl and CaCl2) and pH (2 to 12) was evaluated on the bio-flocculating activities of the isolates using kaolin clay. The seven (7) novel (new strains) isolates with their respective accession number from National Center for Biotechnology Information (NCBI) after molecular confirmation are Pseudomonas otitidis MTK01 (MK263227), Aeromonas caviea MTK02 (MK263228), Providencia alcalifaciens MTK03 (MK263229), Providencia sp. MTK05 (MK263230), Alcaligenes sp. MTK06 (MK263231), Klebsiella pneumoniae MTK07 (MK263232) and Klebsiella sp. MTK08 (MK263233) while Raoultella ornithinolytica MTK04 was also identified. Phylogenetic tree of relatedness showed close kin of the isolates to established bacteria sequence deposited at the NCBI GenBank. Although the flocculating rate of each isolates varied with different parameters that was used in the study, glucose was the most supportive followed by lactose and starch, CaCl2 was most supportive cation followed by KCl and FeSO4 while pH 12, 6, 8, 10, 2 and 4 were the order of decreasing flocculating rate of the medium. This study has reported the presence of eight (8) bio-flocculating bacteria (out of which 7 are new strains of bacteria) in an open water which has been further optimized for effective flocculating rate and thus provides an ecofriendly and harmless flocculants source that can be employed in water treatment procedures.

Open access
Green Nanotechnology in Nigeria: The Research Landscape, Challenges and Prospects

Abstract

In this treatise, we examined the activities of researchers of Nigeria descent in the frontier areas of nanoscience and nanotechnology, with a focus on green nanotechnology. The exploration of literature published by scholars were reviewed and compartmentalized on the basis of applications of the nanomaterials. It can be concluded that the level of activities in this area is expanding owing to the emergence of more published works since the beginning of 2010. However, in comparison with research outputs from other developing African countries such as South Africa and Egypt, activities in green nanotechnology are still at low ebb in Nigeria. Issues that are contributory to the slow pace were identified and appropriate solutions in terms of improved funding of education, enactment of national policy on nanotechnology, curriculum development, international cooperation as well as human resource development among others were discussed.

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A Needs Assessment For Indigenous African Language-Based Programming Languages

Abstract

The development of an African native language-based programming language, using Yoruba as a case study, is envisioned. Programming languages based on the lexicons of indigenous African languages are rare to come by unlike those based on Asian and / or European languages. Availability of programming languages based on lexicons of African indigenous language would facilitate comprehension of problem-solving processes using computer by indigenous learners and teachers as confirmed by research results. In order to further assess the relevance, usefulness and needfulness of such a programming language, a preliminary needs assessment survey was carried out. The needs assessment was carried out through design of a structured questionnaire which was administered to 130 stakeholders in computer profession and computer education; including some staffers and learners of some primary, secondary and tertiary educational institutions in Oyo and Osun states of Nigeria, Africa. The responses to the questionnaire were analyzed using descriptive statistics. The analysis of the responses to the questionnaire shows that 89% of the respondents to the questionnaire expressed excitement and willingness to program or learn programming in their mother tongue-based programming language, if such a programming language is developed. This result shows the high degree of relevance, usefulness and needfulness of a native language-based programming language as well as the worthwhileness of embarking on development of such a programming language.

Open access
Antisickling Effects of Quercetin may be Associated with Modulation of Deoxyhaemoglobin, 2, 3-bisphosphoglycerate mutase, Redox Homeostasis and Alteration of Functional Chemistry in Human Sickle Erythrocytes.

Abstract

It is now glaring that sickle cell anaemia is still one of the highest leading inbred hemoglobinopathy amongst Africans. This study examined the antisickling effects of quercetin via modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocyte using in silico and in vitro models while espousing preventive and curative approaches. Quercetin was docked against deoxy-haemoglobin and 2, 3-bisphosphoglycerate mutase, with binding energies (−30.427 and −21.106 kcal/mol) and Ki of 0.988μM and 0.992μM at their catalytic sites via strong hydrophobic and hydrogen bond interactions. Induction of sickling was done using 2% metabisulphite at 3h. Treatment with quercetin prevented sickling outstandingly at 5.0μg/mL and reversed same at 7.5μg/mL, 83.6% and 75.9%, respectively. Quercetin also significantly (P<0.05) maintained the integrity of erythrocyte membrane apparently from the observed % haemolysis relative to untreated. Quercetin significantly (P<0.05) prevented and counteracted lipid peroxidation while stimulating GSH and CAT levels which were detected to considerably (P<0.05) increase with simultaneous significant (P<0.05) reduction in SOD level based on curative approach. Umpiring from our FTIR results, a favorable alteration in the part of functional chemistry in terms of shifts (bend and stretches) and functional groups were observed relative to the induced erythrocyte/untreated. Thus, antisickling effects of quercetin may be associated with modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocytes.

Open access
Application of solid-phase extraction for isolation of coumarins from wine samples

Abstract

Coumarins can be as a result wine storage and aging in wood drums and they can affect organoleptic characteristics of wine. The aim of this work was to determine the content of coumarins in wine samples originated from Slovak Tokaj wine region. The HPLC method with high specificity, accuracy, precision, and recovery was proposed. SPE sorbents of C18 type, styrene-divinylbenzene copolymer and molecularly imprinted polymers were compared for extraction of six coumarins, coumarin, aesculin, scoparone, scopoletin, 4-methylumbelliferone, and herniarin. Higher recoveries (above 89 %; except aesculin – recoveries higher from 68 %, RSDs less than 6 %) were obtained with selective polymeric sorbent laboratory prepared by molecularly imprinted technology. The results showed that content of coumarins in wine samples are in ng.mL−1 concentration levels and depend on the age and wine puttony.

Open access
Biologically valuable components, antioxidant activity and proteinase inhibition activity of leaf and callus extracts of Salvia sp.

Abstract

Sage is medicinal plant, known for its antioxidant and anti-inflammatory effects. Eight extract samples were tested in this study: extract from Salvia officinalis L. varieties from two different geographical localities (Jaslovské Bohunice and Pobedim, Slovakia), Salvia officinalis L., variety “bicolor”, Salvia officinalis L., variety “purpurescens”, Salvia apiana, Salvia divinorum, and two callus cultures of Salvia sclarea L. and Salvia aethiopis L. The highest values for composite parameters were observed for extract from Salvia apiana. It can be concluded that prepared sage extract samples are rich on polyphenolic acids (2 950±265 μg.mL−1 GAeq.) and amines (197±5.50 μg.mL−1 TRPeq.). HPLC analysis confirmed the dominant content of rosmarinic acid in the extracts; the highest content was detected in the Salvia apiana extract (1 120±15 μg.mL−1). Extract from Salvia apiana expressed too the highest antioxidant activity (1 710 – 4 669 μg.mL−1TEAC). Similarly, the highest inhibition activity was observed for this extract on thrombin (57±3.3 %) and on other proteinases (over 80 %). Spearman correlation analysis and PCA analyses revealed a coherence between antioxidant activity of samples and their content of rosmarinic acid as well as inhibitory activity towards particular proteases, and revealed the significance of thiol based secondary metabolites. Cluster analysis demonstrates the differences of Salvia apiana extract from extracts of S. officinalis L., the group of S. divinorum extract and from callus cultures.

Open access
Characterization of a novel lipase from Pseudomonas aeruginosa

Abstract

Lipases cleaving oils into fatty acids and glycerol are of great interest for the use in increasing the efficiency of fuels. In this work, a novel lipase from Pseudomonas aeruginosa, P. aeruginosa A12, was isolated by ion-exchange and hydrophobic chromatography. The purity of lipase was shown by electrophoresis and its molecular weight was estimated to be ~ 31.6 kDa. The whole amino acid sequence was analyzed by an LC-MS/MS method. Temperature- and pH-dependent optimum of the enzyme compiled 30 °C and 7.5, respectively. The obtained enzyme exhibited 79 % similarity of amino acid sequence to a lipase isolated from the same strain of P. aeruginosa. Thus, the novel lipase was determined to belong to I.1 subfamily of bacterial true lipases. Three dimensional structure of the isolated lipase isoform was modeled based on obtained sequences. Amino acids forming the catalytic domain were shown in the model. Lid domain is suggested to be in the open conformation. These results provide a potential alternative for enzymatic digestion of fuel oils and serve for the development of fundamental knowledge of lipase activity.

Open access
A Coupled Insulin and Meal Effect Neuro-Fuzzy Model for The Prediction of Blood Glucose Level in Type 1 Diabetes Mellitus Patients.

Abstract

Diabetes Mellitus is a metabolic disorder that affects the ability of the human body to properly utilize and regulate glucose. It is pervasive world-wide yet tenuous and costly to manage. Diabetes Mellitus is also difficult to model because it is nonlinear, dynamic and laden with mostly patient specific uncertainties. A neuro-fuzzy model for the prediction of blood glucose level in Type 1 diabetic patients using coupled insulin and meal effects is developed. This study establishes that the necessary and sufficient conditions to predict blood glucose level in a Type 1 diabetes mellitus patient are: knowledge of the patient’s insulin effects and meal effects under diverse metabolic scenarios and the transparent coupling of the insulin and meal effects. The neuro-fuzzy models were trained with data collected from a single Type 1 diabetic patient covering a period of two months. Clarke’s Error Grid Analysis (CEGA) of the model shows that 87.5% of the predictions fall into region A, while the remaining 12.5% of the predictions fall into region B within a four (4) hour prediction window. The model reveals significant variation in insulin and glucose responses as the Body Mass Index (BMI) of the patient changes.

Open access