No abstract

The aim of this study was to evaluate the toxic effects associated with the administration of aqueous extracts (AE) of Calliandra portoricensis (CP), Dracaena arborea (DA), Duranta repens (DR), Polytrichum juniperinum (PJ), Parmelia caperata (PC), and Nostartium officinale (NO) on Wistar rats. LD 50 for each plant was obtained prior to administration. Seven groups of six rats each were orally gavaged for 28 days as follows; group 1-7 received normal rat pellets and saline, in addition, group 2 received 20 mg/kg b.w CP, group 3 & 4 respectively received 8 mg/kg b.w DA and DR, group 5 & 6 respectively received 4 mg/ kg b.w PJ and PC, and group 7 received 100 mg/kg b.w NO. Liver enzymes; ALP, ALT, AST and GGT were significantly (p < 0.05) elevated by CP, DR, PJ and PC extracts. All the extracts caused significant alterations of the total protein, albumin and globulin levels. The urea levels were deranged by all the extracts while CP, PJ, PC, and NO extracts caused no significant effects on the creatinine levels. Both DR and NO deranged the serum electrolytes; Na, K, Cl, and HCO 3. Results for the lipid profile showed that all extracts significantly altered the phosphatidate phosphohydrolase and LDL levels while no significant effects were observed in the VLDL, TG, TC, HDL, cardiac risk ratio, arterogenic coefficients, and arterogenic index of plasma, of NO treated rats. For hematological parameters DR, PJ, and PC significantly deranged the RBC, HGB, MCHC, MCV, and MCH concentrations while the neutrophils, eosinophils and basophils were significantly altered on administration of all the extracts. No significant effects were observed on the platelets and plateletcrit level in rats gavaged with CP, whereas the MPV, PDW, and PCT concentrations were deranged by DR extracts. CP and NO caused no alterations in the MDA, GSH, and GST levels whereas the SOD, GPx, and xanthine oxidase levels were significantly deranged by all the plant extracts. Only NO treatment produced catalase, glutathione reductase, and xanthine dehydrogenase levels equivalent to the control group. This study has shown various degrees of deleterious effects on biochemical parameters associated with the consumption of these plants, thus raising serious concerns over their continuous applications as local medicaments.

No abstract

Lipases are hydrolytic enzymes responsible for the hydrolysis of triacylglycerol into glycerol and free fatty acids. The biodiversity of crude oil contaminated soil was explored for the isolation of novel potent lipase producing microorganisms. In this current study, microorganisms isolated from crude oil contaminated soils were screened for lipase activity and expression. Six fungal strains namely: Yeast, Aspergillus flavus, Aspergillus niger, Verticillus sp., Penicillum sp., and Microsporum audouini demonstrated lipase producing potentials and the best two: Verticillus sp. and Penicillum sp. were selected for enzyme production and characterization. The lipase enzyme was produced in broth medium. Optimization of selected biochemical parameters reveal that optimum temperature for lipase activity was 40 ºC, pH 7 with an incubation time of 168 h for lipase expressed by Verticillus sp. and 40 ºC, pH 8 with an incubation time of 144 h was established for lipase expressed by Penicillium sp. The kinetic parameters of the lipase enzyme revealed that the enzymes had low Km (0.19 and 0.30 respectively) for the selected substrate.

For the last century, crude oil exploitation and exploration have occurred in the Niger Delta of Nigeria. While oil and gas account for a significant 85% of the national GDP, it has caused catastrophic effects on the environment. This is of particular concern, considering the Niger Delta is the breadbasket of Nigeria, inhabited by 31 million people. However, indiscriminate pollution has arisen from oil spills emanating from exploration activities and gas flaring. Since 2014 alone, more than 550 oil spills have been reported. To address this, the Nigerian federal government has developed environmental policies and laws targeted to regulate environmental management. However, the efficacy of these policies remains in question because of the government's unwillingness to enforce the laws. The aim of this paper is to appraise of the effect of the national policies on environmental management with emphasis on the "Guidelines and Standards for Environmental Pollution Control, 1991". We ask the following questions: What are community perceptions of the direct and indirect impacts of oil spills on ecosystems, health, livelihoods, migration and conflict? What are current and desired compensation provided by government bodies, NGOs and oil companies to support local livelihoods impacted by oil spills? What are key statutory and legal frameworks on environmental protection in Nigeria, how effectively are they performing and what are key challenges confronting compliance with regulatory guidelines and standards? To answer these questions, we recruited the activities of 11 focus groups comprising of chiefs, farmers, youth leaders, members of community and social activists groups from each Niger Delta state and engaged them on qualitative focus group discussions and interviews to identify the impacts of oil spills on settlement's socio-economic and environmental conditions. Results were then analyzed with thematic templet analytic techniques. This study reveals a high impact on settlements with diverse factors that have contributed to the increase in social aspects. Existing policies to regulate and control environmental pollution, but the enforcement of standards has been poor. Consequently, biodiversity has been impacted, affects agricultural soil, human health and the source of farming and farming livelihoods of the indigenous people has had to be abandoned by many living in this region. We argue, Nigeria's reliance on revenue generated from crude oil encourages the uninspiring and lackadaisical approach of the government to enforce these policies in the region. To this end, we recommend various environmental policies should be merged and harmonized under one by-law to ensure uniformity and there is an urgent need Extended author information available on the last page of the article to implement the 2006 UNDP report which prioritized environmental sustainability, promotes human partnership development and upholds the goals for sustainable development.