RESUMO
Environmental contaminations by heavy metals are currently an increasing public health concern globally. One key challenge of these toxic metals is the extremely difficulties involved in their detoxification from the environment and effluents because of their non-degradability. An efficient biologic agent with potentials of remediating these toxic metals may ease these ever-increasing problems. We reported toxic metals tolerance and bioremediation potentials of novel bacteria sp. Strains USL2S, USL4W and USL5W isolated from Uburu salt lake, Ebonyi State, Nigeria. The phenotypic characteristics and the 16S rRNA gene analyses revealed that USL2S strain belongs to the genus Klebsiella, whereas USL4W and USL5W strains belong to the genus Pseudomonas. The bacteria isolates grew well in media containing 5-15 % of sodium chloride. The bacteria isolate showed capacity to tolerate 50.0 mM Hg+2 and Pb+2, 17.0, 12.50 and 4.0mM Ni+2, Cd+2, and Zn+2 respectively in solid media. Pseudomonas putida A4W Strain also tolerated 16.0 mM Cu+2, while Klebsiella sp. Strain USL2S, Pseudomonas putida USL5W Strain tolerated 4.0 mM each. AAS analyses showed 85, 95, and 95 % Hg; 97.13, 98.89, and 97.55 % Pb; 73.33, 77.42 and 69.72 Cd; 88.06, 99.54, and 97.91 % Ni; 100, 100 and 83.62% Cu; 42.30, 84.52 and 98.80 % Zn removal from media broth incorporated with the tested metals by Klebsiella sp. USL2S, Pseudomonas sp. Strain USL5W and Pseudomonas sp. USL4W respectively. We therefore recommend these novel moderately halophilic and metal tolerant isolates as possible biologic agents for effective bioremediation of mercury, lead, cadmium, nickel, copper and zinc in contaminated environments and effluents.
RESUMO
BACKGROUND: Traditional medicine intervention has been used in rheumatoid arthritis (RA) treatment due to limitations of conventional drugs. OBJECTIVE: This study aimed at evaluating the anti-arthritic potentials of ethanol and aqueous extracts of stem bark of Cleistopholis patens (SBCP) in complete Freund's adjuvant (CFA) induced rheumatoid arthritis in rats. MATERIALS AND METHODS: Rheumatoid arthritis was induced in groups 2 to 9 by intradermal injection of 0.1 mlkg-1 chicken type II collagen in CFA into the left hind paw of the rats. Group 1 served as normal control. Group 2 (negative control) received 5 mlkg-1 body weight normal saline while group 3 (positive control) received 10 mg/kg body weight standard drug (indomethacin). Groups 4 to 9 received varied doses of the extracts. After 10 days of RA induction, rats were treated with ethanol and aqueous extracts of SBCP orally at a dose of 400, 600 and 800 mgkg-1 for 21 days. The paw size, body weight changes, inflammatory parameters, lipid peroxidation maker and malondialdehyde (MDA) were assessed. RESULTS: Rheumatoid arthritis induction caused marked (p < 0.05) increase in paw size, inflammatory makers and MDA while significant (p < 0.05) reduction was observed in body weight relative to normal control. Treatment with extracts analogous to indomethacin markedly (p < 0.05) decreased the paw size and caused weight gain while the altered inflammatory parameters and MDA were reversed relative to negative control. CONCLUSION: The findings suggest that the extracts of SBCP have good antiarthritic potentials comparable to indomethacin and hence could be used in rheumatoid arthritis management.
RESUMO
Psychotria microphylla is a plant found in Africa and many parts of the world where the leaves are locally used in folk medicine for the treatment of toxicity related liver diseases. We investigated the antioxidant potentials of ethanol leaf extract of Psychotria microphylla (ELE-PM) in restoring hepatic redox dysregulations in rats exposed to heavy metals. HPLC was used in quantifying the bioactive compounds in ELE-PM. DPPH (1,1-diphenyl-2 picrylhydrazyl), FRAP (Ferric reducing antioxidant power) and NO (Nitric Oxide) assays were used for in vitro studies. The in vivo studies involved 30 rats randomly divided into 5 groups (n = 6). Group 1 received normal saline (2 mg/kg), group 2, 3, 4 and 5 received a combined solution of Pb(NO3)2 (11.25 mg/kg) and HgCl2 (0.4 mg/kg) respectively. After 7 days of heavy metal exposure, groups 3, 4 and 5 received a daily bolus administration of 200, 400 and 600 mg/kg body weight of EE-PM respectively through oral intubation for 28 days. HPLC quantification revealed a high amount of quercetin (27.43 ± 0.04 mg/100g), lower amounts of gallic acid (7.60 ± 0.06 mg/100g) and rutin (0.38 ± 0.009 mg/100g). Additionally, ELE-PM demonstrated strong inhibitory potentials against free radical scavenging activity generated in vitro. More interestingly, administration of ELE-PM significantly ameliorated hepatic redox dysregulations elicited by the exposure of the rats to heavy metals in a dose dependent pattern. ELE-PM is highly rich in flavonoid compound quercetin and perhaps this may be responsible for the strong antioxidant potentials exhibited in this investigation.
RESUMO
This study evaluated the level of metals in edible plants, their chemical forms in the soil, and the associated health risk in Enyigba lead-zinc mining vicinity in Ebonyi State, Nigeria. Soil sample, Telfairia occidentalis and Amaranthus hybridus were collected from mining sites (Ishiagu-Enyigba and Elinwobvu-Enyigba) and non-mining site (Ekawoke-control) and analyzed using standard protocols. The results showed that a high percentage of Cd, Pb, Fe, and Zn were associated with non-residual fraction, while Cu, Cr, and Ni were bounded with residual fraction. The order of mobility and bioavailability of the metals was as follows: Pb > Cd > Fe > Zn > Cr > Ni > Cu. Geoaccumulation index (Igeo) indicated moderate to strong pollution of the mining sites with Cd Cu, Pb, and Zn. The most significant contributor to hazard index (HI) was ingestion of edible plants; followed by ingestion, dermal-contact, and then inhalation of soil particles. HI values for Cd (1.32), Cr (1.05), and Pb (1.97-2.04) for children in the sites exceeded United States Environmental Protection Agency (USEPA) safe limit (HI > 1). Total cancer risk (TCR) for adults and children via soil inhalation or soil ingestion were below USEPA safe limit (TCR < 1.0 × 10-4). TCR for adults and children via consumption of T. occidentalis or A. hybridus exceeded USEPA safe limit (TCR > 1.0 × 10-4). These results strongly indicated associated noncarcinogenic and carcinogenic health risk of these metals from the soil and the edible plants around Enyigba mining sites vicinity to humans especially children, this calls for concern.
