CHEMICAL SCREENING OF PARQUETINA NIGRESCEN LEAF EXTRACT AND EFFECTS ON SELECTED ENZYMES IN LUNGS OF RATS ADMINISTERED WITH DIMETHYPTHALATE

ABSTRACT Parquetina nigrescens is a perennial evergreen woody climber plant with a twinning stem, a ligneous base and a long smooth stem that produces the leaves. Studies have revealed antioxidant, anti-inflammatory, haematological, cytotoxic, antimicrobial, antipyretic, sympathomimetic, uterotonic, hematopoietic, analgesic, and antiulcerogenic properties of the plant. Dimethylphthalate (DMP) is an organic synthetic compound commonly found in plastics, cosmetics, etc and has been reported to induce toxic effects In humans. The present study aims to elucidate the effects of Parquetina nigrescens leaf extract in the lungs of rats treated with Dimethylphthalate (DMP). Parquetina nigrescens leaves were obtained and are authenticated at the Department of pure and Applied biology laboratory LAUTECH Ogbomoso with the voucher number LHO 870, air-dried for three weeks at room temperature and grinded to powdered, followed by soxhlet methanolic extraction to obtain the Parquetina nigrescens leaf extract (PNLE) which was later subjected to rotary evaporation to remove the solvent (methanol) and concentrate the extract. The crude extract is then oven-dried to obtain powdered form of the crude extract. The extract were subjected to Fourier-Transform infrared radiation (FT-IR), High-performance liquid chromatography (HPLC). Twenty- four female white Albino rats (150-250g) were bought from LAUTECH animal House and are divided into six (6) groups( each group with four(4) rats) and are acclimatized for one week. Group A served as the control and group B were give only the DMP(100mg/Kg) which serve as the negative control while the rest from group C to F are treated with a combination of different doses of ASLE(100Mg/Kg, 200Mg/Kg, 300Mg/Kg and 400 Mg/Kg) and DMP(100Mg/Kg) by oral route of administration. The ASLE and DMP are given in corn oil which serves as the vehicle. The ASLE was administered three times per week while the DMP was given twice per week(100mg/Kg) by oral gavage After two weeks the rats were sacrificed by cervical dislocation and lungs were collected and rinse with 1.15% KCl solution and are later centrifuged at 3000RPM for 10minutes to obtain the homogenate. The homogenate was used to determine the GPx, GST activity as well as the total protein in the lung of the rat using spectrophotometer. The heart is also collected and preserved in Formalin-ethanol for RNA analysis. The Fourier-Transform infrared radiation shows 9 prominent peaks at 3369.5cm⁻¹2922.2cm⁻¹, 2851.4cm⁻¹, 1353.0cm⁻¹, 1177.8cm⁻¹, 1069.7cm⁻¹, 1606.6cm⁻¹, 883.4cm⁻¹, 823.7cm⁻¹respectively. The High-performance liquid chromatography (HPLC) shows the presence of twelve (17) different compounds including Caryophellene, 1_8-Cineole, Camphor, Ajmalicin, Alpha linolenic, Magnocurarine, Augmentation, Geranoil, Alpha pinene, Citral, Veraquenain, Beta sitosterol, Kaempferol, Spinosterol, Cymarin, Zeolin and Niral. This study has revealed that Parquetina nigrescen contains diverse functional groups and phytochemicals and that the combination of PNLE and DMP and DMP alone shows no appreciable difference in the total protein concentration in the lungs of rats. However, ACombination of PNLE and DMP slightly reduce (p 0.05) GPx Activity in the lungs of the rats. In addition, Treatment with DMP alone significantly lowered (p