title: Lead induced responses of Pfaffia glomerata, an economically important Brazilian medicinal plant, under in vitro culture conditions.
abstract: Plantlets of Pfaffia glomerata (Spreng.) were exposed in vitro for 30 days to five lead levels (0-400 μM) to analyze the effects on growth and oxidative stress and responses of various antioxidants vis-à-vis lead accumulation. The plantlets showed significant lead accumulation in roots (1,532 μg g(-1) DW) with a low root to shoot lead translocation (ca. 3.6%). The growth of plantlets was negatively affected by various lead treatments, although the level of photosynthetic pigments did not alter significantly in response to any lead treatment. However, plantlets suffered from oxidative stress as suggested by the significant increase in malondialdehyde levels in root (8.48 μmol g(-1) FW) and shoot (3.20 μmol g(-1) FW) tissues with increasing lead treatments. In response to the imposed toxicity, increases in the activities of catalase in root (4.14 ∆E min(-1) mg(-1) protein) and shoot (3.46 ∆E min(-1) mg(-1) protein) and superoxide dismutase in root (345.32 units mg(-1) protein) and shoot (75.26 units mg(-1) protein), respectively, were observed, while the levels of non-protein thiols and ascorbic acid were not affected significantly in either roots or shoots.
authors.affiliation: Department of Biology, University Federal de Santa Maria, Camobi, Santa Maria, RS 97105-900, Brazil. guptadk1971@gmail.com
authors.forename: D K
authors.initials: DK
authors.lastname: Gupta
authors.forename: F T
authors.initials: FT
authors.lastname: Nicoloso
authors.forename: M R
authors.initials: MR
authors.lastname: Schetinger
authors.forename: L V
authors.initials: LV
authors.lastname: Rossato
authors.forename: H G
authors.initials: HG
authors.lastname: Huang
authors.forename: S
authors.initials: S
authors.lastname: Srivastava
authors.forename: X E
authors.initials: XE
authors.lastname: Yang
mesh_terms: D027703:Amaranthaceae / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D001938:Brazil; D002338:Carotenoids / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D007854:Lead / Q000633:toxicity*; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D010946:Plants, Medicinal / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D011897:Random Allocation; D012989:Soil Pollutants / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D012989:Soil Pollutants; D002734:Chlorophyll; D007854:Lead; D002338:Carotenoids; D008315:Malondialdehyde; D002374:Catalase; D013482:Superoxide Dismutase