NEW MOLYBDENUM-HYPERACCUMULATOR AMONG PLANT SPECIES GROWING ON MOLYBDENUM MINE- A BIOCHEMICAL STUDY ON TOLERANCE MECHANISM AGAINST METAL TOXICITY

The aim of this work was to determine metal accumulation by plants growing on three molybdenum-mine zones and their tolerance strategies. The plants from tailing, extracting and non-contaminated zones were sampled with their corresponding soils. The results show that molybdenum (Mo) and copper (Cu) were at toxic levels in soils and their levels varied in 44 collected species from 21 families. Ajuga chamaecistus and Cramb orientalis L. excluded Mo and Cu, respectively. Achilla tenuifollia as Mo-hyperaccumulator with total Mo (1979 mg kg^?1) and then Erodium ciconium with 1308 mg kg^?1 Mo and Conyza Canadensis with 618 mg kg^?1 Cu were moderate metal accumulators. They stored considerable levels of metals in their leaves vacuoles and elevated the levels of phytochelatins, cysteine and glutathione and induced antioxidant enzymes. In conclusion, this study indicated that some collected plants excluded metals. In metal-accumulators, antioxidant enzymes, phytochelatins and sequestration of excess metals were involved in their tolerance mechanism.     

新疆淡水藻类研究——新月藻属初报

首次报道了新疆新月藻属（ＣｌｏｓｔｅｒｉｕｍＮｉｔｚｓｃｈ）７种,其中４种为新疆维吾尔自治区新记录。这些结果是对１９９１年６～７月所采集的２０号标本鉴定后获得的。     

Analysis of factors affecting diagonal tension and compression capacity of corner joints in furniture frames fabricated with dovetail key

This study was conducted to analyze the effect of joint type, and numbers and types of dovetail keys on diagonal tension and compression performance of corner joints in a furniture frame. Joint members were cut from white fir lumber. Butted and mitered joints were constructed with one and two dovetail key(s) with butterfly and H shapes. Joints were glued by polyvinyl acetate (PVAc) and cynoacrylate (CA). Compression capacity of joints was higher than diagonal tension. Mitered joints were stronger than butted ones. Butterfly dovetail keys were superior to H shape keys. Double keys performed better than single key. Experimental joints glued with PVAc were stronger than those glued with CA glue and control specimens. In terms of strength, butterfly dovetailed joints were comparable with doweled joints.     

Ursene type nortriterpene from Debregeasia salicifolia

A new triterpene, 3beta-19alpha-dihydroxy-30-norurs-12-ene (1), has been isolated from the methanolic extract of Debregeasia salicifolia stems. Its structure has been elucidated with the help of one- and two-dimensional NMR and NOE studies. Lupeol, beta-sitosterol, stigmasterol and oleanolic acid are also reported for the first time from this species.     

Accumulation of Reserve Compounds in Common Bean Seeds under Drought Stress

To investigate the seed protein and major mineral nutrient (Fe, Zn, P, and N) contents and their accumulation procedure in the seeds of common bean (Phaseolus vulgaris L.), a biennial experiment was conducted under two contrasting moisture regimes (normal irrigation and water deficit). Seed reserves of eight genotypes (WA4502-1, WA4531-17, Akhtar, D81083, AND1007, KS21486, MCD4011, and COS16) were investigated at four stages of seed filling period (SFP). Split-plot experiments were performed as randomized complete block design with four replications. The results showed significant differences in the evaluated characteristics in both factors, the genotypes and the moisture regimes. Fe content of the seeds was affected the most by drought stress and reduced in all stages, while seed nitrogen and protein contents were affected the least under stress condition. The percentages of reductions due to water deficit were higher in stage 1 for Fe, stage 2 for Zn, and stage 4 for P and N. In the stage 3, minerals had the least changes. Nitrogen content of the seeds at mid-stages of SFP increased slightly under drought stress. Drought stress also caused 39–69% reductions in the grain yield of the genotypes. Under drought stress condition, the concentrations of Fe and N in the white bean seeds were less than that of the red and the Chitti genotypes. However, the seed P contents of the white bean seeds were higher than that of the other genotypes.     

Water-repellent efficiency of thermally modified wood as affected by its permeability

This study shows how the air permeability of thermally modified wood contributes to its water-repellent efficiency. For this purpose, freshly cut boards of hornbeam(Carpinus betulus), poplar(Populus nigra), and heartwood of oak(Quercus castanifolia) were modified at a steam temperature of 180 °C for 3 h inside a Thermo Wood kiln.The porous structure, permeability, and water uptake of wood were affected differently by thermal modification,depending on the wood species. The creation of microcracks in the cell walls, due to collapsing of fiber cells,resulted in a noticeable increase in the permeability of hornbeam. Despite checking in the poplar wood structure,its permeability was negatively affected by thermal modification. In contrast to oak and poplar, a negative waterrepellent efficiency was observed for the modified hornbeam, caused by an increase in the permeability.     

Acylated flavonol glycosides from Epimedium elatum, a plant endemic to the Western Himalayas

Herba Epimedii is a well-known Botanical preparation used over long time in traditional Chinese medicine. The extracts and chemical constituents from Epimedium species are aphrodisiac as well as to treat many ailments. Chemical investigation of lonely species growing in Kashmir Himalaya Epimedium elatum was undertaken to evaluate its chemical profile. Two unusual substituted acylated flavonol glycosides named Elatoside A (1) and Elatoside B (2) have been isolated from the ethanolic extract of E. elatum along with 23 previously known ones (3-25). All isolates were evaluated for antimicrobial and PPAR-γ ligand binding activity, and some of them appeared to be modestly active.