NAD-dependent aminoaldehyde dehydrogenase (AMADH, EC 1.2.1.-) from Avena shoots was purified by DEAE Sephacel, hydroxyapatite, 5'-AMP Sepharose 4B, Mono Q, and TSK-GEL column chromatographies to homogeneity by the criterion of native PAGE. SDS-PAGE yielded a single band at a molecular mass of 55 kDa. IEF studies showed a band with a p I value of 5.3. In contrast to AMADHs from other species, the TSK-GEL chromatography showed that AvenaAMADH exists as a monomer in the native state. The purified enzyme catalyzed the oxidations of 3-aminopropionaldehyde (APAL), 4-aminobutyraldehyde (ABAL) N-(3-aminopropyl)-4-aminobutyraldehyde (APBAL), and 4-guanidinobutyraldehyde (GBAL), but not of betaine aldehyde or indoleacetaldehyde. The K(m) values for APAL, ABAL, and GBAL were 1.5x10(-6), 2.2x10(-6), and 1.3x10(-5) M, respectively. Although N-terminal amino acid sequence of Avena AMADH could not be determined due to a modification of the amino residue, the sequence of the fragment of AMADH cleaved by V8 protease showed greater similarity to the barley BADH than to the pea AMADH.

Betaine aldehyde dehydrogenase (BADH; EC 1.2.1.8) is the enzyme that catalyzes the second step in the synthesis of the osmoprotectant, glycine betaine. NADdependent BADH was purified from Avena sativa shoots by DEAE Sephacel, hydroxyapatite, 5 ¢ -AMP Sepharose 4B, Mono Q and TSK-GEL column chromatographies to homogeneity by the criterion of native PAGE, and the properties of BADH were compared with those of aminoaldehyde dehydrogenase purified to homogeneity from A. sativa . The molecular mass estimated by both gel filtration using TSK-GEL column and Sephacryl S-200 was 120 and 115 kDa, respectively. The enzyme is a homodimer with a subunit molecular mass of 61 kDa as shown by SDS-PAGE. The pI value of the enzyme was found to be 6.3. The purified enzyme catalyzed not only the oxidation of betaine aldehyde (BAL), but also that of aminoaldehydes, 3aminopropionaldehyde (APAL), 4-aminobutyraldehyde (ABAL), and 4-guanidinobutyraldehyde (GBAL). The K m values for BAL, APAL, ABAL and GBAL were 5 ¥ 10 -6 , 5.4 ¥ 10 -7 , 2.4 ¥ 10 -5 and 5 ¥ 10 -5 M, respectively. APAL showed substrate inhibition at a concentration of 0.1 mM. A fragment of BADH cleaved by V8 protease shared homology with other plant BADHs.

Green synthetic route of silver nanoparticles (AgNPs) has already been proved to be an advantageous over other physico-chemical approaches due to its simplicity, cost effectiveness, ecofriendly and nontoxicity. In this finding, aqueous Wedelia chinensis leaf extract (WLE) mediated synthesis of AgNPs was approached. Surface plasmon resonance (SPR) band at 408 nm preliminary indicated the formation of AgNPs, while TEM and XRD characterization confirmed the formation of spherically shaped and crystalline AgNPs with an average size of 31.68 nm, respectively. The plausible biomolecules in the aqueous leaf extract responsible for the reduction and stabilization of AgNPs were identified by FTIR analysis and found to be polyphenolic groups in flavonoid. Further, synthesized AgNPs was explored for different biological applications. Biosynthesized AgNPs showed significant free radical scavenging activity as compared to Wedelia leaf extract and antibacterial activity against clinically isolated test pathogens where Gram-negative bacteria were found more susceptible to AgNPs than Gram-positive one. In addition, in vitro cytotoxic response was also evaluated on hepatocellular carcinoma Hep G2 cell lines and showed a dose-dependent cytotoxic response with an IC value of 25 μg/mL.

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Potted young hibiscus (Hibiscus rosa-sinensis ‘Italian Red’) plants were placed in a postharvest environment under low-illumination conditions in a room from 22 July to 31 Dec. 2003. On treatment with a mineral nutrition (MN) solution, 19% of their leaves remained intact after 8 weeks, but all the leaves were lost after 12 weeks from the time of placement. Incorporation of citric acid (CA) into the MN solution at a final concentration of 5 mm considerably suppressed the defoliation so that 57% of the leaves remained intact after 8 weeks and 53% did so after 12 weeks from the time of placement. Furthermore, treatment with 3% sucrose (SUC) instead of CA also considerably suppressed the defoliation, with 26% of the leaves remaining intact for more than 8 weeks and 20% remaining intact for more than 12 weeks. Neither the CA nor the SUC solution was effective in maintaining the hibiscus plants for more than 20 weeks under low illumination. However, treatment with MN solution containing CA and SUC was highly effective in suppressing defoliation. About 60% of the leaves on the plants that were treated with the solution were retained for the entire 24-week period. The proton concentration of the organic solution was found to be a critical factor that affected plant maintenance. The plants survived only on treatment with a solution of pH 5.0, but not with one with a pH of 6.0 or 7.0.