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BACKGROUND 6-Benzylaminopurine (6-BA) has a close relationship with the stress resistance of plants. Little research has been carried out on the effects of 6-BA on the cold resistance of postharvest fruits and vegetables. Therefore the aim of the present study was to evaluate the effects of 6-BA on chilling injury (CI), antioxidant system and energy status in cucumber during storage. RESULTS The results showed that 6-BA at 50 mmol L−1 was most effective to restrain CI in cucumber fruit. Fruits treated with 50 mmol L−1 6-BA maintained higher levels of chlorophyll, ascorbic acid, total phenolics and total antioxidant capacity. Furthermore, this treatment reduced the increases in membrane permeability and lipid peroxidation, delayed the increases in both rate of production and H2O2 content and increased the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) under chilling stress. The treatment also increased the content of adenosine triphosphate (ATP) and resulted in a higher level of energy charge. CONCLUSION These results indicated that 6-BA alleviated CI in cucumber fruit through improving antioxidant enzyme activities and total antioxidant capacity and maintaining higher levels of ATP content and energy charge.© 2012 Society of Chemical Industry

A novel effective starch-based adsorbent was prepared through two common reactions, which included the esterification of starch with excess maleic anhydride in the presence of pyridine and the cross-linking reaction of the obtained macromonomer with acrylic acid by using potassium persulphate as initiator. The percentage of carboxylic groups of the macromonomer ranged from 14% to 33.4%. The cross-linking degree of the adsorbent was tailored with the amount of acrylic acid which varied from 10 wt% to 80 wt%. Both Fourier transform infrared spectra and thermogravimetric analysis results verified the structure of the adsorbent. The maximum gel fraction and swelling ratio of the adsorbent were about 72% and 6.25, respectively, and they were able to be adjusted with the amount of monomers. The weight loss percentage of the adsorbent could reach 96.9% after immersing in the buffer solution that contained α-amylase for 14 h. It was found that the adsorption capacities of the adsorbent for lead and mercury ions could be 123.2 and 131.2 mg/g, respectively. In addition, the adsorbent was able to remove ca . 51–90% Pb(II) and Hg(II) ions that existed in the decoctions of four medicinal herbals.

The bis(benzimidazol-1-yl)methane molecule of the title compound, C15H12N4·2H2O, displays a trans conformation with a twofold axis running through the methylene C atom. Two adjacent water molecules are bonded to this molecule through O—H...N hydrogen bonds, forming a trimer. Adjacent trimers are connected together via C—H...O interactions, forming a chain running along the b-axis direction. Two such chains are joined together via π–π interactions [centroid–centroid distance = 3.556 (2) Å], forming double chains, which are connected via the water molecules through C—H...O associations, forming a sheet structure. The sheets are stacked on top of each other along the a-axis direction and connected through O—H...O and C—H...O interactions, forming a three-dimensional ABAB layer network structure.