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Disease caused by Tomato yellow leaf curl virus (TYLCV) brings serious production losses of cultivated tomato worldwide. In our previous study, two novel amino acid derivatives exerted satisfactory antiviral activities against TYLCV. In this study, the variation of TYLCV, the transcriptional expression level of Ty- 1 and the enzyme activities of POD and PPO in tomato were monitored after treatment with two amino acid derivatives to illustrate the antiviral mechanism. The results showed the symptom severity caused by TYLCV was reduced significantly by two compounds and was associated with the inhibition of viral DNA level at the early stage. Among three levels of concentration, the highest inhibition rate of CNBF-His was 40.66 % at 1000 mg/L, for CNBF-Asn, the highest inhibition rate was 36.26 % at 2000 mg/L 30 days post-inoculation. Two compounds could also enhance the activities of PPO and POD and the transcriptional expression level of Ty- 1 which correlates with plant resistance in tomato. In the field test, two compounds increased the yields of tomato and the maximum increase of yield was 37.66 %. This is the first report of novel amino acid derivatives inducing resistance in tomato plant against TYLCV. It is suggested that amino acid derivatives have the potential to be an effective approach against TYLCV in tomato plant. [ABSTRACT FROM AUTHOR]

The excessive application of pesticides increases the pollution potential, which leads to groundwater contamination and spreading of toxic substances in the environment by leaching or in runoff. In this study, new herbicide ionic liquids (HILs) based on fomesafen with multifunctions were prepared to improve the herbicidal activity and reduce the risk to the aquatic organisms. The octanol–water partition coefficient (Kow), surface activity, soil adsorption and herbicidal activity of HILs were tested and a comparative analysis with fomesafen was made. The results show that HILs have low water solubility, excellent Kow, low surface tension, and good adsorption ability, and these properties can be regulated and optimized by selecting different counter cations. The physico-chemical properties of HILs were related to the carbon chain length of the cation. Compared with fomesafen sodium, ionic liquids N-1 showed a higher and faster herbicidal activity because of its good lipophilicity and low surface tension. HILs with lower water solubility and greater adsorption capacity in soil have less risk to algae, snail and other aquatic organisms than fomesafen sodium. The HILs will be a candidate in fomesafen applications in the future. [ABSTRACT FROM AUTHOR]

Controlled release formulation of pesticides is highly desirable for attaining the most effective utilization of the pesticide as well as reducing environmental pollution. Nano-sized controlled release formulations can provide better penetration through cuticle and deliver the active ingredients efficiently to the targeted tissue. In this study, a novel strategy for the preparation of a nanoconjugate derived from kasugamycin with amino-modified silica was developed. The kasugamycin was connected with amino-modified silica matrix by an amide bond, which could avoid the initial burst release effectively and prolong the duration remarkably. The results showed the kasuga-silica can protect kasugamycin against photo-degradation effectively and the release rate of the active ingredient of nanoconjugate was related to the temperature, pH value, and the particle size (52.5-315.4 nm). With reduced particle size as well as increased temperature and acidity, the release of the active ingredient was faster. This amide linkage of kasuga-silica could be degraded by amidase effectively. This nanoconjugate displayed a better and a sustained bactericidal efficacy against E. coli than kasugamycin technical, which makes it a potential candidate as a controlled release conjugate for kasugamycin in the future. [ABSTRACT FROM AUTHOR]

The use of bilberry ( Vaccinium myrtillus L.) as a food and medicine for improving human vision has a long history all over the world. However, there is lack of convincing evidence from rigorous clinical trials or scientific research. This study investigated the effects of different concentrations of bilberry extracts on the cell viability, cell cycle and the expression of hyaluronic acid and glycosaminoglycans of cultured human corneal limbal epithelial cells. The data showed that bilberry extracts had no cytotoxicity to the corneal limbal epithelial cells at a wide range of concentrations (10−9-10−4 M, equalized to the content of cyanidin-3-O-glucoside). Bilberry extract (10−6, 10−5 and 10−4 M) increased cell viability after 48 h incubation. The number of cells decreased in G0/G1 phase and increased prominently in S and G2/M phases after treatment with bilberry extracts at a high concentration (10−4 M). The expression of glycosaminoglycans increased prominently after incubation with bilberry extracts (10−7 and 10−4 M) for 48 h while no significant changes were observed for the expression of hyaluronic acid. The results indicated that bilberry extract may be beneficial for the physiological renewal and homeostasis of corneal epithelial cells. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]