Anthocyanins, synthesized via the flavonoid pathway, are a class of crucial phenolic compounds which are fundamentally responsible for the red color of grapes and wines. As the most important natural colorants in grapes and their products, anthocyanins are also widely studied for their numerous beneficial effects on human health. In recent years, the biosynthetic pathway of anthocyanins in grapes has been thoroughly investigated. Their intracellular transportation and accumulation have also been further clarified. Additionally, the genetic mechanism regulating their biosynthesis and the phytohormone influences on them are better understood. Furthermore, due to their importance in the quality of wine grapes, the effects of the environmental factors and viticulture practices on anthocyanin accumulation are being investigated increasingly. The present paper summarizes both the basic information and the most recent advances in the study of the anthocyanin biosynthesis in red grapes, emphasizing their gene structure, the transcriptional factors and the diverse exterior regulation factors.

The PufX membrane protein is essential for photosynthetic growth of Rhodobacter sphaeroides wild-type cells. PufX is associated with the reaction center-light harvesting 1 (RC-LH1) core complex and plays a key role in lateral ubiquinone/ubiquinol transfer. We have determined the PufX/RC stoichiometry by quantitative Western blot analysis and RC photobleaching. Independent of copy number effects and growth conditions, one PufX molecule per RC was observed in native membranes as well as in detergent-solubilized RC-LH1 complexes which had been purified over sucrose gradients. Surprisingly, two gradient bands with significantly different sedimentation coefficients were found to have a similar subunit composition, as judged by absorption spectroscopy and protein gel electrophoresis. Gel filtration chromatography and electron microscopy revealed that these membrane complexes represent a monomeric and a dimeric form of the RC-LH1 complex. Since PufX is strictly required for the isolation of dimeric core complexes, we suggest that PufX has a central structural role in forming dimeric RC-LH1 complexes, thus allowing efficient ubiquinone/ubiquinol exchange through the LH1 ring surrounding the RC.

A new nitrile-tethered pyridinium polyoxometalate (POM) was prepared by anion-exchange of the ionic liquid precursor [N-butyronitrile pyridine]Cl ([C 3 CNpy]Cl) with the Keggin phosphovanadomolybdic acid H 5 PMo 10 V 2 O 40 (PMoV 2 ), and the obtained organic POM salt [C 3 CNpy] 4 HPMoV 2 was characterized by XRD, SEM, TG, 1 H NMR, 13 C NMR, ESI-MS, CHN elemental analysis, nitrogen sorption experiment, and melting point measure. When used as a catalyst, [C 3 CNpy] 4 HPMoV 2 causes the first example of reactioncontrolled phase-transfer hydroxylation of benzene with H 2 O 2 , showing high activity and stable reusability. Based on spectral characterizations and comparisons of reaction results, plus the reversible color change between fresh and recovered catalyst, a unique reaction mechanism is proposed for understanding the highly efficient [C 3 CNpy] 4 HPMoV 2 -catalyzed phase-transfer catalysis. The formation of dissolvable active species [VO(O 2 )] + is responsible for the phase-transfer behavior, while the intramolecular charge transfer and the protonated nitrile in cations accelerate the reaction and favor a better catalyst recovery rate.

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