An HPLC-DAD method has been developed to quantitatively analyze for the content of zeaxanthin dipalmitate, a major carotenoid in Fructus Lycii, in different species of the genus Lycium. Determination was performed using an Alltima C18 column with the mobile phase consisting of acetonitrile and dichloromethane (42:58). The total contents of carotenoids in these samples were also determined by using UV spectrophotometric assay. Total carotenoid concentrations of different Fructus Lycii are within the range of 0.03-0.5%. Zeaxanthin dipalmitate is a predominant carotenoid, comprising 31-56% of the total carotenoids in Fructus Lycii. This study is the first systematic quantification of the carotenoids in the fruits of different Lycium species. The results demonstrated that these methods are reliable and facile techniques for rapid analysis of carotenoids for crude drug and plant-derived food supplements.

Isorhapontigenin (ISO) is a new derivative of stilbene compound that was isolated from the Chinese herb Gnetum Cleistostachyum, and has been used for treatment of bladder cancers for centuries. In our current studies, we have explored the potential inhibitory effect and molecular mechanisms underlying ISO anti-cancer effects on anchorage-independent growth of human bladder cancer cell lines. We found that ISO showed a significant inhibitory effect on human bladder cancer cell growth and was accompanied with related cell cycle G0/G1 arrest as well as downregulation of Cyclin D1 expression at the transcriptional level in UMUC3 and RT112 cells. Further studies identified that ISO down-regulated Cyclin D1 gene transcription via inhibition of SP1 transactivation. Moreover, ectopic expression of GFP-Cyclin D1 rendered UMUC3 cells resistant to induction of cell cycle G0/G1 arrest and inhibition of cancer cell anchorage-independent growth by ISO treatment. Together, our studies demonstrate that ISO is an active compound that mediates for Gnetum Cleistostachyum’s induction of cell cycle G0/G1 arrest and inhibition of cancer cell anchorage-independent growth through down-regulating SP1/Cyclin D1 axis in bladder cancer cells. Our studies provide a novel insight into understanding the anti-cancer activity of the Chinese herb Gnetum Cleistostachyum and its isolate ISO.

Optochin, a cinchona alkaloid derivative discovered over 100 years ago, possesses highly selective antibacterial activity toward Streptococcus pneumoniae. Pneumococcal disease remains the leading source of bacterial pneumonia and meningitis worldwide. The structure−activity relationships of optochin were examined through modification to both the quinoline and quinuclidine subunits, which led to the identification of analogue 48 with substantially improved activity. Resistance and molecular modeling studies indicate that 48 likely binds to the c-ring of ATP synthase near the conserved glutamate 52 ion-binding site, while mechanistic studies demonstrated that 48 causes cytoplasmic acidification. Initial pharmacokinetic and drug metabolism analyses of optochin and 48 revealed limitations of these quinine analogues, which were rapidly cleared, resulting in poor in vivo exposure through hydroxylation pendants to the quinuclidine and O-dealkylation of the quinoline. Collectively, the results provide a foundation to advance 48 and highlight ATP synthase as a promising target for antibiotic development.