Precipitate with proteins

Easy to be oxidized: Give out the H atom to the oxidant

Chelate with metal

Weak acid: pka ~ 9

Absorb light at 280 nm wavelength

Solubility decreases with the length of the chain

High molecular weight

Low molecular weight

examine the response of a whole animal, an isolated tissue / cell line or an organism, to a given extract (or drug, chemical or pollutant) in order to evaluate the bioactivity

Differentiate: molecular models - activity but not physiology; organism models- have physiological and biochemical differences while there are bioethical issues with human; cellular models - limit to HeLa cells

2 main problems: Synergy and antagonism

Usually inspired by folk medicine

Stability

Bioavailability

Biotransformation: Bioactivation and biodegradation

Pharmacokinetics

Developement of a cranberry standard for quantification of insoluable proanthocyanidins. The standard was made through 5 steps including breaking up the particles, get rid of polyphenols, separate off small polyphenols, find concentration by DMAC, and characterize the std with MADLDI - MS. The mass spec reflected the structural heterogeneity of PACS in cranberry fruits and agreed with the previous literature. The standard was then used to quantify soluable and insoluble proanthocyanidins.

Portable NIR can be used in placed of benchtop NIR for the analysis of catechins in green tea using GA-PLS variable selection method.

GC-MS, LC-MS, MS, NMR, etc

Cleaning:Minimize noises

Fingerprint: Quantitative comparisons based on retention time/peak area

PCA is a common used technique: Form clusters based on principle components

phloretin glucuronide and phloretin sulfate are potential biomarker for apple intake as these 2 compounds present in higher intensities with apple consumption compared to control beverage. However, the results show unknown reliability and stability for both, which makes them less than a perfect bio food marker

Research question: What kind of polyphenols/stillbenoids are found in the stems of grapevines ? How much variation occurs in these compound amounts between different grape species.Experiment: They used 8 species of grape controlled for soil type, distance between crops, age, and microenvironment. The grapevine were pruned, left to develop stillbenoids, ground, and then extracted. Qualitative analysis were done by UPLC-MS. Data were analyzed by PCA and PLS-DA. Results: Data analysis showed low variance between same species of grapes. PLS-DA showed a separation of metabolites found in red and white graphes. The clusters and network correlated well with the species correlation