chlorogenic-acid and isochlorogenic-acid

Chlorogenic and isochlorogenic acids are naturally occurring antioxidant dietary polyphenolic compounds found in high concentrations in plants, fruits, vegetables, coffee, and coffee by-products. The objective of this review was to assess the potential health risks associated with the oral consumption of coffee by-products containing chlorogenic and isochlorogenic acids, considering both acute and chronic exposure. An electronic literature search was conducted, revealing that 5-caffeoylquinic acid (5-CQA) and 3,5-dicaffeoylquinic acid (3,5-DCQA) are the major chlorogenic acids found in coffee by-products. Toxicological, pharmacokinetic, and clinical data from animal and human studies were available for the assessment, which indicated no significant evidence of toxic or adverse effects following acute oral exposure. The current state of knowledge suggests that long-term exposure to chlorogenic and isochlorogenic acids by daily consumption does not appear to pose a risk to human health when observed at doses within the normal range of dietary exposure. As a result, the intake of CQAs from coffee by-products can be considered reasonably safe.

Topics: Antioxidants; Chlorogenic Acid; Coffee; Humans; Quinic Acid; Risk Assessment

Caffeoylquinic acid derivatives exhibit anti-inflammatory, antioxidant, and antibacterial activities. We successfully applied pH-zone-refining counter-current chromatography (pH-ZRCCC) to separation of isomeric caffeoylquinic acids from Lonicerae japonicae Flos using a two-phase solvent system composed of ethyl acetate-n-butanol-acetonitrile-water (3:1:1:5, v/v/v/v). Trifluoroacetic acid (10 mM) was added to the upper phase as a retainer and ammonium hydroxide (10 mM) was added to the lower phase as an eluter. As a result, 167.8 mg of chlorogenic acid, 15.9 mg of isochlorogenic acid B, 103.4 mg of isochlorogenic acid C, and 156.0 mg of isochlorogenic acid A were obtained from 1.2 g of crude extract, and all compound purities were over 96%. In addition, by comparing the numeric values of partition coefficient of compounds, it was found that larger differences between the K values of adjacent compounds in the solvent systems resulted in higher sample loading capacities. pH-ZRCCC method is an efficient preparative separation of isomeric caffeoylquinic acids from natural products.

Topics: Acetonitriles; Chemistry Techniques, Analytical; Chlorogenic Acid; Countercurrent Distribution; Hydrogen-Ion Concentration; Lonicera; Plant Extracts; Quinic Acid; Solvents

The study aims to develop a unified method to determine seven phenolic acids (neochlorogenic acid, chlorogenic acid, 4-caffeoylquinic acid, caffeic acid, isochlorogenic acid B, isochlorogenic acid A and isochlorogenic acid C) contained in honeysuckle flower that is the monarch drug of all the eight Yinqiao Jiedu serial preparations using quantitative analysis of multi-components by single-marker (QAMS). Firstly, chlorogenic acid was used as a reference to get the average relative correction factors (RCFs) of the other phenolic acids in ratios to the reference; columns and instruments from different companies were used to validate the durability of the achieved RCFs in different levels of standard solutions; and honeysuckle flower extract was used as the reference substance to fix the positions of chromatographic peaks. Secondly, the contents of seven phenolic acids in eight different Yinqiao Jiedu serial preparations samples were calculated based on the RCFs durability. Finally, the quantitative results were compared between QAMS and the external standard (ES) method. The results have showed that the durability of the achieved RCFs is good (RSD during 0.80% - 2.56%), and there are no differences between the quantitative results of QAMS and ES (the relative average deviation < 0.93%). So it can be successfully used to the quantitative control of honeysuckle flower principally prescribed in Yinqiao Jiedu serial preparations.

Topics: Caffeic Acids; Chlorogenic Acid; Chromatography, High Pressure Liquid; Drugs, Chinese Herbal; Flowers; Hydroxybenzoates; Lonicera; Quinic Acid

The accumulation of amyloid-β (Aβ) is a hallmark of Alzheimer's disease and is known to result in neurotoxicity both in vivo and in vitro. We previously demonstrated that treatment with the water extract of Centella asiatica (CAW) improves learning and memory deficits in Tg2576 mice, an animal model of Aβ accumulation. However the active compounds in CAW remain unknown. Here we used two in vitro models of Aβ toxicity to confirm this neuroprotective effect and identify several active constituents of the CAW extract. CAW reduced Aβ-induced cell death and attenuated Aβ-induced changes in tau expression and phosphorylation in both the MC65 and SH-SY5Y neuroblastoma cell lines. We confirmed and quantified the presence of several mono- and dicaffeoylquinic acids (CQAs) in CAW using chromatographic separation coupled to mass spectrometry and ultraviolet spectroscopy. Multiple dicaffeoylquinic acids showed efficacy in protecting MC65 cells against Aβ-induced cytotoxicity. Isochlorogenic acid A and 1,5-dicaffeoylquinic acid were found to be the most abundant CQAs in CAW, and the most active in protecting MC65 cells from Aβ-induced cell death. Both compounds showed neuroprotective activity in MC65 and SH-SY5Y cells at concentrations comparable to their levels in CAW. Each compound not only mitigated Aβ-induced cell death, but was able to attenuate Aβ-induced alterations in tau expression and phosphorylation in both cell lines, as seen with CAW. These data suggest that CQAs are active neuroprotective components in CAW, and therefore are important markers for future studies on CAW standardization, bioavailability, and dosing.

Topics: Amyloid beta-Peptides; Cell Death; Cell Line, Transformed; Centella; Chlorogenic Acid; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Gene Expression Regulation, Enzymologic; Humans; Neuroblastoma; Neuroprotective Agents; Quinic Acid; tau Proteins