Inhibitory effect of green coffee bean extract on fat accumulation and body weight gain in mice

Nutraceuticals and regulation of adipocyte life: premises or promises

Obesity is the actual worldwide health threat, that is associated with an increased number of metabolic disorders and diseases. Following the traditional hypothesis stating that in obesity hypertrophic adipocytes trigger the adipose tissue hyperplasia, strategies to treat obesity have increased fat researches of the molecular processes that achieve adipocyte enlargement and formation that finally increase body fat mass. Moreover, a new cell type was recently identified, the "brite" adipocyte that presents a unique gene expression profile of compared to both brown and white adipocytes. Therapies against obesity, targeting these cells and their pathways, would include the induction of lipolysis and apoptosis or the inhibition of differentiation and adipogenesis. However, it should be noted that both the increase of adipocyte size and number take place in association with positive energy balance. According to the adipose tissue expansion hypothesis, adipogenesis could be related with improved metabolic health of obese people, taking back the adipose mass to a traditionally site of lipid storage. Furthermore, new perspectives in fat biology suggest that the conversion of white-to-brown adipocytes and their metabolism could be exploited for the development of therapeutic approaches against obesity-associated diseases and for the regulation of energy balance. Drugs currently available to treat obesity generally have unpleasant side effects. A novel promising approach is the usage of dietary supplements and plant products that could interfere on the life cycle of adipocyte. Here, various dietary bioactive compounds that target different stages of adipocyte life cycle and molecular and metabolic pathways are reviewed.

The effect of chlorogenic acid on blood pressure: a systematic review and meta-analysis of randomized clinical trials

Several dietary supplements are currently marketed for management of hypertension, but the evidence for effectiveness is conflicting. Our objective was to critically appraise and evaluate the evidence for the effectiveness of chlorogenic acids (CGAs) on blood pressure, using data from published randomized clinical trials (RCTs). Electronic searches were conducted in Medline, Embase, Amed, Cinahl and The Cochrane Library. We also hand-searched the bibliographies of all retrieved articles. Two reviewers independently determined the eligibility of studies and extracted the data. The reporting quality of all included studies was assessed by the use of a quality assessment checklist adapted from the Consolidated Standard of Reporting Trials Statement. Disagreements were resolved through discussion. Seven eligible studies were identified, and five including 364 participants were included. There were variations in the reporting quality of the included RCTs. Meta-analysis revealed a statistically significant reduction in systolic blood pressure in favour of CGA (mean difference (MD): -4.31 mm Hg; 95% confidence interval (CI): -5.60 to -3.01; I(2)=65%; P<0.00001). Meta-analysis also showed a significant reduction in diastolic blood pressure favouring CGA (MD: -3.68 mm Hg; 95% CI: -3.91 to -3.45; I(2)=97%; P<0.00001). All studies reported no adverse events. In conclusion, the evidence from published RCTs suggests that CGA intake causes statistically significant reductions in systolic and diastolic blood pressures. The size of the effect is moderate. Few clinical trials have been conducted; they vary in design and methodology and are confined to Asian populations and funded by CGA manufacturers. Large independent trials evaluating the effects of CGA on blood pressure are warranted.

IQP-GC-101 reduces body weight and body fat mass: a randomized, double-blind, placebo-controlled study

IQP-GC-101 is a patented blend of the standardized extracts of Garcinia cambogia, Camellia sinensis, unroasted Coffea arabica, and Lagerstroemia speciosa. These individual ingredients of IQP-GC-101 have each shown promise in promoting weight loss; however, the efficacy of the blend has not been established. This randomized, placebo-controlled, double-blind, parallel group study conducted over 14 weeks (including a 2-week run-in phase) aimed to investigate the efficacy and safety of IQP-GC-101 in reducing body weight and body fat mass in overweight Caucasian adults. Subjects took three IQP-GC-101 or placebo tablets, twice a day, 30 min before main meals. All subjects also adhered to a 500 kcal/day energy deficit diet with 30% of energy from fat. Ninety-one overweight and mildly obese subjects (46 in the IQP-GC-101 group, 45 in the placebo group) completed the study. After 12-week intervention, IQP-GC-101 resulted in a mean (±SD) weight loss of 2.26 ± 2.37 kg compared with 0.56 ± 2.34 kg for placebo (pU  = 0.002). There was also significantly more reduction in body fat mass, waist circumference, and hip circumference in the IQP-GC-101 group. No serious adverse events were reported. The use of IQP-GC-101 has been shown to result in body weight and body fat reduction in the current study, with good tolerability.

Methanol extract of Melastoma malabathricum leaves exerted antioxidant and liver protective activity in rats

Background

Melastoma malabathricum L. (Melastomaceae) is a small shrub with various medicinal uses. The present study was carried out to determine the hepatoprotective activity of methanol extract of M. malabathricum leaves (MEMM) against the paracetamol-induced liver toxicity in rats model.

Methods

The respective chemicals and herbal solutions (10% DMSO, 200 mg/kg silymarin or MEMM (50, 250 and 500 mg/kg)) were administered orally to rats once everyday for 7 days followed by the hepatotoxicity assay. The blood samples and livers were collected and subjected to biochemical and microscopical analysis. Prior to the hepatoprotective study, MEMM was subjected to determination of the total phenolic content (TPC) and the antioxidant properties using several standard assays (e.g. 2, 2-diphenyl-1-picrylhydrazyl- and superoxide anion- radical scavenging assay, and oxygen radical absorbance capacity assay).

Results

MEMM exerted significant (p < 0.05) and high antioxidant activity in which high TPC was recorded; while in the hepatotoxicity study, the extract exhibited significant hepatoprotective effects against the paracetamol-induced hepatotoxic model. The results observed for serum liver enzymes (ALT, ALP and AST) as well as the microscopic observations and microscopic scoring supported the hepatoprotective potential of MEMM. The phytochemical and HPLC analysis of MEMM demonstrated the presence of flavonoids as its major constituents.

Conclusions

The MEMM-induced hepatoprotective activity could be allied partly to its antioxidant activity and the presence of flavonoids.

Roles of chlorogenic Acid on regulating glucose and lipids metabolism: a review

Intracellular glucose and lipid metabolic homeostasis is vital for maintaining basic life activities of a cell or an organism. Glucose and lipid metabolic disorders are closely related with the occurrence and progression of diabetes, obesity, hepatic steatosis, cardiovascular disease, and cancer. Chlorogenic acid (CGA), one of the most abundant polyphenol compounds in the human diet, is a group of phenolic secondary metabolites produced by certain plant species and is an important component of coffee. Accumulating evidence has demonstrated that CGA exerts many biological properties, including antibacterial, antioxidant, and anticarcinogenic activities. Recently, the roles and applications of CGA, particularly in relation to glucose and lipid metabolism, have been highlighted. This review addresses current studies investigating the roles of CGA in glucose and lipid metabolism.

Stimulation of postprandial fat utilization in healthy humans by daily consumption of chlorogenic acids

Long-term ingestion of coffee polyphenols (chlorogenic acids, CGAs) reduces body fat in humans and rodents. While CGA supplementation has been shown to increase fat utilization in rodents, evidence in humans is still limited. The present study clarifies the effect of daily CGA consumption on energy metabolism in humans. Eighteen healthy male subjects (36.1 ± 7.4 y of age) participated in a placebo-controlled, double-blind, crossover, intervention study with two different test beverages. The subjects consumed 185 mL of a test beverage with or without CGAs (329 mg) daily for 4 wk. The energy metabolism was evaluated by using indirect calorimetry before and after the test period during fasting and up to 180 min postprandially. Indirect calorimetry showed that a 4-wk ingestion of the CGA beverage led to a significantly higher postprandial energy expenditure than that of the control beverage. The subjects ingesting the CGA beverage exhibited higher postprandial fat utilization than those consuming the control beverage. The daily CGA consumption therefore increased postprandial fat utilization in healthy humans.

Disruption of the histidine triad nucleotide-binding hint2 gene in mice affects glycemic control and mitochondrial function

The histidine triad nucleotide-binding (HINT2) protein is a mitochondrial adenosine phosphoramidase expressed in the liver and pancreas. Its physiological function is unknown. To elucidate the role of HINT2 in liver physiology, the mouse Hint2 gene was deleted. Hint2(-/-) and Hint2(+/+) mice were generated in a mixed C57Bl6/J × 129Sv background. At 20 weeks, the phenotypic changes in Hint2(-/-) relative to Hint2(+/+) mice were an accumulation of hepatic triglycerides, decreased tolerance to glucose, a defective counter-regulatory response to insulin-provoked hypoglycemia, and an increase in plasma interprandial insulin but a decrease in glucose-stimulated insulin secretion and defective thermoregulation upon fasting. Leptin messenger RNA (mRNA) in adipose tissue and plasma leptin were elevated. In mitochondria from Hint2(-/-) hepatocytes, state 3 respiration was decreased, a finding confirmed in HepG2 cells where HINT2 mRNA was silenced. The linked complex II-III electron transfer was decreased in Hint2(-/-) mitochondria, which was accompanied by a lower content of coenzyme Q. Hypoxia-inducible factor-2α expression and the generation of reactive oxygen species were increased. Electron microscopy of mitochondria in Hint2(-/-) mice aged 12 months revealed clustered, fused organelles. The hepatic activities of 3-hydroxyacyl-coenzyme A dehydrogenase short chain and glutamate dehydrogenase (GDH) were decreased by 68% and 60%, respectively, without a change in protein expression. GDH activity was similarly decreased in HINT2-silenced HepG2 cells. When measured in the presence of purified sirtuin 3, latent GDH activity was recovered (126% in Hint2(-/-) versus 83% in Hint2(+/+) ). This suggests a greater extent of acetylation in Hint2(-/-) than in Hint2(+/+) .

CONCLUSION

Hint2/HINT2 positively regulates mitochondrial lipid metabolism and respiration and glucose homeostasis. The absence of Hint2 provokes mitochondrial deformities and a change in the pattern of acetylation of selected proteins.

Anti-diabetic and anti-lipidemic effects of chlorogenic acid are mediated by ampk activation

Chlorogenic acid (CGA) has been shown to stimulate glucose uptake in skeletal muscle through the activation of AMPK. However, its effect on other metabolic pathways and likewise its effects after long-term consumption have yet to be understood. We investigated the effects of CGA on glucose tolerance, insulin sensitivity, hepatic gluconeogenesis, lipid metabolism and skeletal muscle glucose uptake in Lepr(db/db) mice. Hepatoma HepG2 was used to investigate CGA's effect on hepatic glucose production and fatty acid synthesis. Subsequently, we attempted to evaluate whether these effects of CGA are associated with the activation of AMPK. In Lepr(db/db) mice, acute treatment with CGA lowered AUCglucose in an OGTT. Chronic administration of CGA inhibited hepatic G6Pase expression and activity, attenuated hepatic steatosis, improved lipid profiles and skeletal muscle glucose uptake, which in turn improved fasting glucose level, glucose tolerance, insulin sensitivity and dyslipidemia in Lepr(db/db) mice. CGA activated AMPK, leading to subsequent beneficial metabolic outcomes, such as suppression of hepatic glucose production and fatty acid synthesis. Inhibition and knockdown of AMPK abrogated these metabolic alterations. In conclusion, CGA improved glucose and lipid metabolism, via the activation of AMPK.

Biosynthesis, natural sources, dietary intake, pharmacokinetic properties, and biological activities of hydroxycinnamic acids

Hydroxycinnamic acids are the most widely distributed phenolic acids in plants. Broadly speaking, they can be defined as compounds derived from cinnamic acid. They are present at high concentrations in many food products, including fruits, vegetables, tea, cocoa, and wine. A diet rich in hydroxycinnamic acids is thought to be associated with beneficial health effects such as a reduced risk of cardiovascular disease. The impact of hydroxycinnamic acids on health depends on their intake and pharmacokinetic properties. This review discusses their chemistry, biosynthesis, natural sources, dietary intake, and pharmacokinetic properties.

Caffeine dose-dependently induces thermogenesis but restores ATP in HepG2 cells in culture

Caffeine has been hypothesised as a thermogenic agent that might help to maintain a healthy body weight. Since very little is known about its actions on cellular energy metabolism, we investigated the effect of caffeine on mitochondrial oxidative phosphorylation, cellular energy supply and thermogenesis in HepG2 cells, and studied its action on fatty acid uptake and lipid accumulation in 3T3-L1 adipocytes at concentrations ranging from 30-1500 μM. In HepG2 cells, caffeine induced a depolarisation of the inner mitochondrial membrane, a feature of mitochondrial thermogenesis, both directly and after 24 h incubation. Increased concentrations of uncoupling protein-2 (UCP-2) also indicated a thermogenic activity of caffeine. Energy generating pathways, such as mitochondrial respiration, fatty acid oxidation and anaerobic lactate production, were attenuated by caffeine treatment. Nevertheless, HepG2 cells demonstrated a higher energy charge potential after exposure to caffeine that might result from energy restoration through attenuation of energy consuming pathways, as typically found in hibernating animals. In 3T3-L1 cells, in contrast, caffeine increased fatty acid uptake, but did not affect lipid accumulation. We provide evidence that caffeine stimulates thermogenesis but concomitantly causes energy restoration that may compensate enhanced energy expenditure.

Facilitative effects of Eucommia ulmoides on fatty acid oxidation in hypertriglyceridaemic rats

BACKGROUND

Tea made from Eucommia ulmoides leaves is widely consumed as a health food, since recent studies have revealed various pharmacological effects of the tea, e.g. a hypotriglyceridaemic effect. This study was conducted to elucidate the mechanisms underlying the plasma triglyceride-lowering effect of E. ulmoides leaves.

RESULTS

Rats were divided into four groups: a normal group, a group fed a high-fat/high-fructose diet (untreated group) and two groups fed a high-fat/high-fructose diet and E. ulmoides tea (4 or 20 g L(-1) extract, treated groups). Plasma triglyceride concentrations were reduced in treated groups in a dose-dependent manner compared with the untreated group. DNA microarray analysis revealed that genes involved in hepatic α-, β- and ω-oxidation, mainly related to the peroxisome proliferator-activated receptor α and δ signalling pathway, were up-regulated in the treated group. High-performance liquid chromatography analysis showed that E. ulmoides leaves contain three phytochemicals that make up 60 mg g(-1) of the material and are likely to be the active components.

CONCLUSION

This study indicates that the promotion of fatty acid oxidation, probably by the action of phytochemicals, participates in the ameliorative effect of E. ulmoides leaves on hypertriglyceridaemia. These findings provide the scientific evidence for the functionality of E. ulmoides.

Randomized, double-blind, placebo-controlled, linear dose, crossover study to evaluate the efficacy and safety of a green coffee bean extract in overweight subjects

BACKGROUND

Adult weight gain and obesity have become worldwide problems. Issues of cost and potential side effects of prescription weight loss drugs have led overweight and obese adults to try nutraceuticals that may aid weight loss. One promising nutraceutical is green coffee extract, which contains high concentrations of chlorogenic acids that are known to have health benefits and to influence glucose and fat metabolism. A 22-week crossover study was conducted to examine the efficacy and safety of a commercial green coffee extract product GCA™ at reducing weight and body mass in 16 overweight adults.

METHODS

Subjects received high-dose GCA (1050 mg), low-dose GCA (700 mg), or placebo in separate six-week treatment periods followed by two-week washout periods to reduce any influence of preceding treatment. Treatments were counterbalanced between subjects. Primary measurements were body weight, body mass index, and percent body fat. Heart rate and blood pressure were also measured.

RESULTS

Significant reductions were observed in body weight (-8.04 ± 2.31 kg), body mass index (-2.92 ± 0.85 kg/m(2)), and percent body fat (-4.44% ± 2.00%), as well as a small decrease in heart rate (-2.56 ± 2.85 beats per minute), but with no significant changes to diet over the course of the study. Importantly, the decreases occurred when subjects were taking GCA. Body mass index for six subjects shifted from preobesity to the normal weight range (<25.00 kg/m(2)).

CONCLUSION

The results are consistent with human and animal studies and a meta-analysis of the efficacy of green coffee extract in weight loss. The results suggest that GCA may be an effective nutraceutical in reducing weight in preobese adults, and may be an inexpensive means of preventing obesity in overweight adults.

Differential transcriptomic profiles effected by oil palm phenolics indicate novel health outcomes

BACKGROUND

Plant phenolics are important nutritional antioxidants which could aid in overcoming chronic diseases such as cardiovascular disease and cancer, two leading causes of death in the world. The oil palm (Elaeis guineensis) is a rich source of water-soluble phenolics which have high antioxidant activities. This study aimed to identify the in vivo effects and molecular mechanisms involved in the biological activities of oil palm phenolics (OPP) during healthy states via microarray gene expression profiling, using mice supplemented with a normal diet as biological models.

RESULTS

Having confirmed via histology, haematology and clinical biochemistry analyses that OPP is not toxic to mice, we further explored the gene expression changes caused by OPP through statistical and functional analyses using Illumina microarrays. OPP showed numerous biological activities in three major organs of mice, the liver, spleen and heart. In livers of mice given OPP, four lipid catabolism genes were up-regulated while five cholesterol biosynthesis genes were down-regulated, suggesting that OPP may play a role in reducing cardiovascular disease. OPP also up-regulated eighteen blood coagulation genes in spleens of mice. OPP elicited gene expression changes similar to the effects of caloric restriction in the hearts of mice supplemented with OPP. Microarray gene expression fold changes for six target genes in the three major organs tested were validated with real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and the correlation of fold changes obtained with these two techniques was high (R2 = 0.9653).

CONCLUSIONS

OPP showed non-toxicity and various pleiotropic effects in mice. This study implies the potential application of OPP as a valuable source of wellness nutraceuticals, and further suggests the molecular mechanisms as to how dietary phenolics work in vivo.

The use of green coffee extract as a weight loss supplement: a systematic review and meta-analysis of randomised clinical trials

The purpose of this paper is to assess the efficacy of green coffee extract (GCE) as a weight loss supplement, using data from human clinical trials. Electronic and nonelectronic searches were conducted to identify relevant articles, with no restrictions in time or language. Two independent reviewers extracted the data and assessed the methodological quality of included studies. Five eligible trials were identified, and three of these were included. All studies were associated with a high risk of bias. The meta-analytic result reveals a significant difference in body weight in GCE compared with placebo (mean difference: −2.47 kg; 95%CI: −4.23, −0.72). The magnitude of the effect is moderate, and there is significant heterogeneity amongst the studies. It is concluded that the results from these trials are promising, but the studies are all of poor methodological quality. More rigorous trials are needed to assess the usefulness of GCE as a weight loss tool.

Chlorogenic acid exhibits anti-obesity property and improves lipid metabolism in high-fat diet-induced-obese mice

This study investigated the efficacy of chlorogenic acid on altering body fat in high-fat diet (37% calories from fat) induced-obese mice compared to caffeic acid. Caffeic acid or chlorogenic acid was supplemented with high-fat diet at 0.02% (wt/wt) dose. Both caffeic acid and chlorogenic acid significantly lowered body weight, visceral fat mass and plasma leptin and insulin levels compared to the high-fat control group. They also lowered triglyceride (in plasma, liver and heart) and cholesterol (in plasma, adipose tissue and heart) concentrations. Triglyceride content in adipose tissue was significantly lowered, whereas the plasma adiponectin level was elevated by chlorogenic acid supplementation compared to the high-fat control group. Body weight was significantly correlated with plasma leptin (r=0.894, p<0.01) and insulin (r=0.496, p<0.01) levels, respectively. Caffeic acid and chlorogenic acid significantly inhibited fatty acid synthase, 3-hydroxy-3-methylglutaryl CoA reductase and acyl-CoA:cholesterol acyltransferase activities, while they increased fatty acid beta-oxidation activity and peroxisome proliferator-activated receptors alpha expression in the liver compared to the high-fat group. These results suggest that caffeic acid and chlorogenic acid improve body weight, lipid metabolism and obesity-related hormones levels in high-fat fed mice. Chlorogenic acid seemed to be more potent for body weight reduction and regulation of lipid metabolism than caffeic acid.

Role of vegetable protein in the preparation of weight loss-promoting oil

We have reported that oil thermally processed with protein promoted safe and steady weight loss in animal experiments. In the present study, an oil for use in weight control was prepared by heating fresh oil with wheat gluten or soybean protein to determine the influence of protein differences on the weight loss-promotion effect. The 2 kinds of oil obtained, which differed neither from commercial fresh oil (starting oil) nor from one another in appearance, chemical properties, and aroma, were mixed (7%) with powdered AIN93G no-fat, defined standard diet and fed to 10-week-old Wistar rats ad libitum. After a 12-week feeding period, the rats were sacrificed to obtain blood and organs. There were no differences in amounts ingested, body weight increases, fecal excretion, organ weights, serum biochemical analyses, contents and fatty acid compositions of lipids of retroperitoneal fat tissue, or organ observations. Aspartate aminotransferase (AST), alanine aminotransferase (AST), and histological analysis supported the safety of the oil. In conclusion, the differences between wheat gluten and soybean protein in amino acid composition, both of the proteins and as free amino acids, were unrelated to the weight loss-promoting effect of the oil. Minor components in the vegetable proteins may have contributed to the effect on body weight.

Coffee, glucose homeostasis, and insulin resistance: physiological mechanisms and mediators

Epidemiological studies show coffee consumption to be correlated to large risk reductions in the prevalence of type 2 diabetes (T2D). Such correlations are seen with decaffeinated and caffeinated coffee, and occur regardless of gender, method of brewing, or geography. They also exist despite clear evidence showing that caffeine causes acute postprandial hyperglycemia and lower whole-body insulin sensitivity. As the beneficial effects of coffee consumption exist for both decaffeinated and caffeinated coffee, a component of coffee other than caffeine must be responsible. This review examines the specific coffee compounds responsible for coffee's effects on T2D, and their potential physiological mechanisms of action. Being plant-derived, coffee contains many beneficial compounds found in fruits and vegetables, including antioxidants. In fact, coffee is the largest source of dietary antioxidants in industrialized nations. When green coffee is roasted at high temperatures, Maillard reactions create a number of unique compounds. Roasting causes a portion of the antioxidant, chlorogenic acid, to be transformed into quinides, compounds known to alter blood glucose levels. Coffee consumption may also mediate levels of gut peptides (glucose-dependent insulinotropic polypeptide and glucagon-like peptide-1), hormones intimately involved in the regulation of satiety and insulin secretion. Finally, coffee may have prebiotic-like properties, altering gut flora and ultimately digestion. In summary, it is evident that a better understanding of the role of coffee in the development and prevention of T2D has the potential to uncover novel therapeutic targets and nutraceutical formulations for the disease.

Cecropia obtusifolia Bertol and its active compound, chlorogenic acid, stimulate 2-NBDglucose uptake in both insulin-sensitive and insulin-resistant 3T3 adipocytes

ETHNOPHARMACOLOGICAL IMPORTANCE

Cecropia obtusifolia Bertol (Cecropiaceae) is a plant extensively used for the empirical treatment of type 2 diabetes in México. Although some of its hypoglycemic principles have been described, their mechanisms of action remain unclear.

AIM OF THE STUDY

To investigate the anti-diabetic mechanisms of Cecropia obtusifolia aqueous extract (CAE) and its active compound chlorogenic acid (CGA).

MATERIALS AND METHODS

Non-toxic concentrations of CAE and CGA were assayed on the adipogenesis and 2-NBDglucose uptake in 3T3-F442A murine adipocytes.

RESULTS

Added to adipogenic medium, CAE 70 microg/ml induced a modest increment (20%) in 3T3 adipogenesis whereas CGA did not affect adipogenesis at any of the tested concentrations (0.1-100 microM). Both preparations stimulated 2-NBDG uptake in adipocytes by 51% (CAE) and 176% (CGA) in the absence of insulin, and by 174% (CAE) and 404% (CGA) in the presence of the hormone. CAE and CGA also stimulated the 2-NBDG uptake in insulin-resistant 3T3 adipocytes by 35% and 141%, respectively, compared with the incorporation shown by insulin-sensitive adipocytes stimulated by the hormone. The potency of CGA to stimulate 2-NBDG uptake was comparable to the anti-diabetic drug rosiglitazone.

CONCLUSION

Cecropia obtusifolia and CGA exert their anti-diabetic effects stimulating glucose uptake in both insulin-sensitive and insulin-resistant adipocytes without appreciable pro-adipogenic effects.

Chlorogenic acids from green coffee extract are highly bioavailable in humans

Chlorogenic acids (CGA) are cinnamic acid derivatives with biological effects mostly related to their antioxidant and antiinflammatory activities. Caffeoylquinic acids (CQA) and dicaffeoylquinic acids (diCQA) are the main CGA found in nature. Because green coffee is a major source of CGA, it has been used for production of nutraceuticals. However, data on the bioavailability of CGA from green coffee in humans are inexistent. The present study evaluated the pharmacokinetic profile and apparent bioavailability of CGA in plasma and urine of 10 healthy adults for 8 h after the consumption of a decaffeinated green coffee extract containing 170 mg of CGA. Three CQA, 3 diCQA, and caffeic, ferulic, isoferulic, and p-coumaric acids were identified in plasma by HPLC-Diode Array Detector-MS after treatment. Over 30% (33.1 +/- 23.1%) of the ingested cinnamic acid moieties were recovered in plasma, including metabolites, with peak levels from 0.5 to 8 h after treatment. CGA and metabolites identified in urine after treatment were 4-CQA, 5-CQA, and sinapic, p-hydroxybenzoic, gallic, vanillic, dihydrocaffeic, caffeic, ferulic, isoferulic, and p-coumaric acids, totaling 5.5 +/- 10.6% urinary recovery of the ingested cinnamic and quinic acid moiteties. This study shows that the major CGA compounds present in green coffee are highly absorbed and metabolized in humans.

Comparison of high performance TLC and HPLC for separation and quantification of chlorogenic acid in green coffee bean extracts

Two chromatographic methods, high-performance TLC (HPTLC) and HPLC, were developed and used for separation and quantitative determination of chlorogenic acid in green coffee bean extracts. For HPTLC silica gel Kieselgel 60 F 254 plates with ethyl acetate/dichlormethane/formic acid/acetic acid/water (100:25:10:10:11, v/v/v/v/v) as mobile phase were used. Densitometric determination of chlorogenic acid by HPTLC was performed at 330 nm. A gradient RP HPLC method was carried out at 330 nm. All necessary validation tests for both methods were developed for their comparison. There were no statistically significant differences between HPLC and HPTLC for quantitative determination of chlorogenic acid according to the test of equality of the means.