Coffee Antioxidant Research Articles

The Impact of Self-Induced Anaerobic Fermentation (SIAF) on Coffee Antioxidants: A Review

The Impact of Self-Induced Anaerobic Fermentation (SIAF) on Coffee Antioxidants: A Review

Variables Affecting the Extraction of Antioxidants in Cold and Hot Brew Coffee: A Review.

Coffee beans are a readily available, abundant source of antioxidants used worldwide. With the increasing interest in and consumption of coffee beverages globally, research into the production, preparation, and chemical profile of coffee has also increased in recent years. A wide range of variables such as roasting temperature, coffee grind size, brewing temperature, and brewing duration can have a significant impact on the extractable antioxidant content of coffee products. While there is no single standard method for measuring all of the antioxidants found in coffee, multiple methods which introduce the coffee product to a target molecule or reagent can be used to deduce the overall radical scavenging capacity. In this article, we profile the effect that many of these variables have on the quantifiable concentration of antioxidants found in both cold and hot brew coffee samples. Most protocols for cold brew coffee involve an immersion or steeping method where the coffee grounds are in contact with water at or below room temperature for several hours. Generally, a higher brewing temperature or longer brewing time yielded greater antioxidant activity. Most studies also found that a lower degree of coffee bean roast yielded greater antioxidant activity.

Antioxidants in Coffee: An Exercise Using HPLC with Post-column Derivatization and Statistical Analysis

In today’s global economy, the origin of the food we eat is becoming more and more difficult to identify. Verifying the authenticity of products to protect supply chains is a complicated problem that requires a multidisciplinary approach. Chemical authentication of foodstuffs often includes a mass spectrometer detector; however, they are costly and require advanced operating skills. As an alternative, simple and robust post-column derivatization processes undertaken with HPLC may potentially provide chemical signatures of samples based upon the antioxidant profiles of the coffee samples. In this experiment, students employed a HPLC-PCD-VIS hyphenated separation protocol to produce a high-resolution chromatogram with minimal sample preparation, and the analysis was tuned to antioxidants in the coffee. Students encountered common analytical instruments and the commercially relevant CUPRAC assay. Using chromatographically derived data, students constructed MS Excel spreadsheets to normalize data and apply information theory to make statements about the similarity between coffee samples. Students were introduced to analytical protocols and chemometric techniques typical of 21st-century solutions to complex problems while utilizing common analytical instruments and reagents. Students were able to gain real-world laboratory skills, including running HPLC columns for sample analysis, method hyphenation, and signal retrieval. Students then utilized software to plot data for interpretation and to simplify data via preprocessing and chemometric operations to solve real-world problems.

Caffeine and the Risk of Diabetic Retinopathy in Type 2 Diabetes Mellitus: Findings from Clinical and Experimental Studies

The aim of this study was to assess the potential benefits of caffeine intake in protecting against the development of diabetic retinopathy (DR) in subjects with type 2 diabetes (T2D). Furthermore, we tested the effect of topical administration of caffeine on the early stages of DR in an experimental model of DR. In the cross-sectional study, a total of 144 subjects with DR and 147 individuals without DR were assessed. DR was assessed by an experienced ophthalmologist. A validated food frequency questionnaire (FFQ) was administered. In the experimental model, a total of 20 mice were included. One drop (5 μL) of caffeine (5 mg/mL) (n = 10) or vehicle (5 μL PBS, pH 7.4) (n = 10) was randomly administered directly onto the superior corneal surface twice daily for two weeks in each eye. Glial activation and retinal vascular permeability were assessed using standard methods. In the cross-sectional study in humans, the adjusted-multivariable model showed that a moderate and high (Q2 and Q4) caffeine intake had a protective effect of DR (odds ratio (95% confidence interval) = 0.35 (0.16-0.78); p = 0.011 and 0.35 (0.16-0.77); p = 0.010, respectively). In the experimental model, the administration of caffeine did not improve either reactive gliosis or retinal vascular permeability. Our results suggest a dose-dependent protective effect of caffeine in the development of DR, while the potential benefits of antioxidants in coffee and tea should also be considered. Further research is needed to establish the benefits and mechanisms of caffeinated beverages in the development of DR.

The Effect of Pre-Treatment of Arabica Coffee Beans with Cold Atmospheric Plasma, Microwave Radiation, Slow and Fast Freezing on Antioxidant Activity of Aqueous Coffee Extract

Thermal and non-thermal technologies used in food processing should be not only effective in terms of decontamination and preservation but also minimize undesirable losses of natural bioactive compounds. Arabica (Coffea arabica) is the most cultivated variety of coffee, making it a valuable source of phytonutrients, including antioxidants. In the present study, green and roasted Arabica coffee beans were treated with slow freezing (SF), fast freezing (FF), microwave radiation (MWR) and cold atmospheric plasma (CAP). Moisture content (MC) of coffee beans and antioxidant activity (AOA) of aqueous extracts were measured. Green coffee showed a decrease in MC after MWR treatment, and roasted coffee showed an increase in MC after freezing. After SF and FF at −19 °C for 24 h, all extract samples showed an increase in AOA by 4.1–17.2%. MWR treatment at 800 W for 60 s was accompanied by an increase in the AOA of green coffee extracts by 5.7%, while the changes in the AOA of roasted coffee extracts were insignificant. Sequential combined treatments of SF + MWR and FF + MWR resulted in an additive/synergistic increase in the AOA of green/roasted coffee extracts, up to +23.0%. After CAP treatment with dielectric barrier discharge (DBD) parameters of 1 μs, 15 kV and 200 Hz for 5 and 15 min, green coffee showed a decrease in the extract AOA by 3.8% and 9.7%, respectively, while the changes in the AOA of roasted coffee extracts were insignificant. A high positive correlation (r = 0.89, p < 0.001) between AOA and MC was revealed. The results obtained indicate that SF, FF, MWR and combined treatments may be applied at the pre-extraction stage of coffee bean preparation in order to increase the yield of antioxidant extractives.

Changes in the plasma lipidome of healthy subjects after coffee consumption reveal potential cardiovascular benefits: A randomized controlled trial

Lipid metabolism dysregulation is associated with cardiovascular disease (CVD) risk. Specific oxidized lipids are recognized CVD biomarkers involved in all stages of atherosclerosis, including foam cell formation. Moderate coffee intake is positively associated with cardiovascular health. A randomized, controlled (n = 25) clinical trial was conducted in healthy subjects to assess the changes in lipid species relevant to CVD (main inclusion criteria: coffee drinkers, nonsmokers, with no history and/or diagnosis of chronic disease and not consuming any medications). Volunteers consumed a coffee beverage (400 mL/day) containing either 787 mg (coffee A; n = 24) or 407 mg (coffee B; n = 25) of chlorogenic acids for eight weeks. We measured the total plasma levels of 46 lipids, including fatty acids, sterols, and oxysterols, at baseline and after eight weeks and assessed the effects of chlorogenic and phenolic acids, the major coffee antioxidants, in an in vitro foam cell model via targeted lipidomics. At baseline (n = 74), all participants presented oxysterols and free fatty acids (FFAs) (CVD risk markers), which are closely correlated to among them, but not with the classical clinical variables (lipid profile, waist circumference, and BMI). After eight weeks, the control group lipidome showed an increase in oxysterols (+7 ± 10%) and was strongly correlated with FFAs (e.g., arachidonic acid) and cholesteryl ester reduction (−13 ± 7%). Notably, the coffee group subjects (n = 49) had increased cholesteryl esters (+9 ± 11%), while oxysterols (−71 ± 30%) and FFAs (−29 ± 26%) decreased. No differences were found between the consumption of coffees A and B. Additionally, coffee antioxidants decreased oxysterols and regulated arachidonic acid in foam cells. Our results suggest that coffee consumption modulates the generation of oxidized and inflammatory lipids in healthy subjects, which are fundamental during CVD development. The clinical trial was registered on the International Clinical Trials Registry Platform, WHO primary registry (RPCEC00000168).

Improvement of Cardiac Fibrosis Biomarkers through Inflammation Inhibition by Green Tea and Decaffeinated Light Roasted Green Coffee Extract Combination Administration in Metabolic Syndrome Rat Model

Background: Metabolic syndrome is a significant risk factor for cardiovascular diseases. Green tea and green coffee extracts, antioxidant and anti-inflammatory agents may participate in metabolic syndrome-induced cardiac fibrosis alleviation. However, the effect of combination of those extracts still needs exploration. Therefore, this study investigated the effect of green tea and decaffeinated light roasted green coffee extracts and their combination in metabolic syndrome-induced cardiac fibrosis rats. Methods: Metabolic syndrome rat model was i1nduced through high-fat high sucrose diets feeding for 8 weeks and injection of low dose streptozotocin at the 2nd week. The metabolic syndrome rats were divided into 4 experimental groups metabolic syndrome rats (MS); metabolic syndrome rats treated with 300 mg/ kg b.w green tea extract (GT); metabolic syndrome rats treated with 200 mg/ kg b.w decaffeinated light roasted green coffee extract (GC); metabolic syndrome rats treated with the combination of the two extracts (CE); and a normal control (NC) group was added. Angiotensin 2 level was analyzed by ELISA method. Gene expression of NF-κB, TNF-α, IL-6, Tgf-β1, Rac-1, and α-sma were analyzed by touchdown polymerase chain reaction methods. Results: Metabolic syndrome rats treated with green tea and decaffeinated light roasted green coffee significantly decreased angiotensin-2 serum level and cardiac inflammation and fibrosis gene expression level (NF-κB, TNF-α, IL-6, Tgf-β1, Rac-1, and α-sma). More significant alleviation was observed in the combination group. Conclusion: This study suggested that combination of green tea and decaffeinated light roasted green coffee extracts showed better improvement in metabolic syndrome-induced cardiac fibrosis rat model compared to that of single extract administration through inflammation inhibition

Influence of dietary total antioxidant capacity on the association between smoking and hypertension in Brazilian graduates (CUME project)

Background and aimsHypertension (HTN) is a chronic non-communicable disease influenced by non-modifiable risk factors, such as sex and age, as well as modifiable risk factors such as lifestyle, including diet and smoking. Moreover, diet quality among smokers is worse than that of non-smokers, mainly in terms of antioxidant content. Thus, the current study aimed to investigate whether dietary total antioxidant capacity (dTAC) influences the association between smoking and HTN. Methods and resultsThis cross-sectional study included 4303 graduates (69.35% women) from the Cohort of Minas Gerais Universities (CUME) project. An online food frequency questionnaire was administered to participants, and dTAC was estimated using the ferric reducing antioxidant power method. In the questionnaires, individuals reported smoking status, systolic and diastolic blood pressure values, previous HTN diagnosis, and use of antihypertensive drugs. Logistic regression models were used to estimate the odds ratio and 95% confidence interval between smoking and HTN, stratified by the median dTAC. Current and former smokers had higher dTAC values despite their lower fruit intake. Moreover, coffee was the main contributor to dTAC among them. Smoking was associated with a higher likelihood of HTN, mainly among individuals with a higher dTAC. However, after exclusion of coffee antioxidant capacity, there was an association between only smoking and HTN in individuals with lower dTAC. ConclusionsThe controversial association between higher dTAC and HTN can result from high coffee intake. Higher dTAC without coffee intake may mitigate the association between smoking and HTN in this population.

Chemopreventative Potential of Plant-Based Extracts Coffee (Coffea) and Mauby (Colubrina Arborescens) using the Global Antioxidant Response (GAR) Method via in vitro Simulated Digestion

Plant-based extracts such as coffee (coffea) and Mauby (Colubrina Arborescens) were tested for chemopreventative potential by measuring their antioxidant activity (i.e., reducing power and free radical scavenging capacity) conventionally using chemical assays 1, 1-Diphenyl-2-picryl-hydrazyl (DPPH) and Ferric Reducing Antioxidant Power (FRAP). Alternately, extracts were also analyzed for their chemopreventative potential via a novel method (Global Antioxidant Response [GAR]), where they were subjected to simulated digestion before their antioxidant activity was determined via conventional methods previously mentioned. Next, the antioxidant capacities of the extracts, conventional versus the novel (GAR) method were compared. Overall, the analysis indicated that the reducing power (FRAP) and free radical scavenging capacity (DPPH) of coffee and Mauby were reduced (~16%) after undergoing simulated digestion. It was also observed that while the antioxidants in Mauby scavenged radicals at a significantly higher capacity than those in coffee (95.7% ± 0.67 and 90% ± 2.1 before digestion, and 77.7% ± 2.2 and 74.6% ± 2.3 after digestion, respectively), antioxidants in coffee exhibited higher reducing power compared to those in Mauby. Specifically, after undergoing simulated digestion, 1.12 mM FeSO4/mL ± 0.05 to 0.68 mM FeSO4/mL ± 0.07 ions were reduced before digestion, and 0.73 mM FeSO4/mL ± 0.09 to 0.48 mM FeSO4/mL ± 0.04 ions were reduced after digestion for coffee and Mauby, respectively. These findings suggest that while the antioxidants in coffee may have been more powerful in their ability to reduce ions, the antioxidants in Mauby may have been more effective in scavenging and neutralizing radicals.

Coffee antioxidants protect against liver damage in Non-alcoholic Fatty Liver Disease (NAFLD)

Coffee antioxidants protect against liver damage in Non-alcoholic Fatty Liver Disease (NAFLD)

Smartphone Application for Total Phenols Content and Antioxidant Determination in Tomato, Strawberry, and Coffee Employing Digital Imaging

A low-cost, simple method for in situ determination of total phenols and antioxidants in tomato, strawberry, and coffee through digital imaging was developed and validated. The determination of total phenolic was based on the chelation reaction between quercetin and ferric chloride forming a yellow complex. The antioxidants were quantified by the reaction between 2,6-di-tert-butyl-4-methylphenol, potassium ferricyanide, and ferric chloride, forming a bluish-green complex. After optimization, analytical curves were built to monitor the green color channel within the concentration range of 0 to 31.8 mg L−1 (r = 0.9969) and of 0 to 5 mg L−1 (r = 0.9995) for quercetin and 2,6-di-tert-butyl-4-methylphenol, respectively. The recovery of quercetin and 2,6-di-tert-butyl-4-methylphenol ranged from 96.48 to 101.11% and from 99.00 to 106.00%, respectively. Limits of detection and quantification were 0.03 and 0.11 for quercetin and 0.26 and 0.88 mg L−1 for 2,6-di-tert-butyl-4-methylphenol. The proposed method affords simple manipulation, fast response and environmental safety.

In Vitro Antibacterial and Antioxidant Activities of Roasted and Green Coffee Beans Originating from Different Regions of Ethiopia.

Coffee is among the most traded commodities and consumed beverages worldwide primarily for its stimulating effects. Moreover, coffee is known to contain various bioactive compounds with significant health benefits including antibacterial and antioxidant activities. However, Ethiopia as the origin of coffee and producer and exporter of varieties of Coffea arabica has made little study on the health aspects of this beverage. The aim of this study was to examine the antibacterial and antioxidant activities and content of coffee samples from different localities of Yorgacheffe and Jimma; and roasted, ground, and packed samples purchased from a coffee shop in Addis Ababa. Medium-roasted-boiled and lyophilized coffee extracts were tested on eight gram-negative and gram-positive bacterial strains. The agar-well diffusion method was used to test the extracts determining the minimum inhibitory and bactericidal concentrations. For coffee antioxidant activity and content, light-roasted (both field and shop samples) and green coffee bean extracts were tested using the free radical 2.2-diphenyl-l-pict1hydrazyl (DPPH) IC50 percent inhibition protocol. The samples showed strong antibacterial and antioxidant activity and substantial antioxidant content. Significant variation was noted in the antibacterial activities of the different coffee samples. Moreover, the growth-inhibitory strength of each coffee sample was variable for different test bacteria. A coffee sample with the best antibacterial activity had also the highest antioxidant activity/content. The shop coffee had the lowest bioactivity. The observed variations in the antibacterial and antioxidant activities among the samples probably indicate the diversity of the Ethiopian coffee related, among other factors, to the coffee plant genetics and agroecology.

Oxylipin regulation by phenolic compounds from coffee beverage: Positive outcomes from a randomized controlled trial in healthy adults and macrophage derived foam cells

Oxylipins are considered biomarkers related to cardiovascular diseases (CVDs). They are generated in vivo via the oxygenation of polyunsaturated fatty acids as a result of oxidative stress and inflammation. Oxylipins are involved in vascular functions and are produced during foam cell formation in atherogenesis. Additionally, the consumption coffee is associated with the regulation on a particular oxylipin group, the F2t-isoprostanes (F2t-IsoPs). This function has been attributed to the chlorogenic acids (CGAs) from the coffee beverage. Considering the anti-inflammatory and antioxidant properties of CGAs, we evaluated the effects of two types of coffee that provided 787 mg CGAs/day (Coffee A) and 407 mg CGAs/day (Coffee B) by reducing 35 selected oxylipins in healthy subjects. Furthermore, we assessed the effect of CGAs on the cellular proatherogenic response in foam cells by using an oxidized LDL (oxLDL)-macrophage interaction model. After eight weeks of coffee consumption, the contents of 12 urine oxylipins were reduced. However, the effect of Coffee A showed a stronger decrease in IsoPs, dihomo-IsoPs, prostaglandins (PGs) and PG metabolites, probably due to its higher content of CGAs. Neither of the two coffees reduced the levels of oxLDL. Moreover, the in vitro oxylipin induction by oxLDL on foam cells was ameliorated by phenolic acids and CGAs, including the inhibition of IsoPs and PGs by caffeoylquinic and dicaffeoylquinic acids, respectively, while the phenolic acids maintained both antioxidant and anti-inflammatory activities. These findings suggest that coffee antioxidants are strong regulators of oxylipins related to CVDs. The clinical trial was registered on the International Clinical Trials Registry Platform, WHO primary registry (RPCEC00000168).

Coffee capsules: implications in antioxidant activity, bioactive compounds, and aluminum content

The effect of new coffee brewing, coffee capsules, on the antioxidant activity (ORAC and ABTS), total phenolic content, chlorogenic acid, caffeine, and melanoidin concentration was assessed and compared with the conventional coffeemakers (filter, mocha, and expresso). In addition, the aluminum content was also analyzed to investigate the potential migration of this metal from the capsule to the beverages. The capsule method showed the lowest values of antioxidant capacity and total phenolic content. Capsule coffeemaker had the lowest extraction yield of the main coffee antioxidants (chlorogenic acid and melanoidins). On average, the highest amount of aluminum was obtained in decaffeinated coffees. Moreover, despite the fact that the coffee is considered to be a poor source of aluminum for humans, when the sample is decaffeinated, especially by Swiss Water® method and prepared by capsule machine, its aluminum content notably increases. The data collected provide useful insights for the selection of the type of coffee beverage with the major content of bioactive compounds and the minor content of harmful components for health.

Dietary Antioxidants in Coffee Leaves: Impact of Botanical Origin and Maturity on Chlorogenic Acids and Xanthones.

Natural polyphenols are important dietary antioxidants that significantly benefit human health. Coffee and tea have been shown to largely contribute to the dietary intake of these antioxidants in several populations. More recently, the use of coffee leaves to produce tea has become a potential commercial target, therefore prompting studies on the quantification of polyphenols in coffee leaves. In this study a variety of coffee leaf species, at different development stages, were analyzed using ultra-high pressure liquid chromatography. The results demonstrate that both the botanical origin of the samples and their maturity influence significantly the concentration of the antioxidants; for total chlorogenic acids a two-fold difference was found between different species and up to a three-fold variation was observed between young and mature leaves. Furthermore, the range of concentrations of chlorogenic acids in young leaves (35.7–80.8 mg/g of dry matter) were found to be comparable to the one reported for green coffee beans. The results provide important data from which potential new commercial products can be developed.

Information rich chromatographic separations of natural samples: The analysis of antioxidants in coffee using post column derivatisation and the CUPRAC assay on narrow bore reaction flow HPLC columns

In the present work, the CUPRAC PCD assay coupled to a narrow bore RF column (150 mm × 2.1 mm i.d., 5 µm particles) was tested on a variety of antioxidant standards and natural samples (coffee and decaffeinated coffee) to demonstrate the separation performance. As a result of being able to utilise narrow bore RF columns, several significant factors have been highlighted, including high resolution post column derivatisation assays and an approximate five-fold decrease in the volume of reagents (mobile phase and PCD reagents) resulting in a reduced cost of the analysis in terms of purchase price and waste disposal. Moreover, the CUPRAC antioxidant assay illustrates a variety of antioxidants in the coffee samples and also presents an extensive level of detection selectivity. Furthermore, the narrow bore RF PCD procedure reveals that caffeine was extracted from the coffee and yet a co-eluting antioxidant was not removed.

Review of the Role of Fluid Dairy in Delivery of Polyphenolic Compounds in the Diet: Chocolate Milk, Coffee Beverages, Matcha Green Tea, and Beyond

Abstract Dairy-based functional beverages have been a growing segment as consumer demands for health foods have shifted focus from simply enhancing lifespan to protecting health. Green tea is often limited in use because of poor bioavailability and disagreeable taste. However, milk is considered an ideal platform for the delivery of active polyphenolic compounds in green tea. Furthermore, the antioxidant enzymatic activity and antioxidant index of polyphenols in green tea have been known to be protected through interaction with dairy proteins inside the unstable intestinal environment. In addition, consumption of green tea infused with milk has been found to have a significant impact on reducing skin wrinkles and roughness in elderly subjects, through a decrease in lipid peroxidation and a concomitant reduction in oxidative stress. A similar affinity has been observed between antioxidants in coffee and milk proteins. Dark chocolate has been known to contain significant phenolic content and antioxidant activity. The activation of protein complex NF-κB, which is responsible for cell survival, was found to be significantly reduced upon consumption of cocoa with water, whereas consuming cocoa with milk had no effect on the bioavailability of the phenolic compounds in cocoa. The popularity of dairy as the source for polyphenol fortified beverages in the diet will be dictated by optimization of the technology for maximizing the bioavailability of the antioxidants.

Review of the Role of Fluid Dairy in Delivery of Polyphenolic Compounds in the Diet: Chocolate Milk, Coffee Beverages, Matcha Green Tea, and Beyond.

Dairy-based functional beverages have been a growing segment as consumer demands for health foods have shifted focus from simply enhancing lifespan to protecting health. Green tea is often limited in use because of poor bioavailability and disagreeable taste. However, milk is considered an ideal platform for the delivery of active polyphenolic compounds in green tea. Furthermore, the antioxidant enzymatic activity and antioxidant index of polyphenols in green tea have been known to be protected through interaction with dairy proteins inside the unstable intestinal environment. In addition, consumption of green tea infused with milk has been found to have a significant impact on reducing skin wrinkles and roughness in elderly subjects, through a decrease in lipid peroxidation and a concomitant reduction in oxidative stress. A similar affinity has been observed between antioxidants in coffee and milk proteins. Dark chocolate has been known to contain significant phenolic content and antioxidant activity. The activation of protein complex NF-κB, which is responsible for cell survival, was found to be significantly reduced upon consumption of cocoa with water, whereas consuming cocoa with milk had no effect on the bioavailability of the phenolic compounds in cocoa. The popularity of dairy as the source for polyphenol fortified beverages in the diet will be dictated by optimization of the technology for maximizing the bioavailability of the antioxidants.

The Potential of Liquid Tofu Waste in Increasing Antioxidant Activity of Robusta Green Coffee

Robusta is the most widely cultivated coffee in Indonesia (90% of the total Indonesian coffee production). Antioxidant activity and polyphenol content of Robusta coffee is higher than Arabica coffee or the other plants. One of the efforts, for coffee market expansion is product diversification through decaffeination of coffee . Decaffeination is one of process to reduce caffeine content. Decaffeinated coffee (decaff coffee) began to become public demand. In addition to its more delicious taste, low caffeine coffee is beneficial for health because it is safer to eat. Coffee decaffeination can utilize organic solvents that contain proteases. Tofu waste was one of protease sources. So that, tofu waste had potential as solvent in decaffeination The objective of the study was to assess the antioxidant activity of Robusta green coffee after going through decaffeination by using tofu waste. The study was used Factorial Completely Randomized Design, i.e . concentration of tofu waste (30%,60%, 90%) and length of immersion (3, 6, 9 hours). Robusta green coffee antioxidant activity was examined by using DPPH method. The results showed that the highest antioxidant activity ( 17.6061) was in the treatment of 90% waste concentration and 9 hours of decaffeination time. In conclusion, the greater the concentration and the longer the decaffeination resulted in the higher antioxidant activity. This study provides information about coffee processing methods that can produce coffee with the best quality. So, It can increasing the value of domestic coffee products especially in the global market and utilizing tofu liquid waste to be more malleable.

Cell‑specific and roasting‑dependent regulation of the Keap1/Nrf2 pathway by coffee extracts.

Coffee is a popular beverage that contains various bioactive compounds. However, its molecular mechanism of action is not fully elucidated. In this context, two previously characterized coffee extracts, a lightly roasted and the corresponding green one, were investigated for their effect on nuclear factor erythroid 2-related factor 2 (Nrf2) target gene expression in myoblasts and endothelial cells using quantitative PCR. The tested concentrations were non-cytotoxic and led to improved redox cell status, as was evident by increased reduced glutathione (GSH) levels. In both cell lines, the roasted extract upregulated gene expression more readily than its green counterpart leading to increased NAD(P)H quinone dehydrogenase 1 and γ-glutamyl cysteine ligase catalytic subunit, among others. The green extract had a mixed effect on the endothelial cells, while, as regards the myoblasts it caused the downregulation of some Nrf-target genes. Therefore, a potential dose- and roasting-dependent mechanism is proposed in the current study, accounting for coffee's antioxidant activity.