Total Antioxidant Capacity Of Foods Research Articles

The power of the QUENCHER method in measuring total antioxidant capacity of foods: Importance of interactions between different forms of antioxidants

Antioxidants play a crucial role in maintaining human health by counteracting oxidative stress and regulating redox balance within the body. The mixture of various antioxidant compounds in different forms (i.e., free, bound, insoluble) in food creates a redox active environment both in the human body and in the food system. Acting as both electron donors and acceptors while interacting with each other can either result in antagonism through pro-oxidative effects, or synergism through regeneration of one antioxidant by another. During the antioxidant capacity measurement, besides the individual antioxidant effects of the antioxidant components, these effects that occur because of their interaction with each other should be also considered. Classical antioxidant capacity measurement methods mostly concentrate on the fractions of foods that can be extracted with either water, alcohol, lipid, or acid/alkaline solutions. Antioxidants that cannot be extracted with any solvent are mostly ignored in these methods. On the other hand, the QUENCHER method, which allows direct measurement of antioxidant capacity foods without extraction, offers a rational solution to the limitations of traditional extraction-based methods. This approach considers the antioxidant capacity and interactions of all antioxidant forms that can be found in a food matrix, at the same time. This review provides detailed insights into the advantages of QUENCHER as a holistic approach for the accurate measurement of the antioxidant capacity of foods.

Evaluation of The Antioxidant Capacity of Food Products: Methods, Applications and Limitations

Assays of total antioxidant capacity (TAC) are popular in the analysis of food products. This review presents the most popular assays of TAC and their limitations, databases of TAC of food products, their application in clinical studies, and the effect of processing on the TAC of food. The importance of sample preparation for TAC assays and striking effects of digestion in the gastrointestinal tract on the TAC of food are discussed. Critical opinions on the validity of food TAC assays are considered. It is concluded that TAC methods can be useful as screening assays for food quality control and as low-cost, high-throughput tools used to discover potential antioxidant sources and follow changes in the content of antioxidants during food processing. However, effects revealed by TAC assays should be followed and explained using more specific methods.

The Gut Microbiota of Obese Children Releases Lower Antioxidant Capacity from Food than That of Lean Children.

The prevalence of obesity has been increasing in children over the last few decades, becoming a concern for health professionals and governments. Gut microbial community structure in obese people have been found to differ from that of lean subjects for some taxa which could result in different production of microbial metabolites. The aim of the present work was to study whether the gut microbiota from obese children extracts a different concentration of antioxidant capacity than the gut microbiota from lean children. For this purpose, different foods were in vitro digested and in vitro fermented using fecal material from obese and lean children. FRAP, DPPH and Folin-Ciocalteu methods were used to measure the antioxidant capacity released during digestion and fermentation. Overall, when using lean gut microbiota, antioxidant capacity released was higher when measured via DPPH and FRAP. Moreover, according to DPPH results, lean gut microbiota could potentially release more antioxidant power from vegetables than from animal products, while obese gut microbiota did the opposite. On the contrary, with the FRAP method obese gut microbiota released higher levels of antioxidant power from plant products than from animal products, but the final antioxidant capacity was still lower than that released by lean gut microbiota. Therefore, these results reflect that the total antioxidant capacity of foods is influenced by the gut microbiota, although whether that antioxidant capacity is released from plant or animal products can be slightly influenced by the method used for analysis.

Effect of food combinations and their co-digestion on total antioxidant capacity under simulated gastrointestinal conditions

This study aims to investigate the antioxidant interactions between mostly co-consumed foods in daily diet. Total antioxidant capacities of individual and the binary combinations of certain food samples from different groups including fruits, vegetables, grain sources, dairy and meat products were measured. The types of interactions (synergism, antagonism, and additive) between food samples were determined by a statistical comparison between estimated and measured total antioxidant capacity. The results revealed an antagonism in the combinations of milk with the fruits or green tea extract while a clear synergism was reported in the combination of fruits with breakfast cereal, whole wheat bread, or yoghurt. The selected foods were also subjected to in vitro digestion protocol. Slightly alkaline conditions were found to significantly (p < 0.05) increase the total antioxidant capacity of foods. Synergism was observed during the digestion of the combinations of milk with fruits or tea extracts. Hydroxyl radical scavenging capacity was also determined in the bioaccessible fractions of foods. Green tea extract was found to be the most efficient scavenger (936.48 ± 16.64 mmol TE.kg−1).

The Total Antioxidant Capacity Of Foods: A Reappraisal. Application To Commercial Orange Juices.

The Total Antioxidant Capacity Of Foods: A Reappraisal. Application To Commercial Orange Juices.

Dietary total antioxidant capacity and the risk of breast cancer: a case-control study.

There is growing evidence that dietary antioxidants may have favourable effects in reducing cancer risk. In a case-control study we investigated the association of dietary total antioxidant capacity (TAC) and risk of breast cancer. Sociodemographic data, medical history and anthropometric measurements were collected from 275 women (100 breast cancer cases & 175 controls). Participants' usual dietary intake was measured using a validated semi-quantitative food frequency questionnaire and their dietary TAC was estimated. An inverse, but non-significant, association was observed between dietary TAC and breast cancer risk. Multiple logistic regression models based on TAC of individual food groups showed that consumption of fruits and vegetables with higher TAC (μmolTE/100 g) was associated with a significantly decreased risk of breast cancer. Our study supports a protective effect of dietary antioxidants in relation to breast cancer risk. Food selection based on TAC of foods may be an effective strategy to modify the risk of cancer.

Solvent effects on total antioxidant capacity of foods measured by direct QUENCHER procedure

This study aimed to investigate the effects of solvent composition of different radicals (ABTS, DPPH) on measured total antioxidant capacity (TAC) of foods determined by the QUENCHER procedure. The working solutions of ABTS radical were prepared in the mixture of water–ethanol with different volume ratios (0:100, 25:75, 50:50, 75:25, 100:0). The solvent composition had a significant effect on the measured antioxidant capacity of various food matrices including cereals, fruits and vegetables, pulses and nuts (p<0.05). The use of ethanol alone gave the lowest values during measurement while introducing water to ethanol significantly improved the levels of antioxidant capacity. These results suggested that the mixture of water–ethanol (50:50, v/v) may be the most appropriate solution for standardizing the TAC database of foods tested by the QUENCHER procedure. The need of water is due to its ability to open the structure enabling better access of radicals to functional ends of the food matrices.

In Vitro 항산화능 측정법에 대한 특징 분석과 채소.과일 시료에 대한 적용 사례 고찰

건강한 삶에 대한 현대인의 관심이 나날이 고조되고 있으며, 이에 따라 노화와 질병의 예방에 효과가 있는 항산화제의 연구가 활발히 이루어지고 있다. 특히 천연물이나 식품을 소재로 한 식이성 항산화제에 대한 연구는 꾸준히 증가하고 있는 추세이며, 천연물의 소재나 연구 분야의 폭이 매우 넓다. 따라서 다양한 식품 소재의 항산화능을 조사할 수 있는 측정법의 중요성이 크게 부각되고 있다. 현재 약용 식물이나 상용 채소, 과일을 시료로 하여 여러 가지 radical이나 target molecule에 대한 항산화능을 측정할 수 있는 다수의 생체외(in vitro) 측정법이 사용되고 있다. 이에 본 총설에서는 널리 사용되고 있는 항산화능 측정법의 특징을 분석하고 적용 사례를 검토하였다. 식품의 구성 성분은 단일물질이 아닌 복합체로 구성되어 있으므로 하나의 측정법으로 항산화능을 평가할 수가 없다. 그러므로 채소와 과일을 포함한 여러가지 식물성 식품 추출물의 항산화 활성을 정확히 측정하기 위해서는 각 실험에 사용되는 radical과 기전(mechanism), 실험 조건(온도, pH, 실험기기, 시료추출방법, 소요 시간, 비용) 등을 고려하여 적절히 수행되어야 할 것이다. 그러나 이들 측정법의 다양성과 사용 단위의 차이로 인해 각 시료의 항산화능을 객관적으로 비교하는데 어려움이 있는 실정이다. 따라서 향후 항산화능 측정법의 표준화와 표현 단위의 통일이 절실히 요구된다. 또한 in vitro에서 항산화능을 나타내는 채소, 과일 등의 생체 내 활성은 다양한 biomechanism과 polymerphism으로 인해 그 효과를 예측하기가 매우 어렵다. 따라서 in vitro에서의 항산화능 screening 결과를 바탕으로 in vivo에서의 그 효과를 검증하는 연구가 부가적으로 시행되어야 할 것이라 사료된다.

MICROWAVE AND TRADITIONAL COOKING METHODS: EFFECT OF COOKING ON ANTIOXIDANT CAPACITY AND PHENOLIC COMPOUNDS CONTENT OF SEVEN VEGETABLES

ABSTRACT The effect of microwave, boiling and pressure cooking on total antioxidant capacity and total phenolics content of seven vegetables were studied. Total phenolics in raw and cooked vegetables were determined by the Folin–Ciocalteu method, whereas the total antioxidant capacity of vegetables extracts was evaluated using the Crocin method. After boiling, four out of seven vegetables (cauliflower, peas, spinach and Swiss chard) showed a significant decrease in their total phenolic content (P < 0.05). No decrease or a smaller decrease was observed for these four vegetables (P < 0.05) after pressure cooking and/or microwaving than after boiling. The total antioxidant capacity of potato and Swiss chard was not significantly affected by cooking procedures, whereas it decreased for spinach and peas, and it increased for tomato and carrots (P < 0.05). In addition, there was a statistically significant correlation between total phenolic content and total antioxidant capacity in cooked and uncooked vegetables, but the strength of the correlation increased when separating carotenoid-poor from carotenoid-rich vegetables. PRACTICAL APPLICATIONS All guidelines for a healthy nutrition include recommendation for increasing the consumption of fruit and vegetables also because of their phenolic compounds content and antioxidant capacity. However, all studies correlating antioxidants consumption and health benefits relate food consumption studies with antioxidant capacity of foods, neglecting to consider the chemical composition changes that may occur during cooking. This study provides data in order to better understand the implication on the total antioxidant capacity of foods due to different cooking approaches.

Dietary Total Antioxidant Capacity: A Novel Indicator of Diet Quality in Healthy Young Adults

Background: Overall diet quality measurements have been suggested as a useful tool to assess diet-disease relationships. Oxidative stress has been related to the development of obesity and other chronic diseases. Furthermore, antioxidant intake is being considered as protective against cell oxidative damage and related metabolic complications.Objective: To evaluate potential associations between the dietary total antioxidant capacity of foods (TAC), the energy density of the diet, and other relevant nutritional quality indexes in healthy young adults.Methods: Several anthropometric variables from 153 healthy participants (20.8 ± 2.7 years) included in this study were measured. Dietary intake was assessed by a validated food-frequency questionnaire, which was also used to calculate the dietary TAC and for daily energy intake adjustment.Results: Positive significant associations were found between dietary TAC and Mediterranean energy density hypothesis–oriented dietary scores (Mediterranean Diet Score, Alternate Mediterranean Diet Score, Modified Mediterranean Diet Score), non-Mediterranean hypothesis–oriented dietary scores (Healthy Eating Index, Alternate Healthy Eating Index, Diet Quality Index-International, Diet Quality Index-Revised), and diversity of food intake indicators (Recommended Food Score, Quantitative Index for Dietary Diversity in terms of total energy intake). The Mediterranean Diet Quality Index and Diet Quality Index scores (a Mediterranean and a non–Mediterranean hypothesis–oriented dietary score, respectively), whose lower values refer to a higher diet quality, decreased with higher values of dietary TAC. Energy density was also inversely associated with dietary TAC.Conclusion: These data suggest that dietary TAC, as a measure of antioxidant intake, may also be a potential marker of diet quality in healthy subjects, providing a novel approach to assess the role of antioxidant intake on health promotion and diet-based therapies.