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Article
Publication date: 4 December 2019

Jaísa Oliveira Chaves, Angelica Maria de Freitas Fernandes, Paola Machado Parreiras, Gustavo Silveira Breguez, Maria Cristina Passos, Luciana Rodrigues da Cunha and Camila Carvalho Menezes

The purpose of this paper is to evaluate the effect of different times and freezing temperatures on the antioxidant activity of raw human milk (HM) and the impact of light…

Abstract

Purpose

The purpose of this paper is to evaluate the effect of different times and freezing temperatures on the antioxidant activity of raw human milk (HM) and the impact of light by different packaging on retinol level and the antioxidant activity of pasteurized HM.

Design/methodology/approach

Donor milks were homogenized to form the pool of the experimental study characterized by the evaluation of the effects of time (0, 2, 4, 8 and 15 days) freezing temperatures (−3°C, −8°C and −18°C) and the interference of the type of packaging on the antioxidant activity and retinol levels of HM.

Findings

The existing studies do not reveal the real impact of HM storage conditions adopted by human milk banks (HMB) in Brazil on their compounds, mainly in relation to the effects of temperature and freezing time and the incidence of light on retinol levels and antioxidant activity. In view of the already documented importance of these compounds for the growth, development and health of children, it is extremely important to assess their stability according to the procedures adopted by the banks. It has been observed in this study that lower freezing temperatures (−18°C) further preserve the antioxidant activity. It was found that the amber and transparent vials wrapped with aluminum foil allowed for greater retinol stability of HM, with values of 2.501±0.757 µmol/L and 4.991±0.825 µmol/L, respectively. On the contrary, there was no significant influence on antioxidant activity.

Originality/value

It is suggested that HMB store milk at lower temperatures and use glass jars that block the passage of light.

Details

British Food Journal, vol. 122 no. 2
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 1 March 1997

Nicholas J. Miller and Catherine A. Rice‐Evans

Examines the antioxidant activities of a range of hydroxy‐substituted phenolic acids by estimating their relative abilities to scavenge the ABTS_+ radical cation generated…

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Abstract

Examines the antioxidant activities of a range of hydroxy‐substituted phenolic acids by estimating their relative abilities to scavenge the ABTS_+ radical cation generated in the aqueous phase, expressed as the Trolox equivalent antioxidant capacity (TEAC value). These common food components have varying reducing abilities, dependent on the positions and extent of hydroxylation of their phenol ring. Reports the research results which suggest that some simple phenolic acids are most effective antioxidants, up to two to three times as active as vitamin C. Their relative abundance in fruits, oils, etc. indicates that they may be highly significant contributors to the overall dietary antioxidant intake. Para‐coumaric acid (4‐hydroxycinnamic acid) was found to have a TEAC value of 2.2mM (more than twice the antioxidant activity of vitamin C). Ferulic acid (3‐methoxy, 4‐hydroxycinnamic acid), the active component of oryzanol (rice bran oil) was found to have a TEAC value of 1.9 mM and gallic acid (3, 4, 5‐trihydroxybenzoic acid) a TEAC of 3.0mM (i.e. three times the antioxidant activity of vitamin C). Discusses the significance of these and other related compounds as food antioxidants and as non‐nutrient antioxidants in the diet.

Details

British Food Journal, vol. 99 no. 2
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 11 September 2020

Seok Shin Tan, Seok Tyug Tan and Chin Xuan Tan

Salak (Salacca zalacca) is an underutilised fruit. The bioactivities of this fruit have rarely been studied scientifically. Thus, the present study aimed to determine the…

Abstract

Purpose

Salak (Salacca zalacca) is an underutilised fruit. The bioactivities of this fruit have rarely been studied scientifically. Thus, the present study aimed to determine the antioxidant activity of extracts derived from the peel, fruit and kernel of the Salak fruit, as well as the hypoglycemic and anti-hypertensive properties of Salak peel extracts.

Design/methodology/approach

The peel, fruit and kernel of the Salak were extracted using distilled water, methanol and ethanol. Antioxidant activities, angiotensin-converting enzyme (ACE) and alpha-amylase inhibition properties of the extracts were estimated via in vitro standard methods. Besides, the total phenolic content (TPC) and total flavonoid content (TFC) of the extracts were also determined in the present study. The antioxidant activities of different parts of Salak extracts were determined by ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) methods. Percent of radical scavenging properties were calculated via DPPH assay. The hypoglycemic and anti-hypertensive properties of Salak peel were evaluated using alpha-amylase inhibition and ACE assays, respectively.

Findings

Fruit extracts of Salak in methanol were found to exhibit the highest TPC (10.27 ± 0.12 mg GAE/g), TFC (11.04 ± 0.89 mg CE/g) and antioxidant properties amongst all samples whereby the TPC and TFC were strongly correlated with antioxidant activities. On the other hand, distilled water extracted Salak kernel showed to have the lowest TPC (0.53 ± 0.05 mg GAE/g), TFC (0.37 ± 0.01 mg CE/g) and antioxidant properties amongst all the Salak extracts. Peel extracts exhibit comparable antioxidant activities with fruit extracts in the current findings. In addition, peel extracts indicated some extend of ACE and alpha-amylase inhibition activities regardless of the solvents used. Methanol and ethanol peel extracts indicated no significant difference (p < 0.05) ACE (98%) and alpha-amylase (90%) inhibition activities. However, distilled water extracted Salak peel showed significantly lower ACE and alpha-amylase inhibition in comparison to methanol and ethanol peel extracts.

Originality/value

The present findings suggested that the fruit of Salak exhibits the highest antioxidant properties, followed by the peel and lastly, the kernel, which shows the lowest antioxidant properties amongst all the samples. The results also indicated that the peel extracts have ACE and alpha-amylase inhibition activities.

Details

British Food Journal, vol. 122 no. 10
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 27 March 2009

Amin Ismail, Ngee‐Wen Tiong, Seok‐Tyug Tan and Azrina Azlan

The purpose of this paper is to determine the antioxidant properties (capacity and component) of four non‐leafy vegetables. The correlation between the antioxidant

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Abstract

Purpose

The purpose of this paper is to determine the antioxidant properties (capacity and component) of four non‐leafy vegetables. The correlation between the antioxidant capacity and its components of the studied vegetables was also assessed.

Design/methodology/approach

Winged beans, also known as four‐angled bean (Psophocarpus tetragonolobus), French bean (Phaseolus vulgaris), string bean (Vigna sinensis) and snow pea (Pisum sativum) were selected as samples from among the common non‐leafy vegetables consumed by Malaysians. These fresh vegetables were lyophilised and ground and their ethanolic extracts were prepared for antioxidant capacity assays and total phenolic, β‐carotene and ascorbic acid contents.

Findings

Among the vegetables, string beans showed the highest antioxidant capacity compared to the other vegetables studied (p < 0.05). The total phenolic, ascorbic acid and β‐carotene contents of snow peas were significantly higher (p < 0.05) than the other vegetables. There was a significant positive correlation between scavenging activity and antioxidant components studied. On the other hand, a negative correlation was found between antioxidant activity and its components of the studied vegetables.

Originality/value

Previous reports have indicated that vegetables contain high levels of antioxidants. However, data on antioxidant capacity of these non‐leafy vegetables are still lacking. This research paper shows the non‐leafy vegetables studied is a promising source of antioxidants with good antioxidant capacity. Beside that, along with the studied antioxidant components, other compounds in these vegetables could also contribute to their antioxidant capacity.

Details

Nutrition & Food Science, vol. 39 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 6 July 2012

Grzegorz Cieslar, Justyna Malyszek‐Tumidajewicz, Pawel Sowa and Aleksander Sieron

The purpose of this paper is to estimate the influence of long‐term, whole‐body exposure of rats to strong, static electric field with physical parameters generated nearby…

Abstract

Purpose

The purpose of this paper is to estimate the influence of long‐term, whole‐body exposure of rats to strong, static electric field with physical parameters generated nearby high voltage direct current (HVDC) transmission lines on the intensity of reactive oxygen species generation analyzed indirectly, basing on the measurement of malone dialdehyde level, as well as on the activity of enzymatic antioxidant defence system.

Design/methodology/approach

In rats exposed to static electric field with intensity of 16, 25 and 35 kV/m, respectively, or sham‐exposed eight hours daily for 56 days, in the obtained plasma, erythrocytes lysates and liver homogenates the activity of some antioxidant enzymes as well as the concentration of malone dialdehyde were determined with use of spectrophotometric and kinetic methods.

Findings

It was observed that long‐term exposure of rats to static electric field causes only temporary compensatory changes in the concentration of malone dialdehyde and transient changes in the activity of enzymatic antioxidant system, both in blood and in liver tissue in the form of temporary inhibition of activity of most antioxidant enzymes during exposure cycle, with subsequent compensatory increase in this activity after the end of exposure cycle, enabling maintenance of prooxidant‐antioxidant balance in the organism of experimental animals and inhibition of peroxidation process.

Practical implications

Presented data indicate that construction of air HVDC transmission lines, according to actual compulsory regulations, enables serious health hazards related to persistent disturbances of prooxidant‐antioxidant balance to be avoided.

Originality/value

In the experiment it was confirmed, for the first time, that long‐term exposure to strong static electric field causes transient compensatory changes of prooxidant‐antioxidant balance in living organisms.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 6 September 2011

Leonardo Fonseca Maciel, Cassiane da Silva Oliveira, Eliete da Silva Bispo and Maria da P. Spínola Miranda

Phenolic compounds, including flavonoids, are nutritionally important for their antioxidant activities and protective functions against disease risk caused by oxidative…

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Abstract

Purpose

Phenolic compounds, including flavonoids, are nutritionally important for their antioxidant activities and protective functions against disease risk caused by oxidative stress. These compounds are primarily found in fruits, and mangoes are an important source. This paper aims to address these issues.

Design/methodology/approach

In this work, the antioxidant activities of mangoes cultivated in three different ways were evaluated by their ability to capture free radicals using the DPPH radical.

Findings

The results showed that the biodynamic mangoes had highest antioxidant activity in mature‐green and ripe fruits, while for those of organic origin the antioxidant activity was highest in unripe fruits. The organic mangoes also showed highest values of phenolic compounds at all maturation stages. The mangoes from conventional crops had lower values for all parameters evaluated in this study than the organically and biodynamically cultivated fruits.

Originality/value

This work brings an important contribution in the field of agriculture at a time when organic and biodynamic systems of cultivation are an alternative to the conventional system and that pollutes the environment and produces food that contains quantities of chemical contaminants that can damage the health of the consumer. The comparison in phenolic compounds content, flavonoids and antioxidant activity in biodynamic, organic and conventional systems is original and of great importance, showing that the ecological cropping systems are less harmful to the environment and promote improvements to the chemical composition of foods.

Details

British Food Journal, vol. 113 no. 9
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 3 June 2019

Melek Çol Ayvaz, Figen Aksu and Filiz Kır

Mushrooms have always been treasured and appreciated, thanks to their nutritional as well as medicinal properties. The purpose of this paper is to reveal these properties…

Abstract

Purpose

Mushrooms have always been treasured and appreciated, thanks to their nutritional as well as medicinal properties. The purpose of this paper is to reveal these properties such as antioxidant activities and enzyme inhibition potentials of three mushroom species from Ordu, Turkey. Furthermore, phenolic profiles which are believed to be source of these properties are investigated.

Design/methodology/approach

The assays followed to determine total phenolic, flavonoid and antioxidant contents, antioxidative and enzyme inhibition activities are spectrophotometric methods. Phenolic profiles of mushroom samples were investigated by using the HPLC system.

Findings

The highest phenolic content was found for Lactarius deliciosus. Pyrogallol was the major phenolics in all three samples. Total phenolic content values supported that finding. But, total flavonoid content was the maximum for Cantharellus cibarius. The magnitude of the antioxidant activities revealed by the different tests varied between species. Furthermore, inhibition potential degrees on acetylcholinesterase, butrylcholinesterase, tyrosinase and urease activities were worth mentioning. Lactarius pyrogalus had anti-tyrosinase activity with a 26.229 percent inhibition rate. IC50 values for urease inhibition effect of mushroom samples were in the range of 0.37–0.90 mg/mL.

Originality/value

Enzyme inhibitory potentials for L. pyrogalus was revealed first time. On the other hand, studies on anti-tyrosinase activity of mushrooms are very rare, while almost no studies have been conducted on anti-urease activity. So, the results of present study are very valuable. Thus, the obtained data not only increase the ecological importance of the region but also provide significant contributions to the literature in terms of new sources rich in antioxidants.

Details

British Food Journal, vol. 121 no. 6
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 29 March 2011

Sinchan Biswas, Debabrata Sircar, Adinpunya Mitra and Bratati De

The purpose of this paper is to determine the antioxidant properties and phenol content of methanolic extracts of six white varieties and six purple/brown varieties of…

Abstract

Purpose

The purpose of this paper is to determine the antioxidant properties and phenol content of methanolic extracts of six white varieties and six purple/brown varieties of Indian rice and to find some relationship between the antioxidant properties, phenolic content in the varieties analyzed.

Design/methodology/approach

Methanolic extracts of different rice varieties were analyzed for their superoxide radical scavenging activity, 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging activity, total antioxidant capacity, reducing power and ferrous ion chelating properties. The extracts were analyzed for determination of total phenol content, anthocyanin content, oryzanol content. Phenolic acids were determined by HPLC.

Findings

All the rice varieties (white and purple/brown) showed activity in a dose‐dependent manner. Free phenolic acids, e.g. protocatechuic acid, caffeic acid, vanillic acid, p‐coumaric acid (PCA), ferulic acid and sinapic acid and the phenolic aldehyde vanillin could be detected in all the rice samples analyzed. No relationship could be established between activity and metabolite content. Principal component analysis and classification shows that superoxide radical scavenging activity, total phenolic acid, protocatechuic acid and ferulic acid are the components to differentiate the varieties from each other.

Originality/value

Little work has been done on the antioxidant activity of white rice. The authors report superoxide radical scavenging activity, DPPH radical scavenging activity, total antioxidant activity, reducing power and ferrous ion chelating properties and phenolic contents of six white varieties and six purple/brown varieties of Indian rice. Free phenolic acids like protocatechuic acid, caffeic acid, vanillic acid, PCA, ferulic acid and sinapic acid are reported from all the 12 varieties of rice.

Details

Nutrition & Food Science, vol. 41 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 14 October 2019

Devendra Pratap, Kumaresh Halder, Rakhi Singh, Ankur Ojha, Thangalakshmi S. and Savita Rani

Although milk is considered a vital source of nutrition for the livelihood, as the beginning of civilization, its antioxidant potential is required to be improved. This…

Abstract

Purpose

Although milk is considered a vital source of nutrition for the livelihood, as the beginning of civilization, its antioxidant potential is required to be improved. This paper aims to increase antioxidant activities in milk and soy milk (Glycine max L.) has been found as a good compatible source. Hence, the present work was planned to investigate the impact of blending of different proportions of soy milk with standardized milk (i.e. 50 per cent soy milk with 50 per cent standardized milk, 60 per cent soy milk with 40 per cent standardized milk, 70 per cent soy milk with 30 per cent standardized milk and 100 per cent standardized milk as control sample) on antioxidant properties and sensory attributes of the blends.

Design/methodology/approach

Antioxidant properties of the blends were determined in terms of 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power and total phenol content. Sensory evaluation was carried out using a nine-point hedonic scale based on four selected quality attributes (i.e. smell, taste, color and appearance and mouthfeel) and ranked for their quality traits by fuzzy modeling.

Findings

A blend containing 70 per cent soy milk with 30 per cent standardized milk showed the highest antioxidant activities as compared to control milk sample (p <0.05). Blend of 50 per cent soy milk with 50 per cent standardized milk was found most acceptable on the basis of sensory analysis and its antioxidant activities were also appreciable as compared to control milk sample (p <0.05). Smell, taste, color and appearance and mouthfeel influenced the acceptability of formulated milk samples in decreasing order of significance (p <0.05).

Originality/value

The present attempt has been made to formulate liquid milk by mixing standardized milk and soy milk, in which enhancement in the antioxidant activities of standardized milk and masking of off-flavor of soy milk is done. It is not done before and it may improve the nutritional and commercial value of the milk. Further, fuzzy modeling used for choosing appropriate blend in terms of sensory scores is also found as a novel approach.

Details

Nutrition & Food Science , vol. 50 no. 4
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 13 March 2017

Alexander Y. Yashin, Dmitry V. Yashunsky, Aleksander N. Vedenin, Nikolay E. Nifantiev, Yakov I. Yashin and Boris V. Nemzer

The purpose of this paper is to determine the antioxidant activity of natural polyphenols from larch wood by the amperometric method.

Abstract

Purpose

The purpose of this paper is to determine the antioxidant activity of natural polyphenols from larch wood by the amperometric method.

Design/methodology/approach

Direct measurements of antioxidant activity were carried out by the amperometric method in an oxidizing mode with glassy carbon as a working electrode, set potential +1.3V and using a flow-injection system with 2.2 mM phosphoric acid as the mobile phase with a flow rate of 1.2 ml/min.

Findings

The reported results show the following values of antioxidant activity for the tested compounds: (−)-secoisolariciresinol – 0.199 ± 0.002 mg/L (p < 0.05); isolariciresinol – 0.196 ± 0.002 mg/L (p < 0.05); lariciresinol - 0.222 ± 0.001 mg/L (p < 0.05); O-isopropylidene derivative of (−)-secoisolariciresinol - 0.143 ± 0.002 mg/L (p < 0.05); (+)-dihydroquercetin – 0.153 ± 0.002 mg/L (p < 0.05); and quercetin – 0.521 ± 0.001 mg/L (p < 0.05). The last product was tested as the reference of a widely used current antioxidant. General tendencies of determined values of antioxidant activity for studied compounds are in good correlation with published data as determined by the t-BuOOH-initiated lipid peroxidation method.

Practical implications

Described results show practical applicability of the amperometric method as being faster and cheaper in comparison to other methods, including oxygen radical absorbance capacity (ORAC) assay or 2,2′diphenyl-1-picrylhydrazyl (DPPH) reagent based assay.

Originality/value

The described results show the first-time application of the amperometric method for the evaluation of the antioxidant activity of phenolic compounds from larch wood.

Details

Nutrition & Food Science, vol. 47 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

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