Antioxidant activity of β-cyclodextrin inclusion complexes containing trans-cinnamaldehyde by DPPH,ABTS and FRAP

This study was carried out to observed β-cyclodextrin (β-CD) inclusion complexes containing trans-cinnamaldehyde (CIN) by using DPPH, ABTS and FRAP assay. Antioxidative ability was compared between pure CIN and β-CD-CIN inclusion complexes and particle size, encapsulation efficiency, and temperature-dependent release of inclusion complexes were investigated. High concentration of β-CD (1.8%) as well as guest oil 1:3 molar ratio (β-CD:CIN) influenced on particle size bigger during self-assembly process. And particle sizes were increased as storage period. In the antioxidant capacity results, pure β-CD (1.8%) was antioxidative without CIN especially at FRAP assay. Antioxidant activity dramatically increased after 1:1 molar ratio (1.8% β-CD:CIN), especially at DPPH assay and ABTS^•+ assay. In this study, β-CD complexation enhanced CIN solubility and affected increase the antioxidant activity of the CIN. Moreover, we need to consider that molar ratio of between β-CD concentration and CIN is effective manufacturing condition to improve antioxidant activity of β-CD-CIN inclusion complexes.     

Influence of some experimental variables and matrix components in the determination of antioxidant properties by β-carotene bleaching assay: experiments with BHT used as standard antioxidant

The β-carotene bleaching assay belongs to the oldest and continuously commonly applied methods of estimating the antioxidant activity of compounds and mixtures. In this method, the antioxidant activity of the examined substance is evaluated by the spectrophotometric measurement of β-carotene concentration changes in β-carotene/peroxyl radicals (LOO^•) systems with and without antioxidant. Yet a little is known about factors influencing the value of inhibition percent of the investigated antioxidant, estimated by this method. The paper shows that both the antioxidant solvent type and the amount of the antioxidant solvent in the measuring system significantly influence the inhibition percent value for butylohydroxytoluene (BHT), used as standard antioxidant in the performed experiments. Moreover, the results shown in the paper prove the essential influence of hydrogen and metal ions on the results of antioxidant assay. The relationships discussed in this paper indicate the necessity of standardizing β-carotene method and reveal the complexity of the problem of estimation of adequate antioxidant activity of examined substances.     

Changes in colour,antioxidant activities and carotenoids (lycopene, β-carotene,lutein) of marigold flower (Tagetes erecta L.) resulting from different drying processes

Marigold (Tagetes erecta L.) flower has long been used as a food colourant and ingredient in human food and animal feed. Drying is one of the most important processes for producing marigold powder. Therefore the effects of different drying processes, namely freeze drying (FD), hot air drying (HA) and combined far-infrared radiation with hot air convection (FIR-HA), on the colour, carotenoids (lycopene, β-carotene and lutein) and phenolic compounds of marigold flowers were evaluated. The results indicate that colour changes were less for FIR-HA dried marigold than after FD and HA drying. Different drying methods resulted in changes in the content of individual bioactive compounds. HA gave the highest content of β-carotene (15.5 mg/100 g dry weight (DW)), while FIR-HA and FD provided the highest levels of lutein and lycopene. The predominant phenolic acids in all samples of marigold are p-coumaric acid, ferulic acid and sinapic acid. Gallic, protocatechuic, caffeic, syringic, p-coumaric and ferulic acid showed the highest content in marigold after FIR-HA drying. These results demonstrate that FIR-HA should be considered as a suitable drying method for marigold with respect to preserving its colour, antioxidant properties and bioactive compounds and provided useful information for industrial production of marigold powder.     

Hydrolytic degree and antioxidant activity of purified casein characterised by different haplotypes (αs1-, β- and k-casein) after enzymatic hydrolysis with pepsin and enzymatic extract from Pleurotus eryngii

The aim of this study was to estimate the hydrolytic degree and antioxidant activity of purified casein characterised by different haplotypes (α_s1-, β- and k-casein) after in vitro digestion with two different enzymatic systems: pepsin from porcine gastric mucosa (EP) and a crude enzymatic extract from the edible mushroom Pleurotus eryngii. The used enzymes showed a different mode of casein catalysis with a consequent production of peptides of different antioxidant activity. The CN haplotype significantly influenced peptides production; in fact, the amino acid substitutions caused by genetic polymorphisms at the α_s1-, β- and k-CN loci influenced the sites of enzymatic cleavage and therefore the produced peptides. The above is evidenced by the different antioxidant activity found in the hydrolysates depending on the used enzymatic system, the CN haplotype, and the CN haplotype × enzymatic treatment interaction. The findings of this study are a perspective for the production of specific foods that exert a biological effect in addition to the nutritional one.