Spectrophotometric ABTS Research Articles

Changes in Total Antioxidant Contents of Colostrum of Honamli and Hair Goat Breeds During the First 5 Days of Parturition

Colostrum is the primary source of initial acquired immunity and provides an antioxidative protection of newborn. The aim of present study was to analyze and compare the changes in total antioxidant capacity (TAC) and total phenolic contents (TPCs) colostrum’s of Honamli and Hair goat breeds on the first 5 days after parturition. The spectrophotometric ABTS method and the Folin–Ciocalteu assay were used. TAC and TPCs values were decreased gradually as the transition period advances. Both values were highest on the day first of calving as compared to rest of the days. Honamli goat colostrum samples had a higher TAC value than Hair goat and was showed significant (P less than 0.05) difference amongst the breeds. However, TPCs in Hair goat colostrum showed highly significant (P less than 0.05) difference than those of Honamli goat. In conclusion, TAC and TPC values in goat colostrum showed differences among goat breeds and exhibits daily rational changes.

Protocol of Proceedings with Fusobacterium Nucleatum and Optimization of ABTS Method for Detection of Reactive Oxygen Species

Aim: Characterization of the ability of Fusobacterium nucleatum DSM 15643 and DSM 20482 strains in the presence of Cu2+ and H2O2 to reactive oxygen species generation. Method: Spectrophotometric ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) method was used. Results: Determination of: MIC for Cu2+, H2O2 and ABTS; survivability of F. nucleatum under atmospheric oxygen exposure;the level and rate constants of free radicals production by the bacteria. Conclusion: F.nucleatum in the presence of Cu2+ and H2O2 is able to generate free radicals. Reactive oxygen species are produced mainly outside the bacterial cell, which suggests that outer membrane proteins may be involved in oxidative process.

Juices from non-typical edible fruits as health-promoting acidity regulators for food industry

The study verifies the possibility of application of juices from selected fruits characterized by the high antioxidant potential as natural acidity regulators with improved nutritional properties. The tested non-typical fruits included mirabelle plum, sea buckthorn and blue-berried honeysuckle. Beetroot juice whose pH is about 6.0 served as a model food product. Potentiometric titration was used to compare the efficacy of tested juices as acidity regulators with that of citric acid, a widely applied acidity regulator. The antioxidant activity of tested mixtures of juices was determined by spectrophotometric ABTS•+ (2,2-azinobis-(ethyl-2,3-dihydrobenzothiazoline-6-sulphonic acid) diammonium salt) test and their cytotoxic activity was assessed by MTT (thiazolyl blue tetrazolium bromide) test. The potentiometric titration revealed that the efficacy of the juices proposed as acidity regulators matched that of citric acid. Among the mixtures of beetroot juice and titrants studied, the addition of blue-berried honeysuckle juice ensured the highest antioxidant activity, followed by sea buckthorn and mirabelle plum juices. The same order was observed also for biological activity assessed in HT29 cells. The results of all tests confirmed that studied juices can successfully replace currently used acidity regulators, which may be of special interest in the case of functional foods.

Efecto Térmico del Secado por Aspersión sobre los Metabolitos Antioxidantes de la Curuba Larga (Passiflora mollisima baley)

In this study the antioxidant capacity and content of polyphenolic compounds in the fruit of Banana Passion Fruit (Passiflora mollisima Baley) before and after spray drying was evaluated. The high water content makes horticultural foods highly perishable and limited shelf life. Drying methods ensure microbiological stability of the fruit, although they may induce nutraceutical losses in the final product due to high temperatures used. The results revealed preservation of the antioxidant capacity determined by the spectrophotometric ABTS and DPPH techniques and by fluorescence ORAC assay, obtaining 77.3, 84.2 and 82.1 % respectively. The results suggest that the spray-drying is a suitable technique for dehydration of Banana Passion Fruit (Passiflora mollisima baley) and may be useful for other food matrices.