Vitamin C or ascorbic acid content has been determined by spectrophotometric method in fruits of some Bosnian hawthorns (Crataegus L). species. Spectrophotometric method used in this study is based on the kinetic reaction between Vitamin C and methylene blue. Measurements were carried out at absorption maximum, λmax= 665 nm. Titrimetric method was used as the reference method for comparison of the obtained results. We found that the lowest content of vitamin C was 106.12 mg/100 g of a dry sample in fruits of the C. monogyna, and the highest level of Vitamin C was found in the C. microphylla (231.96 mg/100 g of a dry sample) fruits. Recoveries of the results obtained by the spectrophotometric method were 101.4% 108.0% with relative standard deviation (RSD) values ranging between 0.40% 3.37%. Obtained results showed that fruits of studied Crataegus L. species are a good source of vitamin C with its potential to be used in food industry as the natural antioxidant.

The interest in polyphenolic antioxidants has increased remarkably in the last decades due to of their elevated capacity in scavenging free radicals associated with various human diseases. Previously, some fruits were shown to contain high antioxidant activities. Fifteen fruit juices were analyzed for total phenolic content and antioxidant capacity (oxygen radical absorbance capacity, ORAC). The total phenolic content (TPC) was measured by Folin-Ciocalteu assay and gallic acid used as standard. TPC varied from 7.3 mg GAE/100 mL for aloe vera juice to 71.8 mg GAE/100 mL for cranberry juice. The value of antioxidant capacity was determined by ORAC test, using 2,2'-azobis(2-amidino- propane) dihydrochloride as reactive species and Trolox as a standard. Obtained values were from 27.1 μmol TE/100 mL for aloe vera juice to 1271.8 μmol TE/100 mL for black currant juice. Results from the present study suggest further analysis on chemical composition of samples in order to identify compounds that might be responsible for antioxidant activity.