Investigation of malatya apricot kernel in terms of bioactive substance content

In this study, 4 different apricot kernels hervested in 2 different years were utilized. The harvest year are 2018 and 2019; Malatya apricot species are Hacıhaliloğlu, Kabaaşı, Hasanbey and Zerdali. Analyzes were performed on apricot kernels, kernel extract and kernel hydrolyzate. Protein, ash, oil and moisture content were determined in apricot kernels. Total phenolic content and antioxidant activity were determined in apricot kernel extracts and kernel hydrolysates. Soluble protein amount, antimicrobial activity, amount of amygdalin, ACE-i activity and peptide sequence were determined in kernel hydrolysates. Pure water was used to extract the apricot kernel and trypsin was found the best enzyme for kernel hydrolysis. As a result of physicochemical analyzes, the highest dry matter ratio in Hacihaliloğlu, the highest ash ratio in Kabaaşı and the highest oil ratio in Hasanbey was found. Although the protein content was the highest in Hacıhaliloğlu, the highest amount of soluble protein was interestingly obtained in Hasanbey. ACE-i activity was analysed for different fractions of apricot kernel hydrolysates (namely below 3 kDa, 3 kDa and above). The highest ACE-i activity in peptides below 3 kDa was found in Hacihaliloğlu when the highest ACE-i activity of 3 kDa and above was found in Hasanbey. Three different methods were used to acquire amount of antioxidant activity of apricot kernels. Antioxidant activity in ABTS method was seen the highest in Zerdali when Hasanbey and Kabaaşı showed the highest antioxidant activity in the methods of FRAP and DPPH. The amount of amygdalin doesn't unexpectedly and statistically show a change amoung apricot kernel hydrolysate, however, Zerdali variety has higher amigdalin content than other apricot varieties. Two methods were utilized for antimicrobial activity analysis. The minimum inhibition concentration was 6 mg/mL against bacterial strains and 3 mg/mL against yeast strains. In disc diffusion method, it was obtained that apricot kernel hydrolysates have a catastrophic effect on microorganisms at a concentration of 20 mg/mL. Prunin 1 was detected as the storage protein in apricot kernel hydrolysate (except for Hacıhaliloğlu). Peptide fractions found in the kernel have aminoacid sequences possessing possible effect of antihypertensive, antioxidantive and DPP-IV inhibitory. R (arginine) amino acid residue was identified at the C-terminal of all peptides containing possible antihypertensive, antioxidantive and DPP-IV inhibitory effect. As a result of the research, it can be concluded that Hacıhaliloğlu and Hasanbey are the most suitable varieties in functional food production among the apricot kernels taken into the trial. Hasanbey variety has better physicochemical properties and antioxidant activity than Hacıhaliloğlu variety. But, Hacıhaliloğlu variety show higher ACE-i activity and contain more protein content.