Relationship between cannabinoids content and composition of fatty acids in hempseed oils.

Hempseed oils acquired on the Croatian markets were characterised by cannabinoid content and fatty acid composition. The new method for determination of cannabinoid content was developed and validated in the range of 0.05-60 mg/kg, and the content of tetrahydrocannabinol varied between 3.23 and 69.5 mg/kg. Large differences among the samples were obtained for phenotype ratio suggesting that not all of analysed hempseed oils were produced from industrial hemp. Sample clustering based on cannabinoid content assigned samples to two groups closely related to the phenotype ratios obtained. The results of this study confirm that hempseed oil is a good source of polyunsaturated fatty acids, especially γ-linolenic and stearidonic acid, but the content varies a lot more than the omega-6/omega-3 ratio. The grouping of samples on fatty acid content assigned samples to two groups which were consistent with the groups obtained based on cannabinoid content clustering.

Proteolytic activity of probiotic strain Lactobacillus helveticus M92.

The aim of this research was to investigate the potential of previously defined probiotic strain Lactobacillus helveticus M92 as functional starter culture for fermented dairy products. Therefore, proteolytic activity of L. helveticus M92 was investigated and compared with those of different representatives of probiotic and starter culture strains. Cluster analysis of AFLP fingerprints showed a difference of L. helveticus M92 compared to five other L. helveticus strains, but the percentage of similarity confirmed the identification on species level. Casein hydrolysis by L. helveticus M92 was monitored by agar-well diffusion test, SDS-PAGE and Anson's method. L. helveticus M92 exhibited the highest proteolytic activity among tested probiotic and starter cultures strains with the fastest acidification rate and the highest pH decrease after overnight incubation in skim milk. The presence of prtH2 gene was confirmed by PCR amplification with specific primers, while PCR product was not obtained after amplification with primers specific to prtH. Furthermore, SDS-PAGE LC-MS/MS analysis of insoluble proteome of L. helveticus M92 enabled identification of several proteins involved in proteolytic system of L. helveticus such as protease PrtM as well as proteins involved in Opp peptide transport system and the intracellular peptidases PepE, PepN, and PepQ.