When breeding new hybrids, the composition of the berries may differ significantly from the parental plants, the differences in the amount and composition of polyphenols and anthocyanins also lead to changes in antimicrobial properties. The aim of our research is to evaluate the effects of components of newly bred hybrids of black, red currant, gooseberry and cherry on various microorganisms.
Research objects and methods. Antibacterial activity was evaluated by the agar diffusion method. Research microorganisms used for analysis: Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Kocuria rhizophila, Lactococcus lactis subsp. lactis, lactococcus lactis subsp. cremoris, Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium bifidum and two yeast species Sacharomyces cerevisiae, Rhodotorula rubra, isolated from equipment washes in food processing plants.
Results. The juices of black and red currants, cherry hybrids and gooseberry hybrids were analyzed. Currant and cherry hybrid berries differ in the composition of anthocyanins, antimicrobial properties of their extracts and juices. Gram-positive bacteria are effectively inhibited by extracts and juices, gram-negative bacteria are less sensitive, yeast and lactic acid bacteria are more resistant.
The growth of food poisoning agents L. monocytogenes and B. cereus was inhibited by all juices and their solutions, S. aureus was resistant to 10% juice of 2 hybrids, K. rhizophila, growth was not inhibited by 10% juice of four hybrids.
Analyzing the effect of the extracts on lactic acid bacteria, it appeared that the additives of cherry hybrid extracts in the medium affect them differently. L. lactis subsp. cremoris appeared to be sensitive to the effects of all extracts, the growth of B. bifidum was not inhibited by the extracts of any hybrid, the cell number dynamics did not differ from the control. L. delbrueckii subsp. bulgaricus and S. thermophilus growth was inhibited by extracts of one and two hybrids, respectively, L. lactis subsp. lactis showed the highest sensitivity, only the extracts of two studied hybrids had no effect on growth.
Project funding:
Research Council of Lithuania, National Research Programme „Healthy and Safe Food“
Project results:
When breeding new hybrids, the composition of the berries may differ significantly from the parental plants, the differences in the amount and composition of polyphenols and anthocyanins also lead to changes in antimicrobial properties. The aim of our research is to evaluate the effects of components of newly bred hybrids of black, red currant, gooseberry and cherry on various microorganisms.
Research objects and methods. Antibacterial activity was evaluated by the agar diffusion method. Research microorganisms used for analysis: Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Kocuria rhizophila, Lactococcus lactis subsp. lactis, lactococcus lactis subsp. cremoris, Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium bifidum and two yeast species Sacharomyces cerevisiae, Rhodotorula rubra, isolated from equipment washes in food processing plants.
Results. The juices of black and red currants, cherry hybrids and gooseberry hybrids were analyzed. Currant and cherry hybrid berries differ in the composition of anthocyanins, antimicrobial properties of their extracts and juices. Gram-positive bacteria are effectively inhibited by extracts and juices, gram-negative bacteria are less sensitive, yeast and lactic acid bacteria are more resistant.
The growth of food poisoning agents L. monocytogenes and B. cereus was inhibited by all juices and their solutions, S. aureus was resistant to 10% juice of 2 hybrids, K. rhizophila, growth was not inhibited by 10% juice of four hybrids.
Analyzing the effect of the extracts on lactic acid bacteria, it appeared that the additives of cherry hybrid extracts in the medium affect them differently. L. lactis subsp. cremoris appeared to be sensitive to the effects of all extracts, the growth of B. bifidum was not inhibited by the extracts of any hybrid, the cell number dynamics did not differ from the control. L. delbrueckii subsp. bulgaricus and S. thermophilus growth was inhibited by extracts of one and two hybrids, respectively, L. lactis subsp. lactis showed the highest sensitivity, only the extracts of two studied hybrids had no effect on growth.
Project coordinator: Kaunas University of Technology
