Bioactive properties of blueberry extracts obtained by different drying methods against Helicobacter pylori.

Helicobacter pylori (H. pylori) is widely recognised as one of the most prevalent human pathogens, which infects more than 50% of the population worldwide. Chronic inflammation of the gastric mucosa is one of the main consequences of this infection and is related to gastric cancer risk. Currently, due to the high association between H. pylori infection and the progression of gastric cancer, most therapeutic treatments aim to eradicate the bacteria using different antibiotics in combination with a proton pump inhibitor in a triple or quadruple therapy. However, resistant strains have increased significantly, requiring new therapeutic tools. Blueberries are rich in different bioactive compounds with antibacterial and anti-inflammatory properties that could contribute to reduce the problems associated with H. pylori infection. The aim of this research was to analyse the antibacterial and anti-inflammatory properties of different blueberry extracts obtained by different drying methods against H. pylori infection. Results showed that all blueberry extracts exhibited antibacterial effect against H. pylori, some of these extracts being bactericidal, while the rest reduced bacterial growth by more than 5 log CFU/mL. Bluecrop extracts were the most active, because all extracts obtained by the different drying methods resulted bactericidal. Extracts obtained by vacuum drying (VD) at 50ºC was the most effective since the extracts of the three varieties were bactericidal. Regarding anti-inflammatory activity, all blueberry extracts reduced IL-8 secretion in H. pylori-infected gastric cells. Bluecrop extracts obtained by VD at 70ºC and 90ºC reduced IL-8 production by 30% and 32%, respectively. These results suggest that blueberry extracts used in the present work and obtained by different drying methods could be a useful alternative to control H. pylori growth and in the modulation of the gastric inflammatory process induced in H. pylori infection.