In vitro anti‐Helicobacter pylori activity of diallyl sulphides and protocatechuic acid

Abstract

The in vitro inhibitory effects of diallyl disulphide (DADS), diallyl trisulphide (DAT), roselle calyx extract and protocatechuic acid (PA) on the growth of Helicobacter pylori (15 susceptible, 11 clarithromycin-resistant and 9 metronidazole-resistant strains) were studied. The inhibition zone was determined after each agent had been heated at 25, 60, 100°C for 60 min. The minimal inhibitory concentration (MIC) of each agent was determined by the tube dilution assay. The results showed that heat treatment did not affect the anti-H. pylori activity of DADS, DAT, roselle calyx extract and PA, and the MIC values of these agents against test H. pylori strains were in the range 8 -64 mg/L. The time-kill study assay for DAT and PA at 1× × × × × MIC was monitored in Muller Hinton broth supplemented with 10% horse blood or mice stomach homogenate. Both DAT and PA inhibited the growth of all test H. pylori in broth and mice stomach homogenate ( p < < < < < 0.05); however, the inhibitory effects of these two agents were less in mice stomach homogenate than in broth (p < < < < < 0.05). DAT at 4, 6, 8, 10, 12, 14 mg/L and PA at 8, 16, 24, 32, 40, 48 mg/L were used for urease activity assay. These two agents significantly reduced urease activity of test H. pylori strains (p < < < < < 0.05), in which DAT and PA at 1× × × × × MIC reduced the urease activity of H. pylori to 70% and 40%, respectively. These agents, based on their lower MIC values and heat tolerance, might be useful in the prevention or therapy of H. pylori.

In Vitro Efficacy of Diallyl Sulfides against the Periodontopathogen Aggregatibacter actinomycetemcomitans

“…Unlike allicin, DASs are thermostable compounds and can be hypothesized to function effectively in the oral cavity. The inhibitory effect of DASs on several pathogens has been studied extensively (1,7,17,37,42,51,52,53,58,62,63), and recent reports have shown that DASs were synergistically effective against antibiotic-resistant strains when the DASs were combined with antibiotics (80). Our results also suggest that the anti-A.…”

“…These compounds possess potent anticancer, antioxidant, and anti-inflammatory immune modulation activities and antimicrobial properties (2,30,71,72,79,83). The inhibitory effect of DASs against Bacillus cereus, Salmonella sp., and Vibrio cholerae (7,62,63), Staphylococcus aureus and Candida albicans (42,51), Helicobacter pylori (52,58), and Klebsiella pneu-moniae and Pseudomonas aeruginosa (17,37,53,73) were studied, and a recent report has shown that DASs were synergistically effective when combined with antibiotics against antibiotic-resistant strains of Escherichia coli, Enterobacter cloacae, E. faecalis, and Citrobacter freundii (80). On the basis of the results of previous studies, we hypothesize that DAS is effective against A. actinomycetemcomitans and that it retains its activity even after heat treatment.…”

Protocatechuic Acid and Human Disease Prevention: Biological Activities and Molecular Mechanisms

“…This finding indicates that PCA might be useful in the prevention or therapy of H. pylori that is implicated in peptic ulcer, duodenal ulcer and gastric cancer [234].…”

Preparation and controlled-release studies of a protocatechuic acid-magnesium/aluminum-layered double hydroxide nanocomposite

“…Protocatechuic acid terminates these attacks through its scavenging and chelating activities. 28 Further, protocatechuic acid demonstrates other remarkable pharmacological activities such as anticancer, 29 antitumor, 30 antimutagenic, 31 antibacterial, 32 anti-inflammatory, 33 antigenotoxic, 34 cardioprotective, and chemopreventive. 35 It has been shown to cause markedly apoptotic effects in the treatment of several types of cancer cells, including human leukemia (pa-2000-leukemia), cervix, breast, lung, liver, and prostate.…”