Effect Of Hinokitiol Research Articles

Searching for the role of membrane lipids in the mechanism of antibacterial effect of hinokitiol

The aim of this work was to investigate the effect of monoterpenoid hinokitiol (β-thujaplicin) on the monolayers and bilayers composed of lipids typical for bacteria membranes and gain insight into the potential role of the lipids in antibacterial activity and selectivity of this compound. To explore this issue, the in vitro studies were performed on different bacterial strains to verify antibacterial potency of hinokitiol. Then, the experiments on E. coli and S. aureus bacteria membrane models (i.e. model multicomponent monolayers and bilayers) were done. Finally, the effect of hinokitiol on one component lipid monolayers was investigated. The lipids used in the experiments included Phosphatidylethanolamines (PEs), Phosphatidylglycerols (PGs) and Cardiolipins differing in the structure of the polar head and/or the hydrophobic chains. This choice allowed the analysis of correlations between the lipid structure and the effect of hinokitiol.In vitro tests confirmed the antimicrobial activity of hinokitiol against most of the strains tested. In addition, the in vitro tests showed that E. coli bacteria were more sensitive to hinokitiol than S. aureus bacteria. Interestingly, the studies on model systems evidenced that hinokitiol molecules are of stronger effect on E.coli film and they are able to insert into these systems even at membrane-related surface pressures. Moreover, the structure of the lipid and its content in the model system correlated with the effect exerted by hinokitiol on the monolayer properties. It was found that hinokitiol differs in the affinity to particular lipids and additionally hinokitiol/lipid interactions may occur according to different mechanisms. Namely, depending on the lipid structure, hinokitiol may incorporate into the lipid film (Cardiolipins and PEs) or interact preferentially with the lipid polar head (PGs) and form hydrogen bonds. The effect of hinokitiol on the lipids was determined by the charge and size of the polar head as well as by the spatial size of the lipid molecule. Moreover, comparing the lipids of the same polar heads, hinokitiol caused stronger expansion of the film formed from the lipid having unsaturated chains. The results obtained may explain the difference in the effect of hinokitiol on particular bacterial strains. In conclusions, it can be suggested that the lipids should be considered as the bacteria membrane structural elements of a possible role in the mechanism of action of hinokitiol.

Efficacy and potential mechanism of hinokitiol against postharvest anthracnose of banana caused by Colletotrichum musae

Anthracnose caused by Colletotrichum musae is a devastating post-harvest disease on bananas, and it leads to serious economic losses. Exploring environmentally friendly natural compounds to manage anthracnose in fruit has been attracting more attention. In the current study, the effect of hinokitiol against C. musae and on banana quality was investigated. Our results showed that hinokitiol exhibited promising antifungal activities both in vitro and in vivo. Importantly, it effectively delayed banana ripening by maintaining weight, color, firmness, and TSS content, and it dramatically reduced the release of ethylene, the respiration rate, and the expression of genes involved in releasing ethylene. Moreover, the activities of defense-related enzymes including SOD, POD, and APX were enhanced by hinokitiol. The mechanism of hinokitiol against C. musae may be attributed to the destruction on the integrity of the plasma membrane, which leads to the leakage of cellular constituents and eventually the cell death of C. musae. Taken together, this study provided substantial evidence that hinokitiol had great potential to be developed as a natural antifungal agent against C. musae, prolonging the storage period of postharvest bananas.

Hinokitiol increases the angiogenic potential of dental pulp cells through ERK and p38MAPK activation and hypoxia-inducible factor-1α (HIF-1α) upregulation

Hinokitiol, a natural iron-chelating agent, is known to have diverse biological and pharmacological activities in various cell types. However, the effect of hinokitiol on dental pulp cells has not yet been reported. In this study, hinokitiol increases hypoxia-inducible factor-1α (HIF-1α) protein levels and vascular endothelial growth factor (VEGF) secretion in human dental pulp cells. The extracellular-signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) pathways are involved in hinokitiol-induced HIF-1α protein expression in dental pulp cells. Conditioned media from hinokitiol-treated pulp cells enhances angiogenesis in vitro and in vivo. Overall, these results show that hinokitiol promotes ERK and p38MAPK activation and HIF-1α-induced VEGF production, thus increasing the angiogenic potential of dental pulp cells.

Masking effect of Hinokitiol, a woody odor, on predator odor-induced stress-related activation

Masking effect of Hinokitiol, a woody odor, on predator odor-induced stress-related activation

Evaluation of the practicability of hinokitiol as a repellent against the cigarette beetle, Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae)

The strong repellency of hinokitiol (β-thujaplicine) to the cigarette beetle was reported in a previous paper. In this study, the practicability of using hinokitiol as a repellent against the beetle was evaluated. The effect of hinokitiol on the behavioral response of the beetle to food-attractant lure was observed with a video system. The frequency of the beetle approaching the hinokitiol-treatment filter paper on which a food-attractant lure was placed was much less than that to the control filter paper. The resident time on the treatment paper was also much less than that on the control paper. Filter paper tapes treated with hinokitiol prevented the beetles from entering the sticky trap with food-attractant lure when the tapes were attached near the entrance of the trap. Furthermore, repellency of hinokitiol was evaluated in a semi-field test. Tapes treated with hinokitiol attached around the openings of the cardboard boxes containing cured tobacco leaves prevented the beetles from entering the boxes. The number of beetles entering the treatment boxes was less than half that of the control boxes. It appears that hinokitiol is a useful repellent against the cigarette beetle.