Mechanism of butyl alcohol extract of Baitouweng Decoction (BAEB) on Candida albicans biofilms based on pH signal pathway / 中国中药杂志

This study aimed to investigate the effect of butyl alcohol extract of Baitouweng Decoction( BAEB) on Candida albicans biofilms based on pH signal pathway. The morphology of biofilms of the pH mutants was observed by scanning electron microscope. The biofilm thickness of the pH mutants was measured by CLSM. The biofilm activity of the pH mutants was analyzed by microplate reader.The biofilm damage of the pH mutants was detected by flow cytometry. The expression of pH mutant biofilm-related genes was detected by qRT-PCR. The results showed that the deletion of PHR1 gene resulted in the defect of biofilm,but there were more substrates for PHR1 complementation. BAEB had no significant effect on the two strains. RIM101 gene deletion or complementation did not cause significant structural damage,but after BAEB treatment,the biofilms of both strains were significantly inhibited. For the biofilm thickness,PHR1 deletion or complementation caused the thickness to decrease,after BAEB treatment,the thickness of the two strains did not change significantly. However,RIM101 gene deletion or complementation had little effect on the thickness,and the thickness of the two strains became thinner after adding BAEB. For biofilm activity,PHR1 deletion or complementation and RIM101 deletion resulted in decreased activity,RIM101 complementation did not change significantly; BAEB significantly inhibited biofilm activity of PHR1 deletion,PHR1 complemetation,RIM101 deletion and RIM101 complemetation strains. For the biofilm damage,PHR1 gene deletion or complementation,RIM101 gene deletion or complementation all showed different degrees of damage; after adding BAEB,the damage rate of PHR1 deletion or complementation was not significantly different,but the damage rate of RIM101 deletion or complementation was significantly increased. Except to the up-regulation of HSP90 gene expression,ALS3,SUN41,HWP1,UME6 and PGA10 genes of PHR1 deletion,PHR1 complementation,RIM101 deletion,and RIM101 complementation strains showed a downward expression trend. In a word,this study showed that mutations in PHR1 and RIM101 genes in the pH signaling pathway could enhance the sensitivity of the strains to the antifungal drug BAEB,thus inhibiting the biofilm formation and related genes expression in C. albicans.

Effects of butyl alcohol extract of Baitouweng Decoction on Candida albicans adhesion based on pH-mutant strains under acidic conditions / 中草药

Objective: To investigate the effect and mechanism of butyl alcohol extract of Baitouweng Decoction (BAEB) on adhesion of Candida albicans based on pH signaling pathway. Methods: Spot assay method was used to detect the sensitivity of pH mutants to BAEB under acidic conditions. XTT assay was used to detect the effect of BAEB on metabolic activity of pH mutants. The effect of BAEB on the adhesion activity of pH mutants was observed by fluorescence microscopy. The effect of BAEB on hydrophobicity of pH mutant was determined by n-octane inclusion method. The effect of BAEB on the expression of adhesion genes related to pH mutants was detected by qRT-PCR. Results: Under acidic conditions, spot assay observation showed that pH mutants were less sensitive to BAEB, 512 μg/mL BAEB interfered with pH mutants for 24 h and 48 h, there was no significantly decrease in bacterial colony. XTT assay showed that the metabolic activity of WT, PHR2 complementation, rim101/rim101 and RIM101 complementation was significantly inhibited in 512 μg/mL BAEB, and there was no significantly difference in the inhibition of phr2/phr2 metabolic activity. Fluorescence microscopy showed that the cell adhesion activity of WT, PHR2 complementation, rim101/rim101, RIM101 complementation was significantly inhibited in 512 μg/mL BAEB, the cell adhesion activity of phr2/phr2 had no obvious effect in 512 μg/mL BAEB. The n-octane inclusion method showed that the effect of 512 μg/mL BAEB on the cell surface hydrophobicity of WT, phr2/phr2, PHR2 complementation, rim101/rim101, RIM101 complementation was not significant. The qRT-PCR assay showed that the adhesion genes of pH mutants was inhibited in 1024 μg/mL BAEB. Conclusion: Under acidic conditions, the Candida albicans pH mutants was inhibited by BAEB to a certain extent.