Konsila Kawisara, Assavalapsakul Wanchai, Phuwapraisirisan Preecha, Chanchao Chanpen
Program in Biotechnology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand.
Department of Microbiology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand.
Heliyon. 2024 Apr 16;10(8):e29421. doi: 10.1016/j.heliyon.2024.e29421. eCollection 2024 Apr 30.
, a lipophilic pathogen, is known to be involved in various chronic skin diseases. Unfortunately, the available treatments have unwanted side effects and microbial drug resistance is evolving. As the antimicrobial activity of propolis is outstanding, this study aimed to examine the potential of propolis from the stingless bee against the yeast. Anti- growth activity was ascertained in agar well diffusion and broth microdilution assays and the inhibitory concentration value at 50 % (IC) was determined. Since the yeast cannot synthesize its own fatty acids, extracellular lipase is important for its survival. Here, anti- extracellular lipase activity was additionally investigated by colorimetric and agar-based methods. Compared to the crude hexane and crude dichloromethane extracts, the crude methanol partitioned extract (CMPE) exhibited the best anti- growth activity with an IC of 1.22 mg/mL. After CMPE was further enriched by silica gel column chromatography, fraction CMPE1 (IC of 0.98 mM or 184.93 μg/mL) presented the highest activity and was later identified as methyl gallate (MG) by nuclear magnetic resonance analysis. Subsequently, MG was successfully synthesized and shown to have a similar activity, and a minimal fungicidal concentration of 43.44 mM or 8.00 mg/mL. However, lipase assay analysis suggested that extracellular lipase might not be the main target mechanism of MG. This is the first report of MG as a new anti- compound. It could be a good candidate for further developing alternative therapeutic agents.
一种亲脂性病原体，已知与多种慢性皮肤病有关。不幸的是，现有的治疗方法有不良副作用，且微生物耐药性正在不断演变。由于蜂胶具有出色的抗菌活性，本研究旨在检测无刺蜂蜂胶对该酵母的潜在作用。通过琼脂孔扩散法和肉汤微量稀释法确定了抗生长活性，并测定了50%抑制浓度值（IC）。由于该酵母无法合成自身脂肪酸，细胞外脂肪酶对其生存至关重要。在此，还通过比色法和基于琼脂的方法对抗细胞外脂肪酶活性进行了研究。与正己烷粗提物和二氯甲烷粗提物相比，甲醇分配粗提物（CMPE）表现出最佳的抗生长活性，IC为1.22 mg/mL。CMPE经硅胶柱色谱进一步富集后，组分CMPE1（IC为0.98 mM或184.93 μg/mL）表现出最高活性，随后通过核磁共振分析鉴定为没食子酸甲酯（MG）。随后，成功合成了MG，并显示其具有相似活性，最小杀菌浓度为43.44 mM或8.00 mg/mL。然而，脂肪酶测定分析表明，细胞外脂肪酶可能不是MG的主要作用靶点机制。这是关于MG作为一种新型抗化合物的首次报道。它可能是进一步开发替代治疗药物的良好候选物。
