Paduano Stefania, Marchesi Isabella, Valeriani Federica, Frezza Giuseppina, Facchini Maria Chiara, Romano Spica Vincenzo, Bargellini Annalisa
Department of Biomedical, Metabolic and Neural Sciences, Section of Public Health, University of Modena and Reggio Emilia, Via Campi 287, 41125, Modena, Italy.
Department of Movement, Human, and Health Sciences, Public Health Unit, University of Rome "Foro Italico", Rome, Italy.
Microb Ecol. 2024 Dec 5;87(1):152. doi: 10.1007/s00248-024-02469-x.
Peloids are made by mixing clay materials with thermo-mineral waters, enriched with organic substances from microorganisms during maturation. Their beneficial properties may depend on clay minerals, water characteristics, and microbial components, although strong evidence is lacking. Next Generation Sequencing (NGS) allows a comprehensive approach to studying the entire microbial community, including cultivable and uncultivable bacteria. Our study aims to characterize, by NGS, the bacterial community overall and during the maturation process of thermal muds in two spas (A-B) of an Italian thermal complex. Peloids were produced from sulfurous-bromine-iodine thermal water and clay material: natural mud for spa A and sterile clay for spa B. Thermal waters and peloids at different maturation stages (2/4/6 months) were analyzed for microbiome characterization by 16S amplicon sequencing. Biodiversity profiles showed a low level of similarity between peloids and water used for their maturation. Peloids from spa A showed greater microbial richness than those from spa B, suggesting that natural mud with an existing bacterial community leads to greater biodiversity than sterile clay. Genera involved in sulfur metabolism were prevalent in both spas, as expected considering peloids matured in sulfide-rich water. For all three maturation stages, the prevalent genera were Thiobacillus and Pelobacter in spa A and Thiobacillus, Thauera, Pelobacter, and Desulfuromonas in spa B. Richness and diversity indices showed that the community seemed to stabilize after 2-4 months. The 16S amplicon sequencing to study bacterial communities enables the identification of a biological signature that characterizes a specific thermal matrix, defining its therapeutic and cosmetic properties. The bacterial composition of peloids is affected by the thermal water and the type of clay material used in their formulation and maturation.
泥疗剂是通过将粘土材料与热矿泉水混合制成的，在成熟过程中富含微生物产生的有机物质。尽管缺乏有力证据，但其有益特性可能取决于粘土矿物、水的特性和微生物成分。新一代测序（NGS）为研究整个微生物群落提供了一种全面的方法，包括可培养和不可培养的细菌。我们的研究旨在通过NGS对意大利一个温泉综合体的两个温泉（A - B）中热泥的细菌群落整体以及成熟过程进行表征。泥疗剂由含硫 - 溴 - 碘的热水和粘土材料制成：A温泉使用天然泥，B温泉使用无菌粘土。对不同成熟阶段（2/4/6个月）的热水和泥疗剂进行16S扩增子测序，以分析微生物群落特征。生物多样性图谱显示，泥疗剂与其成熟所用的水之间相似度较低。A温泉的泥疗剂比B温泉的泥疗剂显示出更高的微生物丰富度，这表明含有现有细菌群落的天然泥比无菌粘土能带来更高的生物多样性。考虑到泥疗剂在富含硫化物的水中成熟，两个温泉中参与硫代谢的属都很普遍。在所有三个成熟阶段，A温泉中普遍存在的属是硫杆菌属（Thiobacillus）和泥杆菌属（Pelobacter），B温泉中是硫杆菌属、陶厄氏菌属（Thauera）、泥杆菌属和脱硫单胞菌属（Desulfuromonas）。丰富度和多样性指数表明，群落似乎在2 - 4个月后趋于稳定。通过16S扩增子测序研究细菌群落能够识别表征特定热基质的生物特征，从而确定其治疗和美容特性。泥疗剂的细菌组成受热水以及其配制和成熟过程中所用粘土材料类型的影响。
