Beltrame Gabriele, Trygg Jani, Hemming Jarl, Han Zenghua, Yang Baoru
Food Chemistry and Food Development, Department of Life Technologies, University of Turku, Itäinen Pitkäkatu 4, FI-20520 Turku, Finland.
Wood and Paper Chemistry, Åbo Akademi University, Porthaninkatu 3, FI-20500 Turku, Finland.
J Fungi (Basel). 2021 Mar 8;7(3):189. doi: 10.3390/jof7030189.
The polysaccharides of the sterile conk of (Chaga) have demonstrated multiple bioactivities. The mycelium of this basidiomycete, obtained after submerged cultivation, has been considered a feasible alternative to the sterile conk for the production of polysaccharides. However, previous research has paid little attention to the differences in the structures of polymers obtained from the different resources. Moreover, the birch wood colonized by has never been investigated as a source of bioactive polysaccharides. In the present study, polysaccharide fractions produced from cultivated mycelium, sterile conks of different geographical origins, and birch heart rot were investigated. High amounts of phenolic compounds, possibly lignans, were bound to the sterile conk polysaccharides. Mycelial polysaccharides were rich in α- and β-glucans and had high (10 Da) and low (10 Da) molecular weight populations. On the other hand, sterile conk polysaccharides were mainly β-glucan of lower and monodispersed molecular weight (10 Da). Heart rot polysaccharides were comprised mainly of low molecular weight (10 Da) hemicelluloses. Nevertheless, fungal polysaccharides were identified in the extracts. The differences in structure and molecular properties among the polysaccharide fractions of mycelium, heart rot, and sterile conk are likely associated with differences in bioactivities and, therefore, in nutraceutical potential.
桦褐孔菌无菌子实体的多糖已显示出多种生物活性。通过深层培养获得的这种担子菌的菌丝体，被认为是生产多糖的无菌子实体的可行替代物。然而，以前的研究很少关注从不同来源获得的聚合物结构上的差异。此外，被桦褐孔菌定殖的桦木从未作为生物活性多糖的来源进行过研究。在本研究中，对由培养菌丝体、不同地理来源的无菌子实体以及桦木心材腐朽产生的多糖级分进行了研究。大量的酚类化合物，可能是木脂素，与无菌子实体多糖结合。菌丝体多糖富含α-和β-葡聚糖，具有高分子量（>10 kDa）和低分子量（<10 kDa）群体。另一方面，无菌子实体多糖主要是分子量较低且单分散的β-葡聚糖（<10 kDa）。心材腐朽多糖主要由低分子量（<10 kDa）的半纤维素组成。然而，提取物中鉴定出了真菌多糖。菌丝体、心材腐朽和无菌子实体的多糖级分在结构和分子性质上的差异可能与生物活性的差异有关，因此也与营养保健潜力有关。
