The Influence of Submerged Fermentation of Inonotus obliquus with Control Atmosphere Treatment on Enhancing Bioactive Ingredient Contents

NO Activates the Triterpenoid Biosynthetic Pathway in Inonotus obliquus Through Multilevel Signaling Regulation to Enhance Its Production

Triterpenoids are the bioactive components in Inonotus obliquus with extensive medicinal prospects, but their low content in fermentation production is the main limiting factor for their application. This study focuses on nitric oxide (NO), an important signaling molecule within organisms, aiming to explore its inducing effect on the synthesis of triterpenes in I. obliquus and the potential signaling transduction mechanisms involved. Compared with the control group, the content of representative triterpenoid betulin increased by 70.59% after adding the NO donor sodium nitroprusside. Gene expression level detection revealed that NO mainly promotes its biosynthesis by activating the transcription of key enzyme genes in the downstream pathway of betulin biosynthesis, thereby increasing its abundance. Tracing upstream, the NO signal was found to induce the upregulation of genes related to cellular antioxidant and calcium ion signaling pathways. Notably, IoCAMP responded strongly to the NO signal, participating in the regulation of cytoplasmic Ca2+ concentration by altering the Ca2+ concentration of mitochondria together with IoCATP and IoCALM. Additionally, the signaling of changes in Ca2+ concentrations is likely to crosstalk with the reactive oxygen species (ROS) signaling pathway. The increase in enzyme activity of IoNOX after NO induction confirmed the activation of the ROS signaling pathway. It works in synergy with IoSOD and IoCAT to reduce oxidative damage and promote downstream triterpenoid biosynthesis. This study not only contributes to clarify the signaling pathways regulating NO-mediated triterpenoid biosynthesis but also provides a theoretical basis for the efficient production of triterpenoid active components in I. obliquus.

Comparison of the Controlled Atmosphere Treatment for Submerged and Solid-State Fermentation of Inonotus obliquus

In this study, a controlled atmosphere (CA) treatment was used in the submerged (SM) and solid-state (SS) fermentation of Inonotus obliquus to determine the optimal conditions. The goal was to accelerate the artificial fermentation to obtain I. obliquus as an ingredient for dietary supplements. The results indicated that when CA treatment was used, the SM and SS fermentation of I. obliquus yielded polysaccharide and betulinic acid contents 2-2.5 times higher than those obtained when such treatment was not used. The two fermentation methods yielded similar outcomes in terms of DPPH scavenging ability, bioactivity, and antioxidant activity. Although SS fermentation yielded highly bioactive fruiting bodies when the period of fermentation was extended to 60 days, the mycelia produced by SM reached a similar bioactivity quality with only 30 days of fermentation. It was indicated that SM fermentation is more economically feasible than SS fermentation in the production of I. obliquus.

Selection and Genetic Analysis of High Polysaccharide-Producing Mutants in Inonotus obliquus

Inonotus obliquus, a medicinal fungus, has garnered significant attention in scientific research and medical applications. In this study, protoplasts of the I. obliquus HS819 strain were prepared using an enzymatic method and achieved a regeneration rate of 5.83%. To enhance polysaccharide production of I. obliquus HS819, atmospheric and room temperature plasma (ARTP) technology was employed for mutagenesis of the protoplasts. Through liquid fermentation, 32 mutant strains exhibiting diverse characteristics in morphology, color of the fermentation broth, mycelial pellet size, and biomass were screened. Secondary screening identified mutant strain A27, which showed a significant increase in polysaccharide production up to 1.67 g/L and a mycelial dry weight of 17.6 g/L, representing 137.67% and 15% increases compared to the HS819 strain, respectively. Furthermore, the fermentation period was reduced by 2 days, and subsequent subculture cultivation demonstrated stable polysaccharide production and mycelial dry weight. The genome resequencing analysis of the HS819 strain and mutant strain A27 revealed 3790 InDel sites and mutations affecting 612 functional genes associated with polysaccharide synthesis. We predict that our findings will be helpful for high polysaccharide production through genetic engineering of I. obliquus.

Advances in Production of Medicinal Mushrooms Biomass in Solid State and Submerged Bioreactors

Production of mushroom fruit bodies using farming technology could hardly meet the increasing demand of the world market. During the last several decades, there have been various basic and applied studies on fungal physiology, metabolism, process engineering, and (pre)clinical studies. The fundamental aspects of solid-state cultivation of various kinds of medicinal mushroom mycelia in various types of bioreactors were established. Solid-state cultivation of medicinal mushrooms for their biomass and bioactive metabolites production appear very suitable for veterinary use. Development of comprehensive submerged technologies using stirred tank and airlift bioreactors is the most promising technology for fast and large-scale production of medicinal fungi biomass and their pharmaceutically active products for human need. The potentials initiate the development of new drugs and some of the most attractive over-the-counter human and veterinary remedies. This article is to overview the engineering achievements in solid state and submerged cultivations of medicinal mushrooms in bioreactors.

Carbon Source Affects Synthesis, Structures, and Activities of Mycelial Polysaccharides from Medicinal Fungus Inonotus obliquus

The effects of various carbon sources on mycelial growth and polysaccharide synthesis of the medicinal fungus Inonotus obliquus in liquid fermentation were investigated. After 12-d fermentation, mycelial biomass, polysaccharide yield, and polysaccharide content were significantly higher in Glc+Lac group (glucose and lactose used as combined carbon source) than in other groups. Crude polysaccharides (CIOPs) and the derivative neutral polysaccharides (NIOPs) were obtained from mycelia fermented using Glc, fructose (Fru), Lac, or Glc+Lac as carbon source. Molecular weights of four NIOPs (termed as NIOPG, NIOPF, NIOPL, and NIOPGL) were respectively 780.90, 1105.00, 25.32, and 10.28 kDa. Monosaccharide composition analyses revealed that NIOPs were composed of Glc, Man, and Gal at different molar ratios. The NIOPs were classified as α-type heteropolysaccharides with 1→2, 1→3, 1→4, 1→6 linkages in differing proportions. In in vitro cell proliferation assays, viability of RAW264.7 macrophages was more strongly enhanced by NIOPL or NIOPGL than by NIOPG or NIOPF, and proliferation of HeLa or S180 tumor cells was more strongly inhibited by NIOPG or NIOPGL than by NIOPF or NIOPL, indicating that immune-enhancing and anti-tumor activities of NIOPs were substantially affected by carbon source. qRT-PCR analysis revealed that expression levels of phosphoglucose isomerase (PGI) and UDP-Glc 4-epimerase (UGE), two key genes involved in polysaccharide synthesis, varied depending on carbon source. Our findings, taken together, clearly demonstrate that carbon source plays an essential role in determining structure and activities of I. obliquus polysaccharides by regulating expression of key genes in polysaccharide biosynthetic pathway.

Implementation of food safety management systems that meets ISO 22000:2018 and HACCP: A case study of capsule biotechnology products of chaga mushroom

In our study, a food safety management system was developed for a chaga mushroom biotechnology product manufacturer, with the purpose of meeting the quality demands of customers and enhancing the manufacturer's reputation. The study focused on identifying the potentially significant hazards present at each stage of the production process for chaga mushroom capsule products, and on ensuring that the biotechnology company in question has fully implemented ISO22000:2018 and the HACCP methodology. The results indicate that, in the 1 year following the implementation of ISO 22000:2018, there was a statistically significant drop (P < 0.05) in the coliforms level of the tested biotechnology product samples that started in the ninth month following implementation. The rapid screening of mycotoxin, heavy metal, and pesticide residue levels also increased monitoring intensity and strengthened the periodic rotation plan, enabling control over potential problems relating to raw materials and ensuring product quality. This finding reveals the importance and necessity of rapid screening for small- and medium-sized food industry enterprises. Furthermore, 1 year after the system's implementation, the defect rate for chaga products was also observed to have declined, and the number of process flow anomalies requiring correction was also found to have decreased significantly (P < 0.05), indicating that safety and quality levels were improving and stabilizing. If implemented over a longer period of time, the food safety management system's benefits would stand out even more, and significant improvements would be observed for more monitored items. PRACTICAL APPLICATION: Few studies have touched on food safety management systems (FSMSs) developed for capsule health food products. The enterprise examined in this study had actively worked to improve its quality system and meet its customers' needs through the implementation of the FSMSs.