Variations of the fungal microbiome in Corydalis Rhizoma with different collection areas, processing methods, and storage conditions.

Corydalis Rhizoma (CR, Yanhusuo in Chinese) has been widely used as an analgesic in herbal medicine and functional food. Cases of fungal and mycotoxin contamination in CR have been reported. In this study, the composition and diversity of fungal microbiome in CR samples from four herbal markets and two processing methods were investigated by DNA metabarcoding. Variations of the fungal microbiome in CR during cold and conventional storage were monitored. Results showed that Aspergillus was the dominant genus and saprotroph was the dominant trophic mode. Six potential toxigenic fungi, namely, Aspergillus fumigatus, Aspergillus ostianus, Aspergillus terreus, Penicillium citrinum, Penicillium oxalicum, and Trichothecium roseum, were detected. Differences in fungal composition and diversity among various groups based on collection areas and processing methods were also observed. Moreover, the relative abundance of dominant genera in CR samples stored at different temperatures was significantly different and changed with storage time. This study is the first to reveal the influence of collection areas, processing methods, and storage conditions on the fungal microbiome in CR, which was expected to provide a basis for control strategies of fungal contamination in the industrial chain of CR.

DNA metabarcoding analysis of fungal community on surface of four root herbs.

Objective: Angelicae Sinensis Radix (ASR, Danggui in Chinese), Cistanches Herba (CH, Roucongrong in Chinese), Ginseng Radix et Rhizoma (PG, Renshen in Chinese), and Panacis Quinquefolii Radix (PQ, Xiyangshen in Chinese), widely used as medicine and dietary supplement around the world, are susceptible to fungal and mycotoxin contamination. In this study, we aim to analyze their fungal community by DNA metabarcoding. Methods: A total of 12 root samples were collected from three main production areas in China. The samples were divided into four groups based on herb species, including ASR, CH, PG, and PQ groups. The fungal community on the surface of four root groups was investigated through DNA metabarcoding via targeting the internal transcribed spacer 2 region (ITS2). Results: All the 12 samples were detected with fungal contamination. Rhizopus (13.04%-74.03%), Aspergillus (1.76%-23.92%), and Fusarium (0.26%-15.27%) were the predominant genera. Ten important fungi were identified at the species level, including two potential toxigenic fungi (Penicillium citrinum and P. oxalicum) and eight human pathogenic fungi (Alternaria infectoria, Candida sake, Hyphopichia burtonii, Malassezia globosa, M. restricta, Rhizopus arrhizus, Rhodotorula mucilaginosa, and Ochroconis tshawytschae). Fungal community in ASR and CH groups was significantly different from other groups, while fungal community in PG and PQ groups was relatively similar. Conclusion: DNA metabarcoding revealed the fungal community in four important root herbs. This study provided an important reference for preventing root herbs against fungal and mycotoxin contamination.

DNA Metabarcoding Reveals the Fungal Community on the Surface of Lonicerae Japonicae Flos, an Edible and Medicinal Herb.

Lonicerae Japonicae Flos (LJF) has been globally applied as an herbal medicine and tea. A number of reports recently revealed fungal and mycotoxin contamination in medicinal herbs. It is essential to analyze the fungal community in LJF to provide an early warning for supervision. In this study, the fungal community in LJF samples was identified through DNA metabarcoding. A total of 18 LJF samples were collected and divided based on the collection areas and processing methods. The results indicated that Ascomycota was the dominant phylum. At the genus level, Rhizopus was the most abundant, followed by Erysiphe and Fusarium. Ten pathogenic fungi were detected among the 41 identified species. Moreover, Rhizopus, Fusarium, and Aspergillus had lower relative abundances in LJF samples under oven drying than under other processing methods. This work is expected to provide comprehensive knowledge of the fungal community in LJF and a theoretical reference for enhanced processing methods in practical manufacturing.

Intracellular TMEM16A is necessary for myogenesis of skeletal muscle.

Transmembrane protein 16A (TMEM16A) localizes at plasma membrane and controls chloride influx in various type of cells. We here showed an intracellular localization pattern of TMEM16A molecules. In myoblasts, TMEM16A was primarily localized to the cytosolic compartment and partially co-localized with intracellular organelles. The global deletion of TMEM16A led to severe skeletal muscle developmental defect. In vitro observation showed that the proliferation of Tmem16a-/- myoblasts was significantly promoted along with activated ERK1/2 and Cyclin D expression; the myogenic differentiation was impaired accompanied by the enhanced caspase 12/3 activation, implying enhanced endoplasmic reticulum (ER) stress. Interestingly, the bradykinin-induced Ca2+ release from ER calcium store was significantly enhanced after TMEM16A deletion. This suggested a suppressing role of intracellular TMEM16A in ER calcium release whereby regulating the flux of chloride ion across the ER membrane. Our findings reveal a unique location pattern of TMEM16A in undifferentiated myoblasts and its role in myogenesis.