A sensitive, precise and rapid LC-MS/MS method for determination of ergosterol peroxide in Paecilomyces cicadae mycelium

The Hyphosphere of Leaf-Cutting Ant Cultivars Is Enriched with Helper Bacteria

Bacteria can live in a variety of interkingdom communities playing key ecological roles. The microbiome of leaf-cutting attine ant colonies are a remarkable example of such communities, as they support ants' metabolic processes and the maintenance of ant-fungus gardens. Studies on this topic have explored the bacterial community of the whole fungus garden, without discerning bacterial groups associated with the nutrient storage structures (gongylidia) of ant fungal cultivars. Here we studied bacteria isolated from the surface of gongylidia in the cultivars of Atta sexdens and Acromyrmex coronatus, to assess whether the bacterial community influences the biology of the fungus. A total of 10 bacterial strains were isolated from gongylidia (Bacillus sp., Lysinibacillus sp., Niallia sp., Staphylococcus sp., Paenibacillus sp., Pantoea sp., Staphylococcus sp., and one Actinobacteria). Some bacterial isolates increased gongylidia production and fungal biomass while others had inhibitory effects. Eight bacterial strains were confirmed to form biofilm-like structures on the fungal cultivar hyphae. They also showed auxiliary metabolic functions useful for the development of the fungal garden such as phosphate solubilization, siderophore production, cellulose and chitin degradation, and antifungal activity against antagonists of the fungal cultivar. Bacteria-bacteria interaction assays revealed heterogeneous behaviors including synergism and competition, which might contribute to regulate the community structure inside the garden. Our results suggest that bacteria and the ant fungal cultivar interact directly, across a continuum of positive and negative interactions within the community. These complex relationships could ultimately contribute to the stability of the ant-fungus mutualism.

Isolation, purification, and structural elucidation of Stropharia rugosoannulata polysaccharides with hypolipidemic effect

Stropharia rugosoannulata is a widely grown edible mushroom with a high nutritional value. S. rugosoannulata polysaccharides is one of the most important bioactive components of S. rugosoannulata and has a wide range of activities. A S. rugosoannulata polysaccharides, named SRF-3, was derived from the S. rugosoannulata extraction by freeze-thaw combine with hot water extraction method, then prepareed with DEAE-cellulose column and Sephacryl S-200 HR gel column, and its hypolipidemic activity was determined. The structural characteristics of SRF-3 were analyzed by infrared spectral scanning (FT-IR), ultra-high performance liquid chromatography (UHPLC), acid hydrolysis, methylation analysis, nuclear magnetic resonance (NMR), and Gas Chromatography-Mass Spectrometer (GC-MS). SRF-3 is composed of mannose, galactose, methyl galactose and fructose with ratios of 16, 12, 58 and 12, respectively. In addition, the average relative molecular mass of SRF-3 is approximately 24 kDa. The main chain of SRF-3 is mainly composed of repeating α-D-1,6-Galp and α-D-1,6-Me-Galp units, with branches in the O-2 position of Gal. The structure is presumed to be a mannogalactan, with a small amount of t-β-D-Manp present as a side chain. Hypolipidemic activity assay showed that SRF-3 had good antioxidant and hypolipidemic effects in vitro, suggesting that SRF-3 have potential application in reducing liver fat accumulation.

A simple, rapid, sensitive and eco-friendly LC-MS/MS method for simultaneous determination of free cordycepin and isocordycepin in 10 different kinds of Cordyceps

A simple, rapid, sensitive and eco-friendly liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of free cordycepin (3′-deoxyadenosine) and isocordycepin (2′-deoxyadenosine) in 10 kinds of Cordyceps samples. The samples were prepared by ultrasonic extraction at 75 °C for 30 min with boiling water as the extraction solvent. The LC separation was performed on an Agilent poroshell 120 SB-Aq C18 column (3.0 × 50 mm, 2.7 μm) in isocratic mode with an eco-friendly mobile phase (2% ethanol containing 0.2% acetic acid) at a flow rate of 0.6 mL min−1, and detected by MS/MS in positive mode with multiple reaction monitoring (MRM). The developed method showed good linearity (r > 0.9990), sensitivity (LODs = 0.04 pg, LOQ = 0.1 pg), precision (RSD ≤ 3.8%) and stability (RSD ≤ 3.6%). The recoveries of developed method were 94.4–109.5% (RSD ≤ 5.5%). Compared with reported methods, the current method was rapid (less than 35% analytical time), sensitive (more than 5 folds), and eco-friendly (less than 10 μL harmful organic solvent). 10 different kinds of Cordyceps samples (40 batches) were tested by the developed method. Codycepin was only found in Cordyceps millitaris and C. millitaris fruiting body, and isocordycepin was detected in Cordyceps sinensis and other 6 Cordyceps samples. The developed method would be an improved method for the quality evaluation of Cordyceps samples.

Current perspectives on naturally occurring saponins as anticancer agents

Saponins, a heterogeneous group of sterol and triterpene glycosides, are distributed widely in nature. Naturally occurring saponins could act on diverse targets in cancer cells and consequently exert potential antiproliferative effects in various cancers, including drug-resistant forms. Therefore, naturally occurring saponins are useful templates for the discovery of novel anticancer candidates. Covering articles published between January 2020 and October 2021, this review aims to outline the recent development of naturally occurring steroidal and triterpenoidal saponins with anticancer potential to provide novel anticancer lead hits/candidates.