Nutritional Characterization and Untargeted Metabolomics of Oyster Mushroom Produced Using Astragalus membranaceus var. mongolicus Stems and Leaves as Substrates

Abstract

Astragalus membranaceus var. mongolicus (AMM) is an edible and medicinal material and is commonly used in East Asia. According to the pharmacopeia of China, the dried root of AMM is medicinal. However, the aerial parts of AMM are always directly discarded after harvest. The stems and leaves are also rich in active compounds, including saponins, flavonoids, terpenoids, and polysaccharides. To rationally use resources, waste products from AMM stems and leaves are useful substrates for edible fungus cultivation. Here, oyster mushroom (Pleurotus ostreatus var. florida) was cultivated on a basal substrate supplemented with AMM stems and leaves (AMM group). The nutritional and chemical composition of the fruiting body were analyzed by metabolomics and chemometrics. Our results showed that AMM addition to the substrate affected the fresh weight, moisture, fat, protein, and element concentrations, and amino acid composition of oyster mushroom. Moreover, 2,156 metabolites were detected and annotated based on the metabolomics data, of which 680 were identified as differentially expressed metabolites. Many active phytometabolites previously identified in AMM herbs were also detected in the metabolomics of oyster mushroom from AMM group, including 46 terpenoids, 21 flavonoids, 17 alkaloids, 14 phenylpropanoids, and 3 fatty acids. In summary, our results imply that oyster mushroom cultured with AMM stems and leaves might have very high nutritional therapy health care value.

Utilization of functional agro-waste residues for oyster mushroom production: Nutritions and active ingredients in healthcare

“…Our previous study reported similar findings ( Zeng et al., 2022b ). In the case of C. pilosula , the content of lobetyolin in the agro-waste residues (dried stems and leave) were 0.142 ± 0.011 mg/g (0.0142%).…”

“…Referring to the method recorded in previous studies ( Ma et al., 2021 ; Zeng et al., 2022b ), six biological replicates of mushrooms from CSL and control group were assayed for sample extraction and metabolomics analysis. In brief, 50 mg of each sample was extracted with a methanol buffer with internal standard (0.4 mL 80% aqueous, and 20 μL 0.3 mg/mL 2-chloro-D-phenylalanine) for 30 min in an ultrasonic bath.…”

“…Lobetyolin is a standard composition to evaluate the quality of Radix Codonopsis. According to the Chinese Pharmacopoeia (2020) and the previous studies (Dong et al, 2021;Zeng et al, 2022b), lobetyolin in oyster mushrooms from CSL and control group was extracted by the ultrasound-assisted method. In brief, 10 g of each dried samples was precisely weighed and introduced into a conical flask with 50 mL of methanol.…”

“…The species of the genus Pleurotus occupy the third position in the production of edible mushrooms ( Fernandes et al., 2015 ). Based on the data from China edible fungi association, the total yield of oyster mushrooms in 2019 reached 300,000 tons ( Zeng et al., 2022b ). Compared to other edible fungi, oyster mushrooms have shown several advantages in cultivation, including short growth cycle, few environmental controls, disease and pest resistance, and low producing cost ( Wan-Mahari et al., 2020 ).…”

Structural Characterization and Immunobiological Activity of Polysaccharides from Astragalus Oyster Mushroom

“…It is used as medicine and food in the improvement of health and treatment of various disease [16]. Various scientific literatures show that the supplementation of the mushroom-growing substrates with herbs have simultaneous edible and medicinal value, such as Astragalus and Codonopsis pilosula enhancing the nutritional value of edible fungi [14,17,18]. Hengshan Astragalus (also known as "Zheng Bei Qi", meaning Astragalus of geo-authentic origin), which is produced on Hengshan Mountain, Hunyuan County, Shanxi Province, is a widely used traditional Chinese herb and nutraceutical [19].…”