Adenosine Deaminase Inhibitory Activity of Medicinal Plants: Boost the Production of Cordycepin in Cordyceps militaris.

Cordycepin, also known as 3'-deoxyadenosine, is a major active ingredient of Cordyceps militaris with diverse pharmacological effects. Due to its limited supply, many attempts have been conducted to enhance the cordycepin content. As part of this study, eight medicinal plants were supplemented with cultivation substrates of Cordyceps to increase the cordycepin content. Cordyceps cultivated on brown rice supplemented with Mori Folium, Curcumae Rhizoma, Saururi Herba, and Angelicae Gigantis Radix exhibited increased cordycepin content compared to a brown rice control. Among them, the addition of 25% Mori Folium increased the cordycepin content up to 4 times. Adenosine deaminase (ADA) modulates the deamination of adenosine and deoxyadenosine, and the inhibitors have therapeutic potential with anti-proliferative and anti-inflammatory properties. As ADA is also known to be involved in converting cordycepin to 3'-deoxyinosine, the inhibitory activity of medicinal plants on ADA was measured by spectrophotometric analysis using cordycepin as a substrate. As expected, Mori Folium, Curcumae Rhizoma, Saururi Herba, and Angelicae Gigas Radix strongly inhibited ADA activity. Molecular docking analysis also showed the correlation between ADA and the major components of these medicinal plants. Conclusively, our research suggests a new strategy of using medicinal plants to enhance cordycepin production in C. militaris.

Characterization of α-glucosidase inhibitory constituents of the fruiting body of lion's mane mushroom (Hericium erinaceus).

ETHNOPHARMACOLOGICAL RELEVANCE: Hericium erinaceus, commonly called lion's mane mushroom, is an edible and medicinal mushroom that has been traditionally used for the treatment of metabolic disorders, gastrointestinal diseases and memory impairment. In this study, potential anti-hyperglycemic constituents were identified to support the traditional usage of H. erinaceus. MATERIALS AND METHODS: The components of H. erinaceus were purified using various column chromatography techniques. The structure of the separated compounds was determined based on spectroscopic data analysis, i.e., 1D and 2D NMR analysis. The anti-hyperglycemic activity of the isolated compounds was evaluated by measuring the inhibitory effects on α-glucosidase activity. Molecular docking analysis was also conducted for elucidation of α-glucosidase inhibitory activity of isolated compounds. RESULTS: Ten compounds including four new compounds, erinacenols A-D (1-4), were isolated from the fruiting bodies of H. erinaceus. Investigation of the anti-hyperglycemic effect of isolated compounds demonstrated that erinacenol D (4), 4-[3',7'-dimethyl-2',6'-octadienyl]-2-formyl-3-hydroxy-5-methyoxybenzylalcohol (6), hericene A (7), hericene D (8) and hericenone D (9) strongly inhibited α-glucosidase activity with IC50 values of <20 µM. The structure activity relationship suggested the importance of long side chain for α-glucosidase inhibitory activity. Further analysis by molecular docking demonstrated the interaction of α-glucosidase and isolated compounds, which supported the inhibitory activity of α-glucosidase. CONCLUSION: Our present study demonstrated the beneficial effect of H. erinaceus by characterization of α-glucosidase inhibitory compounds, including four new compounds. This approach can be valuable support for the traditional use of H. erinaceus for the treatment of diabetes and metabolic diseases, which needs to be clarified by further in-vivo study.

Phenylpropanoid-Conjugated Triterpenoids from the Leaves of Actinidia arguta and Their Inhibitory Activity on α-Glucosidase.

Actinidia arguta, commonly called hardy kiwifruit or kiwiberry, has cold-resistant properties and can be cultivated in Asia, including Korea. Seven new triterpenoids (2-4 and 8-11) along with eight known triterpenoids were isolated from the leaves of A. arguta through various chromatographic techniques. The new triterpenoids were defined as actiniargupenes A-C (2-4), actinidic acid derivatives with phenylpropanoid constituent units, dehydroisoactinidic acid (8), and actiniargupenes D-F (9-11), asiatic acid derivatives with phenylpropanoid substituents, on the basis of 1D and 2D NMR and MS data. Among the triterpenoids, those with a phenylpropanoid constituent unit showed inhibitory activity on α-glucosidase, which suggested the importance of the phenylpropanoid moiety. Molecular docking analysis demonstrated the interaction between the 4'-OH group of the phenylpropanoid moiety and α-glucosidase.