Isosteviol

Isosteviol is a diterpenoid that has been found in P. tetraspermum and has diverse biological activities.^1,2,3,4 It is also a hydrolysis product of the natural non-caloric sweetener stevioside (Item No. 11902).² Isosteviol scavenges hydroxyl and superoxide radicals in cell-free assays (IC₅₀s = 76.92 and 91.7 µg/ml, respectively) and inhibits DNA polymerase α, β, and λ, as well as topoisomerase II (IC₅₀s = 64, 177, 103, and 190 µM, respectively).^1,2 It is active against various Gram-positive and Gram-negative bacteria, including several strains of methicillin-resistant S. aureus (MRSA; MICs = 8-250 µg/ml), and fungi, including C. albicans and T. mentagrophytes (MICs = 62.5-500 µg/ml).¹ Isosteviol inhibits the proliferation of MOLT-4 leukemia cells in a concentration-dependent manner.² It induces relaxation of isolated rat aortic strips precontracted with vasopressin, an effect that can be reversed by the potassium channel inhibitors glibenclamide (glyburide; Item No. 15009) or apamin (Item No. 17082) but not charybdotoxin (Item No. 24115).³ Isosteviol (5 and 10 mg/kg) reduces plasma glucose levels in the intravenous glucose tolerance test in Zucker diabetic rats.⁴ It has been used in the synthesis of isosteviol glycosides with anticancer activity.⁵

WARNING This product is not for human or veterinary use.

1. Abdullah Al-Dhabi, N., Valan Arasu, M., and Rejiniemon, T.S. In vitro antibacterial, antifungal, antibiofilm, antioxidant, and anticancer properties of isosteviol Iiolated from endangered medicinal plant Pittosporum tetraspermum. Evid. Based Complement. Alternat. Med. 164261 (2015).

2. Mizushina, Y., Akihisa, T., Ukiya, M., et al. Structural analysis of isosteviol and related compounds as DNA polymerase and DNA topoisomerase inhibitors. Life Sci. 77(17), 2127-2140 (2005).

3. Wong, K.-L., Chan, P., Yang, H.-Y., et al. Isosteviol acts on potassium channels to relax isolated aortic strips of Wistar rat. Life Sci. 74(19), 2379-2387 (2004).

4. Ma, J., Ma, Z., Wang, J., et al. Isosteviol reduces plasma glucose levels in the intravenous glucose tolerance test in Zucker diabetic fatty rats. Diabetes Obes. Metab. 9(4), (2007).

5. Sharipova, R.R., Belenok, M.G., Garifullin, B.F., et al. Synthesis and anti-cancer activities of glycosides and glycoconjugates of diterpenoid isosteviol. MedChemComm 10(8), 1488-1498 (2019).