Giving a conclusion about hypoglycemia activity of Catharanthus roseus in Vietnam

• Two Catharanthus roseus samples are collected in Hoai Nhon, Binh Dinh and Tu Liem, Ha Noi.
• The n-hexane-, dichloromethane-, ethyl acetate- and methanol- extracts were prepared from ground powder of Catharanthus roseus.
• The all extracts of the sample collected in Hoai Nhon, Binh Dinh were tested on anti-α-glucosidase activity. The result showed that dichloromethane- and ethyl acetate-extracts possess good activity with IC₅₀ of 4.0 and 9.18 µg/mL, respectively.
• From the active extracts (dichloromethane, ethyl acetate) 9 compounds were isolated and structural elucidated. They are spatozoate (33), kaurenoic acid (34), ursonic acid (35), 3-hydroxy-11-ursen-28,13-olide (36), vindoline (37), ursolic acid (38), β-sitosterol (39), stigmasterol (40), β-sitosterol glucoside (41). Among them, compounds 33, 35 and 36 were found for the first time from this species.
• The yield of ursolic acid, the main constituent of Catharanthus roseus, collected in Hoai Nhon, Binh Dinh and Tu Liem, Ha Noi was determined as 0.69 and 0.97%, respectively.
• The result of anti-glucosidase activity test of some isolated compounds indicated that compounds 35, 36 and 38 have good activity, better than acarbose, especially ursolic acid (38) with IC₅₀ of 3.83 µg/mL.
• Compounds 33-36 were tested for cytotoxicity on 9 human cancer cell lines: liver cancer (Hep-G2), mouth cancer (KB), lung cancer (LU-1), breast cancer (MCF-7), melanoma cancer (SK-Mel2), acute leukemia (HL60), ovarian cancer (SW626), prostate cancer (LNCaP) and colon cancer (HT-29). Among them, 35 was found to be the most active one against all tested cancer cell lines with the IC₅₀ values ranged from 4.36 to 30.15 mg/mL. Compound 34 showed moderate activity against all tested cancer cell lines with the IC50 values ranged from 49.07 to 70.30 mg/mL.
• The antidiabetic effect of ursolic acid was investigated on diabetic mice induced by tail vein injection with alloxan. The result showed that ursolic acid with dose of 200 and 300 mg/kgP/day reduced 45.75% and 51.31% serum glucose levels in diabetic mice compared with control sample, statistically significant (p<0.05).
• Ursolic acid revealed no acute toxicity at the concentration of 2500, 5000 and 7500 mg/kgP/day, because LD₅₀ values were not determined at studied concentrations.

• This is the first study on hypoglycemia activity of Catharanthus roseus in Vietnam.
• The dichlometane and etyl acetate extracts of Catharanthus roseus collected in Hoai Nhon, Binh Dinh showed strong anti α-glucosidase enzym activity with IC₅₀ values of 4.0 and 9.18 µg/mL, respectively.
• From the active extracts, nine compounds were isolated and structural elucidated as spatozoate (33), kaurenoic acid (34), ursonic acid (35), 3-hydroxy-11-ursen-28,13-olide (36), vindoline (37), ursolic acid (38), β-sitosterol (39), stigmasterol (40), β-sitosterol glucoside (41). Among them, compounds 33, 35 and 36 were found for the first time in this species.
• The anti α-glucosidase enzym activity results of compounds 33-35 isolated from Catharanthus roseus are reported for first time. Compound 35 showed good activity with IC₅₀ of 45.92 µg/mL.
• The studied results indicated that, ursolic acid is the main hypoglycemia component of Catharanthus roseus in Vietnam.

Scientific papers in referred journals (list): 

• 01 international publication:
• 01 national publication: Nguyen Thanh Tam, Dao Duc Thien, and Tran Van Sung. Further chemical constituents of Catharanthus rosues (L.) G. Don collected from Binh Dinh province, Vietnam. Vietnam Journal of Chemistry, 52(5), 626-628 (2014).

Patents (list): 01 Utility Solution (valid applications accepted); Nguyen Thanh Tam, Tran Van Sung, Dao Duc Thien, Nguyen Thi Hoang Anh, Trinh Thi Thuy. Extraction and purification procedure of ursolic acid, the main hypoglycemia component from Catharnthus roseus.

Other products (if applicable): Education a Master student: Tran Thi Tinh “Study on isolation, structure determination and hypoglycemia activity of some components isolated from Catharnthus roseus in Vietnam”.