Antiviral pentacyclic triterpenoids isolated from Sanguisorba officinalis roots against viral hemorrhagic septicemia virus and simultaneous quantification by LC-MS/MS

Viral hemorrhagic septicemia (VHS) leads to significant economic losses for the flounder aquaculture in Korea. It is caused by viral hemorrhagic septicemia virus (VHSV), a negative sense ssRNA virus in the family Rhabdoviridae [1]. We have previously shown that an 80% methanolic extract of Sanguisorba officinalis L. (Rosaceae) roots and its methylene chloride fraction (SOMC) had significant activities against VHSV in FHM cells and in olive flounder Paralichthys olivaceus [2]. Here, we investigated antiviral compounds and simultaneously quantified from SOMC using LC-ESI-triple quadrupole mass spectrometry. Further isolations for SOMC yielded seven known pentacyclic triterpenoids, 3β,19α-dihydroxyurs-12-en-28-oic acid (or pomolic acid) (1), 3-O-α-L-arabinopyranosylpomolic acid β-D-glucopyranosyl ester (or ziyuglycoside I) (2), 3-oxopomolic acid (3), 3,11-dioxopomolic acid (4), 2-hydroxypomolic acid (5), 28-O-β-D-glucopyranosylpomolic acid ester (6) and 3-O-α-L-arabinopyranosylpomolic acid (or ziyuglycoside II) (7) [3]. Compound 1 and 5 showed no antiviral activity, while 3 and 4 with 3-oxo or 11-oxo group showed the highest antiviral activities with EC₅₀ values between 5 – 10µM comparable to that of ribavirin, the positive control. Compound 2 and 7 also showed some anti-VHSV activity with EC₅₀ values of 20 – 40µM. The average contents of the most abundant 2 and the most active 3 in SOMC were determined as 20.97 and 1.83%, respectively. Standard curves showed good linearity (r ²= 0.9999) within the test range. The established method showed good precision, accuracy and specificity with intra- and inter-day variations of < 3% and recoveries of 102.85 – 104.67%. These results suggested that Sanguisorba officinalis L. roots, SOMC and its pentacyclic triterpenoids can be promising antiviral agents against VHS.

Acknowledgements: This research was supported partly by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (NRF-2012R1A1A3014130 and NRF-2015R1C1A2A01053487).

Keywords: Sanguisorba officinalis, viral hemorrhagic septicemia virus, antiviral, triterpenoids, LC-MS/MS.

References:

[1] Skall HF, Olesen NJ, Mellergaard S. Viral haemorrhagic septicaemia virus in marine fish and its implications for fish farming – a review. J Fish Dis 2005; 28: 509 – 529

[2] Seo JK, Do CY, Jung MH, Jung SJ, Kang SY. In vivo antiviral activity of Sanguisorba officinalis roots against viral hemorrhagic septicaemia virus in olive flounder Paralichthys olivaceus. Planta Med 2015; 16: PW 45.

[3] Cheng DI, Cao XP. Pomolic acid derivatives from the root of Sanguisorba officinalis. Phytochemistry 1992; 31: 1317 – 1320

No conflict of interest has been declared by the author(s).