Fig. 1. Chemical structures of isolated compounds.
Fig. 2. Effects of crude on the viability of HIT-T15 cells.
Fig. 3. Effects of EtOAc soluble fraction on the viability of HIT-T15 cells.
Fig. 5. Effects of (+)-catechin on the viability of HIT-T15 cells.
Fig. 6. Effects of (-)-epicatechin on the viability of HIT-T15 cells.
Fig. 10. Insulin secretion of HIT-T15 treated with the crude.
Fig. 12. Insulin secretion of HIT-T15 treated with the H2O soluble fraction.
Fig. 14. Insulin secretion of HIT-T15 treated with (-)-epicatechin.
Fig. 16. Insulin secretion of HIT-T15 treated with taxifolin-3′-O-β-D-(+)-glucose.
Fig. 11. Insulin secretion of HIT-T15 treated with the EtOAc soluble fraction.
Fig. 13. Insulin secretion of HIT-T15 treated with (+)-catechin.
Fig. 15. Insulin secretion of HIT-T15 treated with taxifolin.
Fig. 17. Insulin secretion of HIT-T15 treated with ρ-coumaric acid.
Fig. 18. Effects of crude on the viability of L6 cells.
Fig. 19. Effects of EtOAc soluble fraction on the viability of L6 cells.
Fig. 20. Effects of H2O soluble fraction on the viability of L6 cells.
Fig. 21. Effects of (+)-catechin on the viability of L6 cells.
Fig. 26. Glucose uptake activities of the crude.
Fig. 28. Glucose uptake activities of the H2O soluble fraction.
Fig. 30. Glucose uptake activities of (-)-epicatechin.
Fig. 32. Glucose uptake activities of taxifolin-3′-O-β-D-(+)-glucose.
Fig. 27. Glucose uptake activities of the EtOAc soluble fraction.
Fig. 29. Glucose uptake activities of (+)-catechin.
Fig. 31. Glucose uptake activities of taxifolin.
Fig. 33. Glucose uptake activities of ρ-coumaric acid.
Fig. 4. Effects of H2O soluble fraction on the viability of HIT -T15 cells.
Fig. 7. Effects of taxifolin on the viability of HIT-T15 cells.
Fig. 8. Effects of taxifolin-3′-O-β-D-(+)-glucose on the viability of HIT-T15 cells.
Fig. 9. Effects of ρ-coumaric acid on the viability of HIT-T15 cells.
Fig. 22. Effects of (-)-epicatechin on the viability of L6 cells.
Fig. 23. Effects of taxifolin on the viability of L6 cells.
Fig. 24. Effects of taxifolin-3′-O-β-D-(+)-glucose on the viability of L6 cells.
Fig. 25. Effects of ρ-coumaric acid on the viability of L6 cells.
Table 1. Weight of each fraction of Korean red pine inner bark extracts
Table 2. Weight of the isolated compounds
References
- Ahn, B.T., Oh, K.J., Park, S.K., Chung, S.G., Cho, E.H. Kim, J.G., Ro J.S., Lee, K.S. 1996. Phenolic compounds from leaves of Spiraea salicifolia. Korean Journal of Pharmacognosy 27(3): 178-183.
- Aviram, M. 2000. Review of human studies on oxidative damage and antioxidant protection related to cardiovascular diseases. Free Radical Research 33: 85-97.
- Choi, Y.Y., Sohn, H.S., Shin, H.T. 2010. Clinical benefit of delf-Monitoring of blood glucose in non-insulin treated patients with type 2 diabetes : A systematic review and meta-analysis. Korean Journal of Clinical Pharmacy 20(3): 189-192.
- Denizot, F., Lang, R. 1986. Rapid colorimetric assay for cell growth and survival: modification of the tetrazolium dye procedure giving improved sensitivity and reliability. Journal of Immunological Methods 89: 271-277. https://doi.org/10.1016/0022-1759(86)90368-6
-
Eizirik, D.L., Mandrup-Poulsen T. 2001. A choice of death-the signal-transduction of immune-mediated
${\beta}$ -cell apoptosis. Diabetologia 44: 2115-2133. https://doi.org/10.1007/s001250100021 - Erben, B., Benjamin, H.S.L. 2000. Pycnogenol inhibits generation of inflammatory mediators in macrophage. Nutrition Research 20: 249-259. https://doi.org/10.1016/S0271-5317(99)00157-8
- Evans, J.L., Goldfine, I.D., Maddux, B.A., Grodsky, G.M. 2002. Oxidative stress and stress-activated signaling pathways: a unifying hypothesis of type 2 diabetes. Endocrine Reviews 23(5): 599-622. https://doi.org/10.1210/er.2001-0039
-
Fabio, V., Kobuchi, H., Lester, P. 1998. Procyanidins extracted from Pinus maritima (Pycnogenol
${(R)}$ ) : Scavengers of free radical species and modulators of nitrogen monoxide metabolism in activated murine RAW 264.7 macrophages. Free Radical Biology and Medicine 24: 1120-1129. https://doi.org/10.1016/S0891-5849(97)00430-9 - Foo, L., Karchesy, J.J. 1989. Procyanidin dimers and trimers from Douglas fir inner bark. Phytochemistry 28(6): 1743-1747. https://doi.org/10.1016/S0031-9422(00)97836-1
- Ham, Y.H., Bae, Y.S. 1995, Flavonoids extractives of Populus albaglandulosa. Journal of the Korean Wood Science and Technology 23(2): 94-99
- Harborne, J.B., Mabry, T.J. 1982. The flavonoid: advances in research, Chapman and Hall Ltd.
- Heo, S.J., Hwang, J.Y., Choi, J.I., Han, J.S., Kim, H.J., Jeon, Y.J. 2009. Diphlorethohydroxycarmalol isolated from Ishige okamurae, a brown algae, a potent alpha-glucosidase and alpha-amylase inhibitor, alleviates postprandial hyperglycemia in diabetic mice. European Journal of Pharmacology 615(1-3): 252-256. https://doi.org/10.1016/j.ejphar.2009.05.017
- Ho, G.T.T., Kase, E.T., Wangensteen, H3., Barsett, H. 2017. Effect of phenolic compounds from elderflowers on glucose- and fatty acid uptake in human myotubes and HepG2-cells. Molecules 22(1): 1-15. https://doi.org/10.3390/molecules22010001
- Jeong, M.J., Yang, J.Y., Choi, W.S., Kim, J.W., Kim, S.J., Park, M.J. 2017. Chemical Compositions and Antioxidant Activities of Essential Oil Extracted from Neolitsea aciculata (Blume) Koidz Leaves. Journal of the Korean Wood Science and Technology 45(1): 96-106. https://doi.org/10.5658/WOOD.2017.45.1.96
- Jung, J.Y., Yang, J.K., Lee, W.H. 2017. Antioxidant and Safety Test of Natural Extract of Quercus mongolica. Journal of the Korean Wood Science and Technology 45(1): 116-125. https://doi.org/10.5658/WOOD.2017.45.1.116
- Kim, B.H., Son, S.M. 2006. Mechanism of developing diabetic vascular complication by oxidative stress. journal of the Korean Endocrine Society 21(6): 448-459. https://doi.org/10.3803/jkes.2006.21.6.448
- Kim, I.H., Ko, Y.J., Choi, I.D., Kim, Y.G., Ryu, C.H., Shin, K.H. 2012. Antioxidative activities of pine needles and quality characteristics of Korean wheat noodle with pine needle powder. Journal of Agriculture & Life Science 46(5): 127-136.
- Kim, J.W., Im, S.B., Jeong, H.R., Jung, Y.S., Lee, I.I., Kim, K.J., Park, S.K., Kim, D.O. 2018. Neuroprotective effects of korean red pine (Pinus densiflora) bark extract and its phenolics. Journal of Microbiology and Biotechnology 28(5): 679-687. https://doi.org/10.4014/jmb.1801.01053
- Kim, S.H., Lee, S.Y., Cho, S.M., Hong, C.Y., Park, S.Y., Park, M.J., Choi, I.G. 2017. Antioxidant activities of cryptomeria japonica leaves extracts by extraction methods. Journal of the Korean Wood Science and Technology 45(5): 495-510. https://doi.org/10.5658/WOOD.2017.45.5.495
- Kim, T.W. 1996. Korean Tree. Kyohak. 28-36.
- Lee, Y.J., Han, O.T., Choi, H.S., Lee, B.Y., Chung. H.J., Lee, O.H. 2013. Antioxidant and antiadipogenic effects of PineXol. Korean Journal of Food Science and Technology 45(1): 97-103. https://doi.org/10.9721/KJFST.2013.45.1.97
-
Liu, X., Wei, J., Tan, F., Zhou, S., Wurthwein, G., Rohdewald, P. 2004. Antidiabetic effec of pycnogenol
${(R)}$ french maritime pine bark extract in patients with diabetes type II. Life Sciences 75: 2505-2513. https://doi.org/10.1016/j.lfs.2003.10.043 -
Miriam, C., Nils, W., Jonas, J.C., Anne, J., Sigurd, L. and Decio, L.E. 2005. Mechanisms of pancreatic
${\beta}$ -cell death in type 1 and type 2 diabetes: many differences, few similarities. Diabetes 54: 97-107. https://doi.org/10.2337/diabetes.54.suppl_2.S97 - Novo, E., Parola, M. 2008. Redox mechanisms in hepatic chronic wound healing and fibrogenesis. Fibrogenesis Tissue Repair 1: 1-58. https://doi.org/10.1186/1755-1536-1-1
- Shinn, S.H., Min, H.J., Bae, Y.S. 2019. Phenolic compounds from japanese anise (Illicium anisatum L.) leaves. Journal of Korean Wood Science and Technology 47(1): 1-7. https://doi.org/10.5658/WOOD.2019.47.1.1
- Standl, E., Schnell, O. 2012. Alpha-glucosidase inhibitors cardiovascular considerations and trial evaluation. Diabetes and Vascular Disease Research 9(3): 163-169. https://doi.org/10.1177/1479164112441524