Nanopowders of Centella asiatica (L.) were produced using planetary ball mill in order to investigate the differences of water extraction yield of asiatic acid as compared to micropowders of Centella asiatica. Effect of extraction time (20–60？min) on extraction yield of asiatic acid from Centella asiatica was examined. Results showed that water extraction of asiatic acid using Centella asiatica nanopowders exhibits was almost 50% higher extraction yield with 7.09？mg/g as compared to the micropowders of Centella asiatica. It was concluded that nanopowders contributed in enhancing water extraction yield of asiatic acid as compared to micropowders. Thereby utilizing nanopowders in water extraction could improve the extraction of asiatic acid via clean, eco-friendly, and less expensive process. 1. Introduction Centella asiatica (L.) is one of the medicinal plants that has been declared to have a variety of medicinal effects. Its bioactive compounds include asiatic acid, asiaticoside, madecassic acid, and madecassoside. Asiaticoside (Figure 1(a)) is the principal bioactive ingredient among them since asiaticoside gave a better effect on antibacterial and fungicidal activity against bacteria and fungi [1]. Asiatic acid (Figure 1(b)) also displays good biological effects such as promoting collagen synthesis stimulating extracellular matrix accumulation, and promoting fibroblast proliferation in a rat wound model [2]. Figure 1: Chemical structure of (a) asiaticoside and (b) asiatic acid. Asiatic acid is an aglycone form of asiaticoside and easily formed by hydrolyzing the sugar moiety of asiaticoside structure in acid condition. Therefore, some data suggest that the therapeutic effect of asiaticoside may come from asiatic acid [3]. Some studies show the significance of sugar moiety in the structure of asiaticoside which may enhance the bioavailability of asiatic acid compared to the only aglycone structure alone [4]. But once again, enriching asiatic acid in the extract is important since all the synthesizing alkyl groups require hydrolyzing of asiaticoside first prior modification of asiatic acid functional groups [4]. By modification, the asiatic acid may provide us with data in relationship between structural and hepatoprotetive properties in order to develop new novel drugs for treating disease [5, 6]. Extraction of active chemical compounds from natural sources is a most important research area in pharmaceutical and chemical industry. Bioactive compound extraction aims to get a better extraction yield and less time consuming without altering the structure
References
[1]
B. M. Hausen, “Centella asiatica (Indian pennywort), an effective therapeutic but a weak sensitizer,” Contact Dermatitis, vol. 29, no. 4, pp. 175–179, 1993.
[2]
F. X. Maquart, G. Bellon, P. Gillery, Y. Wegrowski, and J. P. Borel, “Stimulation of collagen synthesis in fibroblast cultures by a triterpene extracted from Centella asiatica,” Connective Tissue Research, vol. 24, no. 2, pp. 107–120, 1990.
[3]
W. R. Rush, G. R. Murray, and D. J. M. Graham, “The comparative steady-state bioavailability of the active ingredients of Madecassol,” European Journal of Drug Metabolism and Pharmacokinetics, vol. 18, no. 4, pp. 323–326, 1993.
[4]
P.-J. Shim, J.-H. Park, M.-S. Chang et al., “Asiaticoside mimetics as wound healing agent,” Bioorganic and Medicinal Chemistry Letters, vol. 6, no. 24, pp. 2937–2940, 1996.
[5]
B.-S. Jeong, C. K. Young, and E.-S. Lee, “Modification of C2,3,23,28 functional groups on asiatic acid and evaluation of hepatoprotective effects,” Bulletin of the Korean Chemical Society, vol. 28, no. 6, pp. 977–982, 2007.
[6]
B.-S. Jeong, K. L. Mi, C. K. Young, and E.-S. Lee, “Modification of C2 functional group on asiatic acid and the evaluation of hepatoprotective effects,” Archives of Pharmacal Research, vol. 30, no. 3, pp. 282–289, 2007.
[7]
E. S. Ong, J. S. H. Cheong, and D. Goh, “Pressurized hot water extraction of bioactive or marker compounds in botanicals and medicinal plant materials,” Journal of Chromatography A, vol. 1112, no. 1-2, pp. 92–102, 2006.
[8]
W.-J. Kim, J. Kim, B. Veriansyah et al., “Extraction of bioactive components from Centella asiatica using subcritical water,” Journal of Supercritical Fluids, vol. 48, no. 3, pp. 211–216, 2009.
[9]
R. Konwarh, S. Pramanik, D. Kalita, C. L. Mahanta, and N. Karak, “Ultrasonication—a complementary “green chemistry” tool to biocatalysis: a laboratory-scale study of lycopene extraction,” Ultrasonics Sonochemistry, vol. 19, no. 2, pp. 292–299, 2012.
[10]
S. R. Shirsath, S. H. Sonawane, and P. R. Gogate, “Intensification of extraction of natural products using ultrasonic irradiations—a review of current status,” Chemical Engineering and Processing, vol. 53, pp. 10–23, 2012.
[11]
P. Y. Ma, Z. Y. Fu, Y. L. Su et al., “Modification of physicochemical and medicinal characterization of Liuwei Dihuang particles by ultrafine grinding,” Powder Technology, vol. 191, no. 1-2, pp. 194–199, 2009.
[12]
Y. L. Su, Z. Y. Fu, C. J. Quan, and W. M. Wang, “Fabrication of nano Rhizama Chuanxiong particles and determination of tetramethylpyrazine,” Transactions of Nonferrous Metals Society of China, vol. 16, pp. S393–S397, 2006.
[13]
S. Huang and W. H. Chang, “Advantages of nanotechnology-based Chinese herb drugs on biological activities,” Current Drug Metabolism, vol. 10, no. 8, pp. 905–913, 2009.
[14]
Dynamic Light Scattering: An Introduction in 30 Minutes, Malvern Instruments, Malvern, Wis, USA, 2005.
[15]
P. Ma, Z. Fu, Y. Su, and J. Ma, “Nano pulverization of traditional Chinese medicine Liuwei Dihuang,” Journal Wuhan University of Technology, vol. 21, no. 2, pp. 105–108, 2006.
[16]
R. Rajkhowa, L. Wang, J. Kanwar, and X. Wang, “Fabrication of ultrafine powder from eri silk through attritor and jet milling,” Powder Technology, vol. 191, no. 1-2, pp. 155–163, 2009.
[17]
W. Abdelwahed, G. Degobert, S. Stainmesse, and H. Fessi, “Freeze-drying of nanoparticles: formulation, process and storage considerations,” Advanced Drug Delivery Reviews, vol. 58, no. 15, pp. 1688–1713, 2006.
[18]
N. R. Barbosa, F. Pittella, and W. F. Gattaz, “Centella asiatica water extract inhibits iPLA2 and cPLA2 activities in rat cerebellum,” Phytomedicine, vol. 15, no. 10, pp. 896–900, 2008.
[19]
M. C. Kwon, W. Y. Choi, Y. C. Seo et al., “Enhancement of the skin-protective activities of Centella asiatica L. urban by a nano-encapsulation process,” Journal of Biotechnology, vol. 157, no. 1, pp. 100–106, 2012.
[20]
A. Soumyanath, Y.-P. Zhong, E. Henson et al., “Centella asiatica extract improves behavioral deficits in a mouse model of Alzheimer's disease: investigation of a possible mechanism of action,” International Journal of Alzheimer's Disease, vol. 2012, Article ID 381974, 9 pages, 2012.
[21]
T. J. Mason, L. Paniwnyk, and J. P. Lorimer, “The uses of ultrasound in food technology,” Ultrasonics Sonochemistry, vol. 3, no. 3, pp. S253–S260, 1996.
[22]
S. Zhao, K.-C. Kwok, and H. Liang, “Investigation on ultrasound assisted extraction of saikosaponins from Radix Bupleuri,” Separation and Purification Technology, vol. 55, no. 3, pp. 307–312, 2007.
[23]
J. Dong, Y. Liu, Z. Liang, and W. Wang, “Investigation on ultrasound-assisted extraction of salvianolic acid B from Salvia miltiorrhiza root,” Ultrasonics Sonochemistry, vol. 17, no. 1, pp. 61–65, 2010.
[24]
M. Vinatoru, “An overview of the ultrasonically assisted extraction of bioactive principles from herbs,” Ultrasonics Sonochemistry, vol. 8, no. 3, pp. 303–313, 2001.
[25]
L. Paniwnyk, H. Cai, S. Albu, T. J. Mason, and R. Cole, “The enhancement and scale up of the extraction of anti-oxidants from Rosmarinus officinalis using ultrasound,” Ultrasonics Sonochemistry, vol. 16, no. 2, pp. 287–292, 2009.
[26]
B. Burlando, L. Verotta, L. Cornara, and E. Bottini-Massa, Herbal Principles in Cosmetics: Properties and Mechanisms of Action, Taylor & Francis Group, 2010.
[27]
C. K. Kokate, A. P. Purohit, and S. B. Gokhale, Pharmacognosy, NIRALI PRAKASHAN, 2009.
[28]
D. Monti, A. Candido, M. M. Cruz Silva, V. K？en, S. Riva, and B. Danieli, “Biocatalyzed generation of molecular diversity: selective modification of the saponin asiaticoside,” Advanced Synthesis and Catalysis, vol. 347, no. 7-8, pp. 1168–1174, 2005.
[29]
T. W. G. Solomons and C. B. Fryhle, Organic Chemistry, John Wiley & Sons, 9th edition, 2008.
[30]
H. Wang, C. Zhang, H. He, and L. Wang, “Glucose production from hydrolysis of cellulose over a novel silica catalyst under hydrothermal conditions,” Journal of Environmental Sciences, vol. 24, no. 3, pp. 473–478, 2012.
[31]
K. D. O. Vigier and F. Jér？me, Heterogeneously-Catalyzed Conversion of Carbohydrates, vol. 295, 2010.
