Applied Biochemistry and Biotechnology

, Volume 184, Issue 4, pp 1061–1072 | Cite as

Highly Efficient Deacidification of High-Acid Rice Bran Oil Using Methanol as a Novel Acyl Acceptor

  • Daoming Li
  • Muniba Faiza
  • Shahid Ali
  • Weifei Wang
  • Chin Ping Tan
  • Bo Yang
  • Yonghua Wang


A highly efficient process for reducing the fatty acid (FA) content of high-acid rice bran oil (RBO) was developed by immobilized partial glycerides-selective lipase SMG1-F278N-catalyzed esterification/transesterification using methanol as a novel acyl acceptor. Molecular docking simulation indicated that methanol was much closer to the catalytic serine (Ser-171) compared with ethanol and glycerol, which might be one of the reasons for its high efficiency in the deacidification of high-acid RBO. Additionally, the reaction parameters were optimized to minimize the FA content of high-acid RBO. Under the optimal conditions (substrate molar ratio of methanol to FAs of 1.8:1, enzyme loading of 40 U/g, and at 30 °C), FA content decreased from 25.14 to 0.03% after 6 h of reaction. Immobilized SMG1-F278N exhibited excellent methanol tolerance and retained almost 100% of its initial activity after being used for ten batches. After purification by molecular distillation, the final product contained 97.86% triacylglycerol, 2.10% diacylglycerol, and 0.04% FA. The acid value of the final product was 0.09 mg KOH/g, which reached the grade one standard of edible oil. Overall, methanol was a superior acyl acceptor for the deacidification of high-acid RBO and the high reusability of immobilized SMG1-F278N indicates an economically attractive process.


Deacidification High-acid rice bran oil Methanol Molecular docking Partial glycerides-selective lipase 



This work was supported by the National Natural Science Foundation of China (21376098) and the Science and Technology Planning Project of Guangdong Province (2014B020204003, 2015B020231006, 2015TX01N207).

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.


  1. 1.
    Mezouari, S., Eichner, K., Kochhar, S. P., Brühl, L., & Schwarz, K. (2006). Effect of the full refining process on rice bran oil composition and its heat stability. European Journal of Lipid Science and Technology, 108, 193–199.CrossRefGoogle Scholar
  2. 2.
    Ghosh, M. (2007). Review on recent trends in rice bran oil processing. Journal of the American Oil Chemists’ Society, 84, 315–324.CrossRefGoogle Scholar
  3. 3.
    Nicolosi, R. J., Austrian, L. M., & Hegsted, D. M. (1991). Rice bran oil lowers serum total and low density lipoprotein cholesterol and apo B levels in nonhuman primates. Atherosclerosis, 88, 133–142.CrossRefGoogle Scholar
  4. 4.
    Wilson, T. A., Nicolosi, R. J., Woolfery, B., & Kritchevsky, D. (2007). Rice bran oil and oryzanol reduce plasma lipid and lipoprotein cholesterol concentrations and aortic cholesterol ester accumulation to a greater extent than ferulic acid in hypercholesterolemic hamsters. The Journal of Nutritional Biochemistry, 18, 105–112.CrossRefGoogle Scholar
  5. 5.
    Chou, T. W., Ma, C. Y., Cheng, H. H., Chen, Y. Y., & Lai, M. H. (2009). A rice bran oil diet improves lipid abnormalities and suppress hyperinsulinemic responses in rats with streptozotocin/nicotinamide-induced type 2 diabetes. Journal of Clinical Biochemistry and Nutrition, 45, 29–36.CrossRefGoogle Scholar
  6. 6.
    Shih, C. K., Ho, C. J., Li, S. C., Yang, S. H., Hou, W. C., & Cheng, H. H. (2011). Preventive effects of rice bran oil on 1,2-dimethylhydrazine/dextran sodium sulphate-induced colon carcinogenesis in rats. Food Chemistry, 126, 562–567.CrossRefGoogle Scholar
  7. 7.
    Zigoneanu, I. G., Williams, L., Xu, Z., & Sabliov, C. M. (2008). Determination of antioxidant components in rice bran oil extracted by microwave-assisted method. Bioresource Technology, 99, 4910–4918.CrossRefGoogle Scholar
  8. 8.
    Aryusuk, K., Puengtham, J., Lilitchan, S., Jeyashoke, N., & Krisnangkura, K. (2008). Effects of crude rice bran oil components on alkali-refining loss. Journal of the American Oil Chemists’ Society, 85, 475–479.CrossRefGoogle Scholar
  9. 9.
    Wang, X. S., Lu, J. Y., Liu, H., Jin, Q. Z., & Wang, X. G. (2016). Improved deacidification of high-acid rice bran oil by enzymatic esterification with phytosterol. Process Biochemistry, 51, 1496–1502.CrossRefGoogle Scholar
  10. 10.
    Jin, J., Xie, D., Chen, H. Q., Wang, X. S., Jin, Q. Z., & Wang, X. G. (2016). Production of rice bran oil with light color and high oryzanol content by multi-stage molecular distillation. Journal of the American Oil Chemists’ Society, 93, 145–153.CrossRefGoogle Scholar
  11. 11.
    Rodrigues, C. E. C., Gonçalves, C. B., Marcon, E. C., Batista, E. A. C., & Meirelles, A. J. A. (2014). Deacidification of rice bran oil by liquid–liquid extraction using a renewable solvent. Separation and Purification Technology, 132, 84–92.CrossRefGoogle Scholar
  12. 12.
    Song, Z. H., Liu, Y. F., Jin, Q. Z., Li, L., Wang, X. G., Huang, J. H., & Liu, R. J. (2012). Lipase-catalyzed preparation of diacylglycerol-enriched oil from high-acid rice bran oil in solvent-free system. Applied Biochemistry and Biotechnology, 168, 364–374.CrossRefGoogle Scholar
  13. 13.
    Wang, X. S., Wang, X. G., & Wang, T. (2017). An effective method for reducing free fatty acid content of high-acid rice bran oil by enzymatic amidation. Journal of Industrial and Engineering Chemistry, 48, 119–124.CrossRefGoogle Scholar
  14. 14.
    Li, D. M., Wang, W. F., Durrani, R., Li, X. X., Yang, B., & Wang, Y. H. (2016). Simplified enzymatic upgrading of high-acid rice bran oil using ethanol as a novel acyl acceptor. Journal of Agricultural and Food Chemistry, 64, 6730–6737.CrossRefGoogle Scholar
  15. 15.
    Li, D. M., Liu, P. Z., Wang, W. F., Wang, X. M., Yang, B., & Wang, Y. H. (2017). An innovative deacidification approach for producing partial glycerides-free rice bran oil. Food and Bioprocess Technology, 10, 1154–1161.CrossRefGoogle Scholar
  16. 16.
    Rao, P. V., Jayaraman, K., & Lakshmanan, C. M. (1992). Lipase catalyzed deacidification of high free fatty acid rice bran oil. Biotechnology Techniques, 6, 169–172.CrossRefGoogle Scholar
  17. 17.
    Zheng, M. M., Zhu, J. X., Huang, F. H., Xiang, X., Shi, J., Deng, Q. C., Ma, F. L., & Feng, Y. Q. (2015). Enzymatic deacidification of the rice bran oil and simultaneous preparation of phytosterol esters-enriched functional oil catalyzed by immobilized lipase arrays. RSC Advances, 5, 70073–70079.CrossRefGoogle Scholar
  18. 18.
    Xu, T. T., Liu, L., Hou, S. L., Xu, J. X., Yang, B., Wang, Y. H., & Liu, J. S. (2012). Crystal structure of a mono- and diacylglycerol lipase from Malassezia globosa reveals a novel lid conformation and insights into the substrate specificity. Journal of Structural Biology, 178, 363–369.CrossRefGoogle Scholar
  19. 19.
    Li, X. X., Li, D. M., Wang, W. F., Durrani, R., Yang, B., & Wang, Y. H. (2016). Immobilization of SMG1-F278N lipase onto a novel epoxy resin: characterization and its application in synthesis of partial glycerides. Journal of Molecular Catalysis B: Enzymatic, 133, 154–160.CrossRefGoogle Scholar
  20. 20.
    Bradford, M. M. (1976). A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical Biochemistry, 72, 248–254.CrossRefGoogle Scholar
  21. 21.
    Wang, W. F., Li, T., Qin, X. L., Ning, Z. X., Yang, B., & Wang, Y. H. (2012). Production of lipase SMG1 and its application in synthesizing diacylglycerol. Journal of Molecular Catalysis B: Enzymatic, 77, 87–91.CrossRefGoogle Scholar
  22. 22.
    Trott, O., & Olson, A. J. (2010). AutoDock Vina: improving the speed and accuracy of docking with a new scoring function, efficient optimization, and multithreading. Journal of Computational Chemistry, 31, 455–461.Google Scholar
  23. 23.
    Kuo, S. J., & Parkin, K. L. (1996). Solvent polarity influences product selectivity of lipase-mediated esterification reactions in microaqueous media. Journal of the American Oil Chemists’ Society, 73, 1427–1433.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2017

Authors and Affiliations

  • Daoming Li
    • 1
  • Muniba Faiza
    • 1
  • Shahid Ali
    • 1
  • Weifei Wang
    • 2
  • Chin Ping Tan
    • 3
  • Bo Yang
    • 4
  • Yonghua Wang
    • 1
  1. 1.School of Food Science and EngineeringSouth China University of TechnologyGuangzhouChina
  2. 2.School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhouChina
  3. 3.Department of Food Technology, Faculty of Food Science and TechnologyUniversiti Putra MalaysiaSerdangMalaysia
  4. 4.School of Bioscience and BioengineeringSouth China University of TechnologyGuangzhouChina

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