IRNAYULI SITEPU, Ph.D.
FACULTY OF BIOTECHNOLOGY 

Irnayuli Sitepu, Ph.D. was born in Bogor, Indonesia. Dr. Sitepu earned her masters degree from Adelaide University, Australia; and doctoral degree from Hokkaido University, Japan, in the field of plant-microbe interactions.
Right before joining i3L, Dr. Sitepu was a postdoctoral scholar at Phaff Yeast Culture Collection, University of California Davis, USA where her main focus was screening yeasts for biodiesel and other oleochemical productions. She was fortunate to have direct access to over 8,000 yeast strains in the collection and enjoyed tapping this treasure for bioprospective studies, such as oleaginous yeast for biodiesel, surfactant, carotenoid pigment; and high protein yeast for pet food using high throughput microbial screening methods (molecular and phenotype based screens).
From 1995 – 2014, Dr. Sitepu worked as Research Microbiologist, FORDA, the Ministry of Forestry, Indonesia.
Dr. Sitepu brought with her to i3L, her experience working in academic and government agency scientific research settings in Indonesia, USA, Australia and Japan.

CURRENT RESEARCH PROJECT AT i3L

  • USAID PEER Cycle 4 (2015 – 2018): Developing a bioeconomy in Indonesia:
    Identification of novel microorganisms and microbial enzymes from Indonesian peatland and buffaloes to improve bioconversion of palm oil residues. Collaboration between i3L and UC Davis, USA.

Selected Past Research Project Involvements

  • 2008-2014: National Institute of Health (NIH)-International Cooperative Biodiversity Groups: “Biodiversity Surveys in Indonesia and Discovery of Health and Energy Solutions”, UC Davis, http://icbg.ucdavis.edu/
  • 2014-2015: Sloan Grants in the Microbiology of the Built Environment Program: “To examine the seasonal nature of the built environment microbiota in wine- and cheese-making facilities”, UC Davis.
  • 2015-2016: Stair (Support translational science and innovative research) Grants, UC Davis: “Structure and activities of biosurfactants produced through a renewable, yeast-based, reduced cost process”, UC Davis.

Selected Peer-Reviewed Publications

  • Boundy-Mills, K., Hess, M., Bennett, A.R., Ryan, M., Kang, S., Nobles, D., Eisen, J.A., Inderbitzin, P., Sitepu, I.R., Torok, T. 2015. The United States Culture Collection Network (USCCN): Enhancing Microbial Genomics Research through Living Microbe Culture Collections. Applied and Environmental Microbiology, AEM. 01176-15.
  • Sitepu, I., Shi, S., Simmons, B., Singer, S., Boundy-Mills, K.L.; Simmons, C. 2014. Yeast tolerance to the ionic liquid 1-ethyl-3-methylimidazolium acetate. FEMS Yeast Research 14, 1286-1294.  DOI: 10.1111/1567-1364.12224.
  • Sitepu IR, Garay, L.A., Sestric, R., Levin, D., Block, D. E., German, J.B., Boundy-Mills, K.L. 2014. Oleaginous yeasts for biodiesel: Current and future trends in biology and production. Biotechnology advances 32, 1336-1360.
  • Sitepu IR, Jin M, Fernandez JE, da Costa Sousa L, Balan V and Boundy-Mills KL. 2014 Identification of oleaginous yeast strains able to accumulate high intracellular lipids when cultivated in alkaline pretreated corn stover. Applied Microbiology and Biotechnology 98, 7645-7657.
  • Sitepu, IR, T. Selby, T. Lin, S. Zhu, and K. Boundy-Mills. 2014. Carbon source utilization and inhibitor tolerance of 45 oleaginous yeast species. J Industrial Microbioology and Biotechnology., 1-10.

SitepuI.R.  Sestric, R.,  Ignatia, L., Levin, D.,  German, J.B., Gillies, L.A.,  Almada, L.A.G., Boundy-Mills, K. L.2013. Manipulation of culture conditions alters lipid content and fatty acid profiles of a wide variety of known and new oleaginous yeasts speciesBioresource Technology 144:36.-369. http://dx.doi.org/10.1016/j.biortech.2013.06.047.

  • Sitepu, I.R., Ignatia, L., Franz, A.K., Wong, D.M., Faulina, S.A., Tsui, M., Kanti, A.,  Boundy-Mills, K. 2012. An improved high-throughput Nile red fluorescence assay for estimating intracellular lipids in a variety of yeast species. J. Microbiol. Methods., 91(2): 321-328.

You can find more information on Dr. Sitepu in this link : http://irnayulisitepu.myfreesites.net/

Published Papers

  • Luis A Garay, Irnayuli R Sitepu, Tomas Cajka, Jian Xu, Hui Ean Teh, J Bruce German, Zhongli Pan, Stephanie R Dungan, David E Block, Kyria L Boundy-Mills. Extracellular fungal polyol lipids: A new class of potential high value lipids. 2018. Biotechnology Advances.
  • Irnayuli R Sitepu, Luis A Garay, Lauren Enriquez, Russell Fry, John H Butler, Julian M Lopez, Atit Kanti, Sarah A Faulina, Agustinus J Nugroho, Blake A Simmons, Steven W Singer, Christopher W Simmons, Kyria Boundy-Mills. 2017. 1-Ethyl-3-methylimidazolium tolerance and intracellular lipid accumulation of 38 oleaginous yeast species. Applied microbiology and biotechnology 101 (23-24), 8621-8631.
  • Luis A Garay, Irnayuli R Sitepu, Tomas Cajka, Erin Cathcart, Oliver Fiehn, J Bruce German, David E Block, Kyria L Boundy-Mills. 2017. Simultaneous production of intracellular triacylglycerols and extracellular polyol esters of fatty acids by Rhodotorula babjevae and Rhodotorula Paludigena. Journal of industrial microbiology & biotechnology 44 (10), 1397-1413.
  • Garay, L.A., Sitepu I.R., Cajka, T., Fiehn, O., Cathcart, E., Fry, R.W., Kanti, A., Nugroho, A.J., Faulina, S.A., Stephanandra, S.,  German, J.B.,  Boundy-Mills K.   Discovery of synthesis and secretion of polyol esters of fatty acids by four basidiomycetous yeast species in the order Sporidiobolales. Industrial Microbiolology and Biotechnology. doi:10.1007/s10295-017-1919-y
  • Cajka, T., Garay, L.A., Sitepu I.R., Boundy-Mills K., and Fiehn, O. 2016. Multiplatform Mass Spectrometry-Based Approach Identifies Extracellular Glycolipids of the Yeast Rhodotorula babjevae UCDFST 04-877. Journal of Natural Products. DOI: 10.1021/acs.jnatprod.6b00497.
  • Garay, L.A., Sitepu I.R., Chandra, I., Shi, S., Lin,T., German, J.B. and Boundy-Mills, K.L. 2016.  Eighteen new oleaginous yeast species. Journal of Industrial Microbiology and Biotechnology, 1-14. doi:10.1007/s10295-016-1765-3. Matan Shelomi, Sitepu, I.R., Boundy-Mills, K.L. and Kimsey, L.S.. 2015. Review of the Gross Anatomy and Microbiology of the Phasmatodea Digestive Tract. Journal of Orthoptera Research 24 (1), 29-40.
  • Boundy-Mills, K., Hess, M., Bennett, A.R., Ryan, M., Kang, S., Nobles, D., Eisen, J.A., Inderbitzin, P., Sitepu, I.R., Torok, T. 2015. The United States Culture Collection Network (USCCN): Enhancing Microbial Genomics Research through Living Microbe Culture Collections. Applied and Environmental Microbiology, AEM. 01176-15.
  • Sitepu, I.R., Shi, S., Simmons, B., Singer, S., Boundy-Mills, K.L.; Simmons, C. 2014. Yeast tolerance to the ionic liquid 1-ethyl-3-methylimidazolium acetate. FEMS Yeast Research 14, 1286-1294. DOI: 10.1111/1567-1364.12224.
  • Sitepu, I.R., Garay, L.A., Sestric, R., Levin, D., Block, D. E., German, J.B., Boundy-Mills, K.L. 2014. Oleaginous yeasts for biodiesel: Current and future trends in biology and production. Biotechnology advances 32, 1336-1360.
  • Sitepu, I.R., Jin M, Fernandez JE, da Costa Sousa L, Balan V and Boundy-Mills KL. 2014 Identification of oleaginous yeast strains able to accumulate high intracellular lipids when cultivated in alkaline pretreated corn stover. Applied Microbiology and Biotechnology 98, 7645-7657.
  • Sitepu, I.R., Selby, T. Lin, S. Zhu, and K. Boundy-Mills. 2014. Carbon source utilization and inhibitor tolerance of 45 oleaginous yeast species. J Industrial Microbioology and Biotechnology., 1-10.
  • Lei Wang, Wataru Hisano, Yuta Murai, Munenori Sakurai, Yasuyuki Muto, Haruka Ikemoto, Masashi Okamoto, Takashi Murotani, Reika Isoda, Dongyeop Kim, Yasuko Sakihama, Irnayuli R. Sitepu, Yasuyuki Hashidoko, Yasumaru Hatanaka, Makoto Hashimoto. 2013. Distinct Metabolites for Photoreactive L-Phenylalanine Derivatives in Klebsiella CK6 Isolated from Rhizosphere of a Wild Dipterocarp Sapling. Molecules, 18, 8393-8401; doi:10.3390/molecules18078393
  • Kim, Rahman, A., Sitepu, I.R., Hashidoko, Y. 2013. Accelerated Degradation of Exogenous Indole by Burkholderia unamae Strain CK43B Exposed to Pyrogallol-Type Polyphenols. Bioscience, Biotechnology, and Biochemistry, 77 (8), 1722-1727. DOI http://dx.doi.org/10.1271/bbb.130282 JOI DN/JST.JSTAGE/bbb/130282
  • R. Sitepu, Sestric, R., Ignatia, L., Levin, D.,  German, J.B., Gillies, L.A.,  Almada, L.A.G., Boundy-Mills, K. L.2013. Manipulation of culture conditions alters lipid content and fatty acid profiles of a wide variety of known and new oleaginous yeasts species. Bioresource Technology 144:36.-369. http://dx.doi.org/10.1016/j.biortech.2013.06.047.
  • Kim, Sitepu, I.R., Hashidoko, Y. 2013. Induction of biofilm formation in Burkholderia unamae CK43B of β-Proteobacteria exposed to exogenous indole and gallic acid. Applied and Environmental Microbiology. doi: 10.1128/AEM.01209-13
  • Sitepu, I.R., Ignatia, L., Franz, A.K., Wong, D.M., Faulina, S.A., Tsui, M., Kanti, A., Boundy-Mills, K. 2012. An improved high-throughput Nile red fluorescence assay for estimating intracellular lipids in a variety of yeast species. Microbiol. Methods., 91(2): 321-328.
  • Rahman, A., Sitepu, I.R., Tang, S., Hashidoko, Y. 2010. Salkowski’s Reagent Test as a Primary Screening Index for Functionalities fo Rhizobacteria Isolated from Wild Dipterocarp Saplings Growing Naturally on Medium-Strongly Acidic Tropical Peat Soil. Bioscience Biotechnology and Biochemistry, 74(11): 2202-2208.
  • Sitepu, I.R., Aryanto, Hashidoko, Y., Turjaman, M. 2010. Application of phytohormone-producing rhizobacteria to improve the growth of Aquilaria seedlings in the nursery (in Indonesian language with English abstract). Info Hutan, VII(2): 107-116.
  • Sitepu, I.R., Hashidoko, Y., Santoso, E., Tahara, S. 2009. Growth promoting properties of bacteria isolated from dipterocarp plants of acidic lowland tropical peat forest in Central Kalimantan, Indonesia. Journal of Forestry Researc, 6: 96 – 118.
  • Sitepu, I.R., Hashidoko, Y., Aryanto, Turjaman, M., Tahara, S., Miftahuliyah, S.S., Santoso, E. 2008. Studies on functional bacteria of Indonesian tropical forest plants for biorehabilitation of degraded lands. Journal of Forestry Research, 5 (1): 2008: 21 – 35.
  • Turjaman, M., Tamai, Y., Sitepu, I.R., Santoso, E., Osaki, M., Tawaraya, K. 2008. Improvement of early growth of two tropical peat-swamp forest tree species Ploiarium alternifolium and Calophyllum hosei by two arbuscular mycorrhizal fungi under greenhouse conditions. New Forests, 36: 1-12.
  • Sitepu, I.R., Aryanto, Ogita, N., Osaki, M., Santoso, E., Tahara, S, Hashidoko, Y.,  Screening of rhizobacteria from dipterocarp seedlings and saplings for the promotion of early growth of Shorea selanica seedlings. Tropics, 16: 245-252.
  • Barry, K.M., Irianto, R.S.B., Santoso, E., Turjaman, M., Widyati, E., Sitepu, I.R., Mohammed, C.L., 2004. Incidence of heartrot in harvest-age Acacia mangium in Indonesia, using a rapid survey method. Forest Ecology and Management 190, 273-280.
  • Suharti M., Sitepu I.R. and Anggraeni I. 2000. Behaviour, intensity and effect of stem borer attack, Indarbela acutistriata on Paraserianthes falcataria plantation forest in Kediri Forest District.  Forest Research Bulletin 623: 37 – 50. (in Indonesian language with English abstract)
  • Suharti M., Sitepu I.R., Darwiati W. and Anggraeni I. 2000. Efficacy of some biological, floral and chemical control agents on bagworm pests. Forest Research Bulletin 624: 11-28. (in Indonesian language)

 

ISSN Proceedings

  • Sitepu, R., Hashidoko, Y., Santoso, E, Tahara, S. 2007. Potent phosphate-solubilizing bacteria isolated from dipterocarps grown in peat swamp forest in Central Kalimantan and their possible utilization for biorehabilitation of degraded peatland. International Symposium and Workshop on Tropical Peatland “Carbon-Climate-Human Interactions – Carbon Pools, Fire, Mitigation, Restoration and Wise Use”, Yogyakarta, Indonesia, 27-31 August 2007.
  • Sitepu, I.R., Santoso, E., Tahara, S., Turjaman, M., Osaki, M., Hashidoko, Y. 2004. Proposed approach for peatland rehabilitation using enriched bacterial-inoculated seedling: Case studies on dipterocarps.  Proceedings of International Workshop on Human Dimension of tropical Peatland under Global environmental Changes, Bogor, 8 – 9 December 2004
  • Sitepu I.R. and Suharti M. 1998. Pest and disease management in Industrial Forest Plantations in Indonesia.  Workshop Proceedings of Sustained Productivity of Short and Medium Rotation Plantation Forests for Commercial and Community Benefit in Indonesia. An Analysis of Research Priorities, Bogor, Indonesia.  CSIRO Forestry and Forest Products: 39-48
  • Suharti M., Sitepu I.R. and Anggraeni I. 1998. Biological control measures of Xystrocera festiva using Beauveria bassiana Proceedings of Expose on Follow Up of Research Results: The Role of Forest in Fulfilling Human Demands and Anticipation of Global Issues, 24-25 November 1997 Bogor, Indonesia: 82-90. (in Indonesian language with English abstract)
  • Sitepu I.R. and Wibowo A. 1997. Pests of Industrial Forest Plantations: Alternatives to synthetical insecticides control measure. Proceedings of Workshop on Constraints and Strategies of Pest Management in Plantation Forest Area, 17-19 June 1997, Bandungan, Indonesia. (in Indonesian language with English abstract)
  • Suharti M., Asmaliyah, Anggraeni I. and Sitepu I.R. Prospect of Beauveria bassiana fungi as biological control agent of Paraserianthes falcataria stem borer. Proceedings of Workshop on Constraints and Strategies of Pest Management in Plantation Forest Area, 17-19 June 1997, Bandungan, Indonesia. (in Indonesian language with English abstract)
  • Anggraeni I., Asmaliyah, Sitepu I.R. and Suharti M. 1996. Prospect of biological control measure of pests and diseases of Industrial Forest Plantations. Proceedings of Research Result Discussion in Promoting the Utilization of Sustainable Forest, May 1996, Bogor, Indonesia: 95-105. (in Indonesian language with English abstract)