Research Units

Laboratory of Metal Bioleaching

Laboratory of Metal Bioleaching was founded in 1961. The main scientific fields of the laboratory are: microbiology, metal biotechnology, ecology, bioremediation

RESEARCH MAIN DIRECTIONS

• Ecology of metal leaching chemolithotrophic bacteria
• Biodiversity
• Physiology, biochemistry, geochemical activity
• Bioleaching of metals from primary and secondary mineral resources
• Development of biohydrometallurgical technologies    

MAIN INVESTIGATION RESULTS

• Biodiversity of iron- and sulfur-oxidizing bacteria in natural and technogenic biotopes (mineral wastewaters, tailings) in sulfide ores of different geoformations in Armenia was studied.
• New genera and species of sulfur- and iron-oxidizing bacteria Leptospirillum ferroxidans (Markosyan, 1972), Thiobacillus acidophilus  (Acidiphilium acidophilum)  (Markosyan, 1972), Acidithiobacillus tandzuti (Vardanyan, Vardanyan, 2016), Sulfobacillus thermosulfidooxidans subsp. asporogenes (Vardanyan et al., 1988; Vardanyan et al., 2015) have been isolated in the Laboratory for the first time.
• The role of isolated bacteria in bioextraction of metals from different sulfide minerals was revealed.
• Peculiarities of biofilm formation by isolated bacteria and its contribution to metal bioleaching were studied.
• Based on the use of thermophilic bacteria and their consortia new methods for enhancing the efficiency of non-ferrous and valuable metal extraction were developed.
• A rich collection of acidophilic microorganisms valuable not only for fundamental, but also for applied research has been created. The Collection is included in the Microbial Depository Center (MDC) and their nucleotide sequences are included in the World Gene Database (GenBank).

Investigations carried out in the Laboratory were performed in the framework of International Inco-COPERNICUS-2, CRDF, MES-BMBF-2012grants, as well as grants funded by the RA State Budget. The main results of the research carried out were summarized in doctoral and PhD theses and in scientific papers and presented at international conferences in Switzerland (FEMS 2011), China (IBS 2011), Chile (IBS 2013), UK (Biohydrometallurgy’14),  Romania (2016), Poland (2016), Germany (IBS 2017), Serbia (2019) and Japan (IBS 2019).

MAIN OBJECTIVES AND TASKS

• Study of biodiversity and ecology of chemolithotrophic iron-  and sulfur-oxidizing bacteria
• Screening and development of  highly active adapted bacteria and their consortia
• Use of bacteria and their consortia for the recovery of valuable metals from non-conditioning ores, dumps and tailings
• Development of effective biohydrometallurgical technologies for extraction of metals
• Recycling and bioremediation of natural and technogenic wastes 

COLLABORATION

1. Cyprus University of Technology, Department of Environmental Science and Technology (Limassol, Cyprus)
2. University of Liege, Mineral Processing and Recycling Unit (Liege, Belgium)
3. Martin Luther University Halle-Wittenberg (Halle, Germany)
4. Yerevan State University, Faculty of Biology, Department of Microbiology, Biochemistry and Biotechnology

LIST OF GRANT PROJECTS

1. ANSEF 2020 Grant microbio-2227 “Bio-based technology for recovery of value-added metals from secondary raw materials” (Project Manager: A. Vardanyan)
2. Wallonie-Bruxelles International (WBl) Excellence Grant 2020 - “BioMetals: Recovery of value-added metals from secondary raw materials“  for Postdoctoral Research in University of Liege (ULg)(Project Manager: A. Vardanyan)
3. Fundação Calouste Gulbenkian (Calouste Gulbenkian Foundation) Short Term Conference and Travel Grants program for IBS 2019 Conference held on 20-23 October, 2019, Fukuoka, Japan (Grantee: A. Vardanyan, PhD).
4. FEMS Meeting Organizer Grant (ID#: FEMS-GO-2018-194) to organize the International Conference Microbes: Biology & Application 2019 with the support of Armenian Microbiological Association (AMA) held on 9-11 October, 2019 (Grantee: A. Vardanyan, PhD).
5. FEMS Research Grant (ID#: FEMS-GO-2018-136) for “Innovative microbiological methods for risks characterization of sites contaminated by metals” project with MLU Halle-Wittenberg, Faculty of Natural Sciences, Halle, Germany, 2019 Feb. 3 - Apr. 16 (Grantee: A. Khachatryan).
6. FEMS Meeting Organizer Grant (ID#: FEMS-GO-2018-098) to organize the 1^st Scientific School “Extremophiles: Windows to the future...” with the support of Armenian Microbiological Association, 24-26 October, 2018 (Grantee: A. Vardanyan, PhD).
7. FEMS Research Grant (ID#: FEMS-RG-2016-0104) for “Increasing efficiency of mesophilic bacteria during bioleaching of metals from secondary resources” project with University of Liege, Mineral Processing and Recycling Unit (Liege, Belgium), 2017 Apr. - 2017 June (Grantee: A. Vardanyan, PhD).
8. Travel Grant of the Council of Young Scientists of the National Academy of Sciences of Armenia, 2016 (Grantee: A. Vardanyan, PhD).
9. FEMS Travel Grant-2016 (ID# FEMS-MAG-2016-0080) for ICCE-2016 conference in Iasi, Romania on November 9-11, 2016 (Grantee: A. Vardanyan, PhD).
10. FEMS Research Grant (ID#: FEMS-RG-2015-0046) for “Enhance copper bioleaching of low copper ore by adding constructed microbial consortium” project with Cyprus University of Technology, Department of Environmental Science and Technology (Limassol, Cyprus), 2015 Nov. - 2016 Feb. (Grantee: A. Vardanyan, PhD).
11. Grant of financial support to acquire scientific equipments and/or materials of the Council of Young Scientists of the National Academy of Sciences of Armenia, 2015 (Grantee: A. Vardanyan, PhD).
12. Fundação Calouste Gulbenkian (Calouste Gulbenkian Foundation) Short Term Conference and Travel Grants program for participation in Biohydrometallurgy’14 Conference in Falmouth, UK held on 7-9 June, 2014 (Grantee: A. Vardanyan, PhD).
13. Travel Grant for Young Scientists, 2014 (Grantee: A. Vardanyan, PhD).
14. SCS-BMBF-2012 Prօject No. 12GE-005 “Isolation and characterization of novel metal leaching microorganisms and perspectives of intensification of biohydrometallurgical processes” (Project Manager: N. Vardanyan,  DSc).

KEY PUBLICATIONS 

Scientific articles

1. D. I. Stom, O. N. Matveeva, G. O. Zhdanova, O. N. Ponamoreva, A. B. Kupchinsky, M. Yu. Tolstoy, N. S. Vardanyan, M. N. Saksonov, A. N. Chesnokova, Li Wang, and S. J. Ge. Transformation of oil and hexadecane in soil by microbial preparations and earthworms. Bioremediation Journal, 2021, p.1-10. https://doi.org/10.1080/10889868.2020.1860894
2. D. I. Stom, G. O. Zhdanova, O. B. Kalashnikova, A. G. Bulaev, A. V. Kashevskii, A. B. Kupchinsky, N. S., Vardanyan, O. N. Ponamoreva, S. V. Alferov, M. N. Saksonov, A. N. Chesnokova, and M. Yu. Tolstoy. Acidophilic Microorganisms Leptospirillum sp., Acidithiobacillus sp., Ferroplasma sp. As a Cathodic Bioagents in a MFC. Geomicrobiology Journal, 2021 December, p.1-7. https://doi.org/10.1080/01490451.2020.1856980
3. Khachatryan A.S, Melkonyan Z.S., Aabrahamyan N. M., Vardanyan N.S. Biohydrometallurgical processing of low-grade copper-molybdenum ore. / Biol. J. Armenia, 3 (72), p.29-36. 2020. ISSN 0366-5119
4. Arevik Vardanyan and Ioannis Vyrides, Effect of Organics to acidophilic bioleaching microorganisms in various process (sludge, solvent extraction) and strategies to alleviate. Minerals Engineering, 2019, 143, https://doi.org/10.1016/j.mineng.2019.105943
5. Khachatryan, A. C. (2019) Influence of Fe 2+ and Fe 3+ on the growth of Leptospirillum ferriphilum CC and oxidation of Fe 2+ . Biolog Journal of Armenia, 71 (3). Pp. 83-88. 
6. Vardanyan Narine, Badalyan Hamlet, Markosyan Levon Vardanyan Arevik, Zhang Ruiyong, Sand Wolfgang. Newly Isolated Acidithiobacillus sp. Ksh from Kashen Copper Ore: Peculiarities of EPS and Colloidal Exopolysaccharide. // Frontiers in Microbiology (Front. Microbiol.), 2020, Vol.11, p.1-11. https://doi.org/10.3389/fmicb.2020.01802
7. Arevik Vardanyan, Narine Vardanyan, Anna Khachatryan, Ruiyong Zhang, Wolfgang Sand Adhesion to Mineral Surfaces by Cells of Leptospirillum, Acidithiobacillus and Sulfobacillus from Armenian Sulfide Ores // Minerals, 2019, 9(2), 69, pp. 1-13. https://doi.org/10.3390/min9020069
8. Levon Markosyan, Hamlet Badalyan, Narine Vardanyan, Arevik Vardanyan Study of colloidal polysaccharides produced by iron  oxidizing bacteria  Leptospirillum ferriphilum CC // Geomicrobiology J., 2019, v. 36, No. 2, pp. 188-193. https://doi.org/10.1080/01490451.2018.1534903
9. Vardanyan N, Sevoyan G, Navasardyan T, Vardanyan A. Recovery of valuable metals from polymetallic mine tailings by natural microbial consortium // Environmental  technology, 2019, vol. 40, No. 26, pp. 3467–3472.   https://doi.org/10.1080/09593330.2018.1478454
10. Narine S. Vardanyan and Arevik K. Vardanyan Thermophilic Chemolithotrophic Bacteria in Mining Sites (Chapter 7) // Extremophiles in Eurasian Ecosystems: Ecology, Diversity, and Applications. Eds. Dilfuza Egamberdieva, Nils-Kеre Birkeland, Hovik Panosyan, Wen-Jun Li. Springer, 2018, pp. 187- 218.  https://doi.org/10.1007/978-981-13-0329-6
11. Arevik Vardanyan, Narine Vardanyan, Anna Khachatryan, Zaruhi Melkonyan Chemical oxidation integrated into bioleaching of pyrite and chalcopyrite using immobilized biomass // Environment Engineering and Management Journal, 2018, vol.17, No. 4, pp. 897- 904. http://eemj.eu/index.php/EEMJ/article/view/3554
12. Arevik Vardanyana, Nasia Kafab, Viktoras Konstantinidisc, Seung Gu Shind, Ioannis Vyrides Phosphorus dissolution from dewatered anaerobic sludge: Effect of pHs, microorganisms, and sequential extraction // Bioresource Technology, 2018, 249,  pp. 464–472. 74. https://doi.org/10.1016/j.biortech.2017.09.188    
13. Khachatryan A.S, Vardanyan N.S. Metal resistance in chalcopyrite bioleaching bacteria // Journal of Environmental Science, Computer Science and Engineering & Technology (JECET), 2017, Sec. A, Vol. 6, No. 4, pp. 540-547. [DOI: 10.24214/jecet.A.6.4.54047.].
14. N.S.Vardanyan, G.G. Sevoyan, A.K. Vardanyan Bioleaching of tailings resulting from benefication of polymetallic ores for recovery of valuable metals // Solid State Phenomena, vol. 262, pp. 113-117, 2017. doi:10.4028/www.scientific.net/SSP.262.113.
15. Khachatryan A.S, Vardanyan N.S. Metal resistance in chalcopyrite bioleaching bacteria // Journal of Environmental Science, Computer Science and Engineering & Technology (JECET), September 2017-November 2017, Sec. A, 6, 4, pp. 540-547. [DOI: 10.24214/jecet.A.6.4.54047.].
16. Arevik Vardanyan, Panagiotis Achilleos, Nasia Kafa, Maria Papadopoulou, Narine Vardanyan, Ioannis Vyrides Effect of Cell Lysis (CLs) products on acidophilic chemolithotrophic microorganisms and role of Acidocella species // Geomicrobiology, Journal, 2017, 34, 10, pp. 916-922.  DOI: http://dx.doi.org/10.1080/01490451.2017.1300203
17. Vardanyan A.K., Vardanyan N.S. Bioleaching of pyrite and chalcopyrite by new isolated thermotolerate sulfur-oxidizing bacteria Acidithiobacillus tandzuti sp.nov. // International Journal of Scientific & Engineering Research, 2016, 7, 7, pp. 203-207. https://doi.org/10.14299/ijser.2016.07.001
18. Vardanyan A., Stepanyan S., Vardanyan N., Markosyan L., Sand W., Vera V., Zhang R. Study and assessment of microbial communities in natural and commercial bioleaching systems // Minerals Engineering, 2015, 81, pp. 167-172. http://dx.doi.org/10.1016/j.mineng.2015.05.001
19. Vardanyan A.K., Vardanyan N.S., Markosyan L.M. Peculiarities of adhesion and bioleaching of pyrite by new isolated Leptospirillum spp. bacteria // Universal Journal of Microbiology Research, 2013, 1(2), pp. 22-25.
20. Vardanyan A.K., Markosyan L.S., Vardanyan N.S. Immobilization of new isolated iron oxidizing bacteria on natural carriers // Advanced Materials Research, 2013, 825, pp. 388-391.
21. Варданян Н. С., Варданян А.К. // Прикл. биохимия и микробиология, 2011, 47, 5, стр. 566-571.

Abstracts Presented at Conferences

1. Ioana Popescu, Daniel Cristea, Arevik Vardanyan, Narine Vardanyan. Silver nanoparticles’ synthesis mediated by alpha-amylase. //Book of abstracts "New Trends on Sensing- Monitoring- Telediagnosis for Life Sciences", NT SMT-LS 2020, Online, July 3-4, 2020, Romania Belgrade, Serbia, Association of Metallurgical Engineers of Serbia (AMES), 2020, P.119.http://www.healthfoodenviron.unitbv.ro/2020/NT-SMT-LS-2020-Book-of-Abstracts.pdf
2. Vardanyan A., Vardanyan N. Leptospirillum ferriphilum strain as an efficient oxidizer of pyrite and chalcopyrite /Electronic abstract book “FEMS 2020 Online Conference of Microbiology”, October, 28 – 31, 2020, Belgrade, Serbia. Session 7, Enviromnental Microbiology, p.367. https://fems2020belgrade.com/ Presentation
3. Narine Vardanyan, Anna Khachatryan, Zaruhi Melkonyan, Nelly Abrahamyan, Arevik Vardanyan. Processing of low-grade copper-molybdenum ores by indigenous mirobial cultures. // Electronic abstract Book “FEMS 2020 Online Conference of Microbiology”, October, 28 – 31, 2020, Belgrade, Serbia. Session 7, Enviromnental Microbiology, p.5. https://fems2020belgrade.com/ Presentation
4. Arevik Vardanyan, Narine Vardanyan, Stoyan Gaydardzhiev Bioleaching of metals from e-waste using immobilized biomass of mesophilic Acidithiobacillus ferrooxidans // Proc. International Symposium on Biohydrometallurgy (IBS 2019), 20-23 October, 2019, Fukuoka, Japan, p. 207.
5. Khachatryan A.S., Vardanyan N.S., Melkonyan Z.S., Vardanyan A.K. The influence of metal ions on ferrous ion oxidation kinetics by Letospirillum ferriphilum // Proc. International Symposium on Biohydrometallurgy (IBS 2019), 20-23 October, 2019, Fukuoka, Japan, p.166.
6. Khachatryan A., Vardanyan N. Tolerance of isolated metal leaching bacteria to Mo⁶⁺ // Book of Abstracts of International Conference “Microbes: Biology & Application”, October 9-11, 2019, Yerevan, Armenia, pp. 37-38.
7. Khachatryan A., Melkonyan Z., Vardanyan A., Vardanyan N. Biohydrometallurgical processing of Kajaran low-grade copper-molybdenum ores // Book of Abstracts of International Conference “Microbes: Biology & Application”,
8. Vardanyan A.K., Vardanyan N.S., Khachatryan A.S., Melkonyan Z.S.  Bioleaching of pyrite by mixed cultures of iron and/or sulphur oxidizing bacteria isolated in Armenia // Metallurgical & Materials Engineering Congress of South-East Europe (MME-SEE 15) June 5-7, 2019, Belgrade, Serbia. (Poster Presentation)
9. Khachatryan A., Vardanyan N., Melqonyan Z., Vardanyan A. Study of resistance of isolated Leptospirillum ferriphilum CC and Acidithiobacillus sp. 13Zn // Book of Abstracts of International Scientific Conference of Young Researches “Biotechnology: Science and Practice” September 28-30, 2017, Yerevan, Armenia, p. 20.
10. Vardanyan N., Sevoyan G., Vardanyan A., Melqonyan Z., Khachatryan A. The prevalence and biodiversity of microorganisms relevant to AMD generation in metallurgical wastes and tailings // Book of Abstracts of International Scientific Conference of Young Researches “Biotechnology: Science and Practice” September 28-30, 2017, Yerevan, Armenia, p. 7.
11. N.S. Vardanyan, G.G. Sevoyan, A.K. Vardanyan Bioleaching of tailings resulting from benefication of polymetallic ores for recovery of valuable metals // Proceedings of the 22^nd International Biohydrometallurgy Symposium (IBS2017), 2017, pp. 113-117.
12. Варданян Н.С., Хачатрян А.С., Варданян А.К., Мелконян З.С. // Международная научно-практическая конференция “Микробное биоразнообразие: актуальные проблемы и решения”, посвященная 25-летию независимости республики Казахстан, 25 ноября 2016, Астана, стр. 64-67.
13. Варданян Н.С., Хачатрян А.С., Варданян А.К., Мелконян З.С. // Международная научно-практическая конференция “Микробное биоразнообразие: актуальные проблемы и решения”, посвященная 25-летию независимости республики Казахстан, 25 ноября 2016, Астана, стр. 136- 140.
14. A.K. Vardanyan, N.S. Vardanyan, A.S. Khachatryan, Z.S. Melkonyan Chemical oxidation integrated into bioleaching of pyrite and chalcopyrite using immobilized biomass // 3^rd International Conference on Chemical Engineering - ICCE, 2016, November 9-11, 2016, Iaşi, România.
15. Варданян Н.С., Варданян А.К. Хачатрян А.С. // Материалы 5-ого Всероссийского Симпозиума с международным участием “Автотрофные микрорганизмы” -  М., МАКС Пресс, 2015, стр. 87.
16. Vardanyan A., Vardanyan N. Bioleaching of pyrite by pure and mixed culture of chemolithothrophic bacteria // IX Meeting of the Mineralogical Society of Poland “Contemporary Challenges in the Mineralogical Sciences” held in Sandomierz, Poland, 8-11 October, 2015, Mineralogia - Special papers, Vol. 44, pp. 105-106.
17. Stepanyan S., Vardanyan N. Biooxidation of chalcopyrite by new isolated Acidithiobacillus sp. 13Zn with mixed cultures // IX Meeting of the Mineralogical Society of Poland “Contemporary Challenges in the Mineralogical Sciences” held in Sandomierz, Poland, 8-11 October, 2015, Mineralogia - Special papers, Vol. 44, pp. 97-98.
18. Vardanyan A., Vardanyan N., Markosyan L. Immobilization of chemolithotrophic bacteria for enhancing efficiency of bioleaching // Proc. of International Youth Conference “Science and Innovation-2015”, September, 25-27, 2015, Tsaghkadzor, Armenia, pp. 251-257.
19. Vardanyan A.K., Vardanyan N.S., Markosyan L.S. Extracellular polimeric substances  (EPS) and biofilm formation by iron oxidizing bacteria // Book of Abstracts of the 3^rd International Scientific Conference on “Diologues on Sciences”, June 23-26, 2015, Yerevan, Armenia, p. 31.
20. Vardanyan A.K., Vardanyan N.S. Isolation and identification of metal bioleaching iron oxidizing bacteria // Book of Abstracts of the 3^rd International Scientific Conference on “Diologues on Sciences”, June 23-26, 2015, Yerevan, Armenia, p. 30. (Poster Presentation)
21. Stepanyan S., Vardanyan N. Biooxidation of pyrite sulfide ore and copper concentrate by new isolated sulfur and/or iron oxidizing bacteria // Youth International Conference “Innovation Approaches in Science”, Tsaghkadzor, Armenia, December 5-7, 2014, p. 73- 77.
22. Stepanyan S., Vardanyan N. Biooxidation of pyrite by sulfur and / or iron oxidizing bacteria and their communities // Intern. Scientific Workshop “Trends in Microbiology and Microbial Biotechnology”, October 5-8, 2014, Yerevan, Armenia. p. 92.
23. Vardanyan A.K., Khachatryan A.M., Stepanyan S.Kh., Vardanyan N.S. Activity of immobilized cells of Leptospirillum ferriphilum and Sulfobacillus thermosulfidooxidans on natural carriers // 5^th Congress of European Microbiologists (FEMS), 21-25, July, 2013, Leipzig, Germany, A/255.
24. Vardanyan A.K. Immobilization of New Isolated Bacteria  Leptospirillum spp. on Natural Supporters  // Book of Abstracts of  the 2^nd International Scientific Conference of Young Researchers “Contribution of the Young Generation in the Development of Biotechnology” Dedicated to the 70^th anniversary of NAS of Armenia, October 1-4, 2013, Yerevan, p. 75.