title: Estimation of antioxidant, antimicrobial activity and brine shrimp toxicity of plants collected from Oymyakon region of the Republic of Sakha (Yakutia), Russia.
abstract: BACKGROUND
  Several plants are reported to be produced various biological active compounds. Lichens from the extreme environments such as high altitude, high UV, drought and cold are believed to be synthesized unique types of secondary metabolites than the other one. Several human pathogenic bacteria and fungi have been muted into drug resistant strains. Various synthetic antioxidant compounds have posed carcinogenic effects. This phenomenon needs further research for new effective drugs of natural origin. This manuscript aimed to screen new source of biological active compounds from plants of subarctic origin.
  
  
  RESULTS
  A total of 114 plant species, including 80 species of higher plants, 19 species of lichens and 15 species of mosses, were collected from Oymyakon region of the Republic of Sakha (Yakutia), Russia (63˚20'N, 141˚42'E-63˚15'N, 142˚27'E). Antimicrobial, DPPH free radical scavenging and brine shrimp (Artemia salina) toxicity of all crude extract were evaluated. The obtained result was analyzed and compared with commercial standards. A total of 28 species of higher plants showed very strong antioxidant activity (DPPH IC50, 0.45-5.0 μg/mL), 13 species showed strong activity (DPPH IC50, 5-10 μg/mL), 22 species showed moderate antioxidant activity (DPPH IC50,10-20 μg/mL) and 17 species showed weak antioxidant activity (DPPH IC50 more than 20 μg/mL). Similarly, 3 species of lichen showed strong antioxidant activity, one species showed moderate and 15 species showed weak DPPH reducing activity. In addition, 4 species of mosses showed moderate antioxidant activity and 11 species showed weak antioxidant activity. Similarly, extracts of 51 species of higher plants showed antimicrobial (AM) activity against Staphylococcus aureus and 2 species showed AM activity against Candida albicans. Similarly, 11 species of lichen showed AM activity against S. aureus and 3 species showed AM activity against Escherichia coli. One species of moss showed AM activity against S. aureus. And finally, one species of higher plant Rheum compactum and one species of lichen Flavocetraria cucullata showed the toxicity against Brine shrimp larvae in 100 μg/mL of concentration.
  
  
  CONCLUSIONS
  The experimental results showed that subarctic plant species could be potential sources of various biologically active natural compounds.
authors.forename: Babita
authors.initials: B
authors.lastname: Paudel
authors.forename: Hari Datta
authors.initials: HD
authors.lastname: Bhattarai
authors.forename: Il Chan
authors.initials: IC
authors.lastname: Kim
authors.forename: Hyoungseok
authors.initials: H
authors.lastname: Lee
authors.forename: Roman
authors.initials: R
authors.lastname: Sofronov
authors.forename: Lena
authors.initials: L
authors.lastname: Ivanova
authors.forename: Lena
authors.initials: L
authors.lastname: Poryadina
authors.forename: Joung Han
authors.initials: JH
authors.lastname: Yim
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000032:analysis / Q000494:pharmacology*; D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology*; D001156:Artemia / Q000187:drug effects*; D001234:Aspergillus niger / Q000187:drug effects; D001688:Biological Products / Q000494:pharmacology; D001713:Biphenyl Compounds / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D020128:Inhibitory Concentration 50; D008011:Lichens / Q000378:metabolism; D003904:Mitosporic Fungi / Q000187:drug effects*; D010851:Picrates / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D012250:Rheum / Q000737:chemistry; D029793:Rhododendron / Q000737:chemistry; D027824:Rosaceae / Q000737:chemistry; D012426:Russia; D013211:Staphylococcus aureus / Q000187:drug effects; D018675:Toxicity Tests
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D001688:Biological Products; D001713:Biphenyl Compounds; D010851:Picrates; D010936:Plant Extracts; C004931:1,1-diphenyl-2-picrylhydrazyl