title: Study of levan productivity from Bacillus subtilis Natto by surface response methodology and its antitumor activity against HepG2 cells using metabolomic approach.
abstract: Levan productivity of Bacillus subtilis Natto was evaluated in submerged culture varying the pH, temperature and culture time, using factorial design and response surface methodology. The characterization of levan molecular weight was performed by HPSEC and its antitumor activity against HepG2 cells using metabolomic approach was also evaluated. At first, the variables investigated, as well as their interactions, demonstrated significant effect. Further, a second design using the same variables at different levels was developed. Thus, according to the model, an optimized value corresponding to 5.82 g.L⁻¹.h⁻¹ was achieved at pH 8, 39.5°C in 21 hours, the highest value reported so far. After analysis by HPSEC, two molecular weights were obtained corresponding to 72.37 and 4146 kDa. The levan promoted an increase of acetate, alanine, lactate and phosphocreatine in HepG2 cells suggesting an alteration in the bioenergetics pathways and cellular homeostasis by intracellular accumulation of lactate, justifying its antitumor activity.
authors.affiliation: Department of Biochemistry and Biotechnology, Centre of Exact Science, State University of Londrina, Brazil.
authors.forename: Fernando Cesar Bazani
authors.initials: FC
authors.lastname: Cabral de Melo
authors.affiliation: Department of Chemistry, Centre of Exact Science, State University of Londrina, Brazil.
authors.forename: Dionísio
authors.initials: D
authors.lastname: Borsato
authors.affiliation: Department of Chemistry, Centre of Exact Science, State University of Londrina, Brazil.
authors.forename: Fernando César
authors.initials: FC
authors.lastname: de Macedo Júnior
authors.affiliation: Department of General Biology, Centre of Biological Science, State University of Londrina, Brazil.
authors.forename: Mario Sérgio
authors.initials: MS
authors.lastname: Mantovani
authors.affiliation: Department of Pathological Science, Centre of Biological Science, State University of Londrina, Londrina, Parana Stat, Brazil.
authors.forename: Rodrigo Cabral
authors.initials: RC
authors.lastname: Luiz
authors.affiliation: Department of Biochemistry and Biotechnology, Centre of Exact Science, State University of Londrina, Brazil.
authors.forename: Maria Antonia-Pedrine
authors.initials: MA
authors.lastname: Colabone-Celligoi
mesh_terms: D019342:Acetic Acid / Q000378:metabolism; D000409:Alanine / Q000378:metabolism; D000970:Antineoplastic Agents / Q000378:metabolism / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000378:metabolism*; D004734:Energy Metabolism / Q000187:drug effects*; D005285:Fermentation; D005630:Fructans / Q000378:metabolism / Q000494:pharmacology*; D056945:Hep G2 Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000378:metabolism; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D055432:Metabolomics / Q000379:methods; D008970:Molecular Weight; D010725:Phosphocreatine / Q000378:metabolism; D013696:Temperature; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; D005630:Fructans; D010725:Phosphocreatine; D019344:Lactic Acid; C072599:levan; D000409:Alanine; D019342:Acetic Acid