Development of a cost-effective production process for Halomonas levan

Erkorkmaz B. A., Kirtel O., Duru O. A., Oner E. T.

BIOPROCESS AND BIOSYSTEMS ENGINEERING, cilt.41, sa.9, ss.1247-1259, 2018 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 41 Sayı: 9
  • Basım Tarihi: 2018
  • Doi Numarası: 10.1007/s00449-018-1952-x
  • Dergi Adı: BIOPROCESS AND BIOSYSTEMS ENGINEERING
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1247-1259
  • Anahtar Kelimeler: Exopolysaccharide, Levan, Halomonas smyrnensis, Microbial bioprocess, Cost-effective production, SMYRNENSIS AAD6(T), ZYMOMONAS-MOBILIS, MICROBIAL LEVAN, BIOMEDICAL APPLICATIONS, BACILLUS-SUBTILIS, MOLECULAR-WEIGHT, MULTILAYER FILMS, SULFATED LEVAN, TRACE-METALS, LEVANSUCRASE
  • Marmara Üniversitesi Adresli: Evet

Özet

Levan polysaccharide is an industrially important natural polymer with unique properties and diverse high-value applications. However, current bottlenecks associated with its large-scale production need to be overcome by innovative approaches leading to economically viable processes. Besides many mesophilic levan producers, halophilic Halomonas smyrnensis cultures hold distinctive industrial potential and, for the first time with this study, the advantage of halophilicity is used and conditions for non-sterile levan production were optimized. Levan productivity of Halomonas cultures in medium containing industrial sucrose from sugar beet and food industry by-product syrup, a total of ten sea, lake and rock salt samples from four natural salterns, as well as three different industrial-grade boron compounds were compared and the most suitable low-cost substitutes for sucrose, salt and boron were specified. Then, the effects of pH control, non-sterile conditions and different bioreactor modes (batch and fed-batch) were investigated. The development of a cost-effective production process was achieved with the highest yield (18.06 g/L) reported so far on this microbial system, as well as the highest theoretical bioconversion efficiency ever reported for levan-producing suspension cultures. Structural integrity and biocompatibility of the final product were also verified in vitro.