Exploring the extremes: applying high concentration of yeast extract leads to drastic morphological changes and eliminat
- PDF / 1,746,865 Bytes
- 11 Pages / 547.087 x 737.008 pts Page_size
- 90 Downloads / 181 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL RESEARCH PAPER
Exploring the extremes: applying high concentration of yeast extract leads to drastic morphological changes and elimination of (+)-geodin and asterric acid production in Aspergillus terreus submerged cultures Tomasz Boruta . Adrianna Go´rnicka . Iwona Grzybowska . Ida Stefaniak . Marcin Bizukojc´
Received: 12 May 2020 / Accepted: 29 September 2020 Ó The Author(s) 2020
Abstract Objective Evaluation of morphology and secondary metabolites production in Aspergillus terreus ATCC 20542 cultures over a wide range of lactose and yeast extract concentrations from 0.2 up to an extremely high level of 200 g l-l. Results The morphological differences of mycelial objects were quantified with the use of morphological parameters calculated by applying the tools of digital image analysis. At 200 g l-l of yeast extract clumps and loose hyphae were recorded instead of pellets commonly observed in submerged cultures of A. terreus. Under these conditions the biosynthesis of (?)-geodin and asterric acid was totally blocked, lovastatin formation was found to be at a relatively low level and biomass production turned out to be greater than in the remaining variants, where the pelleted growth was observed. At 200 g l-l of lactose the production of lovastatin, (?)-geodin and asterric acid was visibly stimulated compared to the media
Electronic supplementry material The online version of this article (https://doi.org/10.1007/s10529-020-03018-5) contains supplementary material, which is available to authorized users. T. Boruta (&) A. Go´rnicka I. Grzybowska I. Stefaniak M. Bizukojc´ Faculty of Process and Environmental Engineering, Department of Bioprocess Engineering, Lodz University of Technology, ul. Wolczanska 213, 90-924 Lodz, Poland e-mail: [email protected]
containing 0.2, 2 and 20 g l-l of the sugar substrate, but at the same time no traces of butyrolactone I could be detected in the broth. Lactose at the extremely high concentration of 200 g l-l did not induce the drastic morphological changes observed in the case of 200 g l1 of yeast extract. It was proved that at the C/N values as low as 4 and as high as 374 A. terreus not only continued to display growth but also exhibited the production of secondary metabolites. The use of cultivation media representing the equivalent C/N ratios led to different metabolic and morphological outcomes depending on the concentration of lactose and yeast extract that contributed to the given C/N value. Conclusion The extremely high concentration of yeast extract leads to marked morphological changes of A. terreus and the elimination of (?)-geodin and asterric production, while applying the excess of lactose is stimulatory in terms of lovastatin production. Keywords Aspergillus terreus Fungal morphology Lovastatin Secondary metabolites Yeast extract
Introduction The repertoire of fungal secondary metabolites is a rich source of bioactive substances of potential
123
Biotechnol Lett
pharmaceutical int
Data Loading...
