3 years ago

Evolutionary adaptation of Kluyveromyces marxianus strain for efficient conversion of whey lactose to bioethanol

Evolutionary adaptation of Kluyveromyces marxianus strain for efficient conversion of whey lactose to bioethanol
The aim of the present work is to develop an osmotolerant yeast strain with high lactose utilization and further use it to ferment lactose rich whey permeate for high ethanol titer and to reduce energy consumption. Ethanol production and growth rate of selected MTCC 1389 strain were quite high in whey containing lactose up to 150g/L but it remains constant in lactose concentration (200g/L) as cells encountered osmotic stress. Thus, strain MTCC 1389 was used for an adaptation to lactose concentration 200g/L for 65days and used further for fermentation of lactose rich whey. Fermentation with an adapted K. marxianus MTCC 1389 strain in laboratory fermenter resulted in ethanol titer of 79.33g/L which is nearly 17.5% higher than the parental strain (66.75g/L). Expression analysis of GPD1, TPS1and TPS2 found upregulated in lactose adapted K. marxianus strain as compared to the parental strain. These results suggest that an adapted K. marxianus strain accumulates glycerol and trehalose in response to lactose stress and improve osmotolerance in K. marxianus cells. Thus, the study illustrates that evolutionary engineering is an efficient strategy to obtain a superior biofuel yeast strain, which efficiently ferments four-fold concentrated cheese whey.

Publisher URL: www.sciencedirect.com/science

DOI: S135951131730870X

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.