Next Article in Journal
AfAP2-1, An Age-Dependent Gene of Aechmea fasciata, Responds to Exogenous Ethylene Treatment
Next Article in Special Issue
Hydrogen Production by a Chlamydomonas reinhardtii Strain with Inducible Expression of Photosystem II
Previous Article in Journal
The Human Host Defense Ribonucleases 1, 3 and 7 Are Elevated in Patients with Sepsis after Major Surgery—A Pilot Study
Previous Article in Special Issue
Xylose Fermentation by Saccharomyces cerevisiae: Challenges and Prospects
Article Menu
Issue 3 (March) cover image

Export Article

Open AccessArticle
Int. J. Mol. Sci. 2016, 17(3), 302; doi:10.3390/ijms17030302

Co-Production of Fungal Biomass Derived Constituents and Ethanol from Citrus Wastes Free Sugars without Auxiliary Nutrients in Airlift Bioreactor

1
Swedish Centre for Resource Recovery, University of Borås, 50190 Borås, Sweden
2
Department of Chemical Engineering, Isfahan University of Technology, Isfahan 84156-83111, Iran
*
Author to whom correspondence should be addressed.
Academic Editor: ChulHee Kang
Received: 15 December 2015 / Revised: 13 February 2016 / Accepted: 16 February 2016 / Published: 26 February 2016
(This article belongs to the Special Issue Biofuel)
View Full-Text   |   Download PDF [2355 KB, uploaded 26 February 2016]   |  

Abstract

The potential of two zygomycetes fungi, Mucor indicus and Rhizopus oryzae, in assimilating citrus waste free sugars (CWFS) and producing fungal chitosan, oil, and protein as well as ethanol was investigated. Extraction of free sugars from citrus waste can reduce its environmental impact by decreasing the possibility of wild microorganisms growth and formation of bad odors, a typical problem facing the citrus industries. A total sugar concentration of 25.1 g/L was obtained by water extraction of citrus waste at room temperature, used for fungal cultivation in shake flasks and airlift bioreactor with no additional nutrients. In shake flasks cultivations, the fungi were only able to assimilate glucose, while fructose remained almost intact. In contrast, the cultivation of M. indicus and R. oryzae in the four-liter airlift bioreactor resulted in the consumption of almost all sugars and production of 250 and 280 g fungal biomass per kg of consumed sugar, respectively. These biomasses correspondingly contained 40% and 51% protein and 9.8% and 4.4% oil. Furthermore, the fungal cell walls, obtained after removing the alkali soluble fraction of the fungi, contained 0.61 and 0.69 g chitin and chitosan per g of cell wall for M. indicus and R. oryzae, respectively. Moreover, the maximum ethanol yield of 36% and 18% was obtained from M. indicus and R. oryzae, respectively. Furthermore, that M. indicus grew as clump mycelia in the airlift bioreactor, while R. oryzae formed spherical suspended pellets, is a promising feature towards industrialization of the process. View Full-Text
Keywords: chitosan; citrus waste; ethanol; Mucor indicus; oil; pellet; protein; Rhizopus oryzae chitosan; citrus waste; ethanol; Mucor indicus; oil; pellet; protein; Rhizopus oryzae
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Satari, B.; Karimi, K.; Taherzadeh, M.J.; Zamani, A. Co-Production of Fungal Biomass Derived Constituents and Ethanol from Citrus Wastes Free Sugars without Auxiliary Nutrients in Airlift Bioreactor. Int. J. Mol. Sci. 2016, 17, 302.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top