Growth tolerance of Zygomycetes Mucor indicus in orange peel hydrolysate without detoxification
Artikel i vetenskaplig tidskrift, 2012

The capability of two zygomycetes strains, Mucor indicus and an isolate from tempeh (Rhizopus sp.), to grow on orange peel hydrolysate and their tolerance to its antimicrobial activity, was investigated. Both fungi, in particular M. indicus, tolerated up to 2% d-limonene in semi-synthetic media during cultivation in shake flasks, under aerobic as well as anaerobic conditions. The tolerance of M. indicus was also tested in a bioreactor, giving rise to varying results in the presence of 2% limonene. Furthermore, both strains were capable of consuming galacturonic acid, the main monomer of pectin, under aerobic conditions when no other carbon source was present. The orange peel hydrolysate was based on 12% (dry w/v) orange peels, containing d-limonene at a concentration of 0.6% (v/v), which no other microorganism has been reported to be able to ferment. However, the hydrolysate was utilised by M. indicus under aerobic conditions, resulting in production of 410 and 400 mg ethanol/g hexoses and 57 and 75 mg fungal biomass/g sugars from cultivations in shake flasks and a bioreactor, respectively. Rhizopus sp., however, was slow to germinate aerobically, and neither of the zygomycetes was able to consistently germinate in orange peel hydrolysate, under anaerobic conditions. The zygomycetes strains used in the present study demonstrated a relatively high resistance to the antimicrobial compounds present in orange peel hydrolysate, and they were capable of producing ethanol and biomass in the presence of limonene, particularly when cultivated with air supply.

Zygomycetes

Mucor indicus

Orange peel

Ethanol

D-Limonene

Författare

Patrik R Lennartsson

Chalmers, Kemi- och bioteknik, Kemisk reaktionsteknik

Päivi Ylitervo

Chalmers, Kemi- och bioteknik, Industriell Bioteknik

Christer Larsson

Chalmers, Kemi- och bioteknik, Molekylär mikroskopi

Lars Edebo

Göteborgs universitet

Mohammad Taherzadeh Esfahani

Högskolan i Borås

Process Biochemistry

1359-5113 (ISSN)

Vol. 47 836-842

Drivkrafter

Hållbar utveckling

Ämneskategorier

Industriell bioteknik

Styrkeområden

Energi

DOI

10.1016/j.procbio.2012.02.019