Improved Production of Kynurenic Acid by Yarrowia lipolytica in Media Containing Different Honeys

Magdalena Wróbel-Kwiatkowska,Waldemar Rymowicz,Piotr Juszczyk,Waldemar Turski,Agnieszka Kita

doi:10.3390/su12229424

Magdalena Wróbel-Kwiatkowska, Waldemar Rymowicz + Show 3 more

Open Access

https://doi.org/10.3390/su12229424

Copy DOI

Abstract

Y. lipolytica remains a nonpathogenic, unconventional yeast, which can be applied for the production of bioactive compounds. Our previous study confirmed the ability of yeast Yarrowia lipolytica to produce kynurenic acid (KYNA). Here, we investigated the effectiveness of KYNA production in cultures cultivated in medium containing honey of various origin, used as a source of carbon and energy. It was evidenced that the highest content of KYNA in culture broth (68 mg/L) and yeast biomass (542 mg/kg) was obtained when chestnut honey was used. The content of lipids and amino acids composition in yeast biomass producing KYNA was also determined. It was found that the composition of both amino acids and lipids in yeast biomass depended on the honey type used as a component of the medium. This finding revealed that supplementation of medium broth with honey may significantly affect the nutritional value of yeast biomass. The practical applicability of this finding requires further study.

Highlights

Nowadays, a rising interest in finding new sources of bioactive compounds can be observed
The lowest production of kynurenic acid (KYNA) was noticed in the medium containing lime honey and the lowest content of KYNA in biomass was detected in yeast cultured on rape honey (Figure 1B)
The present study provided new data related to the synthesis of bioactive compounds in yeast

Summary

Introduction

A rising interest in finding new sources of bioactive compounds can be observed. Y. lipolytica is considered an interesting platform for lipid production, and for the production of biomass [2], organic acids as citric acid [3,4] or sweeteners (e.g., erythritol) [5]. We discovered that Y. lipolytica yeast produces a tryptophan metabolite, kynurenic acid (KYNA) [6]. This compound is synthesized in the reaction of kynurenine transamination, which is catalyzed by kynurenine aminotransferases (KATs). The main limitation of KYNA application is its low content in natural sources and low solubility in water and aqueous solutions [10]. Our former study showed that KYNA synthesized by yeast Y. lipolytica strain S12 is present in biomass and culture broth [6]. It should be pointed out that Y. lipolytica was noted as Generally Recognized

Methods

Results

Conclusion