Production of Enriched Sporidiobolus sp. Yeast Biomass Cultivated on Mixed Coffee Hydrolyzate and Fat/Oil Waste Materials

One of the most addressed topics today is the transfer from a linear model of economics to a model of circular economics. It is a discipline that seeks to eliminate waste produced by various industries. The food industry generates huge amounts of waste worldwide, particularly the coffee industry, and related industries produce millions of tons of waste a year. These wastes have potential utility in biotechnology, and in the production of energy, fuels, fertilizers and nutrients, using green techniques such as anaerobic digestion, co-digestion, composting, enzymatic action, and ultrasonic and hydrothermal carbonization. This work is focused on the biotechnological use of processed spent coffee grounds (SCG) and waste fat/oil materials by some Sporidiobolus sp. carotenogenic yeasts in the model of circular economics. The results show that selected yeast strains are able to grow on SCG hydrolysate and are resistant to antimicrobial compounds present in media. The most productive strain Sporidiobolus pararoseus CCY19-9-6 was chosen for bioreactor cultivation in media with a mixture of coffee lignocellulose fraction and some fat wastes. Sporidiobolus pararoseus CCY19-9-6 was able to produce more than 22 g/L of biomass in mixture of SCG hydrolysate and both coffee oil and frying oil. The combined waste substrates induced the production of lipidic metabolites, whereby the production of carotenoids exceeded 5 mg/g of dry biomass. On media with coffee oil, this strain produced high amounts of ubiquinone (8.265 +/- 1.648 mg/g) and ergosterol (13.485 +/- 1.275 mg/g). Overall, the results prove that a combination of waste substrates is a promising option for the production of carotenoid- and lipid-enriched yeast biomass

Revealing the Potential of Lipid and beta-Glucans Coproduction in Basidiomycetes Yeast

Beta (beta)-glucans are polysaccharides composed of D-glucose monomers. Nowadays, beta-glucans are gaining attention due to their attractive immunomodulatory biological activities, which can be utilized in pharmaceutical or food supplementation industries. Some carotenogenicBasidiomycetesyeasts, previously explored for lipid and carotenoid coproduction, could potentially coproduce a significant amount of beta-glucans. In the present study, we screened elevenBasidiomycetesfor the coproduction of lipids and beta-glucans. We examined the effect of four different C/N ratios and eight different osmolarity conditions on the coproduction of lipids and beta-glucans. A high-throughput screening approach employing microcultivation in microtiter plates, Fourier Transform Infrared (FTIR) spectroscopy and reference analysis was utilized in the study. Yeast strainsC. infirmominiatumCCY 17-18-4 andR. kratochvilovaeCCY 20-2-26 were identified as the best coproducers of lipids and beta-glucans. In addition,C. infirmominiatumCCY 17-18-4,R. kratochvilovaeCCY 20-2-26 andP. rhodozymaCCY 77-1-1 were identified as the best alternative producers of beta-glucans. Increased C/N ratio led to increased biomass, lipid and beta-glucans production for several yeast strains. Increased osmolarity had a negative effect on biomass and lipid production while the beta-glucan production was positively affected

Optimization of extraction of pigments from yeast and algae cells

The presented diploma thesis deals with the extraction and storage stability of lipophilic pigments produced by selected strains of yeasts and algae. In this thesis, there was studied the influence of the selected solvents on the efficiency of extraction, as well as the effect of ambient temperature on the stability of the pigments during storage. The work is divided into two main parts, theoretical and practical part. In the theoretical part knowledge about algae, yeasts and their cultivation parameters is summarized. Furthermore, some information regarding the selected lipid metabolites, their properties and possibilities of application in various branches of industry is mentioned. The practical part deals with the preparation of extracts and stability tests. Extracts were prepared from selected biomass samples in solvents suitable for applications in food industry or cosmetics (ethanol and hexane). Subsequently, the long-term stability tests lasting 4 months and short-term stability tests lasting a total of 28 days were performed on these extracts. The pigments were determined by HPLC and spectrophotometrically, the fatty acid content was determined by GC. For the extraction of pigments from biomass, in the most cases ethanol appears to be the optimal solvent. However, for lipid extraction from biomass, hexane appears to be the optimal solvent for a significant number of samples. In most samples, storage in the freezer showed the most favourable effect on pigment stability, but some samples showed comparable stability even when stored in the refrigerator

Production of lipids and lipid-soluble compounds by some yeasts and algae

Předložená bakalářská práce se zabývá produkcí lipidů a lipidických metabolitů vybranými kmeny karotenogenních kvasinek, autotrofních řas a sinic. Na vybrané kmeny byly aplikovány různé formy stresu a jejich vliv byl následně srovnán. Teoretická část se zabývá zpracováním poznatků o vybraných kmenech kvasinek, řas a sinic. Dále jsou zmíněny sledované metabolity (lipidy, karotenoidy, ergosterol, ubichinon a chlorofyl) a možnosti jejich stanovení. Experimentální část se zabývá zejména sledováním vlivu nutričního stresu na produkci vybraných metabolitů a biomasy kvasinkami, konkrétně jejich růstových vlastností na odpadním tuku. Dále je sledován vliv zvýšené a snížené teploty na kultivaci kvasinek, řas a sinic. Taktéž byli provedeny experimenty za osmotického stresu, způsobeného přídavkem NaCl. Pro rozklad odpadního tuku byl vybrán jako nejvhodnější kmen Sporidiobolus pararoseus, a to zejména kvůli jeho nadprůměrnému obsahu karotenoidů, ergosterolu a ubichinonu v biomase. Modifikace teploty anebo zvýšený osmotický stres měly ve většině případů negativní vliv na produkci biomasy.The submitted bachelor thesis focuses on production of lipids and lipid-soluble compounds by selected strains of carotenogenic yeasts, autotrophic algae and cyanobacteria. Different forms of stress were applied on selected strains and its influence was subsequently compared. The theoretical part deals with the processing of knowledge about selected strains of yeast, algae and cyanobacteria. There are also mentioned the selected metabolites (lipids, carotenoids, ergosterol, ubiquinone and chlorophyll) and the possibilities of their determination. The experimental part deals primarily with the influence of nutritional stress on the production of selected metabolites and the yeast biomass, namely their growth properties on waste fat. Furthermore, there was monitored the effect of elevated and reduced temperature on the cultivation of yeasts, algae and cyanobacteria. Osmotic stress experiments were also carried out by the addition of NaCl. As the most suitable strain for decomposition of the waste fat was selected Sporidiobolus pararoseus, particularly because of its high content of carotenoids, ergosterols and ubiquinone in biomass. Changes in temperature, or increased osmotic pressure had in the most cases a negative effect on biomass production.

Bioreactor Co-Cultivation of High Lipid and Carotenoid Producing Yeast Rhodotorula kratochvilovae and Several Microalgae under Stress

The co-cultivation of red yeasts and microalgae works with the idea of the natural transport of gases. The microalgae produce oxygen, which stimulates yeast growth, while CO2 produced by yeast is beneficial for algae growth. Both microorganisms can then produce lipids. The present pilot study aimed to evaluate the ability of selected microalgae and carotenogenic yeast strains to grow and metabolize in co-culture. The effect of media composition on growth and metabolic activity of red yeast strains was assessed simultaneously with microalgae mixotrophy. Cultivation was transferred from small-scale co-cultivation in Erlenmeyer flasks to aerated bottles with different inoculation ratios and, finally, to a 3L bioreactor. Among red yeasts, the strain R. kratochvilovae CCY 20-2-26 was selected because of the highest biomass production on BBM medium. Glycerol is a more suitable carbon source in the BBM medium and urea was proposed as a compromise. From the tested microalgae, Desmodesmus sp. were found as the most suitable for co-cultivations with R. kratochvilovae. In all co-cultures, linear biomass growth was found (144 h), and the yield was in the range of 8.78-11.12 g/L of dry biomass. Lipids increased to a final value of 29.62-31.61%. The FA profile was quite stable with the UFA portion at about 80%. Around 1.98-2.49 mg/g CDW of carotenoids with torularhodine as the major pigment were produced, ubiquinone production reached 5.41-6.09 mg/g, and ergosterol yield was 6.69 mg/g. Chlorophyll production was very low at 2.11 mg/g. Pilot experiments have confirmed that carotenogenic yeasts and microalgae are capable of symbiotic co-existence with a positive impact om biomass growth and lipid metabolites yields