This diploma thesis deals with a cultivation of five yeast strains using plant peptones as a nitrogen source in order to produce biomass that can be used in vegan cosmetics. Namely, the investigated strains included Saccharomyces cerevisiae, Yarrowia lipolytica, Metschnikowia reukaufii, Phaffia rhodozyma, and Komagataella pastoris. For comparison, cultivations in media containing animal peptones were performed as well. The theoretical part discusses natural cosmetics, focusing primarily on cosmetic ingredients derived from microorganisms. Besides the characteristics of the cultivated yeast strains, the literature review also covers the industrial production of yeast biomass, substrates used in cultivation media, and downstream processing of the products. The experimental work mainly consisted of the cultivation of individual yeast strains in complex media composed of glucose, yeast extract, and peptone. A total of six cultivation media, differing in the peptone source, were prepared for each strain. Plant peptones were derived from soybean, pea, potato or wheat, while animal ones came from meat or casein. Simultaneously, cultivations in the absence of yeast extract were performed to eliminate its influence on biomass production. Biomass yield was determined, the total protein content was analysed using the Hartree-Lowry method, β-glucan content was analysed using a commercial kit, and Phaffia rhodozyma metabolites were measured by high-performance liquid chromatography. Subsequently, the yeast biomass was subjected to a three-phase extraction using two different solvent mixtures. The biochemical profile of the yeast biomass and extracts was analysed by infrared spectroscopy. The biomass concentration results confirmed the possible substitution of animal peptones with plant alternatives, among which potato peptone stood out in particular. Yeast growth ranged from 3.944±0.008 g/L to 17.5±0.7 g/L, while the highest value was detected with the Yarrowia lipolytica strain. The analysis of total protein content did not provide unambiguous results regarding the highest production, on the contrary, the lowest values were observed when potato or wheat peptones were used. Higher β-glucan production was stimulated by both plant and animal cultivation variants. No significant differences were observed in carotenoid production in the Phaffia rhodozyma strain, although meat peptone supported the production the most. Additionally, ergosterol levels were higher, particularly in biomass cultivated using plant peptones. The absence of yeast extract in cultivation media led to lower yeast growth, whereas protein and β-glucan production matched or exceeded the levels observed in YPD media. FTIR-ATR analysis did not reveal a significant influence of the peptone source on the biomass biochemical profile, and indicated a probable substance distribution in the biomass extracts.