Microbial lipids called a sustainable alternative to traditional vegetable oils invariably capture the attention of researchers. In this study, the effect of limiting inorganic phosphorus (KH₂PO₄) and nitrogen ((NH₄)₂SO₄) sources in lipid-rich culture medium on the efficiency of cellular lipid biosynthesis by Y. lipolytica yeast has been investigated. In batch cultures, the carbon source was rapeseed waste post-frying oil (50 g/dm³). A significant relationship between the concentration of KH₂PO₄ and the amount of lipids accumulated has been revealed. In the shake-flask cultures, storage lipid yield was correlated with lower doses of phosphorus source in the medium. In bioreactor culture in mineral medium with (g/dm³) 3.0 KH₂PO₄ and 3.0 (NH₄)₂SO₄, the cellular lipid yield was 47.5% (w/w). Simultaneous limitation of both phosphorus and nitrogen sources promoted lipid accumulation in cells, but at the same time created unfavorable conditions for biomass growth (0.78 g_d.m./dm³). Increased phosphorus availability with limited cellular access to nitrogen resulted in higher biomass yields (7.45 g_d.m./dm³) than phosphorus limitation in a nitrogen-rich medium (4.56 g_d.m./dm³), with comparable lipid yields (30% and 32%). Regardless of the medium composition, the yeast preferentially accumulated oleic and linoleic acids as well as linolenic acid up to 8.89%. Further, it is crucial to determine the correlation between N/P molar ratios, biomass growth and efficient lipid accumulation. In particular, considering the contribution of phosphorus as a component of coenzymes in many metabolic pathways, including lipid biosynthesis and respiration processes, its importance as a factor in the cultivation of the oleaginous microorganisms was highlighted.

The review aims to summarize the current knowledge on the possibility of using non-conventional yeast speciesYarrowia lipolyticain the treatment and upgradation of industry wastes. ImportantlyY. lipolyticayeast is argued as generally recognized as safe species, what indicates the high application potential of the reviewed technologies. Special emphasis in the paper was given on microbial processing of the food industry wastes, including fish and animals’ wastes utilization.Yarrowia-based processing of waste cooking oil or oil-bearing plants wastewaters, such as palm oil mill effluents or olive mill wastewater was reviewed. Recent advances in biosynthesis of valuable metabolites (e.g. lipases or microbial oil) with simultaneous wastes utilization byY. lipolyticaare additionally discussed. The broad implications of the present paper are a part of sustainable development policy.Graphic Abstract

There is a growing demand for vegan products and plant-based food when dealing with the impact of livestock on the climate crisis. The aim of this study was to develop a formulation for a plant-based analogue of mold-ripened cheese. Were investigated the following plant materials: cashews, pistachios, soy flour, chickpea flour, pea protein, pumpkin protein, hemp protein, and spirulina powder. Plant matrices were fermented with lactic acid bacteria (LAB) starter cultures and cheese starter cultures of mold species Geotrichum candidum and Penicillium camemberti. All microorganisms’ growth were tested in a vegan-type culture medium. Calcium supplementation was applied and followed by an in-depth analysis of the elemental composition of selected analogues with inductively coupled plasma optical emission spectroscopy. The physicochemical and organoleptic analyses of plant-based alternatives of Camembert were conducted. This is the first paper describing novel formulations for plant-based alternatives for Camembert cheese prepared with techniques mimicking the original milk product.

Yarrowia lipolytica is a robust yeast species that has gained significant attention as a biofactory for various biotechnological applications and undoubtedly can be referred to as a hidden treasure trove due to boasting a diverse array of enzymes with wide-ranging applications in multiple industries, including biofuel production, food processing, biotechnology, and pharmaceuticals. As the biotechnology field continues to expand, Y. lipolytica is poised to play a pivotal role in developing eco-friendly and economically viable bioprocesses. Its versatility and potential for large-scale production make it a promising candidate for sustainably addressing various societal and industrial needs. The current review article aimed to highlight the diverse enzymatic capabilities of Y. lipolytica and provide a detailed analysis of its relevance in biocatalysis, including the use of whole-cell catalysts and isolated enzymes. The review focused on wild-type yeast strains and their species-dependant properties and selected relevant examples of Y. lipolytica used as a host organism for overexpressing some enzymes. Furthermore, the application of Y. lipolytica’s potential in enantiomers resolution, lipids processing, and biodiesel synthesis, as well as the synthesis of polymers or esterification of different substrates for upgrading biologically active compounds, was discussed.

Extraction is one of the most commonly used methods for obtaining and purifying chemical compounds for commercial usage. The aim of this study was to evaluate the effect of unconventional permeabilization and cell disruption methods on the yield of lipid extraction from cells of the oleaginous yeast Yarrowia lipolytica. Batch cultures in a medium with molasses and waste post-frying oil were carried out. The biomass was subjected to pulsed electric field (PEF), high-pressure processing (HPP), ultrasounds (US), and several conventional processing techniques with chemical and mechanical agents (glass beads, acetone, Triton and Tween surfactants). The effectiveness of the applied methods, either on cell permeabilization or cell disruption, was investigated by analyzing the oil and total protein extraction yield and oil leaching efficiency, as well as by using microscope images. The PEF and US treatments proved to be effective permeabilization methods as a step of sample pretreatment for extraction. These unconventional physical methods could efficiently increase intracellular lipid extraction yield in solvent applications.

This study investigated the capabilities of Yarrowia lipolytica strains to grow in media with different hydrophobic wastes from the meat industry. The yeast growth, cellular lipid accumulation, production of lipases, and degree of utilization of liquid and solid lipid wastes were studied in shaken cultures in media with organic and inorganic nitrogen sources. The effects of the type of waste, initial concentration of carbon source, Yarrowia strain, and inoculum size were investigated in two experimental sets using the Latin Square 5 × 5 design method. Post-frying rapeseed oil from chicken frying was selected as the carbon source to promote biomass growth. In contrast, the solid lipid fraction from meat broths promoted efficient lipid accumulation and yeast lipolytic activity. An initial concentration of the carbon source at 8% m/v stimulated efficient lipid biosynthesis and lipase production, while 2.5% v/v inoculum provided optimal conditions for the growth and utilization of hydrophobic substrates. No significant differences were observed in the particle dispersion of the liquid and solid wastes in the culture media (span = 2.51–3.23). The maximum emulsification index (62%) was observed in the culture of the Y. lipolytica KKP 323 strain in the medium with post-frying rapeseed oil from chicken frying, which was correlated with biosurfactant synthesis. It was concluded that the type of waste, its structure, and its composition affected various physiological yeast responses.