Isolation and Characterization of Fusarium verticillioides NKF1 for Unsaturated Fatty Acid Production

The Lipid Profile of the Endomyces magnusii Yeast upon the Assimilation of the Substrates of Different Types and upon Calorie Restriction

The study analyzes the dynamics in the lipid profile of the Endomyces magnusii yeast during the long-lasting cultivation using the substrates of “enzymatic” or “oxidative” type. Moreover, we studied its changes upon calorie restriction (CR) (0.5% glucose) and glucose depletion (0.2% glucose). Di-(DAGs), triacylglycerides (TAGs) and free fatty acids (FFAs) dominate in the storage lipid fractions. The TAG level was high in all the cultures tested and reached 80% of the total lipid amount. While being cultured on 2% substrates, the level of storage lipids decreased at the four-week stage, whereas upon CR their initially low amount doubled. Phosphatidylethanolamines (PE), sterols (St) (up to 62% of total lipids), phosphatidylcholines (PC), and phosphatidic acids (PA) (more than 40% of total lipids) were dominating in the membrane lipids of E magnusii. Upon CR at the late stationary growth stages (3–4 weeks), the total level of membrane lipid was two-fold higher than those on glycerol and 2% glucose. The palmitic acid C16:0 (from 10 to 23%), the palmitoleic acid C16:1 (from 4.3 to 15.9%), the oleic acid C18:1 (from 23.4 to 59.2%), and the linoleic acid C18:2 (from 10.8 to 49.2%) were the dominant fatty acids (FAs) of phospholipids. Upon glucose depletion (0.2% glucose), the total amount of storage and membrane lipids in the cells was comparable to that in the cells both on 2% and 0.5% glucose. High levels of PC and sphingolipids (SL) at the late stationary growth stages and an increased PA level throughout the whole experiment were typical for the membrane lipids composition upon the substrate depletion. There was shown a crucial role of St, PA, and a high share of the unsaturated FAs in the membrane phospholipids upon the adaptation of the E. magnusii yeast to the long-lasting cultivation upon the substrate restriction is shown. The autophagic processes in some fractions of the cell population provide the support of high level of lipid components at the late stages of cultivation upon substrate depletion under the CR conditions. CR is supposed to play the key role in regulating the lipid synthesis and risen resistance to oxidative stress, as well as its possible biotechnological application.

Effect of Carbon Sources on the Production of Volatile Organic Compounds by Fusarium verticillioides

The aim of the present study was to evaluate the effect of different carbon sources on the hydrocarbon-like volatile organic compounds (VOCs) of Fusarium verticillioides strain 7600 through a Principal Component Analysis approach, and to explore their diesel potential by using data from the literature. The fungus was cultivated in GYAM culture medium, and five carbon sources were evaluated: glucose, sucrose, xylose, lactose, and fructose. The VOCs were collected using a close-loop apparatus and identified through GC-MS. The same profile of 81 VOCs was detected with all treatments, but with different relative percentages among carbon sources. The production of branched-chain alkanes (30 compounds) ranged from 25.80% to 38.64%, straight-chain alkanes (12 compounds) from 22.04% to 24.18%, benzene derivatives (12 compounds) from 7.48% to 35.58%, and the biosynthesis of branched-chain alcohols (11 compounds) was from 6.82% to 16.71%, with lower values for the remaining groups of VOCs. Our results show that F. verticillioides has the metabolic potential to synthesize diesel-like VOCs. Further research should include the optimization of culture conditions other than carbon sources to increase the production of certain groups of VOCs.

Acautalides A-C, Neuroprotective Diels-Alder Adducts from Solid-State Cultivated Acaulium sp. H-JQSF

The solid-state cultivation of Acaulium sp. H-JQSF isolated from Armadillidium vulgare produces acautalides A-C (1-3) as skeletally unprecedented Diels-Alder adducts of a 14-membered macrodiolide to an octadeca-9,11,13-trienoic acid. The acautalide structures, along with the intramolecular transesterifications of 1-acylglycerols, were elucidated by mass spectrometry, nuclear magnetic resonance, chemical transformation, and single-crystal X-ray diffraction. Compounds 1-3 were found to be neuroprotective with antiparkinsonic potential in the 1-methyl-4-phenylpyridinium-challenged nematode model, with the magnitude impacted by the glycerol esterification.