Polar Lipids of Brewer's Yeasts

Abstract

Both traditional and DNA-based methods sometimes fail to differentiate between closely related strains of commercial interest in the brewing industry. The aim of this study was to compare species and sub species of Saccharomyces cerevisiae on the basis of their polar lipid chemistry using chromatographic methods. Six isolates were studied after propagation under batch conditions. Polar lipids were then extracted from lyophilised cultures and analysed by TLC in order to separate phospholipid families. TLC showed that the major phospholipid classes present were PC > PE > PG. Two unidentified phospholipids were found, one only in strain 34 /70. The major peaks detected by GLC were identified as methyl esters of palmitic acid and palmitoleic acid. The fatty acid composition of PC varied between strains and novel data on lecithin acyl constituents were observed. The polar lipid method succeeded in differentiating strain 34 /70 -one of the most commonly used brewer's lager yeast -from strain 34 /78 and other species tested. The presence of unusual polar lipids in Saccharomyces sensu stricto yeasts may be useful in distinguishing between other closely related strains.

Self-selection of food ingredients and agricultural by-products by the house cricket, Acheta domesticus (Orthoptera: Gryllidae): A holistic approach to develop optimized diets

“…The ratios of carbohydrate (Cr) and lipid (Lr) were calculated in the same manner and the sum of Pr + C r+ Lr = 1 [17]. The nutrient content information of food products and spirulina algae was obtained from the USDA nutrient database [22], for the by-products this information was obtained from several published sources [23,24,25,26,27,28,29,30,31,32,33,34,35,36]. In addition, information provided by the distributors that donated their products for this study (Ergon Biofuels, Big River Resources Galva LLC, Riceland Foods Inc., Express Grain Terminals LLC, and ADM Processing Co.) was cross referenced with published information on by-product nutrient content.…”

Molecular species of phosphatidylethanolamine from continuous cultures of Saccharomyces pastorianus syn. carlsbergensis strains

“…In contrast, other ions, diagnostic for strain 34/78 were found ( m / z 251 and m / z 295) and identified as C 16 : 2 , and C 19 : 1 . Recently, Tosch et al (2005) have provided corroborative gas chromatographic evidence for fatty acids of C 16 : 2 and C 18 : 2 detected in PC of bottom‐fermenting strains.…”

Yeast and its uses.

“…Lipids exist in cells in the bound form in cell wall or as fat drops in the cytoplasm. Lipids are composed to a large extent by glycolipids and phospholipids -lecithin and cephalin (Tosch et al, 2005). Mineral compounds contained in the cell include P 2 O 5 , calcium, magnesium, copper, manganese and zinc (Němec and Horáková, 2002).…”

“…Lipidy jsou v buňkách obsaženy jako tuky vázané v buněčné stěně nebo jako tuky volné v cytoplasmě ve formě tukových kapének. Podstatnou část lipidické složky zaujímají složené tuky, především glykolipidy a fosfolipidy -lecitin a kefalin (Tosch et al, 2005). Z minerálních látek je nejvíce zastoupen P 2 O 5 , vápník, hořčík, měď, mangan a zinek (Němec a Horáková, 2002).…”