Ethanol Candida

Acetaldehye Ethanol Candida utilis Pungent, ethereal-nauseating... 

Ethyl acetate Ethanol Candida utilis Ethereal-fruity... 

Respiratory, or oxidative, metaboHsm produces more energy than fermentation. Complete oxidation of one mol of glucose to carbon dioxide and water may produce up to 36 mol ATP in the tricarboxyHc acid (TCA) cycle or related oxidative pathways. More substrates can be respired than fermented, including pentoses (eg, by Candida species), ethanol (eg, by Saccharomjces), methanol (eg, by Hansenu/a species), and alkanes (eg, by Saccharomjces lipoljticd). 

In all fermented foods, microbes contribute as preservatives, ie, by lowering the pH and producing ethanol, or by making the food more palatable. The dehberate use of yeasts as food in themselves is less common. Small beer, the sediment from beer, has been traditionally used as a vitamin supplement for infants. Beginning in 1910, dried, spent brewers yeast was developed as a food, and Candida utilis was used as a food supplement in Germany during World War II. 

Ethanol can be produced relatively cheaply as a bulk petrochemical by the hydration to ethylene. A few processes operate in the USA using ethanol to produce food-grade Candida utilis, with capacity of about 7,000 tonnes per year. The technology is similar to that already described for SCP from sugars. On ethanol, the yield is about 0.7 kg dry wt per kg ethanol used. 

One of the more recent innovative approaches was to look for new micro-organisms and novel carbohydrate substrates. The early fermentations used sugar beet or cane molasses, various syrups, sweet potato starch or glucose itself and the micro-organism was always an Aspergillus spp. In the early 1930 s it was found that yeasts would produce dtric add from acetate. Since then a variety of yeasts, prindpally Candida spp., has been shown to convert glucose, w-alkanes or ethanol to dtric add with great effidency. 

The chiral intermediate (S)-l-(2 -bromo-4 -fluorophenyl) ethanol was prepared by the enantioselective microbial reduction of 2-bromo-4-fiuoroacetophenone [lObj. Organisms from genus Candida, Hansmula, Pichia, Rhodotcnda, Saccharomyces, Sphingomonas, and baker s yeast reduced the ketone to the corresponding alcohol in... 

The dynamic behavior of the cell metabolism initiated by different external effects (addition of substrates or inhibiting reagents) can be followed via this instantaneous method. These effects can be used to control the overall process and optimize the bioprocess. Meyer and Beyeler [50] developed a control system for a continuous yeast cultivation process. Here the increase up to the optimal dilution rate was controlled via fluorescence monitoring. The dilution rate was only increased when no negative effect on the metabolic state of the cells was observed. During the cultivation of Candida utilis the fluorescence signal was used for the addition of substrate ethanol. The addition was started when... 

Anti-yeast activity. Ethanol (100%) extract of the seed, on agar plate at a concentration of 18.7 mg/mL, was active on Candida albicans. Water extract of the seed, on agar plate was inactive on Candida albicans °b Arrhythmogenic effect. Hot water extract of the dried seed, administered orally to adults with cardiac abnormalities at a dose of 200 mg/person, produced equivocal effect . 

Anti-yeast activity. Ethanol (50%) extract of the dried root, on agar plate at a concentration of 500 mg/mL, was inactive on Candida albicans and Saccharomyces pasta-rianus°. ... 

Anti-yeast activity. The essential oil, on agar plate, was inactive on Saccharomyces cervisiae ° . Ethanol (95%) extract of the dried rhizome, in broth culture at a concentration of 10%, was inactive on Candida albicans, Candida glabrata, and Candida tropicalis ° °. Ethanol (90%) extract of the dried rhizome, on agar plate at a concentration of 500 mg/disc, was inactive on Candida albicans ° ... 

Prior to fermentation, the wort is then cooled to temperatures below 85°F (30°C), and the pH is adjusted to about 5. Yeast such as Saccharomyces cerevisiae, Saccharomyces carlsbergensis or Candida brassicae are added and fermentation proceeds for 2 to 3 days under batch processing conditions. Yeast produces the enzymes maltase, zymase, and invertase. Maltase converts maltose to glucose. Zymase converts glucose to ethanol. Invertase converts any sucrose present to fermentable sugar. The following equations illustrate the enzymatic conversion of starch to ethanol ... 

Kinetic resolution of branched-chain fatty acids has been reported recently by Franssen et al. [24]. With the help of immobilised Candida antarctica lipase B, racemic 4-methyloctanoic acid (responsible for sheep-like and goat-like flavours in sheep and goat milk and cheese, respectively) was esterified with ethanol. Only the R ester could be obtained, whereas (S)-4-methyloctanoic acid was not converted (Scheme 22.1). 

Gatfield et al. [44] reported in 2001 a method to produce natural ethyl E,Z)-2,4-decadienoate, the impact compound of pear. Immobilised lipase from Candida antarctica is capable of transesterifying Stillingia oil in the presence of ethanol. By this process, a complex mixture of ethyl esters is generated. By fractional distillation, the ethyl ester of ( ,Z)-2,4-decadienoate can be isolated from the mixture in a total yield of about 5% and with a high degree of purity. As only... 

E. Akyilmaz and E. Dingkaya, An amperometric microbial biosensor development based on Candida tropicalis yeast cells for sensitive determination of ethanol, Biosens. Bioelectron., 20(7) (2005) 1263-1269. 

Gunnlaugsdottir et al. (1998a, 1998b) Batch/continuous Alcoholysis of cod liver oil with ethanol and glycerolysis Lipase from Candida antarctica... 

Perego et al. (20) found that during the fermentation of hemicellu-lose hydrolysates by Candida shehatae, the addition of 50 mM acetone resulted in ethanol yields comparable with those obtained under micro-aerophilic conditions. Thus, the addition of 50 mM acetone to the culture... 

Gao, C. and Fleet, G. H. (1988). The effects of temperature and pH on the ethanol tolerance of the wine yeasts, Saccharomyces cerevisiae, Candida stellata and Kloeckera apiculata. ]. Appl. Bacteriol. 65,405-410. 

Csajagi et al. (2008) recently demonstrated the enantioselective acylation of racemic alcohols in a continuous flow bioreactor, using Candida antarctica lipase B (CaLB) 167. Employing a packed-bed reactor, containing 0.40 g of enzyme 167, and pumping a solution of rac-phenyl-1-ethanol 119 (10 mg ml-1) in hexane THF vinyl acetate 168 (2 1 1) at a flow rate of 100 gl min-1 (at 25 °C), the authors found the reactor reached steady state after 30 min of operation. Under the aforementioned conditions, the... 

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