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C Millán

Publications and source records attributed to C Millán.

9 recordsLinked to original sources
PubMed2006

Relationship between ethanol tolerance, H+ -ATPase activity and the lipid composition of the plasma membrane in different wine yeast strains.

Ethanol tolerance, ATPase activity and the lipid composition of the plasma membrane to study potential relationship among them were examined in five different wine yeast strains. Yeast cells were subjected to ethanol stress (4% v/v). Principal component analysis of the results revealed that the wine yeasts studied can be distinguished in terms of ATPase activity and oleic acid (C18:1), and palmitoleic acid (C16:1), in plasma membrane. Multiple regression analysis was used to identify a potential influence of some components of the plasma membrane on ethanol tolerance and ATPase activity. Based on the results, the ergosterol, oleic acid and palmitoleic acid are highly correlated with ATPase activity and ethanol tolerance. Ethanol tolerance and the ATPase activity of the plasma membrane were correlated at the 96.64% level with the oleic acid and ergosterol in plasma membrane. The Saccharomyces cerevisiae var. capensis flor yeast strain, which exhibited the highest ergosterol concentration in plasma membrane when grown in the presence of 4% v/v ethanol, was found to be the most ethanol-tolerant.

Adenosine Triphosphatases↗
PubMed2001

Changes in nitrogen compounds in must and wine during fermentation and biological aging by flor yeasts.

Urea, ammonium, and free amino acid contents were quantified in a must from Vitis vinifera cv. Pedro Ximenez grapes and in fermented wine and after a short aging of this wine by Saccharomyces cerevisiae race capensis yeast under variable oxygen availability conditions. The previous compounds were also determined in a wine in which the nitrogen source was depleted by the same race of flor yeast (old wine) and also following the addition of ammonium ion, L-glutamic acid, and L-proline. Under specific conditions such as low oxygen level and the absence of some nutrients, the yeasts release some amino acids including L-threonine, L-tryptophan, L-cysteine, and L-methionine to the medium. These amino acids must originate primarily in a de novo synthesis from ethanol that regenerates NAD(P)+. On the basis of these results, the yeasts may be able to use amino acids not only as nitrogen sources but also as redox agents to balance the oxidation-reduction potential under conditions of restricted oxygen, when electron transport along the respiratory chain may be hindered or limited.

Aging↗
PubMed2001

High-affinity sodium-vitamin C co-transporters (SVCT) expression in embryonic mouse neurons.

The sodium-vitamin C co-transporters SVCT1 and SVCT2 transport the reduced form of vitamin C, ascorbic acid. High expression of the SVCT2 has been demonstrated in adult neurons and choroid plexus cells by in situ hybridization. Additionally, embryonic mesencephalic dopaminergic neurons express the SVCT2 transporter. However, there have not been molecular and kinetic analyses addressing the expression of SVCTs in cortical embryonic neurons. In this work, we confirmed the expression of a SVCT2-like transporter in different regions of the fetal mouse brain and in primary cultures of neurons by RT-PCR. Kinetic analysis of the ascorbic acid uptake demonstrated the presence of two affinity constants, 103 microM and 8 microM. A K(m) of 103 microM corresponds to a similar affinity constant reported for SVCT2, while the K(m) of 8 microM might suggest the expression of a very high affinity transporter for ascorbic acid. Our uptake analyses also suggest that neurons take up dehydroascorbic acid, the oxidized form of vitamin C, through the glucose transporters. We consider that the early expression of SVCTs transporters in neurons is important in the uptake of vitamin C, an essential molecule for the fetal brain physiology. Vitamin C that is found at high concentration in fetal brain may function in preventing oxidative free radical damage, because antioxidant radical enzymes mature only late in the developing brain.

Animals↗
PubMed2001

Influence of pre-fermentative treatment on the fatty acid content of Saccharomyces cerevisiae (M(3)30-9) during alcoholic fermentation of grape must.

The effect of skin maceration and must filtration on the growth and fermentative capacity of one strain of Saccharomyces cerevisiae was studied. Skin maceration increased the fatty acid concentration of the must, thus affecting the lipid composition of the yeast cell membranes. Sterile filtration resulted in a reduction of the fatty acid content of the must extracted during maceration, but increased the fatty acid content of the yeast membranes, thus increasing the fermentative capacity without affecting either growth or cell viability.

Journal Article↗
PubMed2001

Influence of oxygen addition during growth phase on the biosynthesis of lipids in Saccharomyces cerevisiae (M(3)30-9) in enological fermentations.

The fatty acid, phospholipid and sterol composition of one strain of Saccharomyces cerevisiae under different oxygen levels during grape must fermentation was studied. Anaerobiosis partially inhibited yeast growth and resulted in a drop in the unsaturation index of the fatty acids throughout the fermentation, as well as an abnormally low ergosterol/phospholipid ratio. Aeration after 48 h of fermentation in anaerobiosis stimulated growth and increased cellular viability, as well as raised the unsaturation index of fatty acids. Although the ergosterol/phospholipid ratio remained low in the days following the aeration, by the end of the fermentation the value was that considered optimum for the maintenance of membrane functions.

Journal Article↗
PubMed1992

[Maternal attitude to breast feeding and difficulties in the immediate puerperium].

OBJECTIVE: To investigate the attitudes of women who have just given birth towards breast feeding according to their social class and level of education, as well as the problems arising during their stay in hospital, and the possible repercussions the latter might have. DESIGN: Transversal descriptive study, based on random sampling. SITE. The Maternity Unit of the "Marqués de Valdecilla" University Hospital, Santander. PARTICIPANTS: 100 mothers of newborn babies chosen at random amongst those who had given birth vaginally to normal babies after a nine months pregnancy. RESULTS: The results from the questionnaire show that: 35% derived their information on breast feeding from magazines, 25% from the psychoprophylactic obstetrician (PPO), 28% had no information. 60% of the sample took the decision to breast-feed before pregnancy, 21% during the pregnancy, and 6% after the birth. 78% of the children were fully documented at the hospital on: first time at the breast, frequency of feeds, glucose solution supplement. 60% of the mothers evidenced problems with their breasts. On leaving hospital, 83% were breast feeding. CONCLUSIONS: To continue promoting breast feeding and helping mothers not to have so many problems at the beginning, we should use primary health attention, PPO courses and prenatal education as platforms for action, emphasising the importance of preventive care of the breast and breast-feeding technique. Hospitals should incorporate the international recommendations on initial lactation, with subsequent reinforcement during home visits and health centre appointments.

Adult↗
PubMed1990

Alcohol and aldehyde dehydrogenase from Saccharomyces cerevisiae: specific activity and influence on the production of acetic acid, ethanol and higher alcohols in the first 48 h of fermentation of grape must.

The changes in the specific activity of alcohol dehydrogenase (ADH-I and ADH-II) and aldehyde dehydrogenases [AIDH-NADP+ and AIDH-NAD(P)+] from Saccharomyces cerevisiae during the first 48 h of fermentation of grape must were investigated. The biosynthesis of ADH-I and AIDH-NADP+ took place basically during the adaptation of the yeasts to the must (first 4 h), while that of ADH-II occurred immediately after exponential growth (after 12 h). From the products produced by the yeast, only the specific rate of production of ethanol was found to be directly related to the specific activity of ADH-I.

Acetates↗