Evaluation de l'activité antifongique de deux dérivés et test d'innocuitéin vivo de shampooings à visée antipelliculaire ainsi formulés

Les pellicules, affection dermatologique due essentiellement à la levure Pityrosporum ovale , affectent les deux tiers de la population, d'une manière plus ou moins sévére.
Pour notre part, nous nous sommes attachés à mettre en évidence l'activité antifongique de deux substances couramment utilisées dans des cosmétiques capillaires: la pyrithione-zinc et la piroctone olamine, à plusieurs concentrations. Une fois choisie, la concentration optimale, deux shampooings ont été formulés, afin de déterminer la tolérance cutanée des formes cosmétiques terminées. La tolérance cutanée a étéévaluée par étude profilométrique de contre-empreintes obtenues à partir d'empreintes de peau.
Cette étude nous révèle une supériorité de la piroctone olamine, aussi bien d'un point de vue activité antifongique que d'un point de vue tolérance cutanée.     

Etude expérimental de l'indice de protection de produits antisolaires. Valeur prédictive à l'homme

Après avoir rappelé brièvement le spectre d'action biologique du rayonnement ultraviolet du soleil sur la peau normale et les données theoriques de protection qui en découlent, le caractère prévisionnel de différentes méthodes d'étude in vitro et in vivo des antisolaires est commentéà partir de résultats obtenus en laboratoire sur différents principes actifs (PABA, Eusolex 4360, Giv Tan F), et préparations cosmétiques du commerce.
Les méthodes in vitro , basées sur l'absorption dans l'UV des produits, aboutissent à une protection surévaluée et dans ces conditions à une extrapolation trés aléatoire du pouvoir de protection.
La méthode utilisée in vivo (détermination classique d'un indice de protection) souligne, dans le cadre de la prédiction, le choix de la qualité d'absorption du filtre, de la source UV utilisée, mais aussi de nombreux autres facteurs agissant sur la protection. Dans ces conditions, les résultats obtenus chez le cobaye et l'homme avec des irradiations simulant le spectre solaire, montrent alors une concordance satisfaisante pour les principes actifs étudies. Ces observations sont ensuite commentees par comparaison à d'autres travaux publiés faisant mention d'autre source d'irradiation (spectre de raies) et de méthode de détection (thermométrique en particulier).
Predictive nature of laboratory methods in sunscreen studies     

Quelques composés volatils formés au cours de I'irradiation gamma de I'amidon de maïs

Some Volatile Compounds Formed During Gamma Irradiation of Corn Starch. Acetaldehyde, methanol, acetone, small amounts of methyl formate and various quantities of ethanol were found in ⁶⁰Co irradiated maize starch, using gas chromatography coupled with mass spectrometry. Influences of dose, temperature, atmosphere composition, water and impurities content, were investigated respectively for the first three substances. Irradiation effects were compared to heat treatment effects and concentration changes were followed during storage.     

Etude des mécanismes de formation de quelques produits identifiés après irradiation gamma de l'amidon de maïs

Studies of the Formation Processes of Some Identified Radiolysis Products after Gamma Irradiation of Maize Starch . From the variations in the concentrations of different starch radiolysis products, studied as function of starch water content and of oxygen pressure, it has been possible to suggest different formation processes. The initied break of the C O C linkages as well as the further rearrangement of the radicals formed or their reactions with water and oxygen explain the observed rearrangements. Water generally has a protector effect, which can be interpreted as an inhibition of primary radical transformation. As for oxygen, its fixation on a carbon radical may account for the generally stimulating action of this gas.     

Evaluation des carbonyles formés au cours de I'irradiation gamma de I'amidon de maïs

Evaluation of Carbonyl Compounds Formed During Gamma Irradiation of Maize Starch . Changes in the levels of radioinduced carbonyl compounds were analysed as a function of irradiation conditions (dose, dose rate, temperature, atmosphere), starch properties (water content) and post irradiation treatments (storage, autoclaving). The percentages of identified and unknown carbonyl fractions were respectively 40 and 60 %. The half unknown fraction was linked on the radiodextrins (polysaccharides formed during irradiation of starch).     

Technique de dilution isotopique pour le dosage de quelques produits carbonylés de faible poids moléculaire formés au cours de l'irradiation gamma de l'amidon de maïs marqué

Isotopic Dilution for Quantitative Determination of Some Low Molecular Weight Carbonyl Compounds Formed During Gamma Irradiation of Labelled Maïze U (¹⁴C) Starch . Gamma-induced glycolaldehyde, glyoxal, glyceraldehyde and hydroxymethylfurfural in maïze starch were quantitatively estimated by isotopic dilution from U (¹⁴C) starch. The experimental procedure was described and concentrations of individual compounds expressed as a function of dose (0 to 4.5 Mrad). The highest value was found for glycolaldehyde (9.1 μg/g/Mrad) with a few small traces of hydroxymethylfurfural.     

Identification et dosage des sucres de faible poids moléculaire formés au cours de l'irradiation de l'amidon de maïs

Sugars Formed During Irradiation of Maize Starch. Identification and Determination Sugars of low molecular weight formed during irradiation of maize starch were identified and determined by ion exchanger chromotography. The following sugars were found: one disaccharide (maltose), hexoses (glucose, mannose, galactose, fructose), pentoses (arabinose, xylose, ribose), and one tetrose (erythrose). There remains a slight uncertainty in the cases of mannose and erythrose. The influence of irradation conditions (dosis, atmosphere, temperature), of starch properties (bumidity, impurities, glucosidic bonds), and of storage conditions was examined. By the results it was made possible to propose a hypothesis on the kind of sugar formation and on the role of water in this process, which takes the observed differences into consideration satisfactorily. Irradiation effects have been compared to those given by heating.     

Evolution de quelques caractéristiques des amidons extraits de grains de maïs normal et d'amylomaïs au cours de leur formation,

The Development of Some Characteristics of Starches extracted from Normal Corn and Amylomaize Grains during their Formation. Within the research work on the evolution of corn grains constituents with different amylose contents, during their development, a study has been carried on the starch content of corn grains, amylose content of starch grains, microscopical and submicroscopical aspects of starch grains and their crystalline organization marked by X rays diffraction. The quantity of starch synthetized for one corn grain is stated as all the more important as the amylose content of grain is lower. For amylomaizes, it is pointed out that the determination of amylose content of starch carried on at 2°C leads to higher values than at 20°C. The difference between the results might be ascribed to the presence of a glucidic fraction reacting as amylose and synthetized in a relatively important proportion at the beginning of corn grain formation, and later on becoming diluted with the other amylaceous components. The increasing stability of amylomaize starches when thermically treated might correlate with their amylose content.     

羊毛脂制备羊毛酸的工艺研究

以羊毛脂为原料,在现有的羊毛脂皂化工艺基础上,增加了钙化、醇洗步骤,对钙化、醇洗的影响因素进行了初步探究,并结合气相色谱质谱联用仪对所制羊毛酸脂肪酸组成进行分析。考察了钙化过程中无水氯化钙的添加量、钙化温度、钙化时间对羊毛酸产率的影响,考察了醇洗过程中溶剂类型、醇洗温度、醇洗次数对羊毛酸纯度的影响。最终确定钙化的最优条件为无水氯化钙添加量为理论值的1.2倍、钙化温度50℃、钙化时间1 h,醇洗的最优条件为溶剂为无水乙醇、醇洗温度60℃、醇洗次数4次。在优化的工艺条件下,羊毛酸产率达到82.38%,纯度为84.76%,羊毛酸中支链脂肪酸含量为64.35%。     

Etude de l'acidité formée au cours de l'irradiation gamma de l'amidon de maïs

Study of γ Radioinduced Acidity in Corn Starch. Amounts of radioinduced acids and esters in corn starch have been measured in terms of different conditions of irradiation (dosis, dosis rate, temperature, atmosphere) and of starch characteristics (% water, impurities, kind of glucosidic link) and results have been compared to those given by heat sterilization. Subsequent development of acidity have been checked during the storage at ambient temperature.     

羊毛脂的理化指标及主要成分分析

羊毛脂的理化指标和组成对其使用性能影响较大,因而采用国标等方法对原料羊毛脂的熔点、水分及挥发物含量、灰分含量、酸值、过氧化值、碘值、色度等基本理化指标进行分析,并通过薄层色谱及柱层析对其主要成分进行分析鉴定,采用气质联用色谱对羊毛醇和羊毛酸进行定性定量分析。结果表明：与精制羊毛脂（药典级）相比,原料羊毛脂色泽较深,水分及挥发物含量、灰分含量、碘值与酸值略高;羊毛脂的主要组成成分为脂肪酸酯、羟基酸酯、游离甾醇及多羟基物残留物,分别占羊毛脂总质量的55.14%、25.57%、4.04%和13.15%;原料羊毛脂中甘油三酯未检出;羊毛醇的主要组成为胆甾醇与羊毛甾醇,相对含量分别为44.31%与14.62%,羊毛脂中胆甾醇和羊毛甾醇含量分别为10.41%、3.43%（以全样原料羊毛脂计）;羊毛酸的主要组成为饱和脂肪酸,碳链长度为C13~C27,其中支链脂肪酸相对含量高达62.03%,异构支链脂肪酸相对含量为27.56%,反异构支链脂肪酸相对含量为34.47%。     

Etude de l'aldéhyde glycolique formé au cours de l'irradiation gamma de l'amidon de maïs

Research of Glycolaldehyde Formed During Gamma Irradiation of Maize Starch . During gamma irradiation of maize starch, glycolaldehyde occurs (5,6 μg/g/Mrad, in oxygen). The influence of several parameters has been determined: irradiation conditions (dose, temperature, surrounding gas), stockage temperature and starch characteristics (moisture, impurities). On the other hand, irradition effects were compared to heat treatment effects.     

氧化亚硫酸化羊毛脂皮革加脂剂的制备

羊毛脂乙酰化产物、改性菜油、鱼油和合成牛蹄油的混合物 ,在负载型金属皂的催化下 ,用空气进行氧化 ,温度 80℃ ,时间 4 - 6h ,氧化产物再与焦亚硫酸盐进行亚硫酸化反应 ,能够制备出一种亚硫酸化类羊毛脂加脂剂。该工艺技术路线设计新颖合理 ,工艺方法简便可行 ,是一种绿色化工工艺过程。     

Préparation et caractérisation de produits amylacés polytransformés Partie 2. Caractérisation rhéologique de carboxymethylamidons benzylés

Preparation and Characterization of Polyfunctional Starch Products. Part 2. Rheological Characterization of Benzylated Carboxymethylstarches . “Higy” and “low” viscosity carboxymethylstarches and their benzylated derivatives were rheologically studied. For the shear rates of 3 to 700 sec⁻¹ the rheological behaviour may be described by the power law T = K Dⁿ, from which n depends mainly from the volume occupied by the solvated solute. During benzylation a partial decarboxymethylation and some hydrolysis occured. Carboxymethylstarches treated in the same conditions as for benzylation but without benzylchloride, gave derivatives which were also rheologically characterized for comparison. The benzylated carboxymethylstarches of low viscosity have good sizing properties (paper and textile).     

Contribution à l'étude expérimentale de la séborrhée. Implications éventuelles en cosmétologie

The sebaceous gland is an androgen-dependent structure and a major site for androgen metabolism. Androgens are involved in stimulation of sebaceous secretion in humans. The object of this study is to contribute to the understanding of the role of these hormones and their metabolites in seborrhea and to comment on the activity of certain inhibitors. Methods used are sebaceous secretion and ¹⁴C-lipogenesis in animals, ¹⁴C-testosterone or DHA metabolism in animal and human skin. Our results showed that: – by subcutaneous administration in rats, there was a relative specificity of weak androgens for sebaceous gland stimulation unlike potent androgens.