Modulation of sebum excretion from the follicular reservoir by a dichlorophenyl-imidazoldioxolan

The dichlorophenyl-imidazoldioxolan elubiol is used for skin and hair care in subjects with oily skin or dandruff. A study was conducted in 14 men to evaluate by non-invasive methods the effect of long-term use of elubiol on the sebum output at the skin surface. Measures were made using the Sebumeter SM810 and Sebutapes. Data show a progressive decrease in skin oiliness at the forehead site treated by elubiol compared to the contralateral control site. The function of the follicular reservoir appears to be affected without significant primary change in the sebaceous gland activity.     

Prolonged effects of antidandruff shampoos - time to recurrence of Malassezia ovalis colonization of skin

Most active antidandruff shampoos exhibit a strong activity against the yeast Malassezia ovalis. The present study was undertaken to compare the prolonged antifungal effect of three proprietary shampoos containing either 2% ketoconazole, 1.5% zinc pyrithione or 2.5% selenium sulphide. Superficial squames were harvested from the scalp in the days following a 6-week antifungal shampoo treatment. Counts of yeasts highlighted by a fluorochrome were made using computerized image analysis. Data show the increased duration of yeast reduction for the ketoconazole shampoo over the two other formulations. The lingering effect of ketoconazole is explained by the combination of its antifungal and pharmacokinetic properties.     

Condensed tannins from Lotus corniculatus and Lotus pedunculatus exert different effects on the in vitro rumen degradation of ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) protein

Condensed tannins (CT) or proanthocyanidins (PA), which occur in a restricted range of forages, have the ability to interact with proteins and enzymes and can influence the digestion of plant protein in the rumen. We compared the effects of CT extracts from Lotus corniculatus and pedunculatus on degradation of the principal leaf protein, ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco), by rumen microorganisms. Total soluble leaf protein extracted from white clover (Trifolium repens ) was incubated with fresh rumen fluid from sheep and a range of concentrations of each CT extract. The rate of degradation of the large (LSU) and small subunit (SSU) of Rubisco was quantified by fractionating the proteins in samples taken from in vitro rumen incubations using sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS‐PAGE) and imaging densitometry. To deduce the effects of the CT extracts, experiments were performed in the presence (CT inactive) and absence (CT active) of polyethylene glycol (PEG; MW 3350). The two CT extracts differed markedly in their effects on the degradation of the LSU and SSU of Rubisco. At concentrations of 0.89 and 1.79 mg CT mg ⁻¹ total soluble leaf protein, the CT extract from L pedunculatus was more effective at preventing the degradation of the LSU and SSU by rumen microorganisms than the CT extract from L corniculatus. At a concentration of 1.79 mg CT mg ⁻¹ total soluble leaf protein, the CT extracts from L corniculatus and pedunculatus prevented about 0.75 and 0.83 of the LSU and about 0.69 and 0.86 of the SSU, respectively, from being degraded. Addition of PEG removed the inhibition and almost complete degradation of these proteins occurred, as was the case in incubations without CT extracts. The results of this study suggest that the concentration of CT in the diet and the chemical structure which affects the activity of the CT needs to be considered when assessing the effects of CT on protein metabolism in ruminants. © 1999 Society of Chemical Industry     

葡萄籽多酚提取物的提取工艺研究

以榨过油的酿酒葡萄籽为原料,水为提取溶剂,考虑不同因素对提取效率的影响,如粉碎度、料水比、温度、提取时间、提取次数等,在单因素实验的基础上进行正交实验.分析结果表明,各因素影响效果依次为温度、提取次数、提取时间和料水比,粉碎度对提取效果影响不显著.最终工艺确定为100℃,料水比1：9,提取三次,每次1.5h.所得水溶液浓度约为1mg/mL,经冷冻干燥得葡萄籽多酚提取物粉末,其产率为3.3%.     

芍药属油用植物种质资源及研究进展

在关于芍药属油用植物研究的文献统计分析基础上,结合本课题组的已有研究成果,综述了芍药属油用植物种质资源及牡丹组的研究现状,同时为了全面汇总芍药属油用植物的研究进展,本文介绍目前研究较为有限的芍药组。主要包括芍药属油用植物种质资源简介及分布,芍药属油用植物种籽结实特性、生化成分、活性物质以及含油率,籽油主要理化指标、油脂提取工艺、脂肪酸组成、营养保健功能及所提油脂的加工利用、籽粕化学成分及功能特性。最后总结芍药属油用植物研究现状中存在的问题,并对其应用前景进行了展望。     

Responses of Lotus corniculatus to environmental change. 2. Effect of elevated CO2, temperature and drought on tissue digestion in relation to condensed tannin and carbohydrate accumulation

Clonal plants of three genotypes of Lotus corniculatus (cv Leo) were grown in eight controlled environments under combinations of two temperature regimes, two CO₂ concentrations and two watering regimes. Condensed tannins (proanthocyanidins), in-vitro digestibility, initial rates of gas evolution (as an indicator of the initial rates of fermentation of the substrate), volatile fatty acid evolution, and non-structural carbohydrate (NSC) levels were determined in leaves, stems and roots at full flowering. Under control conditions (average midsummer conditions in the United Kingdom) the total condensed tannin content of leaves varied six-fold between genotypes but condensed tannin contents in stems and roots were similar. Condensed tannin levels were significantly increased in leaves and stems of all three genotypes by doubling the CO₂ concentration while raising the temperature towards the optimum for growth significantly reduced condensed tannin levels. Drought stress significantly reduced condensed tannin levels in leaves and, particularly, in roots. Nutritive value was inversely related to condensed tannin levels in leaves and a negative relationship was observed between condensed tannin concentrations of more than 25–30 g kg⁻¹ dry matter and the initial rates of gas evolution when subjected to in-vitro fermentation with rumen micro-organisms. In leaves, digestibility was significantly increased by drought and by increasing temperature but reduced by high CO₂. In stems, digestibility was significantly increased by drought, but not significantly affected by increasing temperature, or by high CO₂ alone. In roots, digestibility was significantly increased by drought, and decreased by increasing temperature or CO₂. Increasing the growth temperature towards optimum growth reduced the content of NSC in all tissues with the greatest changes occurring in root tissue. Doubling the CO₂ concentration increased NSC levels in leaves and stems with starch content more than doubled under high CO₂ while, in roots, increased levels were only observed in combination with drought stress. There was a linear correlation between condensed tannin concentration and total NSC that was positive for leaves, neutral for stems and negative for roots. The relationship between carbohydrate levels and rates of gas production was negative for leaves and positive for stem and roots. © 1999 Society of Chemical Industry     

Formulation and stability of a novel artificial sebum under conditions of storage and use

Materials in contact with liquids on the human skin surface may dissolve and permeate into skin. Release and permeation of chemicals in contact with skin is often estimated in vitro using artificial skin liquids, although sebum lipids are generally not included in these models. The purposes of this research were to develop a representative artificial sebum that contains the appropriate types of lipids at levels that match human values and quantitatively characterize the model to understand its utility for in vitro testing. Artificial sebum that consisted of 10 lipids at proportions that closely resembled human sebum was characterized using thin layer chromatography under a variety of storage and use conditions (dry and liquid, 4°C and 32°C, with and without vitamin E) for 28 days. Levels of sebum constituents maintained in solution and dry at 4°C were stable through the duration of the test period. Levels of all sebum lipids maintained dry at 32°C were stable in the presence of vitamin E; however, squalene oxidized rapidly in the absence of vitamin E. Liquids on the human skin surface consist of sebum and sweat with minor amounts of cellular debris and intercellular lipid from the stratum corneum. The relative importance of each component for release of chemicals from materials in contact with skin will depend upon the type of material (metal, organic, etc.). A model artificial sebum was formulated and characterized to aid researchers in understanding potential release of chemicals from materials in contact with skin and subsequent partitioning and absorption.     

Expert opinion and review article: The timing of comedone extraction in the treatment of premenstrual acne – a proposed therapeutic approach

The face is the most exposed part of our body, and deterioration of facial appearance, through disease or ageing, causes psychological distress. Acne lesions and subsequent pigmentation changes contribute to the unevenness of skin colour that is detrimental to facial attractiveness and leads to rejection and stigmatization in our society. The purpose of this review is to look at the root causes of premenstrual acne and, for the first time ever, propose that the specific timing of treatment can, at least in part, resolve the acne lesions. We postulate that it is the timing of the manual extraction that matters in resolving premenstrual acne and that the effectiveness of this therapy could be improved. Based on the reviewed evidence, we propose that it is important to remove the comedones at the time of ovulation, prior to the reduction of the size of the sebaceous orifice and epidermal barrier function, to counteract the onset of increased sebum production, prevent blockage of the pores and subsequent bacterial colonization and inflammation. If performed successfully, the extraction may contribute to a reduction in inflamed acne lesions and thus benefit women by increasing their facial attractiveness, well‐being, social function and thereby decrease psychological stress.     

葡萄籽提取物对葵花籽油抗氧化活性的研究

研究葡萄籽提取物对葵花籽油的抗氧化性能,实验证实葡萄籽提取物对油脂氧化有很好的抑制作用。在油脂中葡萄籽提取物的抗氧化性强于Vc、VE,预示其在粮油食品中具有广阔的应用前景。     

On the effects of a plant extract of Orthosiphon stamineus on sebum‐related skin imperfections

Overproduction of sebum is very common and results in an undesirable oily, shiny complexion with enlarged pores. Sebum secretion is basically under the control of 5‐α reductase, and more particularly under that of type 1 isozyme. But it is also highly sensitive to environmental factors such as temperature, humidity and food. Moreover, in Asia, the edicts of a flawless facial skin turn oily skin into a major concern for Asian women. We identified Orthosiphon stamineus leaf extract as an interesting ingredient for reducing the oily appearance of skin thanks to its ability to reduce 5‐α reductase type 1 expression in normal human epidermal keratinocytes in vitro. This was confirmed ex vivo, where Orthosiphon stamineus leaf extract was shown to reduce 5‐α reductase activity as well as the production of squalene, one of the main components of sebum that was used as a tracer of sebum. To evaluate the efficacy of Orthosiphon stamineus leaf extract at reducing sebum‐related skin imperfections in vivo, we performed two different clinical studies, one in France on a panel of Caucasian volunteers and the other one in Thailand on a panel of Asian volunteers. Using instrumental techniques as well as clinical evaluation and self‐evaluation, we could highlight that an O/W cosmetic formula containing 2% of Orthosiphon stamineus leaf extract could visibly reduce the oily appearance of skin as well as the size of pores, thus leading to a significant improvement of complexion evenness and radiance. Overall, the results obtained were better than those observed with the same formula containing 1% of zinc gluconate, an ingredient frequently used in oily skin care products.     

正交试验法优化莲子壳中原花青素的提取工艺

试验优选了莲子壳中原花青素的最佳提取工艺。以原花青素的提取率为指标,采用单因素试验和正交试验法,考察乙醇浓度、料液比、提取温度、提取时间4因素对原花青素提取率的影响,优选其最佳提取条件。结果表明,优选出的最佳提取工艺为:提取溶剂50%乙醇,料液比1∶10(g/m L),提取温度65℃,提取时间3 h。该提取工艺操作简单,稳定性好,适用于工业化生产。     

Age‐related changes in skin barrier function – Quantitative evaluation of 150 female subjects

The protection against water loss and the prevention of substances and bacteria penetrating into the body rank as the most important functions of the skin. This so‐called ‘skin barrier function’ is the natural frontier between the inner organism and the environment, and is primarily formed by the epidermis. An impairment of the skin barrier function is often found in diseased and damaged skin. An influence of ageing on skin barrier function is widely accepted, but has not been conclusively evaluated yet. Therefore, the aim of this clinical study was to assess the potential influence of ageing on skin barrier function, including transepidermal water loss (TEWL), stratum corneum hydration, sebum content and pH value. One hundred and fifty healthy women aged 18–80, divided into five age groups with 30 subjects each, were evaluated in this study. TEWL, hydration level, sebum secretion and pH value of hydro‐lipid acid film were measured with worldwide acknowledged biophysical measuring methods at cheek, neck, décolleté, volar forearm and dorsum of hand. Whereas TEWL and stratum corneum hydration showed only very low correlation with subject's age, the sebum production decreased significantly with age, resulting in the lowest skin surface lipids levels measured in subjects older than 70 years. The highest skin surface pH was measured in subjects between 50 and 60 years, whereas the eldest age group had the lowest mean pH. The dorsum of the hand was the location with the highest TEWL and lowest stratum corneum hydration in all age groups. The results show that only some parameters related to skin barrier function are influenced by ageing. Whereas sebum production decreases significantly over lifetime and skin surface pH is significantly increased in menopausal woman, TEWL and stratum corneum hydration show only minor variations with ageing.     

Addition of grape seed extract and bearberry to porcine diets: Influence on quality attributes of raw and cooked pork

The effect of supplementation of pig diets with grape seed extract (GSE) (100, 300, 700 mg/kg feed) and bearberry (BB) (100, 300, 700 mg/kg feed) for 56 days pre-slaughter, on the oxidative stability and quality of raw and cooked M. longissimus dorsi (LD) was examined. Susceptibility of porcine liver, kidney and heart tissue homogenates to iron-induced (1 mM FeSO₄) lipid oxidation was also investigated. In raw LD steaks, stored in modified atmosphere packs (75% O₂:25% CO₂) (MAP) for up to 16 days at 4 °C, surface lightness (CIE ‘L’ value), redness (CIE ‘a’ value), lipid stability (TBARS, mg MDA (malondialdehyde)/kg muscle) and pH were not significantly affected by supplemental GSE or BB. Similarly, the oxidative stability and sensory properties of cooked LD steaks, stored in MAP (70% N₂:30% CO₂), for up to 28 days at 4 °C, were not enhanced by dietary GSE or BB. Iron-induced lipid oxidation increased in liver, kidney and heart tissue homogenates over the 24 h storage period and susceptibility to oxidation followed the order: liver > heart > kidney. Dietary GSE or BB did not significantly reduce lipid oxidation in tissue homogenates. Potential reasons for the lack of efficacy of supplemental GSE and BB on pork quality were explored.     

杏仁种皮中多酚类物质的提取研究

杏仁种皮中含有膳食纤维、多酚类物质和黄酮类物质等。采用乙醇溶剂提取杏仁种皮中的多酚类物质,在单因素的基础上,通过正交试验确定最佳提取工艺条件。最佳提取工艺条件为：乙醇体积浓度50%、提取温度80℃、提取时间1 h、料液比1 g∶15 mL,总多酚提取率达到90.35%。     

Alteration on phenolic acids and the appearance of lotus (Nelumbo nucifera Gaertn) seeds dealt with antistaling agents during storage

This study evaluated the preservation effectiveness of selected antistaling agents on lotus seeds (Nelumbo nucifera Gaertn) status and the alteration of phenolic acids during their storage. Ascorbic acid (AA), benzoic acid (BA), sodium hydrogen sulfite (SHS), BA+ AA and SHS+ AA were identified as effective to keep lotus seeds fresh with the order of SHS+ AA > BA+ AA > AA > SHS > BA in terms of general performance on not-browning degree, microorganism contamination status, sensory evaluation, and the protection of polyphenols against being oxidized. The polyphenols determined by HPLC and HPLC-MS in lotus seeds were mainly gallic, chlorogenic, gentisic, caffeic, cinnamic, p-coumaric, ferulic, rosmarinic, and salicylic acids. Chlorogenic, gentisic, and caffeic acids were the main phenolic acids correlated with oxidative browning. SHS+ AA was found on inhibiting chlorogenic acid oxidized (p < 0.05) as well as SHS or AA did. BA+ AA also had protective effect on all these three phenolics. The increment of gallic, caffeic, chlorogenic, and p-coumaric acids at the beginning of storage, which was from the hydrolyzation of glycosides promoted by BA, had accordance with the deteriorate sensory of lotus seeds and led to worse anti-browning effect. Gallic acid was found to be relevant to the degree of microorganism contamination. The stronger antibacterial capacity antistaling agents had, the later regeneration of gallic acid appeared. In conclusion, the selected antistaling agents had different preservation effectiveness, which would synchronously indicate alteration of relevant phenolic acids profiles of lotus seed during storage.     

葡萄籽提取物抗氧化功能的实验研究

目的研究葡萄籽提取物的抗氧化功能。方法以SPF级雄性昆明种小鼠为实验动物,根据小鼠体重随机分为5组,每组10只,分别是空白组、模型组和低、中、高3个剂量组,空白组和模型组每天经口给予溶剂植物油,剂量组每天经口给予葡萄籽提取物,连续灌胃30 d,取血测抗氧化酶活性。此后除空白对照外,各组射线全身一次性照射5～8 Gy 60Coγ,照射后第4天处死动物,取肝组织测过氧脂质含量和抗氧化酶活性,比较各剂量组与模型组的差别。结果经口给予小鼠葡萄籽提取物30 d,高、中剂量组小鼠血中超氧化物歧化酶(SOD)活性,以及高剂量组小鼠血中谷胱甘肽过氧化物酶(GSH-Px)和肝组织中GSH-Px、SOD活性均明显高于模型组,各剂量组小鼠肝中丙二醛(MDA)水平均明显低于模型组。结论葡萄籽提取物有降脂质过氧化的作用,有抗氧化功能。     

莲壳膳食纤维微波-双酶协同提取工艺优化

以莲子壳为原料,采用微波-双酶协同提取莲壳膳食纤维,在单因素试验结果的基础上,进行正交试验,研究莲子壳筛目数、料液比、木瓜蛋白酶和糖化酶用量及提取时间对莲壳膳食纤维提取工艺的影响。结果表明:其最佳提取工艺条件为莲壳筛目数60目,液料比201(mL/g),木瓜蛋白酶加入量3%,微波协同木瓜蛋白酶酶解提取时间为6×20s(提取6次,每次20s,间隔2min),糖化酶用量4%,微波协同糖化酶提取时间8×20s(提取8次,每次20s,间隔2min),该条件下莲壳膳食纤维提取率为72.36%。与双酶提取法相比,微波-双酶协同提取法可缩短70%的时间,提取率提高82.87%。