EFFECTS OF LONG-TERM ORAL ADMINISTRATION OF GREEN TEA CULTIVATED IN DIFFERENT DISTRICTS IN JAPAN ON BODY WEIGHT, BLOOD LIPID AND GLUCOSE LEVELS ON db/db MICE

Previous research using short‐term animal experiments has indicated that oral administration of green tea can suppress elevation of blood sugar. However, few data are available on the antihyperglycemia effect of green tea in long‐term experiments. In this study, effects of long‐term (up to 16 weeks) administration of green tea preparations on body weight, blood sugar and lipid content of db/db and db/+m mice were examined. Preparations were prepared by the same procedure from tea leaves cultivated in different districts in Japan. Significant differences (P < 0.05) were observed in the blood parameters and body weight between control and green tea groups of db/db mice. In the case of normal mice, however, no significant difference was observed. In addition, the response to the administration of green tea depended on the source and composition of tea leaves.     

A line-scanning semi-confocal multi-photon fluorescence microscope with a simultaneous broadband spectral acquisition and its application to the study of the thylakoid membrane of a cyanobacterium Anabaena PCC7120

We describe the construction and characterization of a laser‐line‐scanning microscope capable of detection of broad fluorescence spectra with a resolution of 1 nm. A near‐infrared femtosecond pulse train at 800 nm was illuminated on a line (one lateral axis, denoted as X axis) in a specimen by a resonant scanning mirror oscillating at 7.9 kHz, and total multi‐photon–induced fluorescence from the linear region was focused on the slit of an imaging polychromator. An electron‐multiplying CCD camera was used to resolve fluorescence of different colours at different horizontal pixels and fluorescence of different spatial positions in a specimen at different vertical pixels. Scanning on the other two axes (Y and Z) was achieved by a closed‐loop controlled sample scanning stage and a piezo‐driven objective actuator. The full widths at half maximum of the point‐spread function of the system were estimated to be 0.39–0.40, 0.33 and 0.56–0.59 μm for the X (lateral axis along the line‐scan), Y (the other lateral axis) and Z axes (the axial direction), respectively, at fluorescence wavelengths between 644 and 690 nm. A biological application of this microscope was demonstrated in a study of the sub‐cellular fluorescence spectra of thylakoid membranes in a cyanobacterium, Anabaena PCC7120. It was found that the fluorescence intensity ratio between chlorophyll molecules mainly of photosystem II and phycobilin molecules of phycobilisome (chlorophyll/phycobilin), in the thylakoid membranes, became lower as one probed deeper inside the cells. This was attributable not to position dependence of re‐absorption or scattering effects, but to an intrinsic change in the local physiological state of the thylakoid membrane, with the help of a transmission spectral measurement of sub‐cellular domains. The efficiency of the new line‐scanning spectromicroscope was estimated in comparison with our own point‐by‐point scanning spectromicroscope. Under typical conditions of observing cyanobacterial cells, the total exposure time became shorter by about 50 times for a constant excitation density. The improvement factor was proportional to the length of the line‐scanned region, as expected.     

Thermal Degradation of Flavor Enhancers, Inosine 5'-monophosphate, and Guanosine 5'-monophosphate in Aqueous Solution

The mechanism of thermal degradation of inosine 5′-monophosphate (IMP) and guanosine (GMP) was investigated kinetically in aqueous solution as a function of pH and temperature. The degradation of IMP and GMP followed first order kinetics. The rate constants were considerably affected by pH and temperature. The half-life times at 100°C were: IMP, 8.7 hr (pH 4.0), 13.1 hr (pH 7.0), 46.2 hr (pH 9.0); GMP, 6.4 hr (pH 4.0), 8.2 hr (pH 7.0), 38.5 hr (pH 9.0). These times were shortened to about one-third by raising the temperature 10°C. The predominant degradation products were nucleosides and phosphoric acid, indicating that the main reaction of the thermal degradation was the hydrolysis of the phosphoric ester bond in the nucleotides.     

Oxidative Deterioration in Dried Fish Model Systems Assessed by Solid Sample Fluorescence Spectrophotometry

Oxidative deterioration of fish model systems stored at 25°C in the dark was investigated. Peroxide and TBA values and fluorescence intensities of organic solvent extracts did not correlate well with the extent of lipid oxidation determined by oxygen absorption. However, two types of organic solvent-insoluble fluorescences (I: ex. 370 nm, em. 460 nm; II: ex. 450 nm, em. 500 nm) were observed in fish meats by solid sample spectrofluorometry. Fluorescence II showed a high positive correlation with oxygen absorption. Measurement of protein-bound fluorescence could be useful for assessment of oxidative deterioration in freeze-dried fish muscle and other lipid foods.     

具有O／W／O型多重乳化体系之高效防晒品

近年来,由紫外线(UV)引起的肌肤伤害已逐渐被广泛认知,防晒产品的使用也因此逐渐增加.为了防御人体肌肤受到伤害,开发了一系列高效防护UVA/UVB的防晒产品,既便在高温高湿环境下使用,肤感依然良好.为达成对UVA/UVB的高效防护并兼具有舒适的肤感,有必要将作为紫外线吸收剂的无机颗粒均一分散在产品中.因此,开发出一个油包水包油(O/W/O)型多重乳化体系.在该体系内,疏水性无机微颗粒被分散于内层油相和外层油相中.涂抹于肌肤时,观察到微孔(未被无机颗粒覆盖的区域)于皮肤上的数量明显少于大多数使用W/O型乳化体系之防晒产品.这个O/W/O型多重乳化体系,不需在紫外线吸收剂中增加无机颗粒的含量,紫外线(UV)的防护效果就能增强;因此,能被用来制备兼具高效紫外线防护与良好肤感的防晒产品.描述的O/W/O型多重乳化体系,微孔少,可提供优越的UVA/UVB防护,防御人体肌肤受到伤害.     

Limonoids and Flavonoids in Juices of Oroblanco and Melogold Grapefruit Hybrids

Oroblanco and Melogold are hybrids obtained from pummelo and grapefruit. Limonoids and flavonoids in both juices were analyzed. Oroblanco and Melogold juices contained low concentrations of limonoid glucosides, an average of 99 and 59 ppm, respectively. However, they contained relatively high concentrations of bitter limonoid aglycones, limonin and nomilin, at levels above the limonin bitterness threshold. For comparison, limonoid glucosides in juices of grapefruit, another pummelo hybrid, were also analyzed. Limonin glucoside was the major limonoid glucoside in all juices analyzed. Nomilin glucoside and nomilinic acid glucosides were also present. Oroblanco and Melogold juices contained bitter flavonoids normally found in grapefruit and pummelo including naringin, neohesperidin and poncerin in total amount of 440 ppm in Oroblanco juice and 495 ppm in Melogold juice. They also contained several other nonbitter flavonoids found in grapefruit.     

广州城乡老年人住宅夏季室内环境调查与实测

广州夏季高温高湿,基于广州城乡老年人的室内环境差异,通过问卷调查了解了116 名广州城乡老年人的室内居住环境, 并对5 户典型城市及5 户典型农村65 岁以上居民住宅的夏季室内环境进行了对比实测研究,测量每户住宅的客厅,卧室和卫 生间的温度、相对湿度及CO2、CO、PM2.5、挥发性有机物浓度。研究表明,广州农村住户夏季主要使用风扇降温,仅有约三 分之一住户同时使用空调,而城市住户均使用空调,大部分住户同时使用风扇;广州农村住户夏季室内平均空气温度比城市住 户低0.8 ℃,平均相对湿度比城市住户高21.6%;通风较差的住户室内CO2 浓度相对较高,所有实测城市及农村住户的CO、 PM2.5 的浓度都低于国家标准规定的极限值;广州城市住户的室内外PM2.5 浓度及室内总挥发性有机物的浓度总体高于农村住户。 广州农村老年人住宅应加强防潮处理,城市老年人住宅应加强通风换气,优选环保家具。     

Polygalacturonase Content of Dates and Its Relation to Maturity and Softness

SUMMARY: The changes in polygalacturonase (PG) activity during ripening and the relationship between its activity and the quality of Deglet Noor dates were studied. PG activity, which was virtually absent at the green stage, began to develop as maturity progressed. The greatest part of the development occurred at the late red stage and activity reached its maximum when the fruits commenced softening. Among the four grades of dates used in this study the activity was highest with natural, followed by waxy, number 1 dry and number 2 dry grades. The dates contained 0.9-1.3 units of PG per g of fresh tissue. The results of chemical and physical analyses related to the texture are also reported.