Moisture retention of glycerin solutions with various concentrations: a comparative study.

Various methods of evaluating a humectant's moisture retention have unique mechanisms. Hence, for designing advanced or efficient ingredients of cosmetic products, a clear understanding of differences among methods is required. The aim of this study was to analyze the moisture-retention capacity of glycerin, a common ingredient in cosmetic products. Specifically, this study applied gravimetric analysis, transepidermal water loss (TEWL) analysis, and differential scanning calorimetry (DSC) to examine the evaporation of glycerin solutions of different concentrations. The results revealed that the moisture-retention capacity of glycerin increased with the glycerin concentration from 0 to 60 wt%, and glycerin at concentration of 60-70 wt% did not exhibit weight change during the evaporation process. When the glycerin concentration exceeded 70 wt%, moisture sorption occurred in the glycerin solution. Furthermore, the results revealed a deviation between the evaporation rates measured using gravimetric analysis and those measured using TEWL analysis. However, normalizing the results of these analyses yielded the relative evaporation rates to water, which were consistent between these two analyses. DSC thermograms further confirmed the consistent results and identified two hydrated water microstructures (nonfreezable water and free water) in the glycerin solutions, which explained why the measured evaporation rate decreased with the glycerin concentration. These findings can be applied to prove the moisture-retention capacity of a humectant in cosmetic products by different measuring methods.

Inotropic and chronotropic actions of Ilex latifolia inhibition of adenosine-5 '-triphosphatases as a possible mechanism.

Ilex latifolia is widely used as an ingredient to prepare traditional beverage drinks in southern China. In fact, various Ilex species have been used in Chinese folk medicine to treat coronary heart diseases. The mode of action is believed to be mediated by their coronary vasodilative effects. In this study, the water extract of the leaves of Ilex latifolia (IK-TP) was shown to increase the contractility and decrease the frequency of contraction in an isolated rat heart perfusion system. IK-TP was found to inhibit Na+/K+-ATPase activities in rat heart sarcolemma, rat brain microsomes and a purified enzyme from porcine cerebral cortex. IK-TP also inhibited Ca2+-dependent ATPase at a similar dose. Following exposure of the isolated rat heart to IK-TP at a dose that produces pronounced cardiac effects, inhibition of Na+/K+-ATPase activity can be readily detected in the heart. This study suggests the presence of ATPase inhibitory compounds in Ilex latifolia with specificities different from that of ouabain.

Inhibition of ATPases by Cleistocalyx operculatus. A possible mechanism for the cardiotonic actions of the herb.

The water extract of the buds of Cleistocalyx operculatus, Roxb. (CO), a herb commonly used as an ingredient for tonic drinks in southern China, was shown to increase the contractility and decrease the frequency of contraction in an isolated rat heart perfusion system. CO was found to inhibit Na+/K(+)-ATPase activities in rat heart sarcolemma, as well as in a purified enzyme from porcine cerebral cortex. CO also inhibited Ca(2+)-dependent ATPase in mouse heart homogenate and in mouse heart sarcoplasmic reticulum at a similar dose. These enzyme inhibitory actions provide a possible explanation for the positive inotropic and negative chronotropic actions of CO on the perfused rat heart. This study suggests the presence of ATPase inhibitory compounds in CO with specificities different from that of ouabain.

Particle size reduction effectively enhances the intestinal health-promotion ability of an orange insoluble fiber in hamsters.

The effects of particle size changes by micronization on the intestinal health-promotion ability of orange insoluble fiber fraction (IFF) were investigated in a hamster model by feeding 3 diets, which contained unmicronized IFF (control), jet-milled IFF, and high-pressure micronized IFF as the sole fiber source in diet. The results showed that the micronization treatments significantly altered the physicochemical properties of insoluble fiber. The consumption of the micronized fibers (6.26 to 11.4 microm) at a level of 50 g/kg diet, especially those prepared by high-pressure micronization, resulted in significant (P < 0.05) improvements in cecal and fecal parameters such as reduced cecal ammonia concentration (-37.1%), increased fecal moisture (164%), and decreased activities of beta-D-glucuronidase (-68.3%) and mucinase (-28.5%) in feces. Both the particle size and treatment were important factors affecting the composition and physiological functions of fibers, and the consumption of micronized fiber might exert favorable effects on improving the intestinal health of hamsters. This study might give some hints for the potential applications of micron technology in food industry and provide opportunities to develop new formulations of fiber-rich functional foods.