Moisturizing effect of cosmetic formulations containing Aloe vera extract in different concentrations assessed by skin bioengineering techniques Susi Elaine Dal'Belo, Lorena Rigo Gaspar and Patrícia Maria Berardo Gonçalves Maia Campos Article first published online: 5 OCT 2006DOI: 10.1111/j.0909-752X.2006.00155.x

Aloe vera leaf gel: a review update T Reynoldsa, A.C Dweckb doi:10.1016/S0378-8741(99)00085-9

Abstract Research since the 1986 review has largely upheld the therapeutic claims made in the earlier papers and indeed extended them into other areas. Treatment of inflammation is still the key effect for most types of healing but it is now realized that this is a complex process and that many of its constituent processes may be addressed in different ways by different gel components. A common theme running though much recent research is the immunomodulatory properties of the gel polysaccharides, especially the acetylated mannans from Aloe vera, which are now a proprietary substance covered by many patents. There have also been, however, persistent reports of active glycoprotein fractions from both Aloe vera and Aloe arborescens. There are also cautionary investigations warning of possible allergic effects on some patients. Reports also describe antidiabetic, anticancer and antibiotic activities, so we may expect to see a widening use of aloe gel. Several reputable suppliers produce a stabilized aloe gel for use as itself or in formulations and there may be moves towards isolating and eventually providing verified active ingredients in dosable quantities

Composition and Applications of Aloe vera Leaf Gel Josias H. Hamman Molecules 2008, 13(8), 1599-1616; doi:10.3390/molecules13081599

Abstract Many of the health benefits associated with Aloe vera have been attributed to the polysaccharides contained in the gel of the leaves. These biological activities include promotion of wound healing, antifungal activity, hypoglycemic or antidiabetic effects antiinflammatory, anticancer, immunomodulatory and gastroprotective properties. While the known biological activities of A. vera will be briefly discussed, it is the aim of this review to further highlight recently discovered effects and applications of the leaf gel. These effects include the potential of whole leaf or inner fillet gel liquid preparations of A. vera to enhance the intestinal absorption and bioavailability of co-administered compounds as well as enhancement of skin permeation. In addition, important pharmaceutical applications such as the use of the dried A. vera gel powder as an excipient in sustained release pharmaceutical dosage forms will be outlined.

Tyrosinase Inhibitory Activity of Cucumber Compounds:  Enzymes Responsible for Browning in Cucumber Fernando Gandía-Herrero , Mercedes Jiménez , Juana Cabanes , Francisco García-Carmona , and Josefa Escribano * Departamento de Bioquímica y Biología Molecular A, Unidad Docente de Biología, Facultad de Veterinaria, Universidad de Murcia, E-30100 Espinardo, Murcia, Spain

Abstract The inhibition of mushroom tyrosinase by cucumber extracts was evaluated. The inhibitory effect was measured by both polarographic and spectrophotometric methods. The commercial aldehyde, trans,cis-2,6-nonadienal, described as a major volatile compound of cucumber, was characterized as a noncompetitive inhibitor against 4-tert-butylcatechol oxidation by mushroom tyrosinase. The KI obtained was 3.4 mM. Polyphenol oxidase (PPO) activity was not detected in cucumber skin extracts. However, the presence of PPO was revealed by Western blot; a single band was found with a Mr of 53 kDa. These results support the assumption that the enzyme PPO is present in the cucumber skin, but its activity is inhibited. Peroxidase (PO) was also found in cucumber skin extracts. This enzyme was detected in the soluble fraction but not in the membrane fraction. The kinetic characterization of PO was carried out. Native isoelectric focusing revealed several acidic PO isoenzymes with a pI in the range between 5 and 6, a basic isoenzyme, and one principal neutral isoenzyme of pI = 7.2.

Phytochemical and therapeutic potential of cucumber Pulok K. Mukherjeea, Neelesh K. Nemaa, Niladri Maitya, Birendra K. Sarkarb* doi:10.1016/j.fitote.2012.10.003

THE B VITAMINS IN HONEY1GEORGE KITZES, H. A. SCHUETTE, AND G. A. ELVEHJEM Departments of Chemistry ana Biochemistry, University of Wisconsin, Madison(Eeceived for publication March 25, 1943) Honey is a widely used food an undoubtedly due to itssweetness, pleasant taste and aroma. Since honey is a naturalsubstance and is food for the honeybee, there has been muchspeculation as to its value in the nutrition of man. Honey isprepared from the nectar of flowers by worker bees and storedin the honeycomb. Although honey is derived primarily fromnectaries of flowers, we cannot overlook the part the honeybeeplays in storing the nectar in the hive and in processing it toits final form. Thus honey should be considered the productof the bee processed from a plant product.The analysis of honey has shown that it consists of approximately 75-80% sugar, mainly invert sugar, which is a conversion product of sucrose.

Schuette et al. ( '32, '37, '38, '39)have shown the presence of mineral elements in honey. Notableamong these are iron, copper, sodium, potassium, manganese,calcium, magnesium, and phosphorus, all of which have beenshown to be essential to good nutrition of animals. Since honeyis basically derived from the flower and moreover is a food forthe bee, much speculation has arisen as to its vitamin content,especially because great emphasis has been placed on the importance of vitamins in human nutrition. It seems that thisproblem has interested workers for two decades, many ofwhom have reported the absence of vitamins A, B, C, D, and E1Published with the approval of the Director of the Wisconsin Agricultural Experiment Station. Supported in part by a grant from the American Honey Institute.The authors are indebted to Dr. Frank M. Strong for valuable suggestions regarding the microbiological assays in honey.

These results may be interpreted in the light of themethods employed, which have been much improved in recentyears.Recently chemical determinations of vitamin C in honeyhave been made by Griebel ('38). He reported 160-280 mg.ascorbic acid per 100 gm. of mint honey and 7-22 mg. per 100gm. of other honeys. Griebel and Hess ( '39) identified thestrong reducing substance in thyme and mint honeys as ascorbic acid. They reported 311.2 mg. and 102.6 mg. of thisvitamin per 100 gm. of the respective honeys. Buckwheathoneys contained from 7.36-18.6 mg. ascorbic acid per 100 gm.They (Griebel and Hess, '40) determined also the ascorbicacid content of the nectar of the above plants. It was shownthat there is a considerable loss of vitamin C when nectar isconverted into honey. Schuette and Kaye ( '42) investigateda series of honeys and found 0.55-20.9 mg. of vitamin C per100 gm. The degree of destruction of vitamin C in honey wasalso studied. It was noted that there was a decrease in thetotal ascorbic acid content of honey after pure ascorbic acidwas added. The loss was greatly increased in the honeys placedin diffused light.Hay dak and Palmer ( '42 a) reported the vitamin contentof honeys of varied nectar source and origin. They reportedthe following values per 100 gm. of honey : thiamine,2.1-9.1 Mg-; riboflavin, 35-145 Mg-; pyridoxine, 210-480 Mg.;pantothenic acid, 25-192 Mg.; nicotinic acid, 4-94 mg. ; ascorbicacid, 0.6-5.4 mg.

The authors of this paper will attempt to give a clear picture of the vitamins in honey obtained by the improvedmethods of vitamin assay. These include the more recentmichrochemical and microbiological methods, some of whichhave been modified in the University of Wisconsin. Preliminary investigations did not reveal the presence of the fat-soluble vitamins ; therefore only the contents of water-solublevitamins were determined. Together with numerous samplesof honey we have analyzed pollen and royal jelly, two naturalsubstances also serving as food for bees Riboflavin was determined by the microbiological methodof Snell and Strong ( '39). Preparation of the sample was asfollows : 25 gm. of honey were diluted to 75 ml. with distilledwater and autoclaved for 15 minutes at 15 pounds pressure.The use of acid was avoided for the reasons explained for thenicotinic assay. Enzyme digestion with clarase did not alterthe value significantly. It should be mentioned that the naturalpH range of honey is 4-5 ; therefore the honey dilution wasacid during the autoclaving, thereby reducing any possibledestruction of the riboflavin. Ether extraction of the honeydilution did not remove any stimulatory or inhibitorysubstances.Thiamine was determined by the Hennessy-Cerecedo thio-chrome method as modified by the Research Corporation Committee on the Thiochrome Method (Hennessy, '42).

A Colemanphotofluorometer was used to measure the fluorescence of thethiochrome produced by the oxidation of the thiamine. Thisinstrument can accurately determine 0.02 pg- of thiamine.Recovery of added thiamine ranged from 85% to 105%. Valuesare expressed in micrograms of thiamine-hydrochloride.Pyridoxine was determined by the microbiological methodof Atkin, Schultz, Williams, and Frey ('43). In this methodthe response of a strain of yeast to pyridoxine is measuredby turbidity readings. The range of sensitivity of the assayis 5 to 40 mpg. Enzyme digestion was used to release any boundpyridoxine. Recovery of added pyridoxine ranged from 95%to 105%. Values are expressed in micrograms of pyridoxine-hydrochloride per 100 gm.Biotin was determined by the microbiological method ofSnell, Eakin, and Williams ('40), using yeast and measuringthe growth of the organism by turbidity readings. The assayswere conducted by Miss Josephine Gardner of the Biochemistry Department of the University of Wisconsin.Folie acid was determined by the method of Mitchell andSnell ('41), using the streptococcus lactis organism. The assays were conducted by Mr. T. D. Luckey of the BiochemistryDepartment of the University of 7isconsin.

The folie acid values are expressed in this paper as micrograms of folie acidbased on a solubilized liver standard with a potency of 40,000.The samples of pollen which were analyzed were obtainedfrom Professor Farrar of the Department of Economic Entomology of the University of Wisconsin. One sample ofpollen was a mixture from an area around Madison, Wisconsin. The other sample was a mixture of pollen from BatonRouge, Louisiana. The sample of royal jelly was obtained ina dry form from Dr. H. B. Parks of the Texas AgriculturalExperiment Station.

RESULTS AND DISCUSSION

Table 1 gives the results of analyses of forty samples ofhoneys from different regions of the United States. Althoughthe source of the honey is also listed, it is understood thathoney is usually a mixture of nectars. The floral source listed,however, is the predominant one. An examination of the values obtained for the five members of the B-complex showedgreat variation among the samples. The greatest variationwas in the nicotinic acid content. In one instance, a sampleof honey contained nine times as much nicotinic acid as another. The least variation occurred in -the thiamine and pyridoxinevalues, but even here the variation was as much asfivefold. An attempt was made to correlate the vitamin content with floral source, origin, and color-grade.This provedfruitless for we did not have a sufficiently large number ofsamples of honey of one locality to enable us to say that oneset of data is typical of that source. The wide variation ofthe vitamin contents precluded any attempt to correlate thevalues with the color-grade of the honeys.

Table 2 presents a summary of the vitamin content of thehoneys examined. It also shows the differences in the vitamincontent of the old honeys as compared with the new samples.In the course of the investigation for pantothenic acid, it became apparent that the pantothenic acid values for a largenumber of honeys were lower than those of the rest. It wasfound that the group of honeys that had been obtained from the Chemistry Department contained 50% less pantothenicacid than those received from various beekeepers. The formerwere of the crops of 1935-1939 and had been stored in a darkcloset at room temperature. The honeys obtained this yearwere of the crops of 1940-1942. Many of these samples werereceived in the comb; others had been extracted before shipment. The difference in the pantothenic acid content of thesetwo groups may be explained by the fact that this vitamin isunstable in an acid solution. Honey is naturally acid, havinga pH range of 4-5. This acidity is not very great, but any pantothenic acid that might be in the honey could be destroyedslowly over a period of years. This is of little significance tothe beekeeper or the housewife who do not keep honey for longperiods of time.A few honey samples were analyzed for their biotin andfolie acid content, two new members of the B-complex whoseimportance in nutrition is being investigated. Traces of biotinand folie acid wore found, with the average values of 0.066 Mg.and 3 Mg.per 100 gm., respectively. Since the amounts foundwere very small as compared to other foods, we did not examinemany honeys.

Table 3 presents a comparison of the vitamin content of thesamples of honey of the years 1940-1942 with pollen and royaljelly. It may be noted that the royal jelly, a milky-white sub-stance secreted by the worker bee is unusually high in pantothenicacid and biotin. This may be related to the rapid metabolism in the young bee larvae which depend on this substancefor sustenance the first 3 days after emergence from the egg.Comparison of the vitamin content of pollen with that of honeyrevealed that in general pollen was a hundred times richer inthe B vitamins than honey. This suggested that the vitaminsin the honey may be due partially to the pollen present in eachsample. All natural honeys contain a certain amount of pollen,which at times is very small in quantity. Haydak and Palmer('42a) have found that a commercial process of clarifying honey reduces the vitamin contents 33-50% of the originalvalues. When we filtered diluted honey, through Whatmanno. 40 filter paper subsequent to its preparation for assay, wefound that the riboflavin content was reduced 40% and the nicotinicacid values 25%. It is suggested that the large variationin the vitamin content of the honeys may be due in part to thevariable amount of pollen present.The values reported in this publication compare favorablywith those of other workers. Pearson ( '42) reports an average value of 30.3 ig. of pantothenic acid per gram of pollenand 511 pg. per gram (dry weight) of royal jelly. Cheldelinand Williams ( '42) have analyzed royal jelly for the vitaminsof the B complex. We find that our results agree very wellwith those of the Texas workers. Haydak and Palmer ('42b)report that chemical determinations did not show even tracesof pyridoxine either in bee bread or royal jelly. The valuesthey obtained for the amount of nicotinic acid and pyridoxinefound in honey are many times higher than our results. Thediscrepancy is so great that it is believed to be due to themethods of analyses employed. It is significant to note thatHaydak and Palmer used chemical methods for both the nicotinic acid and pyridoxine determinations. It is probable thatthe treatment of the honey sample necessary to free the vitamins gave rise to interfering substances.

SUMMARY Microchemical and microbiological determinations showedthe presence in honey of thiamine, riboflavin, nicotinic acid,pantothenic acid, pyridoxine, biotin, and folie acid. The variation among samples was very large, due perhaps to the sourceof the honey and the number of pollen grains present. Comparison of new and aged honeys revealed a decrease in thepantothenic acid content of the latter. Pollen and royal jellyhave also been assayed for these vitamins and have been foundto be good sources of the B-complex. Royal jelly is very richin biotin and pantothenic acid, which may be significant in themetabolism of the young bee.

LITERATURECITED ATKIN, L., A. S. SCHULTZ,W. L. WILLIAMSANDC. N. FREY 1943 Yeast micro biological method for the determination of pyridoxine. Ind. and Eng. Chem. (anal.), vol. 15, p. 141. CHELDELIN,V. H., ANDR. J. WILLIAMS 1942 The B vitamin content of foods. The University of Texas Publication No. 4237, p. 105. GRIEBELC. 1938 Vitamin C-enthaltende Honige. Ztschr. Untersuch. Lebensm., vol. 75, p. 417. GBIEBEL,C., ANDG. HESS 1939 Vitamin C-enthaltende Honige. Ztschr. Unter such. Lebensm., vol. 78, p. 308. 1940 Der C-Vitamingehalt des Blutennecktars bestimmter Labiaten. Ztschr. Untersuch. Lebensm., vol. 79, p. 168. HAYDAK,M. H., ANDL. S. PALMER 1942 a Vitamin content of honeys. 'J. Nutrition, vol. 23, p. 581. 1942 b Royal jelly and bee bread as sources of vitamins B C, nicotinic acid and pantothenic acid. J. Econ. Entom., vol. 35, p. 319. HENNESSY,D. J. 1942 The determination of thiamin in cereal products. "Cereal Chemists Bull. ' ', vol. 2. Downloaded from jn.nutrition.org by guest on December 13, 2014 250 GEORGE KITZES AND OTHERS SCHUETTE,H. A., ANDD. J. HuENiNK 1937 Mineral constituents of honey. II. Phosphorus, calcium, magnesium. Food Research, vol. 2, p. 529. SCHUETTE,H. A., ANDF. KATE 1942 Master's Thesis. Univ. Wisconsin. Unpublished. SCHUETTE,H. A., AND KATHOKAREMY 1932 Degree of pigmentation and its probable relationship to the mineral constituents of honey. J. Am. Chem. Soe., vol. 54, p. 2909. SCHUETTE,H. A., ANDR. E. TRILLER 1938 Mineral constituents of honey. III. Sulfur and chlorine. Food Research, vol. 3, p. 543. SCHUETTE,H. A., ANDW. W. WOESSNER 1939 Mineral constituents of honey. IV. Sodium and potassium. Food Research, vol. 4, p. 349. SNELL, E. E., R. E. EAKIN ANDR. J. WILLIAMS 1940 A microbiological method for the determination of biotin. J. Am. Chem. Soc., vol. 62, p. 175. SNELL,E. E., ANDF. M. STRONO 1939 A microbiological assay for riboflavin. J. Ind. Eng. Chem. (anal.), vol. 11, p. 346. SNELL, E. E., ANDL. D. WRIGHT 1941 A microbiological method for the deter mination of nicotinic acid. J. Biol. Chem., vol. 139, p. 625. STRONG,F. M., R. E. FEENET ANDA. EARLE 1941 Microbiological assay for pantothenic acid. J. Ind. Eng. Chem. (anal.), vol. 13, p. 566.