Aloe vera has been recognized and coveted as a medicinal plant for thousands of years. More recently, through modern scientific research, the active ingredients, and their underlying mechanisms of action, responsible for Aloe vera\'s many beneficial medicinal activities have been uncovered. In 1989 Acemannan, a long chain, mannose rich, polysaccharide was identified as the primary active ingredient in Aloe vera inner leaf gel.1, 2 Since then more than 3,690 scientific articles have been published worldwide exploring the various medicinal activities of Aloe vera and Acemannan preparations. One important outcome of these studies was the recognition that the medicinal activities of Aloe vera are critically dependent upon the methods of preparation and that many of the commonly used methods of preparation destroy or inactivate Acemannan.3, 4 As a result, many early scientific studies were conducted using suboptimal preparations of Acemannan.
This broad range of Acemannan activity used in early scientific studies led to conflicting scientific reports, which, in turn, led to many myths and misconceptions about the true medical benefits of Aloe vera inner leaf gel and its major active ingredient Acemannan. Currently there is no standardized method to measure Acemannan activity, as a result, there remains a broad range of Acemannan quality and activity in products on the market today.5, 6 This short article attempts to address some of the more common myths and misconceptions about Aloe vera.
Myth: All Aloe is the same
False. We now know that growing conditions and age of the plant dramatically affect the amount of Acemannan in inner leaf gel. We also know that methods used to process inner leaf gel dramatically affect the amount and quality of Acemannan in Aloe preparations. For example, it is now known that high heat, dramatic changes in pH, and alcohol extraction, all of which have been commonly used in the preparation of Aloe in the past, inactivate and or destroy Acemannan.3 Adding to the problem is when the Aloe leaf is cut the plant immediately release Acemannan degrading enzymes. Therefore, it is critical to start processing as quickly as possible after harvesting to minimize the loss of Acemannan through natural degradation. Many processing plants are located long distances from the Aloe fields and significant amounts of Acemannan are lost during transportation from the farming fields to the processing plants.
Recent scientific analyses of Aloe products revealed a wide disparity of Acemannan content.5, 6 Very few products had acceptable concentrations of Acemannan (≥10 w/w) while many had very poor concentrations of Acemannan (1 w/w or less). In others, there was high 'mannose' content but the Acemannan was so degraded that there was little or no activity and finally others contained undesirable biologically active contaminants. These problems are so wide spread that the International Aloe Science Council (IASC) is setting Acemannan content standards to ensure that quality products are delivered to consumers. Ideally, Aloe preparation should start immediately after harvest to inactive Acemannan degrading enzymes, avoid the use of high heat, dramatic changes in pH and alcohol extraction, and take place in Good Manufacturing Practices compliant facilities.
Myth: Fresh Aloe is better than processed Aloe
False. With proper methodology, processed Aloe can deliver much higher concentrations of active ingredients in an optimal size and solubility for presentation to the body. Processed Aloe can be formulated with other ingredients, which complement and enhance the activity of natural Aloe. Further, processed Aloe is stable, can be shipped anywhere, and stored for extended periods until ready for use whereas fresh Aloe must be used immediately.
Misconception: Aloe is better with the rind
Not necessarily true. The Aloe vera leaf can be divided into two main components, the outer rind and the inner leaf gel. Most of the well-known medicinal properties associated with Aloe, such as wound healing, digestive track balancing, and immunomodulation, are derived from the inner leaf gel. The rind also has some useful medicinal properties. For example, Aloe rind contains aloin, which among several activities is a potent laxative. Therefore, which is better or whether it is appropriate to have both depends upon the medical need. Generally, most products have focused on inner leaf gel.
Myth: All Aloe is bioavailable
False. Bioavailability is critically dependent upon solubility, which is in turn dependent upon the size of the Acemannan molecule. Acemannan is a long polysaccharide that is poorly soluble. The optimal molecular size for solubility and bioavailability is in the range of 50 kDa and can range up to 400 kDa. Studies have shown that post-harvest processing can dramatically affect the molecular size and shape of Acemannan, which can adversely affect solubility.3, 4 Thus, different processing methods can lead to wide variability in solubility and bioavailability. High molecular weight Acemannan actually has reduced bioavailability compared to lower molecular weight Acemannan. The ideal Aloe product would have a distribution of molecular weights the majority of which would be between 5 kDa and 400 kDa.
Misconception: Immunomodulation is immune stimulation
Wrong. The immune system is a complex group of specialized cells and cytokines that are designed to identify and eliminate foreign invaders in the body such as bacteria, viruses, and even our own cells that are sick (such as cancer cells or virally infected cells). Under healthy conditions, the immune system is at idle and quietly surveying for invaders and diseased cells. When invaders or diseased cells are detected the immune system springs to life, eliminates the threat, and returns to idle. Some immune-based diseases result from over or prolonged stimulation of the immune system while others result from under-stimulation or failure to respond. Immunostimulators can only stimulate the immune response while immunomodulators have the ability to balance the immune response in both a positive and negative direction in order to achieve a proper and healthy balance. Irritable bowel disease, arthritis, psoriasis, and allergies are all examples of diseases where over stimulation is an important component of the disease. Effective treatments for these diseases should be immunomodulatory to properly balance the immune system and not immunostimulatory or immunosuppressive. Acemannan is a true immunomodulator, which can promote a healthy and balanced immune system.7, 8
Myth: All Acemannan is equally active
Wrong. The activity of Acemannan is critically dependent upon its size and shape.8 Acemannan in fresh Aloe is thought to have a molecular weight of approximately 2,000 kDa. Studies have shown that the optimal size range for immunomodulation is between 5 kDa and 400 kDa4 and the optimal size for bioavailability is about 50 kDa. Thus, Acemannan molecules that are much larger than 400 kDa have reduced bioavailability and reduced immunomodulatory activity. Acemannan molecules that are smaller than about 5 kDa do not have the proper size and structure to be recognized by immune cells and thus have reduced or no immunomodulatory activity. An ideal Aloe preparation would have the majority of its Acemannan between 5 kDa and 400 kDa.
Misconception: Mannose is the primary active ingredient in Aloe
False. Acemannan, a long chain, mannose rich, polysaccharide is the primary active ingredient in Aloe vera inner leaf gel.1, 2 While there are many other secondary beneficial ingredients in Aloe vera, Acemannan is currently recognized as the primary active ingredient for most of the beneficial activities associated with Aloe vera. The structure of Acemannan is well known.9, 10 Mannose, a monosaccharide, is a major, but only one, component of the Acemannan. Acemannan is actually a polysaccharide composed of the three individual monosaccharaides, mannose, galactose, and glucose in a 3:1:1 ratio. The individual mannose and glucose monosaccharide\'s are linked together by β-1,4 glycosidic bonds to create long polysaccharide chains. Mannose and galactose are linked via β-1,6 glycosidic bonds. Most of the mannose and galactose molecules have additional chemical modifications, which help stabilize structure and increase solubility.
The activity of Acemannan is critically dependent upon its molecular size and shape.8 Thus, while mannose, galactose and glucose are important dietary monosaccharides and Aloe vera is a rich source of these monosaccharides, individually they are not capable of the many beneficial activities associated with Acemannan. The beneficial medicinal activities are critically dependent upon the structure of Acemannan.
AceAloe is a new Aloe vera product that contains the highest and most consistent Acemannan content of any Aloe product on the market today. For the manufacture of AceAloe , aloe plants are grown and harvested under certified organic conditions. The aloe leaves are processed using a proprietary method that preserves the integrity and activity of the primary active ingredient. AceAloe has been formulated with a proprietary blend of all natural herbs that both complement and enhance the natural activities of Aloe vera making it the most potent Aloe vera product on the market. AceAloe comes in capsule form with a recommended dose of 2 capsules a day.
Click here for a free copy of the AceAloe brochure
Literature Cited
1. Johnson A, White A, McAnalley B. Comparison of common topical agents for wound treatment: Cytotoxicity for human fibroblast in culture. Wounds: a compendium of clinical research and practice. 1989;1(3):186-192.
2. t\'Hart LA, Van den Berg AJ, Kuis L, Van Dijk H, Labadie RP. An anti-complementary polysaccharide with immunological adjuvant activity from the leaf parenchyma gel of Aloe vera. Planta medica. 1989;55(6):509.
3. Femenia A, Garcia-Pascual P. Effects of heat treatment and dehydration on bioactive pollsaccharide acemannan and cell wall polymers from Aloe babadensis Miller. Carbohdrate Polymers. 2003;51:397-405.
4. Ramachandra CT, Rao PS. Processing of Aloe veral leaf gel: A review. Am J Agricultural and Biological Sciences. 2008;3(2):502-510.
5. Bozzi A, Perrin C, Austin S, Vera F. Quality and authenticity of commercial aloe vera gel powders. Food Chemistry. 2007;103(1):22-30.
6. Turner CE, Williamson DA, Stroud PA, Talley DJ. Evaluation and comparison of commercially available Aloe vera L. products using size exclusion chromatography with refractive index and multi-angle laser light scattering detection. Int Immunopharmacol. Dec 20 2004;4(14):1727-1737.
7. Im SA, Lee YR, Lee YH, et al. In vivo evidence of the immunomodulatory activity of orally administered Aloe vera gel. Arch Pharm Res. Mar 2010;33(3):451-456.
8. Im SA, Oh ST, Song S, et al. Identification of optimal molecular size of modified Aloe polysaccharides with maximum immunomodulatory activity. Int Immunopharmacol. Feb 2005;5(2):271-279.
9. Manna S, McAnalley BH. Determination of the Position of the O-Acetyl Group in a -(1 4)-Mannan (Acemannan) from Aloe barbardensis Miller. Carbohydrate research. 1993;241:317-319.
10. Tai-Nin Chow J, Williamson DA, Yates KM, Goux WJ. Chemical characterization of the immunomodulating polysaccharide of Aloe vera L. Carbohydr Res. May 2 2005;340(6):1131-1142.
Article Source: http://www.articlesbase.com
About the Author
Dr.Cowsert received his Bachelors of Science degree from the University of Florida,
(Gainesville). Dr. Cowsert received his PhD from Georgetown University Medical School (Washington, DC) where he focused on the molecular biology, immunobiology, and pathology of Human Papillomaviruses. He completed his postdoctoral studies at The National Cancer Institute (Bethesda, MD). Dr. Cowsert has over 20 years\' experience in the biotechnology industry where he has held positions of increasing responsibility from Senior Research scientist to executive C-level management positions. During his tenure in the biotechnology
industry Dr. Cowsert lead multiple drug discovery teams and worked on multiple drug development teams with direct interactions with the FDA. Much of Dr. Cowsert\'s scientific work has been supported by over $5M in highly competitive government grants from the National Institutes of Health and the National Cancer Institute. Dr. Cowsert has written many peer reviewed scientific articles and book chapters and has been an Editor for a peer reviewed scientific journal for 10 years. He has been an invited speaker at over 25 international scientific meetings and is an inventor on 140 issued US Patents. Dr. Cowsert has been an expert guest on many talk radio shows.
