MÄnuka honey
Manuka honey is a honey bees from the nectar of Südseemyrte ( Manuka ) honey produced, which is traditionally used as a natural remedy and has an antibacterial activity. The Südseemyrte (Latin: Leptospermum scoparium ), a relative of the Australian tea tree, has its home in the remote, mountainous regions of New Zealand and southeastern Australia.
History
The natives of New Zealand, the Maori use, traditional leaves and bark or extracts from it, and Manuka honey of the tree externally for disinfecting and support the healing of wounds and inflammation, and also internally for colds, bladder infections and other infections. New Zealand farmers are said to have been fed in the 1930s manuka honey to their cows to make them more resistant to diseases.
Ingredients
Honey contains hydrogen peroxide, caused by the fact that bees the enzyme glucose oxidase Add in the honey production. This causes sugar from the small amounts of hydrogen peroxide occur in honey and the honey thus is mildly antiseptic.
Manuka honey contains as an essential ingredient in addition to the sugars of honey in varying amounts of the non- peroxide antibacterial sugar degradation product methylglyoxal ( MGO ). Methylglyoxal is formed in the honeycomb by dehydration of the substance contained in the nectar of flowers in the Manukastrauchs dihydroxyacetone ( see below). The nectar itself is not a methylglyoxal present. Apparently, this substance developed after consumption of nectar by the bees and the transport to the hive.
In works of the Institute of Food Chemistry at the Technical University of Dresden, the concentration of the metabolite methylglyoxal was measured in some Manuka honey from New Zealand and its antibacterial effect is quantitatively demonstrated in vitro. Especially bactericidal properties observed against the pathogen, Staphylococcus aureus and Escherichia coli. For methylglyoxal, the minimum inhibitory concentration against both germs than 1.1 millimoles per liter (equivalent to 0.075 grams of methylglyoxal per kilogram) was determined. The determined using an HPLC method methylglyoxal content was up to 100 times higher than in conventional honeys in manuka honey.
Methylglyoxal has a high stability, due to its properties and molecular weight, in contrast to hydrogen peroxide. One can heat the honey even without reducing the Methylglyoxalgehalt.
Researchers at the University of Waikato (New Zealand) found that methylglyoxal is mainly caused by a catalytic effect. To solve various anions apparently in the "young" manuka honey dehydration of the ingredient dihydroxyacetone ( DHA) to methylglyoxal. This process takes place in the hive after the introduction of the honey. The MGO concentration in the "mature" honey correlated with the DHA concentration in the nectar, which in turn varies from bush to bush. The University has developed a measuring method with which the achievable by storage MGO concentration can be predicted in the honey. This could lead to medium term targeted breeding and cultivation of Manukasträuchern, enable the production of a highly effective honey.
The honey from the nectar of directly related Leptospermum - type Kanuka can not develop MGO; there is a lack of DHA as a starting material for the synthesis of MGO. However, since the pollen of Manuka and Kanuka are virtually indistinguishable, even Kanuka honey is often reported as Manuka honey. In the wild, New Zealand Kanuka and Manuka often grow in the immediate neighborhood, but bloom in succession. The beekeeper can partially the hives in the vicinity of this mixed vegetation stand, so that there are different honeys MGO content also by the natural blend of costumes.
The phenolic acids contained also in Manuka honey (about caffeic acid, ferulic acid, syringic acid ) and flavonoids ( quercetin, isorhamnetin, luteolin ) occur in low concentrations, without an antibacterial action to unfold.
Non - peroxide antibacterial potency
Commercial Manuka honeys are in terms of their non- peroxide antibacterial activity with a so-called Unique Manuka Factor = UMF (translated " unique manuka factor " ) in which the New Zealand Association of Active Manuka Honey Association, Inc. ( AMHA ) awards to licensees for corresponding honey qualities. To determine this factor, the antibacterial activity of manuka honey is compared with that of a phenol solution: for example, has a Manuka Honey UMF ® 20 the same non - peroxide antibacterial activity in vitro as a 20% phenolic solution. In contrast to the measurement MGO It is a measure of efficacy without the basis of a particular ingredient. For reference measurement requires at least two Petri dishes with the same bacterial cultures and measures after treatment with honey or phenol, the size of the resulting court. The method is still used today in New Zealand by some companies, but has the disadvantage that the results can vary greatly due to the physical conditions ( variations in bacterial cultures, inaccuracies in the circle forming the respective court ) so that only several measurements an approximately reliable mean result.
2006 was identified as an antibacterial active component in manuka honey at the Technical University of Dresden, methylglyoxal ( MGO ). The values measured with a specially developed HPLC method concentrations were depending on the variety of manuka honey about 20 to 800 milligrams per kilogram. Also, a correlation between the calculated using the method UMF values and the measured Methylglyoxalgehalten could be produced. The company Manuka Health New Zealand Ltd.. characterizes the Methylglyoxalgehalt the products sold by it manuka honeys with the brand MGO ®, followed by a number that specifies the minimum content of methylglyoxal in milligrams per kilogram of honey. Other vendors now follow this methodology by specifying also a MGO value ( Methylglyoxalgehalt ) to characterize the non- peroxide antibacterial potency. Further, the Methylglyoxalgehalt is as a base for the construction of the UMF value used instead of the experimental investigation by Hemmhoftests.
The importance of Methylglyoxalgehaltes in Manuka honey was both in terms of antibacterial efficacy as also discussed the toxicological safety of controversy .. Also the German expert Prof. Henle of the TU Dresden was critical in terms of natural history, high MGO values as well as with respect to their compatibility for the human organism.
Areas of application
Meanwhile Manuka honey is being investigated in clinical trials and partially applied. In the Department of Diabetology is used in a Berlin clinic manuka honey complementary to traditional methods of wound healing in the treatment of diabetic foot ulcers and other poorly healing wounds.
Through the use of honey as a wound dressing a moist wound environment is created. This is able to constantly disinfect themselves to complete the wound outward and provide them with essential nutrients. These properties are particularly important in burns, in which secondary infections represent a common and dreaded complication. Secondary infections can occur quickly due to the large attack surface for germs. The honey causes wounds heal faster and make fewer scars.
Evidence base
Larger published studies show no clinical evidence for honey products for the healing of chronic wounds. Heuer et al. therefore advocate the use of Manuka honey on non - chronic wounds, such as occur for example as a result of an injury, surgery or after radiation therapy. There have been few animal experiments or clinical studies on this variant of moist wound treatment.
The German Society for Wound Healing and Wound Care Association advises in its S3 guideline for local therapy of chronic wounds also on the use. The main problem in the treatment of Manuka honey was the development of pain, which can be attributed to the methylglyoxal.
Legal classification
In August 2005, a reported for the treatment of wounds finished preparation under the name Medihoney was approved by the European medical device. Medihoney is derived from the nectar of flowers of various Leptospermum species. The manufacturer had claimed in the preceded certification process, the effects are due to the osmotic effect, that would come about by purely physical means. This is provided in the commercial preparation according to the present knowledge about the antibacterial properties of the ingredient methylglyoxal units and the corresponding high concentrations analytically detected in question.
For medicinal use of Manuka honey there are no approved finished product, so that a reference is only allowed as recipe formulation or extended at the pharmacy.
Manuka honey is also offered health-related food as well as cosmetically used in skin care preparations.
Consumer deception with counterfeiting
The British Food Standards Agency warns consumers against frauds increasing with wrong manuka honey. Analysis results would show " that is apparently sold especially in England, but that of course also in the rest of Europe, much manuka honey, which is not a manuka honey. Specifically, it was found that no methylglyoxal, so therefore no actual value adding ingredient was included in these honeys. "New Zealand is an annual production of 1700 tonnes, however yearly 10,000 tons alleged manuka honey are sold worldwide. Only every fifth-sixth sold Manuka honey is therefore authentic. In the rest of it were in fact to other, inferior honeys. Dresdner food technologists were also among those in Germany childrens' a whole range of honeys identify where no methylglyoxal is included. These honeys were as manuka honey sold with corresponding " fantasy award amounts " such as active or active plus 10.