Similarly, it has recently been found that it has insect repellent effect on menthyl-3,8-diol. Quwenling is a very famous insect repellent product based on eucalyptus, which contains p-menthyl-3,8-diol (PMD), isopiperonyl alcohol and vanillol alcohol. In China, Quwenling has largely replaced the use of diethyl phthalate in insect repellent. Recently, a company called Chemian Technology ltd produced a natural PMD insect repellent called Citrepel.
Questice (Watkins, U.S. patent. 6,456,5438+0,844,2002-9-17) is also registered as a new product of insect repellent. Kalbe and Nentwig described the insect repellents of menthone glycerol ketal and menthyl lactate in their patents (German patent number 1984032 1).
Cooler than menthol.
20011Hoffman and his collaborators in Germany announced that they had found many times stronger compounds in natural malt than mint. They say that the most active 4- methyl -3-( 1- pyrrolidinyl) -2[5H]- furanone belongs to the cyclic methyl enaminone family, and its mint taste is 35 times stronger than menthol in the mouth and 5 12 times stronger than menthol in the skin. It lasts twice as long as menthol. The most active compounds are as follows:
Tasteless, slightly minty, tasteless
Threshold 1.5-3.0 ppm threshold 2.0-4.0 ppm threshold 0.02-0.06 ppm.
5- methyl -4-( 1- pyrrolidinyl) -3-[2H]- furanone 4,5-dimethyl -3-( 1- pyrrolidinyl) -2[5H]- furanone 4- methyl -3-( 1- pyrrole)
This research has received great attention. Someone commented, "We found the strongest mint-free refreshing agent in the world."
However, at the meeting of the Association of Edible Flavors and Chemicals on February 4, 2003, it was said that the effect of 4- methyl -3-( 1- pyrrolidinyl) -2[5H]- furanone in practical use was far from what expected, and since then, everyone's interest in it has weakened.
However, it is often biased to measure the effect in practical use from the theoretical threshold. At the same meeting, Mark ullman of the Millennium gave a large number of strength data of synthetic coolants.
Physiological cold taste from menthol and other substances
Menthol and related compounds with cool taste can act on the temperature sensor of human body and make people feel cool through the cold sensor. Similarly, these products can give people a burning or stinging feeling. If the concentration is high enough, menthol and piperine can make people feel hot. In this case, it can stimulate people's nerves to feel hot and cold. Recently (200 1), Gordon Reid and Maria-Luiza Flonta of Bucharest found that some internal ions in a few sensory neurons of mice can be activated by moderate cooling. These phenomena exist in the cold sensor, such as stimulating with menthol and switching to continuous low temperature, which are all regulated by calcium ions and are very important for producing cold feeling. Early models pointed out that menthol stimulated cold receptors and blocked the voltage channel of calcium ions, which led to the decrease of intracellular calcium ions and inhibited the potassium channels dependent on calcium ions. However, Reed said that menthol stimulates the entry of calcium ions and greatly increases the concentration of calcium ions in cold sensory neurons. Therefore, the cooling effect of menthol can be simply expressed as activating the calcium ion current in the cold sensor.
In the March 2002 issue of Nature, McKemy, Neuhauser &; Julius described and cloned a menthol sensor located in trigeminal nerve cells, which responded to cold-to-cold stimuli. This cold mint sensor CMR 1 is a member of TRP excitation nerve channel. Its function is a conductor in the human sensory system. This discovery, like their previous findings on thermal sensors VR 1 and VRL- 1, shows how TRP neural channels sense temperature in a Wei Fan and how the peripheral nervous system of mammals senses temperature stimuli.
In the same issue of the magazine, Charles Zucker explained that cold ion channels can help solve the problem of encrypting and decrypting temperature information in the nervous system.
Similarly, Andrea Peier described and cloned TRPM8, a cooling sensor that can respond to cold and some coolant.
In March 2000, Viana and his collaborators showed that the cold sensor is not a specific group of conducting tissues, but a part of mixed ion channels of sensory neurons.
Recently, in February 2004, Behrendt published his research results, describing the reaction of cold mint sensor TRPM8 to 70 mints and similar compounds. These tests use FLIPR (Optical Disk Reader) to read the content. Among them, ten substances have muscle contraction reaction (linalool, geraniol, hydroxyvanillin, WS-3, WS-23, Frescolatmga, Frescolatml, PMD 38, Coola CTP, coolant 10). The strength and ratio readings of various products are shown in the following figure. With a few exceptions, the meanings expressed in the figure are the same as those in the above figure. This study gives another method to measure cold-tasting compounds.