2016年8月21日星期日
Chemical pigment
A pigment is a chemical material, which alters the color of reflected or transmitted light due to wavelength-selective absorption.
This press release was orginally distributed by SBWireDyes and pigments find multiple applications in paints & coatings, printing inks, textile, construction, and plastics . The paint and coating industry is witnessing major growth due to growing infrastructure . Major driving factors of the pigments and dyes market are increasing demand for high performance pigments (HPP), increasing usage of environment-friendly products, and application in end-user industries.
Demand for pigment and dye products such as printing ink is driven by several factors such as technological development and increasing demand for digital inks. Increase in end-user preference for environment-friendly products is likely to drive growth of the dyes and pigments market in the near future. Some of the factors restraining growth of the pigments and dyes market are environmental concerns, raw material price volatility and it's global over capacity . Some of the recent trends in the pigments and dyes market are shifting of manufacturing facilities from the U.S. and Europe to India, China, and Taiwan, and the rising preferences for eco-friendly products. Since specialty pigments are eco-friendly in nature, they are expected to increase demand for pigments and dyes .
With its emerging economies and quickly growing manufacturing bases, Asia Pacific accounts for the largest market and is likely to remain as the highest growing region in the years to come . Also due to the emerging trend such as shifting of manufacturing facilities from U.S. and Europe to India, China and Taiwan and increasing preference towards eco-friendly products . Asia Pacific is further followed by North America and Europe.
Some of the key players in the pigments and dyes market include Cathay Pigments, Inc., Sun Chemical Corporation, Dainichiseika Color & Chemicals Mfg. Co., Ltd., E.I. du Pont de Nemours and Company, Ferro Corp, Flint Group, Heubach GmbH, Huntsman International, LLC., Ishihara Corporation, Kemira Oyj, Kronos Worldwide, Inc., Lanxess AG, Merck KGAA, Silberline Manufacturing Co., Inc., The Shepherd Color Company, Toyo Ink SC Holdings Co., Ltd. and Tronox, Inc.
2016年8月18日星期四
Enjoy the health.enjoy the life
he "weakest link" is currently a hot (or cool, depending on your generation) concept, owing to the TV quiz show of that name. As children, we all learned the lesson that it takes only one weak link to break a chain. That lesson has been put to good use by grownup scientists who have figured out where the weak links are in some of the chains of chemical reactions that constitute our bodies' metabolic processes.
The next trick is to find ways to use that knowledge to our advantage. One powerful and productive way is to supplement with an extract of red yeast rice, an ancient food from Southeast Asia, to inhibit cholesterol production. Growing evidence suggests that there's much more to red yeast rice than that, but for now, let's focus on cholesterol.
 |
| A Chinese rice paddy. There is evidence that rice has been cultivated in this manner for at least |
Most of our cholesterol comes from our liver, which normally churns out about 600 mg of the much-maligned stuff every day. That's actually a good thing, however, because cholesterol is a molecule that's as vital to life as, say, insulin. Without it, we would soon die - but unless you're on a pathologically low-fat diet (less than about 10% fat), you'll never need to worry about inadequate cholesterol levels. The real problem is that withcholesterol - with too much of it clogging our arteries, to be more accurate - we also die, although that takes longer. It can take several decades, and then, one fateful, too-soon day - Boom! - a heart attack or stroke. RIP.
So, like the fairytale Goldilocks, who always had three choices in the bears' home, what we really want is for our cholesterol levels to be not too low and not too high, but Just Right. And that's where red yeast rice comes in.
RED YEAST RICE CONTAINS STATINS
Red yeast rice originated over a thousand years ago in China. It is produced when a purple-colored yeast, Monascus purpureus, is added to steamed rice and the mixture is fermented. The resulting product has been used as a food (and a food-coloring agent) since at least the year 800 A.D. Its use in winemaking in East Asia goes back more than 600 years, and it has a long history of use as a folk medicine for improving digestion and blood circulation.1
Red yeast rice originated over a thousand years ago in China. It is produced when a purple-colored yeast, Monascus purpureus, is added to steamed rice and the mixture is fermented. The resulting product has been used as a food (and a food-coloring agent) since at least the year 800 A.D. Its use in winemaking in East Asia goes back more than 600 years, and it has a long history of use as a folk medicine for improving digestion and blood circulation.1
Among its many other constituents, red yeast rice contains molecules called statins, which have a particular affinity for one of our molecules, an enzyme called HMG-CoA reductase(whenever you see a chemical name that ends in "-ase," you know it's an enzyme). Despite its ungainly name, this molecule plays an important role at a certain stage in the long, complex chain of reactions by which fats are converted to cholesterol in our livers. In that chain, HMG-CoA reductase is . . . you guessed it: the weakest link.
STATINS LOWER CHOLESTEROL LEVELS
An enzyme is a protein that acts as a catalyst, i.e., it speeds up a particular chemical reaction without itself participating in that reaction. If the structure or chemical properties of an enzyme are altered significantly, the enzyme is said to be inhibited - it can no longer catalyze the reaction, and the chain is broken. That is what statins, the main active ingredients in red yeast rice, do to HMG-CoA reductase.2
An enzyme is a protein that acts as a catalyst, i.e., it speeds up a particular chemical reaction without itself participating in that reaction. If the structure or chemical properties of an enzyme are altered significantly, the enzyme is said to be inhibited - it can no longer catalyze the reaction, and the chain is broken. That is what statins, the main active ingredients in red yeast rice, do to HMG-CoA reductase.2
The most prevalent of the statins in red yeast rice is called lovastatin. If that name sounds familiar, it's because lovastatin, along with several others, such as simvastatin, pravastatin, and mevastatin, are best-selling drugs, by far the most widely prescribed medications in the world for lowering cholesterol levels. They are considered to be extremely effective in this regard and are taken by about 12 million Americans. That number could soon soar, because in May 2001, the National Institutes of Health issued new cholesterol guidelines that call for tripling the number of Americans taking cholesterol-lowering drugs. What a bonanza that would be for the drug companies that sell statins!
RESEARCHERS STUDY RED YEAST RICE
Here, however, we wish to discuss another kind of bonanza: the health bonanza that you might be able to reap by taking powerful, effective, inexpensive statins in their natural, not synthetic, form, and with virtually no side effects to worry about. That's what red yeast rice offers, according to several studies done in China during the last few years.3-5 Now these results are supported by a study recently performed in the United States and published in the American Journal of Clinical Nutrition.6
Here, however, we wish to discuss another kind of bonanza: the health bonanza that you might be able to reap by taking powerful, effective, inexpensive statins in their natural, not synthetic, form, and with virtually no side effects to worry about. That's what red yeast rice offers, according to several studies done in China during the last few years.3-5 Now these results are supported by a study recently performed in the United States and published in the American Journal of Clinical Nutrition.6
The researchers, at UCLA, designed a randomized, double-blind, placebo-controlled clinical trial to evaluate the cholesterol-lowering effect of a commercial red yeast rice supplement over a 12-week period. The participants were 83 otherwise healthy adults (46 men and 37 women aged 34-78) who were diagnosed with hypercholesterolemia, or high blood cholesterol. Divided into two groups, they received either placebo or 2400 mg per day of red yeast rice powder. They were all requested to adhere to a standardized diet approved by the American Heart Association.
The subjects' blood was tested periodically for LDL (low-density lipoprotein,the "bad" form of cholesterol), HDL (high-density lipoprotein, the "good" form of cholesterol), total cholesterol, and triglycerides (fats). In our blood, cholesterol and triglycerides are the two major types of fatty substances, which are known generically as lipids.
The results of the study confirmed what had long been known in China: red yeast rice sharply reduces cholesterol levels. In the treatment group, LDL levels dropped by an average of 22% after 12 weeks, whereas the control group saw only a 1% drop. This is very significant, because LDL is the type of cholesterol chiefly implicated in the formation of artery-clogging plaque, which can lead to atherosclerosis and, ultimately, a heart attack. The red yeast rice also caused a significant drop in triglycerides, but it had no effect on HDL levels. No significant adverse effects were noted.
OXIDATION CAN KILL YOU
Plaque formation is a complex process involving the subtle interplay of many factors. In this deadly drama, it is actually the oxidized forms of LDL and triglycerides, not the lipids in their native forms, that are the chief villains. Oxidation is brought about by the destructive action of free radicals in the blood. That is why it is so important not just to keep our cholesterol and triglyceride levels in check to begin with, but also to keep our antioxidant defenses fully mobilized at all times, so as to prevent the conversion of these lipids to the forms that can kill us.
Plaque formation is a complex process involving the subtle interplay of many factors. In this deadly drama, it is actually the oxidized forms of LDL and triglycerides, not the lipids in their native forms, that are the chief villains. Oxidation is brought about by the destructive action of free radicals in the blood. That is why it is so important not just to keep our cholesterol and triglyceride levels in check to begin with, but also to keep our antioxidant defenses fully mobilized at all times, so as to prevent the conversion of these lipids to the forms that can kill us.
LOWER CHOLESTEROL MEANS LOWER RISK OF HEART ATTACK
A statistical link has been established between total cholesterol levels in the blood and the risk of heart attack: For every 1% reduction in total cholesterol, there is a 2% reduction in the risk of fatal and nonfatal heart attack.7,8 In the UCLA study, total cholesterol levels dropped 16% after 12 weeks. By this formula, therefore, the risk of heart attack in those individuals should have dropped about 32% - not bad! Where else can you get a two-for-one deal like that?
A statistical link has been established between total cholesterol levels in the blood and the risk of heart attack: For every 1% reduction in total cholesterol, there is a 2% reduction in the risk of fatal and nonfatal heart attack.7,8 In the UCLA study, total cholesterol levels dropped 16% after 12 weeks. By this formula, therefore, the risk of heart attack in those individuals should have dropped about 32% - not bad! Where else can you get a two-for-one deal like that?
OTHER COMPOUNDS IN RED YEAST RICE MAY HELP TOO
An unexpected feature of the study results was that the magnitude of red yeast rice's cholesterol-lowering effect was greater than could be accounted for solely on the basis of its content of lovastatin and other statins. The authors speculated that other compounds naturally present in red yeast rice (there are many different kinds) may also have an effect on cholesterol biosynthesis. Other researchers have speculated that some components of red yeast rice may have antioxidant effects, which, as we have just seen, would make this food product that much more beneficial to our health.9
An unexpected feature of the study results was that the magnitude of red yeast rice's cholesterol-lowering effect was greater than could be accounted for solely on the basis of its content of lovastatin and other statins. The authors speculated that other compounds naturally present in red yeast rice (there are many different kinds) may also have an effect on cholesterol biosynthesis. Other researchers have speculated that some components of red yeast rice may have antioxidant effects, which, as we have just seen, would make this food product that much more beneficial to our health.9
The possible role of other, perhaps unknown, compounds in the action of red yeast rice illustrates an important point about natural products vs. the synthetic drugs that are derived from them. The synthetics are manufactured as pure compounds that are either chemically identical to a naturally occurring one (lovastatin, e.g., which is sold as Mevacor®)or closely related (simvastatin, e.g. - a methyl derivative of lovastatin, with similar properties, and sold as Zocor®). Although synthetics often have the advantage of higher potency than their natural counterparts, and they may be easier to ingest, they also suffer from some significant disadvantages - which is to say that the natural products have significant advantages.
HOW ARE NATURAL PRODUCTS BETTER THAN SYNTHETIC DRUGS?
In addition to the direct health benefits that natural products offer, they have certain advantages over synthetic drugs that make them ideally suited to a preventive health care program. Prevention, after all, is always preferable to therapy.
In addition to the direct health benefits that natural products offer, they have certain advantages over synthetic drugs that make them ideally suited to a preventive health care program. Prevention, after all, is always preferable to therapy.
Minimal Side Effects
One advantage of natural products, such as red yeast rice, is that they tend to have minimal side effects. By contrast, when the body is confronted with a synthetic drug, it may see the drug as a foreign agent and decide that it's hostile, despite the beneficial role the drug is playing. (It's as though the body is saying, "OK, thanks for the help, but I still hate the fact that you're an alien. Get out!")
One advantage of natural products, such as red yeast rice, is that they tend to have minimal side effects. By contrast, when the body is confronted with a synthetic drug, it may see the drug as a foreign agent and decide that it's hostile, despite the beneficial role the drug is playing. (It's as though the body is saying, "OK, thanks for the help, but I still hate the fact that you're an alien. Get out!")
It's common for synthetic drugs to have a number of side effects, often quite serious. That happens not to be the case with the statins, however, which enjoy a good reputation in this regard: they're not only safe and effective, but relatively free of side effects as well. Nonetheless, natural red yeast rice is still preferable to the statin drugs, on principle and for the following reasons too.
Biochemical Richness
Another advantage of natural products (plant products such as red yeast rice, or herbal extracts) is that nature has typically endowed them with a rich mix of chemical compounds - many of which we have not even identified, in most cases - that can work together like a symphony orchestra, adding up to more than the sum of their parts. This is what appears to have occurred in the UCLA study with red yeast rice. Often we cannot fathom these interlocking webs of interactions, because they're far too complex.
Another advantage of natural products (plant products such as red yeast rice, or herbal extracts) is that nature has typically endowed them with a rich mix of chemical compounds - many of which we have not even identified, in most cases - that can work together like a symphony orchestra, adding up to more than the sum of their parts. This is what appears to have occurred in the UCLA study with red yeast rice. Often we cannot fathom these interlocking webs of interactions, because they're far too complex.
The magnitude of red yeast rice's
cholesterol-lowering effect
was greater than could be
accounted for solely on the
basis of its statin content.
By contrast, when synthetic drugs are chemically isolated from the parent natural product, they're isolated as well from the many beneficial interactions that would have been possible between them and the compounds they left behind. Their action, therefore, despite its clear focus, may lack the rich texture of nature's way. (A solo violin is nice, but a violin with anorchestra . . . )
And that's with a daily serving of only 2400 mg (2.4 grams), the amount used in the UCLA study. By comparison, the typical daily consumption of red yeast rice in many Asian countries is 14-55 grams - roughly ten times as much. Not coincidentally, perhaps, cholesterol levels are low in that part of the world, and so is the rate of atherosclerosis, which in our part of the world is the leading cause of premature death.
RED YEAST RICE - THE HEALTHY ALTERNATIVE
The cost factor prompted one of the UCLA authors to remark, "As a society, we are faced with rapidly increasing health care costs, including significant amounts of money spent for prescription drugs. Dietary supplements such as Chinese red yeast rice provide an alternative to prescription drugs. Because they may cost less and do not require a prescription, they are more accessible and may be used more widely."12 To this we could add that they can appropriately be viewed as preventive agents, as mentioned earlier.
The cost factor prompted one of the UCLA authors to remark, "As a society, we are faced with rapidly increasing health care costs, including significant amounts of money spent for prescription drugs. Dietary supplements such as Chinese red yeast rice provide an alternative to prescription drugs. Because they may cost less and do not require a prescription, they are more accessible and may be used more widely."12 To this we could add that they can appropriately be viewed as preventive agents, as mentioned earlier.
As we have seen, red yeast rice puts the brakes on cholesterol biosynthesis, reducing our levels of it and giving our poor, put-upon arteries a much-needed break. By itself, this is a fine thing, for those who have a cholesterol problem. Even for those who don't, however, red yeast rice may have a bowl of tricks up its sleeve that is only now coming to be appreciated, owing to new discoveries regarding the statins. Recent research, e.g., has shown that statins help prevent heart attacks and strokes by a mechanism that is unrelated to their cholesterol-lowering action.
订阅：
博文 (Atom)