Tuesday, March 24, 2009

Why Do We Need Antioxidants?

Antioxidants have been found to be very important in preventing or decreasing the incidence of diseases such as cancer, heart disease, Alzheimer’s disease, macular degeneration and aging in general. Antioxidants are also known to be important for maintaining healthy skin and immunity. Antioxidants are found naturally in foods, especially fruits and vegetables, and include vitamin C, polyphenols such as flavonoids, vitamin E, alpha lipoic acid and carotenoids.

"Lipid peroxidation" by Tim Vickers, after Young IS, McEneny J (2001).

What exactly do antioxidants do though? Antioxidants prevent or slow oxidative damage to molecules in the body’s tissues. This includes damage to lipids that make up the cell membrane, proteins that form the structure of skin and carry out metabolic processes, and DNA that carries the genes of the cell.

As any beginning student of biology has learned, oxidation reduction reactions are necessary for producing energy in the body. This chemical reaction transfers electrons from an oxidant to a reductant. These oxidation reactions can produce free radicals (or reactive oxygen species) that start a chain reaction that damages cells.

These oxidants are formed naturally by the body but are also formed from various environmental factors such as pollution and cigarette smoke and UV light as well as through some foods such as high fat and fried foods.

The only way to stop these series of oxidation reactions is with an antioxidant. The body does make some of its own antioxidants that include glutathione and superoxide dismutase. But antioxidants are naturally taken into the body through food, at least through healthy food such as fruits, vegetables and herbs.

Antioxidant strength can be measured in a number of ways including the ORAC test, DPPH radical scavenging assay and the ABTS assay.

Besides orally, antioxidants are also important topically. Some vegetable oils are high in antioxidants such as vitamin E and phytosterols. Infusing an oil with herbs can also add antioxidants to it. For instance, calendula which is high in carotenoids can release some of these carotenoids into an oil when it is infused. Various herbal extracts, green tea and cocoa can also provide antioxidants to skin care products used topically. Antioxidants are also added to food to help prevent deterioration of that food that occurs with exposure to air and sunlight. Oxidation of oils is what causes them to become rancid.

Wednesday, March 18, 2009

Gallic Acid Chemistry

Gallic acid is a plant chemical found in most plants but especially abundant in tea, grapes and oak. It is in a group of chemicals called phenolics. Phenolics are chemicals based on the structure of phenol which is a molecule with a ring structure containing 6 carbons with a –OH (hydroxyl group) attached to one of the carbons. A molecule with more than one phenol ring is called a polyphenol. These phenols and polyphenols are known as powerful antioxidants and found in many plants.

phenol can be written either way

gallic acid

Interestingly, this 6 member ring structure also referred to as an aromatic nucleus is only synthesized by plants and microorganisms, not animals or humans. Generally speaking phenolics are acidic meaning their pH is low (from 1-7).

Gallic acid has 3 –OH groups and one –COOH (carboxylic acid) group attached to the ring. Note that in these abbreviated structures shown that each of the 6 corners represents a carbon atom, so there are 6 carbon atoms in phenol.

Gallic acid can be found either alone or as part of plant tannins. Tannins are a family of high molecular weight, water soluble plant molecules. Another definition of tannin is a natural product containing phenolic structures that can precipitate proteins. They have an astringent taste (think tea) and have the ability to tan leather. When gallic acid becomes linked to a sugar such as glucose it can form a polygalloyl ester which is a simple type of tannin.

Gallic acid itself is an antifungal agent, antiviral, astringent and antioxidant. Some studies have indicated that it has anticancer activity and that it can relax blood vessels. Gallic acid isjust one of many polyphenols found in tea and grape seed that provide health benefits. Gallic acid is soluble in water and has a boiling point of 251 degrees C. This is a low enough temperature that it can be found in the distilled products of herbs.


Monday, March 9, 2009

Wordless Wednesday Madgellan, Snow, Moon

This is a picture of Madgellan, our Leghorn rooster with his hens behind him. Picture taken on Monday.
Footprints in the snow on Tuesday morning.

Moon setting over the mountains on Wednesday morning. Snow is gone but its cold.

March is a Difficult Month

I have always loved spring. I feel joy and gaiety in the newness it brings as browns turn to green and the cycle repeats. In recent years that gaiety is steadied with feelings of wistful melancholy for with that rebirth comes the pain of loss. My older brother died just two weeks ago, my Mother died 3 years ago in March and my sister died 5 years ago in March. So, with each seed I plant I memorialize my loved ones who have gone before me and the cycle of life becomes much more than a garden theme but a prayer for my family. So I go to my greenhouse and plant tomato seeds in hopes that over the next few months I can watch them grow and then later this summer produce tomatoes for me.

I purchased my tomato seeds this year from Territorial Seed company. The include:

Gold Medal, Silvery Fir Tree, Koralik, Manitoba, and Brandywine. These are all heirloom tomatoes and I also have Stupice, an early tomato that is not heirloom. I also have cabbage (Gonzales hybrid), cucumber (marketmore, green slam) and eggplant (millionaire). One thing I always look for when choosing seeds is the time to harvest since we can get very cold even in early June and as early as late August.

I also have some seed from Botanical Interest that I will plant in a cold frame; my raised bed covered with plastic. These include; basil, spinach radicchio, lettuce (mesclun mix) and arugula. I love Botanical Interest both because they are a local company and because the artwork on their packages is so beautiful; I should save the packages for a collage of sorts. Last year my Herb Society group took a tour through their facility and we had a great time. The owner, Curtis Jones, is very nice, helpful and knowledgeable. I should also plant calendula in the greenhouse since that is an herb I use frequently in my products and can never get enough of.

If you haven’t ordered seeds yet, here are some seed company names I have collected.


Gary Jones, 1953-2009


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