In a pickle about industrial wastes dumped in the water supply? Nature provides an unexpected way to help clean up

Wednesday, September 29, 2010 by: S. L. Baker, features writer
Tags: industrial waste, pickle, health news

(NaturalNews) Here's a true-life tale of a scientific discovery that came about by serendipity -- all because some food distributors were in a pickle about, appropriately enough, pickles. U.S. Department of Agriculture (USDA) microbiologist Ilenys Perez-Diaz, who works for the USDA Agricultural Research Service (ARS), and colleagues were called upon to investigate a mystery. Why were some commercial dill pickles turning red? What the research team found, unexpectedly, while figuring out the pickle problem was evidence that a natural bacteria could have an unexpected beneficial impact on cleaning up waste water.

Some background: for thousands of years, humans throughout the world used natural fermentation (lactic acid fermentation) to preserve their vegetables -- and that's how natural pickles were developed from cucumbers. However, with the advent of industrial food production, more and more pickle manufacturers began adding dyes and other chemicals to pickles.

During Perez-Diaz's search for the culprit that was causing some commercial dill pickles to turn red, Lactobacilli were isolated from the spoiled jars of hamburger dill pickles that had turned crimson. Lactobacilli are a major part of the lactic acid bacteria group. Common and usually benign, they are part of the "good" bacteria present in the human body where they make up part of the healthy gut flora and inhibit the growth of some harmful bacteria and fungi.

The researchers added some of the species of Lactobacilli they had isolated from the spoiled red pickles to non-spoiled jars of hamburger dill pickles. What they found was that natural pickles (with no added coloring or only the spice turmeric added for color) did not turn red. But pickles in brines containing the common food coloring tartrazine did develop a red hue.

So what did this mean exactly? It turns out, the isolated species of Lactobacillus bacteria was specifically reacting with tartrazine, an azo dye. And the bacteria was doing something amazingly helpful that wasn't immediately apparent, too.

Azo dyes, like the one in the pickles that turned red, come from industrial waste (tartrazine is made from coal-tar derivatives) and account for approximately 60 to 70% of all dyes used in food and textile manufacturing. Some are known to be mutagenic. According to the National Cancer Institute (NCI), anything that causes a mutation (a change in the DNA of a cell) may harm cells and cause certain diseases, such as cancer.

In investigating the red pickle problem, the ARS researchers discovered for the first time that food-related Lactobacillus microorganisms can transform azo dyes into non-mutagenic substances. The findings from this work have been reported in the Journal of Applied Microbiology.

In a statement to the media, Perez-Diaz noted that considerable effort has been made to identify microorganisms capable of degrading azo dyes in wastewater. And if food-grade Lactobacilli turn out to be capable of degrading a range of azo dyes, they might become organisms of choice for treating waste water which is frequently contaminated with the dyes from textile and other industries.

For more information:
http://onlinelibrary.wiley.com/doi/10.1111/j...