Tag Archives: Antimicrobial

Canadian study finds soy can be used as an antibacterial agent

Posted on by
Reply

A new study from the University of Guelph has found soy can limit the growth of some bacteria, such as listeria and pseudomonas, and it does it better than chemical-based agents.

Soybeans-legumes“Current synthetic-based, chemical-based anti-microbial agents kill bacteria indiscriminately, whether they are pathogenic or beneficial,” researcher Suresh Neethirajan said.

The body – and in particular, the intestines – need good bacteria to properly process the food we eat.

The compounds in soybeans, however, do not kill off all bacteria, just the bad ones, Neethirajan said.

Soybean derivatives are already used in a variety of products including canned foods, cooking oils, meat alternatives, cheeses, ice cream and baked goods.

Neethirajan, an engineering professor and director of the BioNano Laboratory at the university, said those with soy allergies need not worry about soy being used to prevent bacteria growth.

He said their method isolates the active component of the soybean from the protein that causes allergic reactions. The soy isoflavones that are chemically similar to estrogen are also weeded out.

What is left is a compound that naturally stops the bad bacteria.

Neethirajan’s study will appear in the July edition of the journal Biochemistry and Biophysics Reports.

Not so: Antibacterial handwash ‘no better than soap at killing germs’

Posted on by
1

Food micro geek Don Schaffner of Rutgers University responds in a point-counterpoint style discussion of antibacterials in soap and effectiveness.

point.counterpointAccording to the story, a new study published in the Journal of Antimicrobial Chemotherapy found that antibacterial handwash is no more effective than plain soap at killing bacteria.

In recent years numerous products have appeared on the shelves claiming they were effective in killing 99.9 per cent of all germs.

But Korea University scientists investigated the effect of triclosan, the most commonly used active antiseptic ingredient in soap, in everyday conditions on bacteria such as MRSA, salmonella and listeria.

In recent years numerous products have appeared on the shelves claiming they were effective in killing 99.9 per cent of all germs. That’s actually a regulated label claim.  And it’s not “99.9 per cent of all germs.”  It’s 99.9 percent (3 log reduction for the math nerds) of certain regulatory-specified organisms under specified test conditions.

One central key weakness of the study is that authors state in their methods, “Antibacterial soap had the same formulation as plain soap except that it contained 0.3% triclosan.” While this might seem to be a good idea from the science perspective, it turns out that soap formulation is a tricky business. For antimicrobials to be optimally effective, the formulation might need to be adjusted. You can’t just throw sh*t in at ‘the maximum allowed by law’ and expect it to work.

Improving the safety of leafy greens: USDA

Posted on by
Reply

Food safety is a top priority for consumers, especially when it comes to the leafy greens in salads. Researchers at the University of Arizona have discovered natural methods to sanitize these vegetables using ingredients commonly found in the kitchen, such as oregano, cinnamon, and vinegar.

lettucePlant extracts, essential oils, and organic sanitizers have all proved effective in killing bacteria on leafy greens and extending their shelf life. When emulsified in the water used to wash these leaves, the approach compares to (and sometimes even works better than) bleach or hydrogen peroxide.

“Plant antimicrobials can be used by consumers at home,” said Sadhana Ravishankar, associate professor at the University of Arizona’s School of Animal and Comparative Biomedical Sciences. “Plant extracts and essential oils can be added in the wash water by themselves or combined with vinegar in the wash water for treatment.”

Benefits of using plant antimicrobials and organic sanitizers are that they are natural, environmentally friendly, and less energy intensive since they are effective at both room and cold temperatures. They also continue to kill bacteria during storage; their effectiveness is not reduced in the presence of organic matter; and they have added health benefits linked to a reduction in the occurrence of cancer, diabetes, and high cholesterol. The wash water containing plant compounds and organic sanitizers can also be recycled and reused without a loss in effectiveness.

“We have also researched a new way of applying plant antimicrobials to improve salad safety,” said Ravishankar. “We have incorporated plant essential oils into edible films that are added into salad bags and the vapors from the oils kill the bacteria in the salad bags during storage. Edible films are also plant-based sources such as apples, carrots, hibiscus, or spinach pulp.”

The project team has been using social media as an educational tool for the benefit of growers and other stakeholders.  The social media campaign includes YouTube videos, Facebook, and Twitter.

The outcomes of this project will benefit consumers by reducing and preventing contamination of the leafy greens by foodborne pathogens at the production and harvesting levels, providing a safer product in stores and on their tables.

Moving forward, Ravishankar and her team are testing combinations of plant antimicrobials and the effectiveness of them when the wash water is recycled.  USDA’s National Institute of Food and Agriculture (NIFA) is funding this new research, a four-year, $2,907,354 Organic Agriculture Research and Extension Initiative (OREI) grant.

OREI seeks to solve critical organic agriculture issues, priorities, or problems by integrating research, education, and extension activities. OREI-fund projects that will enhance the ability of producers and processors who have already adopted organic standards to grow and market their high quality organic agricultural products.

Antimicrobial potential of cauliflower, broccoli, and okara byproducts against foodborne bacteria

Posted on by
Reply

The antimicrobial potential of cauliflower, broccoli, and okara byproducts was assessed against Gram-positive and Gram-negative bacteria. Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7, Bacillus cereus, and Listeria monocytogenes serovar 4b.

cauliflowerGrowth behavior was assessed under exposure to 5% vegetable byproducts added to the reference medium, buffered peptone water (0.1% [wt/vol]), at 37°C. Although the byproducts were not effective against L. monocytogenes, they were bactericidal against Salmonella Typhimurium, E. coli O157:H7, and B. cereus. The most promising results were achieved with the cauliflower–Salmonella Typhimurium combination, because the bacterial population was reduced by 3.11 log10 cycles after 10 h of incubation at 37°C as a result of 5% cauliflower addition. Further studies were carried out for this combination, at different cauliflower concentrations (0, 0.5, 1, 5, 10, and 15%) and at temperatures in the range of 5–37°C. The greatest inactivation level (6.11 log10 cycles) was achieved at refrigeration temperature (5°C) using 15% cauliflower addition. Both temperature and cauliflower concentration significantly (p≤0.05) influenced the Salmonella Typhimurium inactivation level. The kinetic parameters were adjusted to mathematical models.

broccoliThe modified Gompertz mathematical model provided an accurate fit (root-mean-square error (RMSE) [0.00009–0.21] and adjusted-R2 [0.81–0.99]) to experimental Salmonella Typhimurium survival curves describing inactivation kinetics of the pathogen to the antimicrobial effect of cauliflower byproduct.

 

Antimicrobial potential of cauliflower, broccoli, and okara byproducts against foodborne bacteria

Foodborne Pathogens and Disease. January 2015, 12(1): 39-46

Sanz-Puig Maria, Pina-Pérez Maria C., Criado Maria Nieves, Rodrigo Dolores, and Martínez-López Antonio

http://online.liebertpub.com/doi/abs/10.1089/fpd.2014.1801#utm_source=ETOC&utm_medium=email&utm_campaign=fpd

Quantifying antimicrobial-resistant E. coli and Salmonella enterica in beef production

Posted on by
Reply

Specific concerns have been raised that third-generation cephalosporin-resistant (3GCr) Escherichia coli, trimethoprim-sulfamethoxazole-resistant (COTr) E. coli, 3GCr Salmonella enterica, and nalidixic acid-resistant (NALr) S. enterica may be present in cattle production environments, persist through beef processing, and contaminate final products.

grass-fed.beefThe prevalences and concentrations of these organisms were determined in feces and hides (at feedlot and processing plant), pre-evisceration carcasses, and final carcasses from three lots of fed cattle (n = 184). The prevalences and concentrations were further determined for strip loins from 103 of the carcasses. 3GCr 

Salmonella was detected on 7.6% of hides during processing and was not detected on the final carcasses or strip loins. NALr S. enterica was detected on only one hide. 3GCr E. coli and COTr E. coli were detected on 100.0% of hides during processing. Concentrations of 3GCr E. coli and COTr E. coli on hides were correlated with pre-evisceration carcass contamination. 3GCr E. coli and COTr E. coli were each detected on only 0.5% of final carcasses and were not detected on strip loins. Five hundred and 42 isolates were screened for extraintestinal pathogenic E. coli (ExPEC) virulence-associated markers. Only two COTr E. coli isolates from hides were ExPEC, indicating that fed cattle products are not a significant source of ExPEC causing human urinary tract infections. The very low prevalences of these organisms on final carcasses and their absence on strip loins demonstrate that current sanitary dressing procedures and processing interventions are effective against antimicrobial-resistant bacteria.

 

FDA rule could end consumer access to antibacterial soaps

Posted on by
Reply

Food safety nerd Don Schaffner says antimicrobials have a role, and I usually agree with Don (right, not exactly as shown).

 77fdonuts1In an effort to maintain consumer access to the benefits of antibacterial soaps, the American Cleaning Institute (ACI) and the Personal Care Products Council, along with input from leading independent scientists, filed extensive comments with FDA on its proposed rule. The comments demonstrate to the Agency that consumer antibacterial soaps are safe, effective, and promote public health.

The FDA’s proposal could eliminate the public’s access to safe and effective antibacterial soaps, including kitchens in the home and at daycare facilities.

Antibacterial soaps “are critical to public health because of the importance hand hygiene plays in the prevention of infection,” wrote the groups in their joint June 16 comments to FDA. “Washing the hands with an antiseptic handwash can help reduce the risk of infection beyond that provided by washing with non-antibacterial soap and water.”

FDA appears to have not considered that the consumer category includes use of antibacterial soaps in public areas such as schools, airports, daycares, and other facilities. Consumer antiseptic products reduce the level of bacteria on skin, which reduces the risk of infection and disease.

sopranos.don't.fuck.with.usElimination of these products would put the general population at risk. For example, individuals using public restrooms would no longer have access to antiseptic hand soaps. 

The Topical Antimicrobial Coalition, which comprises ACI and the Council, estimated the costs of the proposed rule – associated with preventable gastrointestinal illnesses – that would occur if antiseptic hand wash products were not available.

The number of new cases of foodborne illness caused by bacteria such as E. coli, Salmonella, Shigella, and Campylobacter could range between 250,000 and 7.5 million, based on projections by Dr. Donald Schaffner, Professor at Rutgers University’s Food Science Department.

The groups’ comments also take issue with assertions in the proposed rule that challenge the safety of antibacterial ingredients.

“No scientific studies currently exist to demonstrate a correlation between the active ingredients considered in the proposed rule and adverse health effects on consumers. As a result, there are no measureable benefits of the proposed rule.”

FDA not sure antimicrobial soaps do anything

Posted on by
5

Every day, consumers use antibacterial soaps and body washes at home, work, school and in other public settings. Especially because so many consumers use them, the U.S. Food and Drug Administration believes that there should be clearly demonstrated benefits to balance any potential risks.

There currently is no evidence that over-the-counter (OTC) antibacterial soap products are any more effective at preventing illness than antimicrobial.soapwashing with plain soap and water, says Colleen Rogers, Ph.D., a lead microbiologist at FDA.

Moreover, antibacterial soap products contain chemical ingredients, such as triclosan and triclocarban, which may carry unnecessary risks given that their benefits are unproven.

“New data suggest that the risks associated with long-term, daily use of antibacterial soaps may outweigh the benefits,” Rogers says. There are indications that certain ingredients in these soaps may contribute to bacterial resistance to antibiotics, and may have unanticipated hormonal effects that are of concern to FDA.

In light of these data, the agency issued a proposed rule on Dec. 13, 2013 that would require manufacturers to provide more substantial data to demonstrate the safety and effectiveness of antibacterial soaps. The proposed rule covers only those consumer antibacterial soaps and body washes that are used with water. It does not apply to hand sanitizers, hand wipes or antibacterial soaps that are used in health care settings such as hospitals.

Can oregano make healthier chickens?

Posted on by
1

There’s lots of stories about food safety miracle spices and cures, but often in the absence of valid verification.

So the New York Times decided to further erode its scientific credibility by running a story about Bell & Evans, a Pennsylvania poultry producer that feeds chickens a specially milled diet laced with oregano oil and a touch of cinnamon.

Scott Sechler swears by the concoction as a way to fight off bacterial diseases that plague meat and poultry producers without oregano.smoke.dec.12resorting to antibiotics, which some experts say can be detrimental to the humans who eat the meat.

Skeptics of herbal medicines abound, as any quick Internet search demonstrates. “Oil of oregano is a perennial one, advertised as a cure for just about everything,” said Scott Gavura, a pharmacist in Toronto who writes for the Web site Science-Based Medicine. “But there isn’t any evidence, there are too many unanswered questions and the only proponents for it are the ones producing it.”

The oregano oil product Mr. Sechler uses, By-O-Reg Plus, is made by a Dutch company, Ropapharm International. In the late 1990s, Bayer conducted trials on the product, known as Ropadiar in Europe, comparing its ability to control diarrhea in piglets caused by E. coli with that of four of the company’s products.

In all four test groups, Ropadiar outperformed the Bayer products. “Strange but true!” Dr. Lucio Nisoli, the Bayer product manager, wrote in his report on the trial. “Compared to the various anti-infectives, with Ropadiar I have obtained much more effective and quicker results. Furthermore, piglets treated with Ropadiar look much more healthy and were not so dehydrated and wasted.”

Astrid Köhler, a spokeswoman in Monheim, Germany, for Bayer Healthcare’s animal health business, confirmed that the company had done the trial but said that “in further evaluations the results of the first study could not be replicated with the same species, nor with other species.”

Other testing is rare. A test of oregano oil on four small farms in Maine, which was financed by a $9,914 grant from the Agriculture Department, found it was effective in controlling the parasites and worms that afflict goats and sheep.

After a chicken flock leaves a barn at Bell & Evans for slaughter, for instance, the facility is hosed down, its water lines are cleaned out and everything is disinfected. It sits empty for two to three weeks to allow bacteria to die off and to ensure that the rodents that carry salmonella and campylobacter are eliminated.

“You can’t just replace antibiotics with oregano oil and expect it to work,” Mr. Sechler said.

FDA with expanded powers buckles to industry demands on antibiotic testing?***

Posted on by
1

I got a phone call about this story about 10 days ago while visiting family in Minnesota. I checked it out, thought there was merit, but there were many agendas at play.

The N.Y. Times apparently got the same phone call, checked it out, and is running with a story tonight about government and industry and antibiotic residues in culled dairy cattle.

It’s not clear who’s an advocate for what in these kinds of stories. Excerpts below.

Each year, U.S. inspectors find illegal levels of antibiotics in hundreds of older dairy cows bound for the slaughterhouse. Concerned that those antibiotics might also be contaminating the milk Americans drink, the Food and Drug Administration intended to begin tests this month on the milk from farms that had repeatedly sold cows tainted by drug residue.

But the testing plan met with fierce protest from the dairy industry, which said that it could force farmers to needlessly dump millions of gallons of milk while they waited for test results. Industry officials and state regulators said the testing program was poorly conceived and could lead to costly recalls that could be avoided with a better plan for testing.

In response, the F.D.A. postponed the testing, and now the two sides are sparring over how much danger the antibiotics pose and the best way to ensure that the drugs do not end up in the milk supply.

“What has been served up, up to this point, by Food and Drug has been potentially very damaging to innocent dairy farmers,” said John J. Wilson, a senior vice president for Dairy Farmers of America, the nation’s largest dairy cooperative. He said that that the nation’s milk was safe and that there was little reason to think that the slaughterhouse findings would be replicated in tests of the milk supply.”

But food safety advocates said that the F.D.A.’s preliminary findings raised issues about the possible overuse of antibiotics in livestock, which many fear could undermine the effectiveness of drugs to combat human illnesses.”

The F.D.A. said that it would confer with the industry before deciding how to proceed. “The agency remains committed to gathering the information necessary to address its concern with respect to this important potential public health issue,” it said in a statement.

The concerns of federal regulators stem from tests done by the Department of Agriculture on dairy cows sent to be slaughtered at meat plants. For years, those tests have found a small but persistent number of animals with drug residues, mostly antibiotics, that violate legal limits.

The tests found 788 dairy cows with residue violations in 2008, the most recent year for which data was available. That was a tiny fraction of the 2.6 million dairy cows slaughtered that year, but regulators say the violations are warning signs because the problem persists from year to year and some of the drugs detected are not approved for use in dairy cows.

“F.D.A. is concerned that the same poor management practices which led to the meat residues may also result in drug residues in milk,” the agency said in a document explaining its plan to the industry. In the same document, the F.D.A. said it believed that the nation’s milk supply was safe.

Today, every truckload of milk is tested for four to six antibiotics that are commonly used on dairy farms. The list includes drugs like penicillin and ampicillin, which are also prescribed for people. Each year, only a small number of truckloads are found to be “hot milk,” containing trace amounts of antibiotics. In those cases, the milk is destroyed.

But dairy farmers use many more drugs that are not regularly tested for in milk. Regulators are concerned because some of those other drugs have been showing up in the slaughterhouse testing.

Federal officials have discussed expanded testing for years. But industry executives said that it was not until last month that the F.D.A. told them it was finally going to begin.

The agency said that it planned to test milk from about 900 dairy farms that had repeatedly been caught sending cows to slaughter with illegal levels of drugs in their systems.

It said it would test for about two dozen antibiotics beyond the six that are typically tested for. The testing would also look for a painkiller and anti-inflammatory drug popular on dairy farms, called flunixin, which often shows up in the slaughterhouse testing.

The problem, from the industry’s point of view, is the lengthy time it takes for test results.

Resistance is not futile; antimicrobial use in agriculture

Posted on by
Reply

In 1969, the Swann report recommended strict oversight and restrictions on the use of antibiotics used in human medicine as growth promoters in agriculture. That was in the U.K., and 31 years later, the debate about the use of antimicrobials in agriculture continues.

The USA Today today and the N.Y. Times on Friday both waded into the issue in advance of House hearing on the issue on Wednesday.

USA Today said in an editorial that,

"high-volume use of antibiotics in animals is a dangerous avenue for the evolution of drug-resistant bacteria that can eventually spread to humans. But, in a classic case of the public interest taking a back seat to private commercial interests, the farm lobby has for decades successfully fought restrictions on animal use of antibiotics. Now federal regulators and some members of Congress are making a worthy new push to rein in hazardous practices.

“The Food and Drug Administration is sufficiently concerned that it issued a detailed, 19-page "draft guidance" last month that calls on the agriculture industry to voluntarily end the "injudicious" use of drugs to help animals grow, which it said "poses a qualitatively higher risk to public health" than using the drugs selectively to cure or prevent disease.”

The FDA says 30 years of studies point unmistakably to a hazard from overuse of antibiotics in animals.

The Centers for Disease Control and Prevention says humans could pick up drug-resistant bugs through contact with animals or by eating contaminated food; it cites the example of Campylobacter bacteria, which lives in chicken intestines and can cause diarrhea in humans who eat undercooked chicken.

In 1995, the FDA approved the use of fluoroquinolone antibiotics in chickens. Soon, though, doctors began to find Campylobacter strains in sick people that were resistant to fluoroquinolone, and the FDA eventually banned the antibiotic for use in chickens.

Dr. Howard Hill, a veterinarian and a director of the National Pork Producers Council, writes in an opposing view,

“America’s livestock farmers use antibiotics to keep their animals healthy and, in turn, to produce safe food for consumers. And, contrary to the opponents of modern food-animal production, antibiotics are not being given excessively to pigs and cattle, and their use in livestock production is not the likely cause for an increase in antibiotic resistance in humans.

A 2006 report from the Institute of Food Technologists concluded: "Eliminating antibiotic drugs from food-animal production may have little positive effect on resistant bacteria that threaten human health. … Who knows? The risk of not using antibiotics could outweigh any risk of using them.

Elizabeth Parker, chief veterinarian at the National Cattlemen’s Beef Association, wrote in Friday’s Times in response to a June 30 editorial that,

“Ranchers have an obligation to protect cattle health and welfare. We also have an obligation to protect human health by providing a safe beef supply. That’s why, for generations, cattle producers have worked closely with veterinarians in the careful use of antibiotics to prevent, control and treat disease.”

Judicious use guidelines have been around a lot longer than last month. It’s a way of an industry group saying, hey, we know this is a powerful technology, so we’ll use it carefully in order to retain access to the technology.

But, judicious use can evolve into routine use. The challenge is maximize the benefits of a technology while minimizing the risk. Science can be messy.