Good Thinking

Bacterial compound from raw pork snack could preserve food naturally

Bacterial compound from raw po...
A serving of Nem Chua
A serving of Nem Chua
View 2 Images
Listeria bacteria (green) dying after exposure to Plantacyclin B21AG – the bumps visible on many of the cells are the cell contents beginning to leak out
1/2
Listeria bacteria (green) dying after exposure to Plantacyclin B21AG – the bumps visible on many of the cells are the cell contents beginning to leak out
A serving of Nem Chua
2/2
A serving of Nem Chua

Despite the fact that it's made of fermented raw pork, the Vietnamese meat snack Nem Chua does not cause food poisoning in people who eat it. In fact, new research suggests that a compound found in it could be used as a natural food preservative.

In the recently conducted study, scientists from Australia's RMIT University took a closer look at the harmless Lactiplantibacillus plantarum B21 bacteria that occurs naturally in Nem Chua. Among other things, the researchers found that the microbes produce a compound known as a bacteriocin, which kills rival types of bacteria.

Bacteriocins in general work by forming holes in the outer membranes of their targets, causing their contents to leak out. One such compound – called Nisin – is actually already marketed as an antibacterial food preservative. Its usefulness is limited, though, due to the fact that it's sensitive to extremes in temperature and pH.

By contrast, the L. plantarum 21-derived bacteriocin – named Plantacyclin B21AG – is much hardier. The scientists state that it could easily withstand the extremes present in commercial food-processing environments, as it tolerates both high and low pH levels, and can survive being heated to 90 ºC (194 ºF) for 20 minutes.

What's more, unlike some other bacteriocins, it targets a wide range of harmful food-borne bacteria such as Listeria monocytogenes.

Listeria bacteria (green) dying after exposure to Plantacyclin B21AG – the bumps visible on many of the cells are the cell contents beginning to leak out
Listeria bacteria (green) dying after exposure to Plantacyclin B21AG – the bumps visible on many of the cells are the cell contents beginning to leak out

"The Nem Chua compound is colourless, odourless, tasteless and very resilient," says co-lead scientist Prof. Oliver Jones. "Through this new research, we’ve identified the right growth conditions that would enable us to make it in large amounts, potentially at industrial scales. With further development, we hope this could be an effective, safe and all-natural solution for both food waste and food-borne disease."

A paper on the research – which was co-led by Prof. Andrew Smith, Dr. Bee May and Dr. Elvina Parlindungan – was recently published in the journal Process Biochemistry.

Source: RMIT

3 comments
3 comments
Ralf Biernacki
I am afraid this will go the way of many antibiotics---after it becomes widely used, bacteria will develop resistance to it, and that will be it for plantacyclin. I wish we had the sense and temperance to keep such compounds in reserve, rather than seeking to "market" them in the broadest possible scope. But the economic impulse is even harder to restrain than the sexual one.
Karmudjun
So this bacterium has been killing other bacteria for how many centuries? Well, listeria seems susceptible during this study - but we all know bacteria always develop resistance. Oh doom and gloom.

When will we learn from nature that we just can't outwit evolutionary pressures?
Don Duncan
I eat only all grass-fed (pastured) meat/dairy. Animals raised as they evolved in the wild, e.g., without grain, antibiotics, hormones, are healthier, produce different meat/dairy. Is this throwback to centuries old stewardship better? It doesn't require chemicals, medicines, stockyard stresses. It is cheaper.
Most of all it focuses on building soil fertility. Past "farmers" were really miners of the soil fertility who ignorantly overgrazed, paid no attention to building up soil. The new "controlled grazing" adds multiple animals into a mix, e.g., chickens following behind the cows. They scatter the "pies" enriching the soil.