Nanosilver particles and antibiotics were both discovered in the 60s of the nineteenth century, at that time silver nanoparticles had high production costs, much less bactericidal efficiency than antibiotics that is why antibiotics there was a period of glorious development that lasted for several decades. Save the lives of countless patients, can not deny such great contributions. In recent years, antibiotic resistance is getting more and more serious, with more attention and attention. The use of antibiotics is strictly controlled. Antibiotic substitutes are searched and can be listed a number of such as: organic acids, probiotics, nanosilver … Recently, many products have been tested and applied to reduce the abuse of resistance. birth and show signs that deserve more attention.
NanoCMM Technology would like to share a little bit about antibiotics and nano silver so that everyone can have a clearer view of these 2 types of products.
What is an antibiotic?
Antibiotics are antibacterial substances isolated from microbial strains or synthetic origin. Antibiotics act to inhibit or destroy microorganisms. Due to the specific mechanism of each type of antibiotic, there are antibiotics that act on many strains of bacteria, on both gram (-) and gram (+) bacteria, but there are also types that only act on one or several certain strains of bacteria. This limit is called the antibacterial spectrum of the antibiotic.
A broad spectrum antibiotic is a group of antibiotics that act against both gram-negative and gram-positive bacteria or any antibiotic against a wide range of pathogenic bacteria. For example: tetracyclines, phenicols, fluoroquinolones, third and fourth generation cephalosporins … In aquaculture, the most commonly used antibiotic is Cefotaxime, the third generation of Cephalosporin, which has a strong effect per gram (-)
This broad spectrum of antibiotics is often used in cases of bacterial infections but does not indicate the exact cause of the cause or when multiple groups of bacteria are suspected.
Narrow-spectrum antibiotics are antibiotics with good antimicrobial activity against certain strains of bacteria. For example, the natural antibiotic Penicillin only works against the gram (+) group of bacteria, but it does not have a bactericidal effect on the gram (-) bacteria or the Isoniazid antibiotic is only effective against the Mycobacterium tuberculosis strain. It is important to know what causes of the disease from which bacteria can be used effectively.
- Strength of antibiotics
After entering the body, the antibiotic will dissolve in molecular size (unit Ångström, 1 ångström (Å) = 10−10 meters = 10-4 microns = 0.1 nanometers compared to nano-silver from 10 -100 nanometer makes it 100-1000 times smaller). Because of such small size, the antibiotic will enter the bloodstream and circulate throughout the body, to the target organ, thereby destroying or inhibiting pathogenic bacteria.
- Weakness of antibiotics
+ After entering the bloodstream throughout the body, the antibiotic will return to the liver. The liver considers antibiotics to be toxic and is responsible for converting them into non-toxic substances, easily soluble in water and then eliminated by the body. Antibiotics can cause 3 types of hepatotoxicity: dose-dependent toxicity, individual toxicity and drug allergy. So after taking antibiotics, people often use herbal supplements to restore the liver.
+ An important disadvantage of the antibiotic is antibiotic resistance. As mentioned above, the antibiotic was isolated from bacteria, which means that on a very long DNA segment of the bacteria one finds a gene segment that can inhibit itself, thereby researching and synthesizing the antibiotic. Therefore, when using antibiotics to kill bacteria, as long as 1 live bacteria it will recognize, it will find ways to resist antibiotics, then multiply into thousands and billions of antibiotic resistant ones.
+ Some antibiotic resistance mechanism
- Bacteria try to rearrange the nucleotides themselves so that the antibiotic cannot recognize it, thus losing its effectiveness.
- he bacteria can secrete enzymes that can inactivate or cleave the antibiotic, rendering it ineffective
- Bacteria Reduces permeability of the membrane surrounding bacterial cells. Certain changes in the bacterial membrane make it harder to pass. In this way, less antibiotics get into the bacteria.
- Bacteria can form pumps located in their membranes or cell walls. These so-called flow pumps are very common in bacteria and can transport a wide variety of compounds such as signaling molecules and nutrients. Some of these pumps are also able to transport the antibiotic out of the bacteria, in this way reducing the concentration of the antibiotic inside the bacterial cell.
What is silver nanoparticle, the bactericidal mechanism of nanosilver like?
- Advantages of nano silver
+ Nanosilver particles have a wide bactericidal spectrum that can kill both gram (-) and gram (+)
+ Nanosilver itself has very low toxicity or no toxicity, so it does not stress fish.
In an in vivo experimental study (feeding nano silver as an antimicrobial additive to shrimp at concentrations of 10 ppm, 100 ppm, 1000 ppm and 10,000 ppm showed that a concentration of 10-100 ppm did not affect the rate). Survival, feed conversion rate, and at concentrations of 1000 -10,000 ppm suggest that the shrimp are slightly (but insignificant) stressed.
+ In terms of bioaccumulation in muscle tissue, hepatopancreas, gills … Ag concentration found in hepatopancreas is not surprising, since shrimp is crustacean. So, continuous feeding causes accumulation in hepatopancreas, epidermis from which it is possible to treat diseases caused by bacteria in hepatopancreas. Dietary supplements at high concentrations (1000 and 10,000 ppm) can lead to moderate (invisible) liver damage, but in practice the feed content is only 3-6 ppm insignificant compared to the baby. test number.
+ The half-lives in the gills and hepatopancreas are 4.4 and 9.5 days, respectively. Finally, the amount of Ag accumulated in hepatopancreas and gills was 89 and 99%, respectively, only 14 days after the interruption of supply (ie consumption of feed without NP Ag / AgCl).
- Disadvantages of nanosilver+ Currently, nanosilver has been industrially produced, but the cost is still high, requiring more improvements in technology but still meeting safety and efficiency issues.+ The bactericidal spectrum of nanosilver is wide so in addition to killing harmful bacteria, it also kills beneficial bacteria. It is imperative that probiotics supplement with probiotics (Food is also a source of beneficial bacteria). Providing beneficial probiotics to improve gut microbiota, beneficial microorganisms help compete for nutrition with harmful bacteria, increasing the resistance of shrimp. In addition, beneficial microorganisms are symbiotic with the host (beneficial microorganisms synthesize beneficial vitamins that the host body (shrimp) absorbs that vitamin).
Yun’an Qing, Lin Cheng, Ruiyan Li, Guancong Liu, Yanbo Zhang, Xiongfeng Tang, Jincheng Wang, He Liu, Yanguo Qin