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Kimchi LAB Strains that defeat phage infection

Posted on by Raphael Hans

When you talk about fermented foods, kimchi stands out not only as a culinary delight but also as a treasure trove of microbial wonders. One might typically view viral resistance in bacteria as a cause for concern, as it may halt therapy. In the context of kimchi, this resistance shines brightly, enhancing the culinary experience with its remarkable flavors. These bacteria play a crucial role in fermenting kimchi, making them essential for its production. If these bacteria were to be attacked by bacteriophages, the entire process of kimchi production could come to a standstill or reduce production, depriving us of the delightful flavors that make kimchi a culinary delight.

Produced through low-temperature fermentation without pre-sterilization, kimchi hosts a diverse microbial community, shaping its unique flavors and textures. Researchers at the World Institute of Kimchi have delved into this microbial universe, uncovering fascinating insights into the dominant lactic acid bacteria (LAB) species that safeguard kimchi against viral invasions.

In a pioneering study published in the journal Food Microbiology, scientists explored long-term fermented kimchi stored at low temperatures, collecting samples from various regions in South Korea. Their meticulous analysis revealed a specific LAB strain, Pediococcus inopinatus, as the stalwart defender in over 88% of the studied kimchi samples. What sets P. inopinatus apart is its well-developed clustered regularly interspaced short palindromic repeats (CRISPR) system, a sophisticated prokaryotic adaptive immune system that combats phages, and viruses that infect and replicate within bacteria.

Bacteriophages: The microscopic enemy of the dairy industry

Through whole-genome sequencing analysis, the researchers unearthed the unique genetic traits of P. inopinatus. This exceptional LAB strain boasts an abundance of the csa3 gene, responsible for the transcription factors that activate cas genes. Consequently, P. inopinatus stores a wealth of genetic information about phages, enabling it to fend off viral invasions effectively. After the initial phage infection, P. inopinatus becomes adept at preventing subsequent infections, ensuring the stability of the kimchi fermentation process.

This research not only sheds light on the intricate microbial dynamics within kimchi but also paves the way for future studies exploring the broader implications of these findings. As the world continues to grapple with viral challenges, the humble kimchi emerges as a source of inspiration, offering valuable lessons in microbial resilience and antiviral defense mechanisms. The microbial guardians of kimchi, particularly P. inopinatus, stand as a testament to nature’s ingenuity, reminding us of the boundless wonders that the microbial world has to offer.

To read more please visit Mun, S. Y., Lee, W., Lee, S. Y., Chang, J. Y., & Chang, H. C. (2024). Pediococcus inopinatus with a well-developed CRISPR-Cas system dominates in long-term fermented kimchi, Mukeunji. Food Microbiology, 117, 104385.

Mycovirus Halts Vomitoxin Production in Scab Fungus

Posted on by Raphael Hans

A team of scientists from the Agricultural Research Service (ARS) and South Dakota State University (SDSU) has discovered an extraordinary virus that could deal a devastating blow to a notorious fungal menace wreaking havoc on small-grain crops such as wheat and barley.

Enter the formidable enemy: Fusarium graminearum, the malefactor responsible for a devastating plant disease known as Fusarium head blight or “scab.” This nefarious fungus, left unchecked, mercilessly ravages crops, causing substantial reductions in both yield and grain quality. To add insult to injury, under wet and humid conditions, the scab fungus releases a deadly toxin called deoxynivalenol, more ominously known as vomitoxin. This insidious toxin infiltrates the grain, reducing its market value or, in severe cases, leading to outright rejection based on its intended use.

Vomitoxin is also a malevolent trichothecene mycotoxin, which emerges as a formidable adversary in the realm of mycotoxins that infest our grains and forages. Unlike its more overtly sinister counterparts, vomitoxin reveals itself subtly, causing a chilling reduction in feed intake and a haunting decline in performance. This insidious mycotoxin penetrates the core of its victims, manipulating their central nervous systems. While not a known carcinogen like aflatoxin, vomitoxin still wreaks acute havoc, necessitating the consumption of copious amounts of contaminated grain to succumb to its toxic grasp. Chronic exposure poses an uncertain veil obscuring its long-term effects. Livestock and farm animals suffer its tyranny, experiencing weight loss and refusal to consume feed as vomitoxin stealthily infiltrates their sustenance.

But now, a glimmer of hope shines on the horizon. The intrepid scientists from the ARS Application Technology Research Unit and SDSU have unearthed a natural virus, known as a mycovirus, that disrupts the vomitoxin-producing machinery of the scab fungus.

Fungal viruses: Are they ideal antifungal agents?

In the intricate dance of nature, this mycovirus, specifically Fusarium graminearaum Vg1, infects the scab fungus, replicating within it and spreading further. However, the newly discovered strain of mycovirus, aptly named F. graminearum Vg1-SD4, takes the battle against scab to a whole new level by rendering the fungus incapable of producing vomitoxin—an unexpected boon for wheat plants.

Laboratory and greenhouse experiments have proven nothing short of extraordinary. The scab fungus cultures infected with the mycovirus strain exhibited stunted growth and, astonishingly, failed to produce any vomitoxin in the grain of susceptible potted wheat plants. In stark contrast, wheat plants exposed to mycovirus-free scab cultures yielded grain containing a staggering 18 parts per million (ppm) of vomitoxin—a dangerous byproduct detrimental to both livestock and human health.

Dr. Shin-Yi Lee Marzano, an exceptional molecular biologist from ARS, and her brilliant collaborators paved the way for this game-changing revelation. Through meticulous sequencing of the mycovirus’s genetic makeup, they discerned subtle variations from its “parent” species, FgVg1, which had been maintained in a live culture of the scab fungus for nearly a decade, representing a treasure trove of scientific knowledge.

While Dr. Marzano prudently acknowledged that their research, documented in the esteemed July 2022 edition of Microorganisms, remains in its nascent stages, the potential implications are undeniably immense. With further investigation, this extraordinary mycovirus strain could evolve into a biological control agent, formulated and expertly sprayed onto vulnerable wheat varieties and other small-grain crops. This breakthrough solution holds the promise of sparing farmers from incurring crippling losses due to scab infestation and the consequent contamination of grain, destined for both animal and human consumption.

Bimal Paudel and Yang Yen, esteemed experts from SDSU’s Department of Biology and Microbiology, along with Connar Pedersen (formerly of SDSU and now ARS), have played pivotal roles alongside Dr. Marzano in unraveling the secrets of this mycovirus strain, propelling us ever closer to a sustainable, scab-free agricultural future.

As we witness the dawning of this epochal discovery, the realm of agriculture stands on the cusp of a remarkable transformation. Nature’s virus warriors, armed with their devastating mycovirus allies, may soon usher in an era of unparalleled crop protection, safeguarding our precious wheat, barley, and other small-grain crops from the clutches of scab. It is a testament to the ingenuity of human curiosity and scientific endeavor, reminding us that solutions to our most formidable challenges often lie hidden in the intricacies of the natural world.

Tiny Soldiers to the Rescue: Bacteriophage Spray Offers New Solution to Food Contamination

Posted on by Raphael Hans

Every year, the U.S. Food and Drug Administration (FDA) issues a recall list filled with contaminated items that cause multiple foodborne illnesses, ranging from romaine lettuce to frozen falafel, due to the presence of Escherichia coli (E. coli). E. coli is responsible for an estimated 265,000 annual infections in the United States, according to the Centers for Disease Control and Prevention (CDC). To reduce outbreaks and disinfect food, researchers at McMaster University have developed a spray made up of bacteriophages, or phages, which are viruses that cannot infect human cells but can infect and destroy bacteria.

The researchers linked the bacteriophages to create microscopic beads, each about 20 microns in diameter. Together, they linked half a million bacteriophages to make each bead and constructed a community of 13 billion bacteriophages (is this cocktail or super cocktail?). The bacteriophage spray was tested on romaine lettuce and beef steaks contaminated with E. coli O157:H7, a strain of the bacteria that causes severe intestinal infections and often infects lettuce and meat. The bacteriophage spray reduced the E. coli O157:H7 by 6 logs or 99.9999%.

Food poisoning bacteria on fork
credit Center for Science in the Public Interest

The bacteriophage spray is safe to use on food and does not change the taste, texture, or quality of the food. Bacteriophages are specific and only harm the target bacteria while leaving beneficial bacteria alone. Bacteriophages have been recognized as safe since 1958 by the FDA, and they are already being used in products ranging from animal feed to pet food.

The bacteriophage spray has many potential uses, such as modifying it to destroy other types of bacteria, including Salmonella and Listeria, that frequently contaminate food. It can also be used in commercial applications for food harvesting, processing, and packaging. Grocery stores can spray produce on store shelves with bacteriophages in addition to water, and bacteriophages can be added to household disinfectant products that can decontaminate everything from fresh lettuce to fruits.

Bacteriophages have the potential to reduce global foodborne diseases and save lives. The World Health Organization (WHO) estimates that 600 million people become sick after eating contaminated food, and 420,000 people die every year. Children under the age of five account for almost one-third of all illnesses, with 125,000 dying every year.

Bacteriophages: The microscopic enemy of the dairy industry

Posted on by Raphael Hans

The majority of people relate viruses with diseases that affect plants and animals only, what we don’t know is that being the smallest living entity in the universe, viruses are capable of infecting other microorganisms like bacteria. Having viruses affecting bacteria has proven to be beneficial to the human race, especially in recent years where there was a rise in antibiotics resistance and they are used as antibiotics alternatives. These viruses are known as bacteriophages and sometimes termed as phages in short form, these entities are of variety and infect every kind of bacteria that has so far been discovered by scientists while maintaining their specificity (meaning every bacteria has got a certain variety of phages that can specifically infect its strain). Bacteria being well known for their diseases doesn’t mean all of them cause one, and in fact, we have a lot of bacteria that are beneficial to our lives either direct or indirect. Just to mention a few some bacteria help in nitrogen fixation in plants, decomposition, act as normal flora on our skins and stomachs and some are even used in food processing.


Lactic acid bacteria (LAB) are among the most beneficial microorganisms in the food industry. These microorganisms produce lactic acid from sugar fermentation. For this reason, they have been used for thousands of years in the production of fermented milk products, like yogurt and cheese, among others. Just like other bacteria, they are also prone to attacks, phages penetrate their genetic materials and command the bacteria to act as a piece of machinery for making viral copies before the cell burst and die off to release new particles.
Dairy products. photo by Change food

Effect of Lactic Acid Bacteria on milk during processing

The LABs trigger a microbial process where they transform the –sugar in milk- into lactic acid. That acid modifies the structure of the milk proteins making them curdle and reproducing the same effect on the product’s texture. Besides, it provides the milk with that characteristic slightly bitter taste. It was proved that these microorganisms provide beneficial effects on the health of those who consume them. Furthermore, it supplements the health of the bacterium present in the intestinal flora promoting the good performance of the digestive system. For this reason, they are very important for the dairy industry considering the context of growing interest in the market of probiotic products.


Effect of phage on the action of Lactic Acid Bacteria (LAB) during milk processing

Phage activity causes decreased starter (Starter is a set of LAB bacteria that are readily available to initiate the fermentation process) activity in cheese and fermented milk manufacturing, resulting in fermentation in which acid production is markedly reduced or, in extreme cases, totally blocked. This failure in fermentation develops low-quality products that are not safe from a microbiological point of view because they can contain contaminants and/or pathogens that do not have to compete with the lactic bacteria that protect the product (probiotic way).


Where is the source of phage contamination in the dairy industry?

Raw milk is considered to be the principal source of phages, either as free virions or as prophages present in wild strains of lactic acid bacteria (LAB), and constitutes the primary phage entranceway to the industrial environment. Sometimes equipment, people, and the environment can be the source of contamination although this kind of contamination is much easier to handle just by modifying sanitation procedures and decontaminating surfaces.

Methods used to inactivate Dairy Bacteriophages contaminants

Phages are difficult to eliminate because they rapidly disseminate in dairy plants. The following are commonly used methods in eliminating phage contaminants in dairy processing plants.


  1. Heat Treatments

Most dairy processing plants use heat to kill a number of microbes from milk, among others phages are heavily affected especially when subjected to the high heat of 70°C for a long time. The conditions recommended by the International Dairy Federation (IDF; 90°C for 15 min) to guarantee complete phage inactivation. For cheese production, low-temperature long time (LTLT, 63°C for 30 min) or high-temperature short time (HTST, 72°C for 15 s) pasteurization were traditionally applied. Ultra-high-temperature (UHT) processing, also called ultra-pasteurization (more than 135°C for 1–2 s), is a sterilization treatment as it produces spores destruction. However, this high heating can cause Maillard browning and negatively affect the taste and smell of dairy products. The milk used for yogurt production is generally treated at 80°C for 30 min or at 95°C for 10 min. Regardless of the high efficiency of this heat treatment to inactivate microorganisms, it is not always effective against dairy bacteriophages.

  2. Chemical treatment (Biocides)

A biocide should fulfill several criteria to be usable in the food industry, for example possessing a fast antimicrobial activity, ease of application, low cost, lack of negative impact on the final product, and degradation into harmless final products. However, the inactivation of bacteriophages was taken into consideration only recently as a criterion of biocides selection, which is reflected by an increasing number of studies directed to quantify their effectiveness in this sense. Ethyl alcohol (ethanol), isopropyl alcohol (isopropanol), sodium hypochlorite, and peracetic acid are among the most common biocides.


  3. High-Pressure Treatments

High-pressure processing is one of the most promising because it combines maximal retention of the chemical and physicochemical product properties with efficient germ reduction. The most studied and applied pressure-based processes are high hydrostatic pressure (HHP) and high-pressure homogenization (HPH). HPH is a high hydrodynamic process during which the fluid is forced to pass through a small orifice and then subjected to an ultra-rapid decompression. The sudden fall in the local pressure of the fluid at constant temperature leads to the nucleation and growth of vapor bubbles (or cavities) within the body of liquid, the collapse of which could transmit several localized forces to surfaces or particles, including the microbial cell.


  4. Photocatalysis

Photocatalysis is a process in which light energy is used to drive pairs of chemical reactions. This method is well utilized if phage particles are aerosolized in the air. The capability of bacteriophages to remain in the air for long periods makes bioaerosols one of the most important dispersion routes of virions. 

In the mid-1930s, the first adverse impact of bacteriophages on dairy fermentation was reported. Despite sanitary precautionary measures, starter strain rotations, and the persistent development of new phage-resistant bacterial strains, phages continue to be one of the most common and economically significant causes of fermentation failure. Bacteriophages cause problems in industrial dairy fermentations all over the world due to their natural presence in the milk environment. They are difficult to eradicate due to their short latent period, relatively large burst size, and/or resistance to pasteurisation. Phage-induced bacterial cell lysis causes failed or slow fermentation, a decrease in acid production, and a reduction in milk product quality (nutritive value, taste, texture, and so on), resulting in significant economic losses.

 References

  • Role of Bacteriophages in the Implementation of a Sustainable Dairy Chain by Gutierez et al, (2019)
  • Review: efficiency of physical and chemical treatments on the inactivation of dairy bacteriophages by Guglielmotti et al, (2012).
  • Marcó, M. B., Suárez, V. B., Quiberoni, A., & Pujato, S. A. (2019). Inactivation of Dairy Bacteriophages by Thermal and Chemical Treatments. Viruses, 11(5), 480. https://doi.org/10.3390/v11050480
  • Lactic Acid Bacteria Resistance to Bacteriophage and Prevention Techniques to Lower Phage Contamination in Dairy Fermentation by Szczepankowska et al, (2013).

Unlocking Food Safety with Bacteriophages: A Natural Solution for Food Safety

Posted on by Raphael Hans
Food safety is an important issue in our society. With the rise of bacteria-related illnesses, it is essential to know how to protect ourselves and our families from these dangerous microorganisms. One way to do this is to use bacteriophages, which are tiny viruses that can kill bacteria. In this blog post, we will explore what bacteriophages are, the benefits they offer, how they can be used to improve food safety, and more.

Creator: fcafotodigital | Credit: Getty Images

What are Bacteriophages?

Bacteriophages (or phages) are viruses that infect and replicate inside bacterial cells. They are the most abundant life forms on Earth, with an estimated 10^31 of them existing in the environment. Phages are composed of genetic material (DNA or RNA) surrounded by a protein coat. They vary in size, shape, and structure, but all are small enough to be invisible to the naked eye.

Phages have been around for millions of years and have played an important role in our evolution. For example, they have been used to control bacterial infections in humans since the early 1900s and have even been used to develop vaccines. In recent years, they have become an important tool in food safety research.

The Benefits of Bacteriophages

Phages have many advantages over traditional antibiotics. First of all, they are specific to the bacteria they target, meaning they only kill the bacteria they are designed to attack. This makes them much safer than antibiotics, which can have a range of unwanted side effects. Secondly, phages can be used to target antibiotic-resistant bacteria, which traditional antibiotics may not be able to do. Finally, phages are natural and can be safely used in food production.

Phage Types: Lytic and Temperate

Phages are divided into two main types: lytic and temperate. Lytic phages are the most common type and have a life cycle that involves injecting their genetic material into the bacterial host and then replicating inside it. The phage then lyses (or breaks open) the host cell, releasing the new phage particles. This type of phage is the most effective for killing bacteria.

Temperate phages, on the other hand, do not always lyse the host cell. Instead, they can integrate their genetic material into the host cell’s DNA, forming a prophage. The prophage can then remain dormant in the host cell for long periods of time. This type of phage is useful for studying how bacteria evolve and develop resistance to antibiotics.

Phage Life Cycles

The life cycle of a phage can be divided into three stages: attachment, replication, and release. In the attachment stage, the phage attaches itself to its bacterial host using special proteins on its outer surface. In the replication stage, the phage injects its genetic material into the host cell and begins to reproduce. Finally, in the release stage, the phage particles are released from the host cell, either through lysis or through the cell’s normal cellular processes.

Phage Therapy

Phage therapy is a form of treatment that uses phages to target and kill pathogenic bacteria. It has been used for decades to treat bacterial infections but has recently gained attention as a potential alternative to antibiotics. In phage therapy, phages are used to target and kill specific bacteria, while leaving beneficial bacteria unharmed. This makes it a safer and more effective treatment than antibiotics, which can have unintended side effects.

Phage Banks and Phage Therapy

The use of phage therapy requires the availability of a large number of phages that can be used to target different kinds of bacteria. To meet this need, phage banks have been established, which store and distribute phages that can be used for phage therapy. These banks are a valuable resource for researchers and clinicians who are looking for phages to use in their treatments.

Phage Therapy vs. Antibiotics

When it comes to treating bacterial infections, phage therapy has several advantages over antibiotics. First, phages are highly specific, meaning they only target the bacteria they are designed to attack. This makes them a safer and more effective treatment than antibiotics, which can have unintended side effects. Secondly, phages can be used to target antibiotic-resistant bacteria, which traditional antibiotics may not be able to do. Finally, phages are natural and can be safely used in food production.

Clinical Trials and Medicinal Products

Clinical trials are an important part of developing phage-based medicinal products. These trials are used to evaluate the safety, efficacy, and long-term effects of phage therapy. They are also used to compare phage therapy to other treatments, such as antibiotics, to determine which is more effective.

Phage-based medicinal products have been approved for use in humans and animals in several countries, including the USA, Canada, and European countries. These products are used to treat bacterial infections, including those caused by Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa.

Quality Control and Bacterial DNA

Quality control is an important part of using phages for food safety. Phages must be tested for their ability to target and kill the specific bacteria they are designed to attack. This requires the use of advanced sequencing techniques, such as DNA sequencing, to identify the genetic elements of the phages.

In addition, quality control involves screening the phage for the presence of undesirable genes such as those coding for virulence and antimicrobial resistance. This helps ensure that the phage does not introduce any unwanted genetic material into the host cell. This is especially important when using phages to treat food-borne illnesses, as it helps to ensure that the food is safe to consume.

Target Bacteria and Host Range

When selecting phages for food safety, it is important to consider the target bacteria and the host range. The target bacteria are the bacteria that the phages are designed to target and kill. It is important to select phages that are specifically designed to target the bacteria of concern.

The host range is the range of bacterial hosts that the phage can infect. It is important to select phages that can infect a wide range of bacterial hosts, as this will increase the effectiveness of the phage therapy.

Genetically Modified Phages

Genetically modified phages are phages that have been engineered to target specific bacteria. This allows for more precise targeting of the bacteria of concern. In addition, genetically modified phages can be used to deliver genetic material, such as proteins or DNA, to the bacterial host. This can be used to modify the bacteria or to detect the presence of a specific gene. They can also be employed as reporter phages to monitor the spread of specific bacteria, allowing them to be used to monitor food contamination.

Bacteriophages and Food Safety

Bacteriophages are an important tool in food safety research. Phages can be used to target and kill specific bacteria while leaving beneficial bacteria unharmed. This makes them a safer and more effective treatment than antibiotics, which can have unintended side effects. In addition, phages can be used to detect and monitor the presence of specific bacteria in food products, allowing for more precise quality control.

Bacteriophages and Antibiotic-Resistant Bacteria

The emergence of antibiotic-resistant bacteria is a growing concern in the food industry. Phages, however, can be used to target and kill these bacteria, making them an important tool in the fight against antibiotic-resistant bacteria. Phages can also be used to monitor the presence of antibiotic-resistant bacteria in food products, allowing for more precise quality control.

Bacteriophages are a powerful tool in the fight against food-borne illnesses. They are natural, highly specific, and can be used to target and kill specific bacteria, while leaving beneficial bacteria unharmed. In addition, phages can be used to detect and monitor the presence of specific bacteria in food products, allowing for more precise quality control. For these reasons, phages offer a natural and effective solution for food safety. Try some of the phage products available on Amazon to see for yourself.

Phage technology can help to fight food poisoning

Posted on by Raphael Hans
Food poisoning has recently dominated the terror world; some major news outlets reported that some pathogens are unstoppable even in first-world countries such as the United States of America (USA). According to the CDC report, Salmonella is one of the leading causes of food poisoning in the United States, sickening an estimated 1.35 million Americans each year and resulting in approximately 26,500 hospitalizations and 420 deaths. Although chemical washes have been used, experts state unequivocally that the wash does not eliminate all bacteria from the food. The world needs to develop an alternative method for efficiently decontaminating food before consumption.
Phages can be used to decontaminate bacteria in food
Bacteria in food

What is food poisoning?

Food poisoning, also known as foodborne illness, is caused by eating food contaminated with infectious organisms such as bacteria, viruses, and parasites. Their toxins are the most common causes of food poisoning. According to the American Centre for Disease Control and Prevention (CDC), many food poisoning agents are bacteria like Clostridium botulinum, Listeria, Staphylococcus aureus, Vibrio sp Salmonella, Escherichia coli, and Campylobacter. The severity of the illness is largely determined by the affected organ and the agent of concern, as some can result in death if a patient is left unattended. Because the agents responsible for food poisoning mentioned above are bacteria, phages may be an excellent candidate for inhibiting their growth and thus preventing food poisoning.

Symptoms of food poisoning

Food poisoning symptoms, which can appear within hours of eating contaminated food and can last for days, frequently include:
  • Nausea
  • Vomiting
  • Diarrhea
  • Stomach cramps
  • Fever
  • Stomach upset
 Food poisoning is often mild and resolves without treatment, but in some cases, it can be life-threatening and will need urgent care.

How can phage be used to stop food poisoning?

Bacteriophages can be directly applied to food; their stability and efficiency in “cleaning up” the bacteria of the target in food can be exceptional. These particles have the ability to inhibit the growth of bacteria that cause poisoning. Before applying phage to food, scientists conduct all necessary tests to ensure that the phage will be safe and stable under the conditions in which the food will be stored. Some phages can cause the transfer of Antibiotic resistance Genes from one bacteria to another; scientists screen for all the genes related to the transfer.

Why phages are a better option for fighting food poisoning?

Bacteriophages offer several advantages that traditional methods couldn’t afford to provide.
  1. Bacteriophages are fresh food-friendly. The most recommended method involves heating or cooling food to kill or inhibit the growth of food poisoning pathogens; these methods may limit the consumption of fresh food like vegetable salads and fruits.
  2. They can multiply to kill the invaders. This phenomenon is also known as auto dosing; once applied, phages will keep infecting and multiplying.
  3. Ability to crystalize until the pathogen is encountered. Like a virus, phage didn’t spare some extraordinary characters like crystalizing, hence increasing their duration to the area.
  4. They cause no harm to humans, plants, and animals (I wrote an article on the possibility of bacteriophage infecting a human cell).
  5. Ability to mutate in response to phage-resistant strains. Some studies reported that phages can mutate much faster compared to bacteria.
  6. Cause no change of taste, texture, or color to the food.
  7. Phages can be used to decontaminate solid surfaces like utensils and tops

Bacteriophages could be used in medicine and the food industry. For many years, scientists have been researching the use of phages in the eradication of foodborne pathogens and the prevention of food poisoning. Hopefully, this technology will be applied on a large scale.

Can phage be used as a bio preservative for fish?

Posted on by Raphael Hans

fish preservation
Fish preservation

Bacteriophage as a bio preservative

Bacteriophagesfit in the class of natural antimicrobial and their effectiveness in controlling bacterial pathogens in the agro-food industry has led to the development of different phage products already approved by USFDA and USDA. The majority of these products are to be used in farm animals or animal products such as carcasses, and meats, and also in agricultural and horticultural products. Treatment with specific phages in the food industry can prevent the decay of products and the spread of bacterial diseases and ultimately promote safe environments in animal and plant food production, processing, and handling. This is an overview of recent work carried out with phages as tools to promote food safety, starting with a general introduction describing the prevalence of foodborne pathogens and bacteriophages and a more detailed discussion on the use of phage therapy to prevent and treat experimentally induced infections of animals against the most common foodborne pathogens, the use of phages as biocontrol agents in foods, and also their use as bio-sanitizers of food contact surfaces.

Charting the Path to Food Safety

Bacteriophages are viruses that infect bacteria but are not harmful to humans, animals, or plants. Since their discovery in 1915, phages have been widely used not only in human and veterinary medicine but also in a variety of agricultural settings. Phages, as obligatory parasites, can cause cell lysis to release newly formed virus particles (lytic pathway) or lead to the integration of genetic information into the bacterial chromosome without causing cell death (lysogenic pathway).

In terms of food safety, strictly lytic phages may be one of the most harmless antibacterial approaches available when compared to conventional antibiotics that cause resistance.


Phages offer advantages as biocontrol agents for several reasons: 

  1. High specificity to target their host is determined by bacterial cell wall receptors, leaving untouched the remaining microbiota, a property that favors phages over other antimicrobials that can cause microbiota collateral damage; 
  2. Self-replication and self-limiting, meaning that low or single dosages will multiply as long as there is still a host threshold present, multiplying their overall antimicrobial impact;
  3.  As bacteria develop phage defense mechanisms for their survival, phages continuously adapt to these altered host systems; 
  4. Low inherent toxicity, since they consist primarily of nucleic acids and proteins; 
  5. Phages are relatively cheap and easy to isolate and propagate but may become time-consuming when considering the development of a highly virulent, broad-spectrum, and non-transducing phage; 
  6. They can generally withstand food processing environmental stresses (including food physiochemical conditions); 
  7. They have proved to have a prolonged shelf life. Phages are readily abundant in foods and have been isolated from a wide variety of raw products (e.g., beef, chicken)

Are there phage products for food preservation?

Several products are already on the market to ensure food safety with minimal environmental impact. In the food and feed industries, phages are a clean label alternative for antibiotic preservation. Furthermore, antibiotic restrictions in animal husbandry, as well as customer perception, have led to the use of natural preservatives. In food safety and production, the bacteriophage is a natural antimicrobial with a narrow spectrum. When using bacteriophage as a preservative, the following steps must be taken:


Despite the availability of a variety of those products, few to no products were prepared to preserve one of the most perishable foods. Because fish spoil easily, an immediate solution is required to reduce post-harvest losses. The approval of phage products remains a threat to scientists around the world. Despite the barriers and limitations, governments continue to rely on old ways of doing things and do not place enough faith in phage technologies.

Fish is one of the world’s healthiest foods. It is high in essential nutrients such as protein and vitamin D. Fish is also the best source of omega-3 fatty acids, which are essential for your body and brain. Fish is an excellent source of omega-3 fatty acids and vitamin D. A healthy community will be ensured by preserving this food in a safe manner.