Streptococcus salivarius is a Gram-positive, non-pathogenic bacterium naturally found in the oral microbiota of healthy individuals. It is recognized as an effective probiotic due to its antimicrobial properties and ability to stimulate the immune system, particularly activating natural killer (NK) cells and producing anti-tumor cytokines such as interferon-gamma and interleukin-12 (IL-12). Strains K12 and M18 of this bacterium are specifically used to combat harmful oral bacteria and prevent tooth decay. These strains act by producing bacteriocins, especially against Streptococcus mutans (the main cause of tooth decay). Probiotics, in general, are live microorganisms that, when consumed in sufficient amounts, have beneficial effects on the host's health. Streptococcus salivarius, as a probiotic, plays a role not only in oral and dental health but also in improving overall body health. Studies have shown that this bacterium can help reduce bad breath, improve gum health, and reduce dental plaque formation. Additionally, the use of products containing this probiotic, such as toothpaste and mouthwash, can help its effective colonization in the oral cavity. Compared to conventional methods such as the use of antibiotics, probiotics are safer and reduce the risk of microbial resistance. However, probiotic consumption may cause mild side effects such as bloating or diarrhea in some individuals. Overall, Streptococcus salivarius as a promising probiotic plays an important role in maintaining oral and dental health and improving the quality of life.
The area of Biotechnology has been both interesting and surprising from the beginning. At first, the scientists were filled with apprehension regarding the cessation of this technology's usage. It is more prudent to be cautious when making alterations to nature as the resulting outcomes remain unpredictable. Utilizing this innovative technology to enhance the nutritional value of food and combat illnesses is a logical approach. The process of creating GMOs involves extracting specific genes from one organism and inserting them into a different organism to generate modified living entities. This process usually gives the new organism specific traits that we want it to have. GMOs can be plants, animals, or enzymes that have been genetically modified. Some genetically modified organisms (GMOs) have been given permission by government agencies to be used for business and to be eaten, while others are still being reviewed by these agencies. Some GMOs are still being tested in laboratories. Genetic modification or genetic engineering of organisms can be put into groups: Green genetic engineering, also known as agro-genetic engineering, is all about creating genetically modified plants for use in farming and food production , Genetic engineering in red/yellow is used in medicine, tests for genetics, and gene therapy, as well as to make drugs like insulin and vaccines , Bacteria or yeast: These micro-organisms are created by changing their genes to make them produce specific chemicals. The chemicals they produce are used in industries to make things like medicine or other products.
Objective: Acinetobacter baumannii is a pathogenic bacterium with clinical attributes of nosocomial infection and resistance to antibiotics. Phage therapy represents a potential solution because it can specifically target MDR strains. This study aimed to isolate and characterize a lytic bacteriophage specific to A. baumannii, evaluate its kinetic and lytic properties, and investigate the effects of laser treatment on enhancing phage antibacterial activity against multidrug-resistant clinical isolates. Methods: Clinical specimens were collected from patients in three hospitals in Al-Diwaniyah, Iraq, and A. baumannii isolates were identified using standard biochemical tests, API systems, and 16S rRNA PCR sequencing. Environmental samples were screened to isolate lytic phages, which were propagated, purified, and analyzed using plaque assays and scanning electron microscopy. Phage kinetics—including adsorption rate, eclipse period, lysis time, and burst size—were assessed using standard bacteriophage quantification methods. Laser treatment was applied to evaluate its effect on phage activity under different temperatures and pH conditions. Results: A lytic phage specific to A. baumannii was successfully isolated, exhibiting an icosahedral head and a long tail typical of virulent phages. The phage showed rapid adsorption, a short eclipse period, and a high burst size (~111 phages per infected cell). It demonstrated strong lytic activity at temperatures between 35–45 °C and pH 8–10.5. Laser exposure, at 250 pulses, significantly enhanced phage antibacterial activity, resulting in faster bacterial lysis and increased phage productivity. Conclusions: The combination of phage therapy and laser treatment represents a promising strategy for combating MDR A. baumannii