Modification of the gut microbiota by beneficial microbes can enhance an organism’s lifespan, giving rise to the concept of probiotics. Probiotics are live microorganisms that provide health benefits when taken in sufficient amounts. Owing to their outstanding health benefits, probiotics have experienced rapid expansion and gained interest for the development of new applications. The exploration of microbial applications via genetic modification is currently of great interest to researchers. Genetic engineering using the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas system has received considerable attention and has established applications. Owing to these enhanced properties, the CRISPR-Cas system is currently used in medicine, agriculture, food, and biotechnology. Considering the adaptive immune system in bacteria, this genetic tool is used to alter the microbial genome. Lactic acid bacteria (LAB) are widely recognized for their probiotic potential, and over 40% of LAB species contain the CRISPR-Cas system. The rising demand for probiotics and their expanding applications necessitate the enhancement of their existing characteristics. The CRISPR-Cas system, recognized for its precision, accuracy, and speed, has enabled researchers to modify the genomes of probiotics, thereby enhancing their beneficial attributes. This system can enhance probiotic properties through additive, subtractive, or modulatory mechanisms. Various approaches have been developed to improve probiotic functionalities using the CRISPR-Cas system, such as substituting slow promoters with efficient alternatives, eliminating undesirable components, boosting metabolism, and increasing tolerance levels. Furthermore, CRISPR-engineered probiotics have emerged as next-generation probiotics with enhanced properties and advanced applications across diverse fields, including the food, medicine, agriculture, and pharmaceutical sectors.

The rapid rise of multidrug-resistant (MDR) pathogens poses a major challenge to global healthcare, reducing the effectiveness of conventional antimicrobial therapies and necessitating innovative treatment strategies. Probiotics have emerged as promising biotherapeutic agents due to their ability to modulate the gut microbiome, inhibit pathogen colonization, produce antimicrobial compounds, and enhance host immunity. Recent advances suggest that integrating probiotics with nanotechnology and artificial intelligence (AI) may provide a powerful approach to combat MDR infections. Nanotechnology-based delivery systems improve probiotic stability, gastrointestinal survival, controlled release, and targeted delivery, thereby enhancing therapeutic efficacy. Meanwhile, AI-driven tools facilitate microbial profiling, strain selection, resistance surveillance, predictive modeling, and formulation optimization. The convergence of probiotics, nanotechnology, and AI offers a personalized and adaptive strategy for preventing and managing MDR infections while minimizing the selective pressures that drive antimicrobial resistance. This review highlights the potential of this emerging tri-modal approach as a next-generation solution against MDR pathogens.

Mycobacterium avium subsp. paratuberculosis (MAP), the causative agent of Johne's disease and a potential contributor to Crohn's disease, presents a significant challenge due to its resistance to conventional antibiotics. This necessitates the development of innovative strategies for prevention and treatment. This study aimed to evaluate the anti-bacterial activity of pathogen-specific antibodies derived from chicken egg yolks (immunoglobulin Y [IgY]) and the postbiotics from lactic acid bacteria against MAP. Immunoglobulin Y antibodies were produced by immunizing hens with formalin-killed MAP strain antigens. The IgY was extracted and purified, and the anti-MAP titers were quantified by indirect enzyme-linked immunosorbent assay. The minimum inhibitory concentration of different concentrations of specific anti-MAP IgY and the mixture of postbiotics (from four different probiotic strains, including Lactobacillus reuteri, Lactobacillus rhamnosus, Lactobacillus acidophilus, and Pediococcus acidilactici) individually and in combination against MAP was determined at various time intervals. Anti-MAP IgY titers in egg yolks increased within 2 weeks of immunization, reaching peak levels at 6 weeks. Growth inhibition assays revealed that postbiotics concentration as low as 6.25 mg mL-1 effectively inhibited MAP growth. Anti-MAP IgY demonstrated anti-bacterial activity with a minimum inhibitory concentration of 50.00 mg mL-1, while the combined IgY-posbiotics treatment achieved MAP growth inhibition at a minimum inhibitory concentration of 3.125 mg mL-1. The findings of the study suggest that combination therapy with specific IgY and postbiotics may be a promising preventive strategy for controlling MAP infections. Further in vivo studies are needed to elucidate the underlying mechanisms and optimize the application of this approach for broader use in veterinary and human medicine.

The mutual association formed between the gut flora and the biological host is pivotal, mainly for drug action. Various examination has spotlighted the potential consequences of the gut microbiome on drug efficacy, revealing its role in controlling metabolism in the body. Furthermore, reciprocal engagement has been examined to investigate how pharmaceutical agents influence the composition of the gut microbiome. This paper emphasizes the intricate relationship between pharmacology and environmental microbiology, directing the extensive significance of pharmaceutical agents on health by controlling the gut microbial consortium. One main highlight of this review is to determine the differences observed in populace as a result of drugs, which is a crucial component in boosting personalized treatment approaches and intensifying therapeutic findings. Apart from their function in drug metabolization, the gut microbiota is disclosed as a source of metabolic products that can alter drug action. These microbially-derived metabolites could notably effect drug results and changes the body’s physical mechanisms. The investigation suggests utilizing metabolomics to disclose the complications of gut microbiota–drug interactions. Several latest analytical strategies provide an effective tool for deciphering the complicated association among microbiome-generated fragments and pharmaceutical products, providing detailed understanding into this interesting connection.

Chronic respiratory disease is considered by reduced airflow and heightened airway inflammation, a pattern that has progressively increased in past few decades. Currently, chronic respiratory disease is considered one of the main leading causes of death worldwide. The gut-lung axis, which connects these two organs, facilitates bidirectional communication and may be influenced by microbiome populations in the context of disease interactions. The human microbiome, particularly in the gastrointestinal tract is thought to play a pivotal role in affecting diseases and maintaining homeostasis. Dysbiosis, defined as an imbalance in the gut microbiota, is associated with an elevated risk of lung infections. Studies have shown that modifying the gut microbiota by the use of probiotics, prebiotics, and synbiotics can reduce the duration and extent of respiratory infections. Probiotics have been observed to significantly alter serum cytokine and IgE levels in allergic conditions, as well as reduce eosinophilia in individuals with asthma. However, there has been no discernible improvement in clinical symptoms, although this approach may diminish eosinophilia in chronic obstructive pulmonary disease (COPD) patients and mitigate serum cytokine and IgE levels. Several factors such as illness severity, treatment duration, patient-specific, environmental characteristics, and treatment regimen seem to influence the effectiveness of these interventions. Research indicates that direct interaction and colonization of respiratory epithelial cells by probiotic microbes can enhance the success of intranasal probiotic delivery compared to oral administration. Although allergic rhinitis is a chronic inflammatory ailment, nasal probiotics have been utilized to address acute infections and respiratory disorders, offering a promising therapeutic avenue for a range of chronic inflammatory conditions.

Infecting to Melissococcus plutonius, the primary cause of the European foulbrood (EFB) disease, can be followed by infecting to the secondary bacteria, such as Enterococcus faecalis and Brevibacillus laterosporus. The aim of this research was to diagnose EFB disease by tracking the causes of the disease in apiaries all over Iran. From 260 apiaries, honey bee samples were randomly collected. After samples preparation, the genomic DNA was extracted and specific primers were selected for interested bacteria. Using the conventional polymerase chain reaction (PCR) method for E. faecalis and B. laterosporus and nested-PCR method for M. plutonius, the target fragments were amplified. Desired standard bacteria and distilled water were used as positive and negative controls, respectively. Results showed that out of 260 samples from apiaries, 74 and three samples were positive for E. faecalis and B. laterosporus bacteria, respectively. Also, the results of nested-PCR showed that 58 samples were positive, of which only 12 samples were positive in the evaluation of E. faecalis. Results demonstrated that the highest and the least levels of the infection for M. plutonius and E. faecalis were in the south and east of the country, respectively. Results indicated that sometimes due to the excessive growth of secondary bacteria, the main bacteria can be removed from the environment. Also, findings proposed that those provinces with higher number of populations, followed by higher amount of air pollution, had more infected samples than others.

Honey bees (Apis mellifera) are among the most crucial pollinators, significantly contributing to the growth of flowers and wild plants within ecosystems. Extensive epidemiological studies have been undertaken to identify and mitigate bacterial, fungal, and viral diseases affecting these insects. American foulbrood (AFB) is a particularly severe and highly contagious bacterial disease that impacts honey bee (Apis mellifera) larvae. This disease is caused by a gram-positive bacterium known as Paenibacillus larvae. This bacterium has the capacity to produce resilient spores that possess the ability to survive for extended periods under conducive environmental conditions. In the absence of a timely diagnosis and subsequent treatment, Africanized honey bees (AFB) have the potential to infect the entire hive and disseminate the infection to neighboring hives. The objective of this research was to assess the prevalence of AFB disease in apiaries nationwide. From autumn to winter of 2022, the study entailed the sampling of adult bees and honey from 266 apiaries dispersed across various regions of the country, encompassing 31 provinces. The preparation of the 532 samples was carried out in accordance with established protocols, and the subsequent DNA extraction process was executed. Two sets of specific primers were employed to identify the P. larvae using PCR and nested-PCR methods. Subsequently, the selected samples that were positive for PCR were subjected to sequencing, and a phylogenetic tree was constructed. The findings indicate that, among the 266 honeybee samples, 14 (5.26%) were positive, and among the 266 honey samples, 42 (15.78%) were positive. Among the 31 provinces that were investigated, P. larvae infection was detected in 18 provinces (61%). The highest incidence of AFB disease was documented in the Northern Provinces (28.78%) and the central regions of the country (25.35%). In contrast, the Eastern Provinces demonstrated the lowest infection rate (5.71%), a finding that was statistically significant. The majority of positive honeybee samples were sourced from the Central Provinces, while the majority of honey samples were from the Northern Provinces. The findings of this study suggest that Afipobacterial fever (AFB) is a prevalent bacterium in apiaries throughout Iran.

The present study aimed to assess the impact of a probiotic supplement on the effectiveness of the Newcastle disease (ND) vaccine in specific pathogen-free (SPF) chickens. A total of one hundred and twenty 7-day-old SPF chicks were randomly divided into six groups including: CNT (control group), PRO (probiotic), RCV (Razi Clone12IR vaccine), ICV (imported Clone vaccine), PRO + RCV (probiotic and Razi Clone12IR vaccine), and PRO + ICV (probiotic and imported Clone vaccine). Administration of the probiotic, either alone or in conjunction with ND vaccination, decreased cholesterol and increased total protein, albumin, calcium, and phosphorus concentrations (P < 0.05). Increasing weight, length, and bone breaking strength were observed in chickens that were given the probiotic alone. The highest concentration of malondialdehyde (MDA) was recorded in the CNT, while MDA levels decreased in the PRO, PRO + RCV, and PRO + ICV (P < 0.05). An increase in IgY anti-SRBC antibody titer was found in the PRO + RCV and PRO + ICV groups. Higher antibody titer against ND was observed in the PRO + RCV (P < 0.05). The use of probiotics during ND vaccination led to increased lysozyme activity compared to other groups (P < 0.05). The birds receiving probiotics exhibited significantly greater villus height, crypt depth, and villus height/crypt depth ratio in the duodenum (P < 0.05). No histopathological lesions were observed in the trachea, lungs, liver, or bursa of Fabricius in vaccinated chickens, regardless of whether they received probiotic dietary supplementation. The study’s findings suggest that incorporating probiotics during ND vaccination can enhance the health-related parameters of SPF chickens.

Lactic acid bacteria (LAB) isolated from camel rumen and traditional dairy products were assessed for their probiotic potentials and exopolysaccharide (EPS) production. EPS were partially characterized, and their safety assessed by hemocompatibility testing in human, sheep, rabbit, and chicken red blood cells. EPS-producing isolates exhibited notable antibacterial activity against Salmonella paratyphi, but showed limited effects against Staphylococcus aureus and Enterococcus faecalis. All isolates demonstrated low resistance under acidic conditions (2.5 and 4.5) with survival rates ranging from 10 % to 60 %, while based on their bile resistance (0.3 % and 0.5 % v/w), they were classified as moderate or high resistant. The isolates showed greater resistance in the simulated intestinal environment compared to the simulated gastric environment, were non-hemolytic, arginine negative, and devoid of antibiotic resistance and other virulence genes. Three high-yield EPS producers; A-1 (Leuconostoc mesenteroides 6), A-3 (L. mesenteroides DN-1), and A-5 (Lacticaseibacillus rhamnosus SK-2), showed yields of 21.95, 18.76, and 1.14 g/L, respectively. Total sugar contents were highest in DN-1 (90.50 %), whereas total protein and phenolic contents were highest in SK-2 (1.35 % and 0.68 mg GAE/mL). The EPS (A1, A3, and A5) harbored significant antioxidant potentials with half-maximal effective concentration (EC50) of 2183, 1983, and 822 μg/mL (p < 0.05), respectively. Even at the highest tested concentrations, the EPS were non-hemolytic confirming their safety. These results highlight the strain-specific EPS characteristics of the LAB isolates, their functional and safety attributes, allowing their possible applicability in functional foods, nutraceuticals, and probiotic formulations.

The food industry is increasingly interested in postbiotics/parabiotics because of their ability to preserve and enhance functional food production. These substances contain several bioactive compounds with immune system-regulating, antimicrobial, antioxidant, prebiotic, and anticancer properties. Despite its potential benefits, incorporating postbiotics/parabiotics into food poses various obstacles that must be overcome. These include technical barriers in production, lack of uniform definitions and regulations, regulatory obstacles, limited consumer awareness and acceptance, quality control challenges, determining the most effective dosage, and cost considerations. This review discusses these challenges and the research progress that has been achieved to address these drawbacks. As research in this field continues to advance, addressing these challenges will be crucial to unlock the full potential of postbiotics/parabiotics in the food industry.

Postbiotics are emerging as promising next-generation probiotics owing to their stability, safety, and multifaceted health benefits. In the present study, the postbiotics from Lactobacillus acidophilus BLAC 258 (LA) and Lactiplantibacillus plantarum BLP 272 (LbP) were analyzed for their antibacterial, antioxidant, anti-inflammatory, other biochemical and safety attributes. The postbiotic fractions (PF) of LA demonstrated potent antagonistic actions against Shigella dysenteriae and Escherichia coli, whereas, PF from LbP were more effective against Bacillus cereus. The combination of the two postbiotics resulted in synergistic antibacterial effects with MIC values of 6.25 mg / ml for Sh. dysenteriae and 12.5 mg / ml for B. cereus and E. coli. The LA postbiotics demonstrated superior antioxidant capacity (58.73 %), TPC (2515 +/- 1.41 mg GAE / L), and TFC (1432.25 +/- 1.450 mg Qu/100 g). On the contrary, LbP post-biotics contained higher total protein (338 mu g/g) compared to LA (226 mu g/g) (p < 0.05). A dose-dependent anti-inflammatory response was observed for both postbiotics by inhibiting albumin denaturation and heat-induced hemolysis. During metabolic profiling, 16 major constituents were observed in the two postbiotics with strain-specific variations, while their total short-chain fatty acid levels were comparable. Treatment with proteolytic enzymes diminished antibacterial effects only in LbP post-biotics. Both PFs tested PF showed no hemolysis of human, sheep, and rabbit red blood cell (RBC), or cytotoxicity on porcine epithelial (IPEG-J2) and normal (MRC5) cell lines, confirming their safety. These findings highlight the potential of LA and LbP postbiotics as safe and effective bioactive agents with significant antibacterial, antioxidant, and anti-inflammatory potential.

The creation of vaccines has revolutionized several aspects of the game in the fight against transmissible diseases, protecting countless individuals around the globe. Several vaccines against potentially fatal diseases such as diphtheria, pertussis, polio, measles, tetanus, influenza, and smallpox have significantly reduced disease risks and successfully immunized individuals against these serious health threats. The immune response generated by vaccination plays a crucial role in mitigating disease risks by stimulating the production of specific antibodies targeting the relevant pathogens. However, the efficacy of vaccines can vary among communities and people due to several factors, including heredity, age, sex, and preexisting health conditions. The multitude of microbes that call the human digestive tract the microbiota have a pivotal role in regulating immunological reactions to immunization, according to mounting data from both experimental models and research trials. Nutritional supplementation with beneficial microbes, such as probiotic bacteria, has been shown to have immune-related benefits, including enhancements of immune system responses, and has the potential to modify the variety that makes up the microbiota. The effectiveness of vaccines can be enhanced by using probiotics, which work by fostering a balanced gut microbiome. New research reveals that the immune response can be influenced by both live and dormant probiotic bacteria, as well as postbiotics, which are byproducts of the metabolism of probiotics. These substances have immunomodulatory functions and are essential in regulating how the immune system reacts to vaccines. This review aims to summarize the available research, explore the possible immune system functions that could explain these effects, and ultimately speculate about how postbiotics, aimed at the biotic microbiota, could improve the efficacy of vaccines. The review further addresses postbiotics’ challenges, regulatory aspects, and future directives for biotherapeutic products that could enhance vaccine efficacy and be tailored for personalized treatments.

Fasting is a diet intervention that has been shown to significantly modulate the gut microbiota, with potential health benefits. This review examines the impact of various fasting regimens, including time-restricted eating (TRE), Ramadan fasting (RF), and long-term fasting, on the composition and function of the gut microbiota in both animal models and human subjects. Studies have shown that fasting can increase microbial diversity, enrich beneficial bacteria such as Faecalibacterium prausnitzii, Roseburia spp., Akkermansia muciniphila, and other Lachnospiraceae, and enhance the production of short-chain fatty acids (SCFA) such as butyrate. These microbiota changes are associated with improvements in metabolic health markers, including body weight, blood pressure, glucose regulation, and lipid profiles, as well as reduced inflammation. However, the persistence of these effects after fasting varies between studies. Dietary changes during fasting, such as meal timing and composition, play a crucial role in shaping the response of the gut microbiota.Although most studies report beneficial results, heterogeneity in results highlights the need for more research to elucidate the relative contributions of factors such as age, baseline diet, habitual microbiota composition, fasting duration, and caloric content. The mechanistic links between specific microbial metabolites and clinical endpoints remain limited, and evidence for the synergistic effects of probiotics with fasting in humans is inconclusive. Future studies should employ standardized fasting protocols, integrate multi-omics approaches, and extend follow-up periods to determine the durability of microbiota and metabolic shifts. Developing personalized fasting strategies tailored to an individual’s baseline microbiota and metabolic phenotype may optimize the therapeutic potential of fasting for gut and metabolic health.

Gastrointestinal pathogens, including Helicobacter pylori, Salmonella spp, and Shigella spp., pose a significant global health threat due to their high incidence and prevalence rates. This research investigated the antibacterial properties of four distinct Iranian propolis ethanolic extract (PEE) samples, alongside postbiotic metabolites derived from Lacticaseibacillus rhamnosus BLRH 260 and Limosilactobacillus reuteri BLRE 269, targeting gastrointestinal pathogens. The physicochemical analysis indicated notable differences in total phenolic and flavonoid contents, as well as antioxidant activities. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were established using the microdilution method. MIC values of the mixed propolis extracts (MPEE) ranged between 7.81 and 15.62 μg/mL, while the postbiotic fractions from L.reuteri exhibited MIC and MBC values around 62.50 and 125.0 μg/mL. The antibacterial activities of the propolis extracts and postbiotic fractions varied; specifically, P4 showed the highest potency, while P1 was the least effective. Postbiotics from L. rhamnosus showed greater antibacterial activity compared to those from L. reuteri, as evidenced by agar well diffusion and MIC/MBC assessments. Importantly, the combination of propolis extracts and postbiotics produced synergistic antibacterial effects, enhancing their efficacy against all pathogens tested. Salmonella spp. displayed the highest susceptibility, whereas H. pylori was the most resistant pathogen in this study. The study suggests that propolis and postbiotic metabolites can effectively treat gastrointestinal pathogens when used in combination, recommending further research on synergy mechanisms.

Honeybees play a vital role in pollination and the maintenance of ecosystem biodiversity, making their health and well-being crucial for agriculture and environmental sustainability. Bee health is modulated by symbiotic microorganisms colonizing the gut in balanced proportions. Studies have demonstrated that these beneficial bacteria have the capacity to enhance the immune system of honey bees, having substantial impact on regulating their immunological responses and hence aiding in defending against pathogenic illnesses. Another important aspect of honeybee health is their innate immune system that is related to their ability to synthesize antimicrobial peptides (AMP). AMPs, the small, cationic peptides are the humoral effector molecules that are synthesized in the hemolymph of the insects after being exposed to microbial infectious agents. A number of honeybee's gut microbiota especially Lactic Acid Bacteria (LAB), are known to regulate the production of several AMPs and hence are able to provide protection to these insects against a number of disease agents by modulating their innate immune response via induction of the AMPs genes. These AMPs mainly produced by adult workers are an important and integral part of an insect's immune response. Several AMPs namely apidaecins, abaecins, hymenoptaecins and defensins produced in the adult honeybee, hold the ability to control or prevent a number of diseases in these pollinator insects.