Intestinal microbiota interacts with other systems, especially the immune system, which is responsible for protecting the body by recognizing “stranger” (pathogen associated molecular patterns-PAMPs) and “danger” (damage-associated molecular patterns-DAMPs) molecular motifs. In this manner, it plays an important role in the pathogenesis of various diseases and health. Despite the use of probiotics that modulate the intestinal microbiota in providing health benefits and in the treatment of diseases, there are some possible concerns about the possibility of developing adverse effects, especially in people with suppressed immune systems. Since probiotics provide health benefits with bioactive compounds, studies are carried out on the use of products containing non-living probiotic microorganisms (paraprobiotics) and/or their metabolites (postbiotics) instead of probiotic products. It is even reported that these microbial compounds have more immunomodulatory activities than living microorganisms via some possible mechanism and eliminates some disadvantages of probiotics. Considering the increasing use of functional foods in health and disease, further studies are needed with respect to the benefits and advantages of parabiotic and/or postbiotic use in the food and pharmaceutical industry as well as immune system modulation. Although probiotics have been extensive studied for a long time, it seems that postbiotics are promising tools for future research and applications according to the recent literature. This review aimed to evaluate the interaction of probiotics and postbiotics with the immune systems and also their advantages and disadvantages in the area of food-pharmaceutical industry and immune system modulation.

The Brassicaceae family, known as cruciferous vegetables, includes many economically important species, mainly edible oil plants, vegetable species, spice plants, and feed plants. Cruciferous vegetables are foods rich in nutritive composition and are also a good source of dietary fiber. Besides, cruciferous vegetables contain various bioactive chemicals known as glucosinolates and S-methyl cysteine sulfoxide, including sulphur-containing cancer-protective chemicals. Numerous studies have reported that daily intake of sulphurous vegetables helps prevent cancer formation and reduces cancer incidence, especially in colorectal cancer, through various mechanisms. The potential mechanisms of these compounds in preventing cancer in experimental studies are as follows: protecting cells against DNA damage, inactivating carcinogenic substances, showing antiviral and antibacterial effects, triggering apoptosis in cells with disrupted structure, inhibiting tumour cell migration causing metastasis and the development of tumour-feeding vessels (angiogenesis). These beneficial anticancer effects of cruciferous vegetables are generally associated with glucosinolates in their composition and some secondary metabolites, as well as other phenolic compounds, seed oils, and dietary fiber in the literature. This review aims to examine to the roles of cruciferous vegetables and their important bioactive metabolites in the prevention and treatment of colorectal cancer.

Helicobacter pylori (H. pylori) is a 0.5–1 µm wide, 2–4 µm long, short helical, S-shaped Gram-negative microorganism. It is mostly found in the pyloric region of the stomach and causes chronic gastric infection. It is estimated that these bacteria infect more than half of the world’s population. The mode of transmission and infection of H. pylori is still not known exactly, but the faecal–oral and oral–oral routes via water or food consumption are thought to be a very common cause. In the last three decades, research interest has increased regarding the pathogenicity, microbial activity, genetic predisposition, and clinical treatments to understand the severity of gastric atrophy and gastric cancer caused by H. pylori. Studies have suggested a relationship between H. pylori infection and malabsorption of essential micronutrients, and noted that H. pylori infection may affect the prevalence of malnutrition in some risk groups. On the other hand, dietary factors may play a considerably important role in H. pylori infection, and it has been reported that an adequate and balanced diet, especially high fruit and vegetable consumption and low processed salty food consumption, has a protective effect against the outcomes of H. pylori infection. The present review provides an overview of all aspects of H. pylori infection, such as clinical features, treatment, and nutrition.

Omega‐3 fatty acids play a significant role in immunomodulation, with nutrigenomic approaches highlighting their impact on gene expression related to immune responses. Research indicates that omega‐3 fatty acids can modulate inflammatory pathways, potentially reducing chronic inflammation and enhancing immune function. This review discusses the intersection of nutrigenomics and nutriepigenomics, focusing on how omega‐3 fatty acids influence gene expression, immune function, and overall health. The immune system is a complex network responsible for defending the body against pathogens and maintaining internal balance. Comprised of innate and adaptive immunity, the system involves various cells, tissues, and organs working together to combat infections and prevent diseases. Omega‐3 polyunsaturated fatty acids (PUFAs), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), play a significant role in modulating the immune system. These fatty acids influence immune cell function, membrane fluidity, and signaling processes, enhancing immune responses and reducing inflammation. Furthermore, EPA and DHA affect several signaling pathways, reducing the expression of proinflammatory cytokines and inhibiting nuclear factor kappa‐light‐chain‐enhancer of activated B cells (NF‐κB) activation, a critical transcription factor in the inflammatory response. Additionally, they activate PPAR‐γ, further diminishing inflammatory gene expression. As precursors to specialized proresolving lipid mediators, EPA and DHA help shift the lipid mediator profile from proinflammatory to antiinflammatory derivatives, thus aiding in the resolution of inflammation.

Background: Olive tree (Olea europaea, Oleaceae) leaves have been widely used in traditional herbal medicine to prevent and treat various diseases especially in Mediterranean countries. They contain several potentially bioactive compounds that may have hypoglycemic and hypolipidemic properties. Summary: The literature has recently been attempting to define the relationship between olive leaf (Olea europaea L. folium) polyphenols and a number of health problems. Oleuropein, the basic phenolic compound of olive leaf and its extract, is responsible for the characteristic bitter taste and unique aroma of olive fruits. Furthermore, it is shown that oleuropein and its hydrolyzed products have many beneficial effects on human health because of its antioxidant characters. A number of studies report that olive leaf has potentially positive effects on the parameters related to diabetes and cardiovascular diseases by various mechanisms. Besides, toxicity studies suggest that olive leaf is generally safe even at high doses. Key messages: Although current results obtained until today seem promising, the studies in this subject are usually on cell culture and animal trials. Moreover, mostly the extract forms of olive leaves are used in the studies. More randomized controlled human clinical trials with extensive toxicity studies are needed to evaluate potential health effects and safety.

The need to increase food safety and improve human health has led to a worldwide increase in interest in gamma-aminobutyric acid (GABA), produced by lactic acid bacteria (LABs). GABA, produced from glutamic acid in a reaction catalyzed by glutamate decarboxylase (GAD), is a four-carbon, non-protein amino acid that is increasingly used in the food industry to improve the safety/quality of foods. In addition to the possible positive effects of GABA, called a postbiotic, on neuroprotection, improving sleep quality, alleviating depression and relieving pain, the various health benefits of GABA-enriched foods such as antidiabetic, antihypertension, and anti-inflammatory effects are also being investigated. For all these reasons, it is not surprising that efforts to identify LAB strains with a high GABA productivity and to increase GABA production from LABs through genetic engineering to increase GABA yield are accelerating. However, GABA’s contributions to food safety/quality and human health have not yet been fully discussed in the literature. Therefore, this current review highlights the synthesis and food applications of GABA produced from LABs, discusses its health benefits such as, for example, alleviating drug withdrawal syndromes and regulating obesity and overeating. Still, other potential food and drug interactions (among others) remain unanswered questions to be elucidated in the future. Hence, this review paves the way toward further studies.