Studies on fermentation by acid lactic bacteria (LAB) have confirmed the presence of strains with attributes of considerable relevance for food processing. These strains, in addition to their ability to modify the texture and flavor of foods, possess beneficial properties for human health. They enhance food quality by making it more nutrient-rich and contribute to food preservation. The production of lactic acid, vitamins, exopolysaccharides, and bacteriocins, among other compounds, confers these properties to LAB. In the realm of preservation, bacteriocins play a crucial role. This is because bacteriocins act by inhibiting the growth and reproduction of unwanted microorganisms by interacting with the cell membrane, causing its rupture. This preservative effect has led LAB to have widespread use during food processing. This preservative effect has led to widespread use of LAB during food processing. This review highlights the importance of fermentation carried out by LAB in the food industry and in the bio-preservation of foods. These findings emphasize the relevance of continuing investigations and harness the properties of LAB in food production.

Flourensia cernua DC, commonly known as hojasen or tarbush, is a medicinal plant used in arid regions due to its therapeutic properties, especially in the treatment of gastrointestinal disorders. This study aimed to assess the toxicity of a polyphenolic extract obtained from F. cernua. This research involved both in vitro (hemolytic and brine shrimp assay) and in vivo tests (acute oral toxicity) to determine the safety profile of this extract. The extract was obtained through a novel ultrasound‐microwave extraction and purified by ion‐exchange chromatography. Analysis of the polyphenolic extract revealed a rich composition of flavonoids and hydroxycinnamic acids, mainly apigenin glycosides. In toxicity tests, the polyphenols did not exhibit toxicity towards Artemia salina at a concentration of 1 mg/ml. Furthermore, incubation at 500 μg/ml for 4 hours showed a slight toxic effect on erythrocytes. In the acute oral toxicity test in mice, doses of 300 mg/kg and 2000 mg/kg did not result in animal mortality, indicating that the LD₅₀ exceeds 2000 mg/kg. However, the higher dose induced signs of toxicity, including lethargy, drowsiness, piloerection, and a significant decrease in weight during the initial two days postadministration of the polyphenolic extract. In addition, histological analysis suggested potential kidney damage at the 2000 mg/kg dose. According to OECD guidelines, while the extract can be classified as category 5 (low acute toxicity) due to the absence of mortality at 2000 mg/kg, the observed signs of toxicity should be considered in the overall risk assessment. These findings highlight the potential of F. cernua in pharmaceutical and nutraceutical applications due to its high polyphenolic content. However, further investigations are necessary to explore the specific effects of the compounds present in the extract. In addition, continuous evaluation of its long‐term toxicity is essential to fully understand the extract’s safety profile and efficacy.

Lactic acid bacteria (LAB) have historically been used in fermentation processes, playing a key role in the development of foods with health benefits. Understanding the factors that affect LAB functionality is essential for optimizing their application. During fermentation processes, LAB produce different metabolites of interest, such as lactic acid, gamma-aminobutyric acid (GABA), and short-chain fatty acids, whose production is influenced by conditions such as temperature and pH. Although LAB exhibit optimal growth ranges, their ability to adapt to moderate variations makes them particularly valuable in various applications. Currently, the impact of these LAB metabolites on human physiology is being actively investigated, especially for modulation of the Microbiota–Gut–Brain axis. Certain compounds derived from LAB have been shown to contribute to neurological, immunological, and metabolic processes, opening new perspectives for the design of functional foods. This article provides a comprehensive overview of the importance of lactic acid bacteria in human health and highlights their potential for the development of innovative strategies to promote well-being through diet.