**1. Introduction**

In recent years, there has been a dramatic increase of reported cases of food-borne illness because of consumption of foods contaminated with pathogenic bacteria. The presence of various microorganisms in food followed by inappropriate storage results not only in a reduction of food quality but also in spoilage of food.

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Food contaminants, such as harmful parasites, bacteria, viruses, prions, and chemical or radioactive substances, cause more than 200 diseases – ranging from infectious diseases to cancers [1]. Consequently, there is considerable interest in ways to stop this upward trend and reduce the incidence of food poisoning. The development of new and improved methods of food infectious intestinal disease preservation is of utmost importance [2]. The microbiological safety in ready-to-eat products is a cause of big concern not only for the consumers and food industries but also for the regulatory agencies. It can be said that the food industry faces a constant problem in providing the food where there are no food-borne pathogens present [3, 4]. The number of documented outbreaks of food-borne diseases has increased in the last decade, with *Salmonella* spp., *Listeria monocytogenes*, and *Escherichia coli* being responsible for the largest number of outbreaks and deaths [5].

Due to consumer awareness and negative perception of artificial preservatives in food, in recent years attention is shifting toward alternatives that the consumers recognize as natural, for example, herbal extracts. It can be said that herbal extracts have been relatively neglected as soon as modern antibiotics were discovered; they became the primary means of treating bacterial infections. Antibiotics have selective toxicity and that many important bacteria were exquisitely susceptible to them. However, bacterial infections have gone up even after the discovery of many antibiotics, mainly due to the reduced susceptibility to conventional antimicrobial agents shown by many important pathogens. Because of that, studies of the antimicrobial activity of plant extracts are intensified [6] and became prominent in science, this area has suddenly become more important in the scientific literature, and this issue is currently most attractive. Therefore, at the beginning of the 21st century, herbal extracts are getting more space in food industry to prevent the propagation of bacteria that are responsible for the spoilage of food or the spread of so-called food-borne diseases [7].

Herbal extracts, particularly essential oils (EOs) have complex composition, containing from a few dozen to several hundred constituents, especially hydrocarbons (terpenes and sesqui‐ terpenes) and oxygenated compounds (alcohols, aldehydes, ketones, acids, phenols, oxides, lactones, ethers, and esters). The greatest use of EOs in the European Union (EU) is in food (as flavorings), perfumes (as fragrances and aftershaves), and pharmaceuticals (for their func‐ tional properties). The aroma oil is the result of the combination of the main components in the oil, but trace components are also important. Thus, it is significant that the quality and composition of an EO are maintained during isolation from herb matrix, where the method of extraction plays a crucial role [8]. There are now numerous reports of the in vitro antimicrobial activity of EOs in the scientific and medical literature: EOs are found to have broad spectrum inhibitory activities against various food-borne Gram-positive and Gram-negative pathogenic bacteria.

Hydrodistillation has traditionally been applied for EO recovery from plant materials, but, during isolation, heat-sensitive compounds can easily be destroyed and quality is extremely impaired. Thus, the extraction of EO components using solvents at high pressure, or super‐ critical fluids, has received much attention in the recent years, especially in food, pharma‐ ceutical, and cosmetic industries, because it presents an alternative to conventional processes such as organic solvent extraction and steam distillation [9].

In this study, the antimicrobial properties of herbal extracts obtained by hydrodistillation and supercritical carbon dioxide (CO2) extraction from plants originated from Montenegro, sage (*Salvia officinalis*), rosemary (*Rosmarinus officinalis*), oregano (*Origanum vulgare*), and savory (*Satureja montana*), were investigated against five pathogenic bacteria important in food industry.
