The world around us is composed of a variety of organic compounds that form the animal and plant species. One of the larger groups amongst them are terpenoid compounds, either the structurally simplest monoterpenoids, or sesquiterpenoids containing several atoms or even di- and triterpenoids composed of several carbon atoms. Many of these compounds contain lactone moiety in their structure [1–27]. Equally often, a component of their structure is a hydroxyl group [1–23]. Sometimes, the structural element can also be a halogen atom [24–27]. Many of the hydroxylactones exhibit interesting biological properties, such as antimicrobial (Fig. 1, 2, 12, 13), [2, 3, 19, 21], cytotoxic (Fig. 4, 6, 8), [8, 12, 14], anti-inflammatory (Fig. 1, 4, 11, 14), [3, 9, 18, 22], anti-fungal (112 Fig. 13), [19, 21] or liver protection (Fig. 4, 9) [8, 15]. Some of these compounds also exist as flavoring or taste agents in food (Fig. 3, 10), [7, 16], inhibitors of overproduction nitrogen sulfide (5, 6, 11), [10, 12, 18] or pesticides (Fig. 2, 13), [6, 20]. Hydroxylactones are usually isolated from plants, in many cases, those that are used in traditional folk medicine (Fig. 1, 4, 6, 7, 9, 11, 14, 15, 17), [1, 3, 8, 9, 12, 13, 15, 18, 22, 23, 25, 26], and sometimes from the other organisms, such as microorganisms or fungi (Fig. 2, 5), [6, 10]. Lactones that contain a chlorine atom in their structure, in addition to or instead of the hydroxy group usually have cytotoxic properties (16, 17), [15, 25, 27]. They are found in both land- -based plants, mainly belonging to the family Asteraceae (Fig. 17) [25–27] as well as in marine organisms (Fig. 16), [24], in which the presence of chlorine atoms can be a result of the presence of salt (chloride) in seawater. The following article presents an overview of the various sources from which hydroxylactones and chlorolactones were isolated and also biological properties of these compounds.
