# Brazilian Propolis: Nature's Liquid Gold with Anti-Inflammatory and Anticancer Potential
## 1 Introduction  
Propolis, also known as bee glue, is a naturally occurring viscous substance produced by honeybees. It is composed of resins, sap and mucilage comprising various parts ofplants, including tree bark, leaves and flower buds, with apian enzymatic proteins and beeswax. Propolis is utilised by honeybees to polish the inner walls of hives and repair damage and to maintain a constant humidity and temperature inside them. Additionally, the substance provides a colony with protection from pathogenic microorganisms, parasites and predators. At low temperatures, propolisis is fragile and stiff but when the temperature rises, it becomes softer, more flexible and stickier. Depending on the origin and period of storage, propolisis can have a distinct herbal smell and it comes in a variety of shades, including green, yellow, red and brown [1]. The term \"propolis\" has Greek roots. The \"pro\" prefix means defence and the parent word \"polis\" refers to a community and city or, in this context, a beehive [2]. The long history of therapeutic uses of propolisis is as old as the application of other bee products and dates back to 300 BC at least. The first people to discover the beneficial properties of propolisis were ancient Greeks, Egyptians and Romans who applied it in the treatment of wounds and as an antiseptic agent [3]. It was also used as a beauty product, a preservative and sanitiser for wounds and tumours, and for mummification. In medieval Eastern Europe and the Middle East, propolisis was widely applied as a natural medication. At the beginning of the modern era, it became the subject of research that mainly focused on identifying its chemical composition [4]. In Brazil, fourteen types of propolisis have been documented and categorised according to their geographic location, physicochemical features and botanical origin [5]. In tropical and subtropical regions, due to differences in vegetation, propolisis has a distinct appearance, chemical composition and properties that distinguish it from poplar propolisis. The main botanical sources of Brazilian propolisis are _Baccharis dracunculifolia_ [PERSON], _Dalbergia castophylum_ ([PERSON]) [PERSON], _Araucaria angustifolia_ ([PERSON].) [PERSON], and _Eucalyptus citridora_ ([PERSON].) [PERSON] & [PERSON]. [6]. The green, red and brown varieties are the most studied types of Brazilian propolisis. They are also important for the Brazilian economy due to their health-promoting properties and exports to other countries, like Japan [7]. Brazilian propolisis exhibits a variety of biological properties, producing anticancer, anti-inflammatory, antioxidant, antimicrobial and antiparasitic effects [8; 9; 10; 11]. The anti-inflammatory and anticancer properties represent some of the most well-documented activities of Brazilian propolisis, simultaneously addressing two major global health challenges. Current statistics highlight the increasing incidence of cancer worldwide in both men and women, which emphasizes the need for greater efforts aimed at prevention, early detection and effective treatment of the disease. The World Health Organization (WHO) estimates that the number of cancer cases may reach 35.3 million by 2050 [12]. One of the factors closely associated with cancer development is chronic inflammation, which increases the risk or progression of cancer and involves genetic instability [13]. Having considered the close relationship between persistent inflammation and cancer development, the identification and activity of compounds that exert both effects is of high importance. Brazilian propolisis presents a very rich chemical profile. Compounds found in its composition include, among others, polyisoprenylated benzophenones, xanthones, triterpenoids, chalcones, flavonols [14], flavonoid glycosides, preynylated flavonoids [15], phenolic acids and artepilin C, which only confirm its biological properties [5]. The efficacy of Brazilian propolisis depends on its solubility in various solvents varying in polarity.