Biological Properties of Plant-Derived Alkylresorcinols: Mini-Review

Abstract

Alkylresorcinols are compounds which belong to the family of phenolic lipids, and are usually found in numerous biological species. In the particular case of higher plants, alkylresorcinols have been found in various counterparts with chains of thirteen to twenty-seven carbon atoms containing several saturations. Due to the demonstrated antimicrobial properties of many naturally occurring members of the alkylresorcinols family, it is possible to conclude that these compounds act as defensive agents in plants. Previous studies led to the isolation and identification of 5-alkylresorcinols that cleave DNA. Additionally, in the literature, there are several other biological effects attributed to some resorcinol derivatives, namely, cytotoxic, anticarcinogenic, antiproliferative, antileishmanial and antioxidant properties. This mini-review intends to outline the biological activities of the most relevant alkylresorcinols isolated from plants and to propose future directions for subsequent studies regarding the effective biological effects of this class of compounds.

The substituent effect on the antioxidant capacity of catechols and resorcinols

“…The set of substituents was selected to test the impact on the alkyl groups length since it is known that alkyl resorcinols with long chains have several biological effects including antioxidants properties [15]. Furthermore, the role of unsaturated chains (alkenyl) and the presence of a C=O group in the substituent are tested on these systems.…”

“…In particular, the catechol moiety (1,2-dihydroxybenzene) is considered as an important component of natural antioxidants and for that reason, this is present in many studies [1,12,13]. Contrary to this observation, the resorcinol moiety (1,3-dihydroxybenzene) has received less attention, even though it is also present within the structure of many compounds with high antioxidant capacity, especially resorcinols substituted with alkyl groups that present different chain length and several grades of saturation [14,15]. Both structures are presented in Fig.…”

Cardanols detected in non-polar propolis extracts from Scaptotrigona aff. postica (Hymenoptera, Apidae, Meliponini)

“…Phenolic lipids can be incorporated into erythrocytes and liposomal membranes due to their hydrophilic (water-loving, polar) and lipophilic (fat-loving) properties (Stasiuk & Kozubek, 2010;Kruk et al, 2017) and can be used in pharmaceutical and fine chemical processes (Saladino et al, 2008;Behalo et al, 2016). Beside this, they also exhibited antioxidant (Andrade et al, 2011;Luís et al, 2016), antibacterial (Sibandze et al, 2016), antifeedant, cytotoxic, anticarcinogenic (Kruk et al, 2017), antiproliferative, antileishmanial, antigenotoxic (Parikka et al, 2006), antifungal (Popova et al, 2013) and anti-acetylcholinesterase activities (Oliveira et al, 2011). Cardanols are promising agents for the control of Aedes aegypti, the main dengue vector in Brazil, due to their larvicidal activity (Oliveira et al, 2011).…”

Dietary alkylresorcinols and cancer prevention: a systematic review

“…Some studies provide insight to the ARs structure-dependent relationship finding an important role of free hydroxyl, methoxyl, acetyl, or methyl groups on benzene rings for observed cytotoxicity [98,102,103]. For example, the comparable IC 50 values observed in cytotoxicity of 14 pure 5-ARs by Chuang and Wu [98] were partially explained by their antioxidant properties due to scavenging reactive oxygen species and/or inhibition of enzymes involved in the formation of free radicals under physiological conditions [70]. Alkylresorcinols contain two hydroxyl groups placed in meta-position of the phenolic ring, thus they have a week direct antioxidant potency.…”

“…Several studies reported positive correlations between whole grain intake and the presence of ARs in plasma or their urinary metabolites [36,51,[61][62][63][64][65][66][67][68][69]. Finding of in vitro studies have shown that ARs exhibit a broad range of bioactivities including a high affinity to liposome and erythrocyte membranes increasing their permeability, antifungal, antimicrobial, and anticancer abilities [70][71][72][73][74][75][76][77][78]. ARs can potentially affect all processes regulated by enzymes; this suggests that ARs may exhibit anti-oxidative, anticancer, and antimutagenic activities, induction of apoptosis, and inhibition of some enzymes activities including lipoxygenases, monoamine oxidase, tyrosinase, Ca 2+ -ATPase, α-glucosidase, dehydrogenase, DNA polymerase β, and lipase in the adipose tissue cells.…”