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In the present study, norlobaridone (NBD) was isolated from Parmotrema and then evaluated as a new potent quorum sensing (QS) inhibitor against Pseudomonas aeruginosa biofilm development. This phenolic natural product was found to reduce P. aeruginosa biofilm formation (64.6% inhibition) and its related virulence factors, such as pyocyanin and rhamnolipids (% inhibition = 61.1% and 55%, respectively). In vitro assays inhibitory effects against a number of known LuxR-type receptors revealed that NBD was able to specifically block P. aeruginosa's LasR in a dose-dependent manner. Further molecular studies (e.g., sedimentation velocity and thermal shift assays) demonstrated that NBD destabilized LasR upon binding and damaged its functional quaternary structure (i.e., the functional dimeric form). The use of modelling and molecular dynamics (MD) simulations also allowed us to further understand its interaction with LasR, and how this can disrupt its dimeric form. Finally, our findings show that NBD is a powerful and specific LasR antagonist that should be widely employed as a chemical probe in QS of P. aeruginosa, providing new insights into LasR antagonism processes. The new discoveries shed light on the mysterious world of LuxR-type QS in this key opportunistic pathogen. [ABSTRACT FROM AUTHOR]

Cannabis sativa is a multipurpose plant that has been used in medicine for centuries. Recently, considerable research has focused on the bioactive compounds of this plant, particularly cannabinoids and terpenes. Among other properties, these compounds exhibit antitumor effects in several cancer types, including colorectal cancer (CRC). Cannabinoids show positive effects in the treatment of CRC by inducing apoptosis, proliferation, metastasis, inflammation, angiogenesis, oxidative stress, and autophagy. Terpenes, such as β-caryophyllene, limonene, and myrcene, have also been reported to have potential antitumor effects on CRC through the induction of apoptosis, the inhibition of cell proliferation, and angiogenesis. In addition, synergy effects between cannabinoids and terpenes are believed to be important factors in the treatment of CRC. This review focuses on the current knowledge about the potential of cannabinoids and terpenoids from C. sativa to serve as bioactive agents for the treatment of CRC while evidencing the need for further research to fully elucidate the mechanisms of action and the safety of these compounds. [ABSTRACT FROM AUTHOR]

Gingerols from the rhizome of fresh ginger (Zingiber officinale) were obtained by a simple extraction, followed by purification. The gingerols extract was composed of 6-gingerol (54%), 8-gingerol (20%), and 10-gingerol (26%). It was included into γ-cyclodextrin by classic co-dissolution procedures. Solid-state characterisation of γ-cyclodextrin·gingerols shows that this inclusion compound features 1:1 host-to-guest stoichiometry and that it is a microcrystalline powder with a crystalline cell that belongs to the tetragonal space group 4212, having the host molecules stacked in infinite channels where the gingerols are accommodated. In chimico studies with ABTS•+ scavenging, NO• scavenging, β-carotene peroxidation, and 5-LOX inhibition show that γ-cyclodextrin is a suitable carrier for gingerols, because it does not alter their reactivity towards these substances. Yogurt was tested as a matrix for the incorporation of gingerols and γ-cyclodextrin·gingerols into foodstuff. The colour of the fortified yogurt suffered little alterations. In the case of yogurt with the inclusion compound, γ-cyclodextrin·gingerols, as fortificant, these alterations were not perceptible to the naked eye. Moreover, yogurt with γ-cyclodextrin·gingerols showed a good antioxidant activity, thus being suitable for use in nutraceutical applications. [ABSTRACT FROM AUTHOR]