Occurrence and Biological Activities of Seco-Iridoids from Jasminum L.

In this paper, the first complete review on the seco-iridoids from the genus Jasminum L. was presented. In particular, their occurrence in the genus was detailed together with their biological activities. The literature survey has clearly pointed out that only a few Jasminum species have been studied for their seco-iridoid content evidencing oleoside derivatives as main compounds. In addition, the biological studies performed on them are very scarce focusing mainly on antioxidant and anti-inflammatory assays with modest effectiveness. All these results greatly underline the need for further in-depth analyses on these compounds under both the aspects.

Evaluation of the Antifungal and Antiproliferative Properties of the Lichen Roccella tinctoria DC. Extracts and Main Components.

In this work, phytochemical analysis on different extracts of Roccella tinctoria DC. was reported using different techniques with respect to the past. Twenty volatile and three non-volatile compounds were identified, some of which were found in this species for the first time. The methanolic extracts and their non-volatile components were then evaluated for their antitumor effects in cancerous A549 and Mz-ChA-1 cells and for their tolerability in non-cancerous BEAS-2B and H69 cells, showing IC50 values from 94.6 µg/mL to 416.4 µg/mL, in general. The same extracts and compounds were also tested for their antifungal effects in Candida albicans, with only compound 2 being active, with an MIC50 value of 87 µg/mL. In addition, they were tested for their anti-Candida adhesion activity, anti-Candida biofilm formation, and anti-Candida mature biofilm inhibition, with efficacy percentages generally above 50% but not for all of them. Lastly, the DF3 extract and compounds 1-2 were tested in vivo according to the Galleria mellonella survival assay, showing positive mortality rates above 50% at different concentrations. All these biological assays were conducted on this species for the first time. Comparisons with other lichens and compounds were also presented and discussed.

Protective Effect of Procyanidin-Rich Grape Seed Extract against Gram-Negative Virulence Factors.

Biofilm formation and lipopolysaccharide (LPS) are implicated in the pathogenesis of gastrointestinal (GI) diseases caused by Gram-negative bacteria. Grape seeds, wine industry by-products, have antioxidant and antimicrobial activity. In the present study, the protective effect of procyanidin-rich grape seed extract (prGSE), from unfermented pomace of Vitis vinifera L. cv Bellone, on bacterial LPS-induced oxidative stress and epithelial barrier integrity damage has been studied in a model of Caco-2 cells. The prGSE was characterized at the molecular level using HPLC and NMR. The in vitro activity of prGSE against formation of biofilm of Salmonella enterica subsp. enterica serovar Typhimurium and Escherichia coli was investigated. In vivo, prGSE activity using infected Galleria mellonella larvae has been evaluated. The results show that the prGSE, if administered with LPS, can significantly reduce the LPS-induced permeability alteration. Moreover, the ability of the extract to prevent Reactive Oxygen Species (ROS) production induced by the LPS treatment of Caco-2 cells was demonstrated. prGSE inhibited the biofilm formation of E. coli and S. Typhimurium. In terms of in vivo activity, an increase in survival of infected G. mellonella larvae after treatment with prGSE was demonstrated. In conclusion, grape seed extracts could be used to reduce GI damage caused by bacterial endotoxin and biofilms of Gram-negative bacteria.

Protective Role of Natural Compounds under Radiation-Induced Injury.

In recent years, evidence has shown the potential therapeutic effects of different natural compounds for the prevention and treatment of radiotherapy-induced mucositis (RIOM). RIOM represents one of the most frequent side effects associated with anti-neoplastic treatments affecting patients' quality of life and treatment response due to radiation therapy discontinuation. The innate radio-protective ability of natural products obtained from plants is in part due to the numerous antioxidants possessed as a part of their normal secondary metabolic processes. However, oxygen presence is a key point for radiation efficacy on cancer cells. The aim of this review is to describe the most recent evidence on radiation-induced injury and the emerging protective role of natural compounds in preventing and treating this specific damage without compromising treatment efficacy.