Steroidal saponins are widely distributed among monocots, including the Amaryllidaceae family to which the Allium genus is currently classified. Apart from sulfur compounds, these are important biologically active molecules that are considered to be responsible for the observed activity of Allium species, including antifungal, cytotoxic, enzyme-inhibitory, and other. In this paper, literature data concerning chemistry and biological activity of steroidal saponins from the Allium genus has been reviewed.

Quercetin is one of the most common, naturally occurring flavonoids, structurally classified to the flavonol subfamily. This compound, found in many edible and medicinal plants either as a free or glycosidated form, has been scientifically exploited for many years, and one could hardly expect it could be a hero of some additional story. Commonly recognized as an anti-inflammatory agent, quercetin not only limits capillary vessel permeability by inhibiting hyaluronidase but also blocks cyclooxygenases and lipoxygenases. As a typical flavonoid, it is also known for its antioxidant effect, which was confirmed by many in vitro and in vivo studies. Throughout the years, numerous other activities were reported for quercetin, including antidiabetic, anti-proliferative, or anti-viral. Of note, recent data have revealed its potential role as a therapeutic agent for several central nervous system disorders. This review provides an overview of available experimental data on quercetin and its complexes with respect to central nervous system diseases, with a main focus on some aspects that were not discussed previously, such as anti-anxiolytic effects, anti-Huntington’s disease activity, or therapeutic potential in brain cancer. Moreover, quercetin’s protective role in some of these diseases is discussed, especially as an anti-neuroinflammatory agent. Bearing in mind the poor bioavailability of this compound, possible options that would enhance its delivery to the site of action are also presented.

The objective of this study was to evaluate the usefulness of a hydroalcoholic extract from Galinsoga parviflora herb (GP) in some aspects of the endothelial cell function necessary for anti-inflammatory activity and wound healing and relate these to the GP phytochemical profile. This study demonstrated that the GP extract caused a dose-dependent reduction of IL-6 secretion on IL-1β-stimulated endothelial cells. The IL-6 release was decreased to 33% ± 9% while this did not influence the IL-6 secretion without stimulation. Additionally, the GP extract exhibited an anti-hyaluronidase activity (IC₅₀ = 0.47 mg/mL), which was evidently stronger than the positive control kaempferol (IC₅₀ = 0.78 mg/mL) as well as a moderate and concentration-dependent, antioxidant activity. The results of the scratch assay showed that exposure of the endothelial cells to GP induced complete healing of the damage after 12 h of the study. The phytochemical profile of the extract was studied by using spectrophotometric (total amount of polyphenols and flavonoids) and UPLC (phenolic acids) methods. The main compound in the GP extract was a chlorogenic acid (2.00 ± 0.01 mg/g by UPLC). The total content of polyphenols was 98.30 ± 0.14 mg of chlorogenic acid equivalent/g of the dry herb and content of flavonoids amounted to 6.15 ± 0.41 mg quercetin equivalent/g of the dry herb. Moreover, the presence of flavonoids in G. parviflora was provided after their isolation and identification by spectroscopic methods. In conclusion, it demonstrated that application of GP in the treatment of skin lesions gives possibility of wound healing based on antioxidant, anti-inflammatory, and hyaluronidase-inhibiting activities of G. parviflora herb extract.

Steroidal saponins are a group of glycosides widely distributed among monocotyledonous families. They exert a wide spectrum of biological effects including cytotoxic and antitumor properties which are the most studied. This review is an update of our previous paper—Saponins as cytotoxic agents(Podolak et al. in Phytochem Rev 9:425–474, 2010) and covers studies that were since published (2010–2018). In this paper we refer to steroidal saponins presenting results of cytotoxicity studies, mechanisms of action and structure–activity relationships.

The in vitro anti-denaturation and anti-hyaluronidase activities of Impatiens parviflora extracts and isolated galactolipids (MGDG-1, DGDG-1) were investigated. This is the first report on these compounds in I. parviflora. All extracts showed anti-hyaluronidase activity, but only methanolic extract from fresh leaves exhibited significant activity against heat-induced denaturation of BSA in a dose-dependent manner. At 500 μg/mL, the extract and the reference drug showed 79.05% and 99.81% inhibition of protein denaturation, respectively. These results indicate that fresh leaves of I. parviflora may be beneficial in inflammatory conditions, especially those associated with protein denaturation, such as rheumatoid arthritis. The study revealed that only MGDG-1 showed weak activity in anti-denaturation assay but both galactolipids were potent inhibitors of hyaluronidase. MGDG-1 completely inhibited the enzyme activity at the concentration of 127.9 μg/mL. These results indicate the potential of galactolipids in the treatment of diseases associated with the loss of hyaluronic acid.