Lignans from Medicinal Plants and their Anticancer Effect.

Since early times, various plants have been used as remedies for treating different kinds of diseases and lesions with satisfying results. The phenolic compounds are secondary metabolites from medicinal plants which include a wide category of compounds such as phenolic acids, flavonoids, tannins, stilbenes, curcuminoids, xanthones, coumarins, lignans, etc. Between these, lignans are considered important in cancer prevention and treatment, besides other beneficial health effects, e.g. antioxidant, anticarcinogenic, antimutagenic, and anti-estrogenic effects. This review summarizes the most recent literature and the most important results concerning plant lignans and their derivatives in cancer prevention and treatment, both in vitro and in vivo assessments. The mechanistic aspects will be also highlighted.

Chemical and Bioactivity Evaluation of Eryngium planum and Cnicus benedictus Polyphenolic-Rich Extracts.

This study evaluated the biological activities of Eryngium planum and of Cnicus benedictus extracts enriched in polyphenols obtained by nanofiltration. The HPLC-MS analysis showed that E. planum contains mainly flavonoids, especially rutin, while in C. benedictus extracts show the high concentration of the phenolic acids, principally the chlorogenic acid and sinapic acid. Herein, there is the first report of ursolic acid, genistin, and isorhamnetin in E. planum and C. benedictus. C. benedictus polyphenolic-rich extract showed high scavenging activity (IC50=0.0081 mg/mL) comparable to that of standard compound (ascorbic acid) and a higher reducing power (IC50= 0.082 mg/mL), with IC50 having a significantly lower value than IC50 for ascorbic acid. Both extracts were nontoxic to NCTC cell line. Among the investigated herbs, E. planum polyphenolic-rich extract showed the highest inhibitory activities with the IC50 value of 31.3 µg/mL for lipoxygenase and 24.6 µg/mL for hyaluronidase. Both polyphenolic-rich extracts had a higher inhibitory effect on α-amylase and α-glucosidase than that of the acarbose. The synergistic effect of ursolic acid, rutin, chlorogenic acid, rosmarinic acid, genistin, and daidzein identified in polyphenolic-rich extracts could be mainly responsible for the pharmacological potentials of the studied extracts used in managing inflammation and diabetes.