Bioactive compounds from Retama raetam (Forssk.) Webb & Berthel. and their insecticidal activity against cotton pests Aphis gosspyii and Amrasca biguttula.

Cotton aphids, Aphis gosspyii and cotton jassids, Amrasca biguttula are destructive piercing sucking pests to many strategic crops, especially cotton, not only in Egypt but also all over the world. Using synthetic pesticides to control these pests led to several deleterious impacts. Natural pesticides can be used as a harmless alternative. Nine compounds were isolated from different fractions of Retama raetam using chromatographic techniques and identified by spectroscopic methods as eugenol (1), alpinumisoflavone (2), licoflavone C (3), ephedroidin (4), anagyrine (5), spartiene (6), genistein-8ß-C-glucoside (7), isoprunetin (8) and isoprunetin 7-O-ß-D-glucopyranoside (9). The methanol crude extract and its fractions (hexane, chloroform, ethyl acetate and butanol), as well as the isolated compounds were examined against A. gosspyii and A. biguttula as insecticides. The results showed that chloroform fraction was the most potent fraction against A. gosspyii and A. biguttula, with LC50 values of 65.66 and 64.43 ppm, respectively. As well, compounds 1, 5 and 6 were found to be more active, with LC50 values of 69.84, 25.49 and 27.22 ppm for A. gosspyii and 65.17, 24.07 and 24.78 ppm for A. biguttula, respectively. The most potent compounds (1, 5 and 6) exhibited AChE inhibition toward A. gosspyii compared with the control. So, it can be concluded that the isolated compounds eugenol 1, anagyrine 5 and spartiene 6 are the active principles due to their capability to inhibit AchE activity.

Antibacterial Activities of Prenylated Isoflavones from Maclura tricuspidata against Fish Pathogenic Streptococcus: Their Structure-Activity Relationships and Extraction Optimization.

Streptococcus zoonotic bacteria cause serious problems in aquaculture with clinical effects on humans. A structure-antibacterial activity relationships analysis of 22 isoflavones isolated from M. tricuspidata (leaves, ripe fruits, and unripe fruits) against S. iniae revealed that prenylation of the isoflavone skeleton was an important key for their antibacterial activities (minimum inhibitory concentrations: 1.95-500 µg/mL). Through principal component analysis, characteristic prenylated isoflavones such as 6,8-diprenlygenistein (4) were identified as pivotal compounds that largely determine each part's antibacterial activities. M. tiricuspidata ripe fruits (MTF), which showed the highest antibacterial activity among the parts tested, were optimized for high antibacterial activity and low cytotoxicity on fathead minnow cells using Box-Behnken design. Optimized extraction conditions were deduced to be 50%/80 °C/7.5 h for ethanol concentration/extraction temperature/time, and OE-MTF showed contents of 6,8-diprenlygenistein (4), 2.09% with a MIC of 40 µg/mL. These results suggest that OE-MTF and its active isoflavones have promising potential as eco-friendly antibacterial agents against streptococcosis in aquaculture.

Anti-Inflammatory and Antiproliferative Prenylated Isoflavone Derivatives from the Fruits of Ficus carica.

Ficus carica is an Asian species of flowering plant belonging to the genus Ficus of the family Moraceae, native to Western Asia and the Middle East. Its fruits, usually known as common fig or fig, have been consumed as a very popular health-promoting fruit worldwide since ancient times. To investigate the potential health-promoting chemical constituents of the fruits of F. carica, a systematic phytochemical study on its fruits was therefore carried out. In our study, four new structurally diverse prenylated isoflavone derivatives, ficucaricones A-D (1-4), along with 12 known analogues (5-16) were separated from the fruits of F. carica. Their chemical structures were ambiguously elucidated based on extensive spectroscopic methods. The anti-inflammatory effects and antiproliferative activities of these isolated prenylated isoflavone derivatives were tested. Prenylated isoflavone derivatives (1-16) displayed remarkable inhibitory effects against nitric oxide (NO) production with the IC50 values ranging from 0.89 ± 0.05 to 8.49 ± 0.18 µM, comparable to that of the positive control (hydrocortisone). Furthermore, compounds 1-16 also exhibited pronounced antiproliferative activities against diverse human cancer cell lines in vitro, holding the IC50 values ranging from 0.18 ± 0.03 to 18.76 ± 0.09 µM. These findings indicate that regular consumption of the fruits of F. carica may help to prevent the occurrence of inflammatory diseases and tumors. Moreover, the isolation and characterization of these prenylated isoflavone derivatives possessing remarkable anti-inflammatory effects and antiproliferative activities could be meaningful to the discovery of new anti-inflammatory and antitumor agents.