Clausena lansium Lour. Skeels (Rutaceae) is widely distributed in South China and has historically been used as a traditional medicine in local healthcare systems. Although the characteristic components (carbazole alkaloids and coumarins) of C. lansium have been found to possess a wide variety of biological activities, little attention has been paid toward the other components of this plant. In the current study, phytochemical analysis of isolates from a water-soluble stem and leaf extract of C. lansium led to the identification of 12 compounds, including five aromatic glycosides, four sesquiterpene glycosides, two dihydrofuranocoumarin glycosides, and one adenosine. All compounds were isolated for the first time from the genus Clausena, including a new aromatic glycoside (1), a new dihydrofuranocoumarin glycoside (6), and two new sesquiterpene glycosides (8 and 9). The phytochemical structures of the isolates were elucidated using spectroscopic analyses including NMR and MS. The existence of these compounds demonstrates the taxonomic significance of C. lansium in the genus Clausena and suggests that some glycosides from this plant probably play a role in the anticancer activity of C. lansium to some extent.

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1,3-dichloropropene (1,3-D) was evaluated as a potential alternative for the widely used soil fumigant methyl bromide (MeBr) in cucumber (Cucumis sativus Linn.) crops in China. Six treatments were replicated five times in a randomized complete block design: fumigation with MeBr (400 kg·ha(-1)), three 1,3-D doses (90, 120, and 180 L·ha(-1)), an avermectin dose (7.5 L·ha(-1)), and a nontreated control. Results consistently indicated that MeBr was generally superior to the treatments involving all 1,3-D and avermectin, which in turn were superior to the control, for improving cucumber yield and to control nematode and weed. In two successive seasons, 1,3-D at a dose of 180 L·ha(-1) was as effective as MeBr in increasing plant height, vigor, and yield, as well as showed excellent nematode control efficiency, but it had relatively poor potency to control weeds. The present data support the conclusion that 1,3-D is a promising MeBr alternative for managing nematodes and weeds in cucumber crops and can be used in integrated pest management programs.

BACKGROUND Clausena lansium (Lour.) Skeels, belonging to the genus Clausena of the family Rutaceae, has a wide range of medical and agricultural activities. Previous studies on agricultural activities have shown that C. lansium extracts and some components have obvious herbicidal activities. In order to study systematically herbicidal activity of this plant, we studied the herbicidal effect of ethyl acetate (EtOAc) extract from the stems and leaves of this plant and further isolated the active compounds. RESULTS The EtOAc extract inhibited the growth of roots and shoots of Echinochloa crus‐galli (L.) Beauv., and the inhibitory effect of the EtOAc extract on roots were stronger than those on shoots with half maximal inhibitory concentration (IC50) values of 420.45 and 585.05 mg L−1, respectively. Fifteen compounds were subsequently isolated and identified from the stems and leaves of C. lansium, including nine O‐monoterpenoid furanocoumarins and six cinnamamides. Our results showed that most compounds exhibited varying degrees of herbicidal activities to E. crus‐galli. Among them, compounds 3, 8, and 13–15 showed the best inhibitory activities on the growth of E. crus‐galli roots, with inhibition rate values ranging from 70% to 83% at a concentration of 300 mg L−1. Compounds 1 and 2 are two new compounds, and their structures were established as 5‐O‐monoterpenoid furanocoumarin and 8‐O‐monoterpenoid furanocoumarin, and named as claulansicoumarin‐A and ‐B, respectively. CONCLUSION The EtOAc extract and pure compounds showed noticeable herbicidal activities against E. crus‐galli and indicated a great potential for these natural compounds to be developed as a herbicide. © 2020 Society of Chemical Industry

The effects of esterified lactoferrin (ELF) and lactoferrin (LF) on blue mold caused by Penicillium expansum in apple fruit stored at 25 °C were investigated. Both ELF and LF provided an effective control and strongly inhibited spore germination and germ tube elongation of P. expansum in vitro. Assessment by propidium iodide staining combined with fluorescent microscopy revealed that the plasma membrane of P. expansum spores was damaged more seriously by ELF than by LF treatment, and the leakage of protein and sugar was higher from ELF-treated mycelia. Interestingly, ELF treatment induced a significant increase in the activities of chitinase, β-1,3-glucanase, and peroxidase in apple fruit, whereas both LF treatment and the control showed no obvious difference. These findings indicated that the effects of ELF on blue mold in apple fruit might be associated with the direct fungitoxic property against the pathogens and the elicitation of defense-related enzymes in fruit.