Two lignans from Litsea grandis and L. gracilipes

Two lignans, grandisin and (+)-eudesmin have been isolated from Litsea grandis and L. gracilipes respectively.     

Alkene lactones from Persea fulva (Lauraceae): Evaluation of their effects on tumor cell growth in vitro and molecular docking studies

The new alkene lactone, (3E)-5,6-dihydro-5-(hydroxymethyl)-3-docdecylidenefuran-3(4H)-one (1), named majoranolide B, and three alkene lactones known as majorenolide (2), majoranolide (3) and majorynolide (4) were obtained from the aerial parts of Persea fulva (Lauraceae). The structures were elucidated in light of extensive spectroscopic analysis, including 1D, 2D NMR (¹H, ¹³C, ¹H-¹H-COSY, HMBC and HSQC) and HR-ESI-MS. These compounds were screened for their in vitro antiproliferative activity in rat C6 glioma and astrocyte cells using MTT assay and in silico by molecular docking against targets that play a central role in controlling glioma cell cycle progression. Majoranolide (3) is the most active compound with IC₅₀ 6.69 µM against C6 glioma cells, followed by the compounds 1 (IC₅₀ 9.06 µM), 2 (IC₅₀ 12.04 µM) and 4 (IC₅₀ 41.90 µM). The alkene lactones 1–3 exhibited lower toxicity in non-tumor cells when compared to glioma cells. Molecular docking results showed that majoranolide establishes hydrogen bonds with all targets through its α,β-unsaturated-γ-lactone moiety, whereas the long-chain alkyl group binds by means of several hydrophobic bonds. In the present study, it can be concluded from the anti-proliferative activity of isolates against C6 glioma cells that lactone constituents from P. fulva could have a great potential for the control of C6 glioma cells.     

PAF-antagonistic bicyclo[3.2.1]octanoid neolignans from leaves of Ocotea macrophylla Kunth. (Lauraceae)

Di-nor-benzofuran neolignan aldehydes, Δ⁷-3,4-methylenedioxy-3′-methoxy-8′,9′-dinor-4′,7-epoxy-8,3′-neolignan-7′-aldehyde (ocophyllal A) 1, Δ⁷-3,4,5,3′-tetramethoxy-8′,9′-dinor-4′,7-epoxy-8,3′-neolignan-7′-aldehyde (ocophyllal B) 2, and macrophyllin-type bicyclo[3.2.1]octanoid neolignans (7R, 8R, 3′S, 4′S, 5′R)-Δ⁸′-4′-hydroxy-5′-methoxy-3,4-methylenedioxy-2′,3′,4′,5′-tetrahydro-2′-oxo-7.3′,8.5′-neolignan (ocophyllol A) 3, (7R, 8R, 3′S, 4′S, 5′R)-Δ⁸′-4′-hydroxy-3,4,5′-trimethoxy-2′,3′,4′,5′-tetrahydro-2′-oxo-7.3′,8.5′-neolignan (ocophyllol B) 4, (7R, 8R, 3′S, 4′S, 5′R)-Δ⁸′-4′-hydroxy-3,4,5,5′-tetramethoxy-2′,3′,4′,5′-tetrahydro-2′-oxo-7.3′,8.5′-neolignan (ocophyllol C) 5, as well as 2′-epi-guianin 6 and (+)-licarin B 7, were isolated and characterized from leaves of Ocotea macrophylla (Lauraceae). The structures and configuration of these compounds were determined by extensive spectroscopic analyses. Inhibition of platelet activating factor (PAF)-induced aggregation of rabbit platelets were tested with neolignans 1–7. Although compound 6 was the most potent PAF-antagonist, compounds 3–5 showed some activity.     

金叶树属和土楠属——云南的两新记录属

报道云南热带地区两个新记录属,它们是山榄科（Sapotaceae）的金叶树属（Chrysophyllum）和樟科（Lauraceae）的土楠属（Endiandra）,并报道该地区的两个新记录种,即金叶树（Chrysophyllum lanceolatum var.stellatocarpon）和长果土楠（Endiandra dolichocarpa）。     

Effect of Neuroprotective Flavonoids of Agrimonia eupatoria on Glutamate-Induced Oxidative Injury to HT22 Hippocampal Cells

A methanolic extract of Agrimonia eupatoria (Rosaceae) significantly attenuated glutamate-induced oxidative stress in HT22 hippocampal cells. A new flavonoid, characterized as kaempferol 3-O-β-D-(2″-O-acetyl-6″-(E)-p-coumaroyl)-glucopyranoside (2″-acetyl-tiliroside (1), was isolated from the methanolic extract of A. eupatoria stems together with nine known flavonoids. Compounds 4, 7, 8 and 9 all showed a neuroprotective effect on glutamate-induced toxicity in HT22 cells.     

Evaluation of the larvicide effect of an aqueous extract of Persea americana (Miller, 1768), Lauraceae,on Anopheles gambine (Giles, 1902), Diptera Culicidae

Summary

In-laboratory evaluation of the larvicide effect of an aqueous extract of Persea americana (Miller 1768) on the various larval stages of Anopheles gambiae (Giles 1902) has shown that larvae at all stages are sensitive to this extract. Inversely proportional to the larval stage, their sensitivity proved to depend on the level of concentration: the higher the latter, the higher the former. Indeed, after a 24-h exposure, concentrations of 510 μg/ml resulted in the death of 100% of larvae at stages 1 and 2, whereas for the same time of exposure there was need to resort to concentrations of 850 μg/ml to kill them at stages 3 and 4. The aqueous extract of Persea americana has therefore a poisonous effect on larvae of Anopheles gambiae. This extract has direct lethal effects and acts as an inhibitor of larval development at sublethal concentration levels.     

Leaf alkanes in Persea and related taxa

The normal-alkane range in leaf cuticular waxes from 22 Persea species and cultivars and from the closely related genus Beilschmiedia was C₂₃ H₄₈ to C₃₅, H₇₂; alkanes with an odd number of carbon atoms predominated, C₃₃ H₆₈ usually constituting about half of the total wax. The alkane profiles gave good agreement with established taxonomy. Beilschmiedia showed an alkane distribution quite different from that of the Persea taxa. Amongst Persea species, the geographical and phylogenetic distinctiveness of P. indica and P. donnell-smithii were reflected in the distinctiveness of their alkanes. Within the subgenus Persea. the morphologically most distinct entity. P. schiedeana, also had a distinct alkane profile. Cultivars of hybrid origin indicated in their alkane proportions pronounced gene interaction.