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The CH 2 Cl 2 -MeOH (1:1) extract of roots of Rumex nepalensis (Polygonaceae) displayed significant antibacterial activity against five bacterial strains with MICs (62.5-31.2 μg.mL -1 ). The EtOAc soluble fraction displayed a significant activity against the same strains with MICs (31.2-3.9 μg.mL -1 ). The purification of the EtOAc fraction yielded one new phenylisobenzofuranone derivative, berquaertiide ( 1 ), along with 19 known compounds ( 2 - 20 ). Their structures were elucidated based on the analysis of their NMR and MS data. All the isolated compounds were assessed for their antibacterial activity. Compound 2 was the most active against all the tested strains (15.7 to 1.9 μg.mL -1 ), while compounds 3 - 7 displayed good activities on at least one of the tested strains. In addition, seven analogues ( 21 - 27 ) of compound 2 were prepared and further assessed for their antibacterial activity. Compounds 26 and 27 were most active than 2 against Salmonella enterica and Klebsiella pneumoniae with MIC (125 and 15.6 μg.mL -1 , respectively).

Crotofoligandrin ( 1 ), a new endoperoxide crotofolane-type diterpenoid was isolated from the dichloromethane/methanol (1:1) extract of the twigs of Croton oligandrus Pierre Ex Hutch along with thirteen known secondary metabolites including 1-nonacosanol ( 2 ), lupenone ( 3 ), friedelin ( 4 ), β -sitosterol ( 5 ), taraxerol ( 6 ), (-)-hardwickiic acid ( 7 ), apigenin ( 8 ), acetyl aleuritolic acid ( 9 ), betulinic acid ( 10 ), fokihodgin C 3-acetate ( 11 ), D-mannitol ( 12 ), scopoletin ( 13 ) and quercetin ( 14 ). The structures of the isolated compounds were determined based on their spectroscopic data. The crude extract and the isolated compounds were assessed in vitro for their antioxidant, lipoxygenase, butyrylcholinesterase (BChE), urease and glucosidase inhibitory potentials. Compounds 1 - 3, and 10 displayed activities on all the performed bioassays. All the tested samples showed strong to significant antioxidant activity with compound 1 being the most potent (IC 50 39.4 μM)., (© 2023 Walter de Gruyter GmbH, Berlin/Boston.)

Ripe figs, barks, and wood of Ficus vallis-choudae are used in traditional medicine against several conditions including nausea and malaria. However, its use is still to be scientifically documented and validated. Hence, the aim of the present work was to evaluate the antiplasmodial activity of the dichloromethane-methanol (DCM-MeOH (1:1)) crude extract, their hexane, dichloromethane, ethyl acetate, and methanoli fractions, as well as the isolated chemical constituents. The chemical study of the DCM-MeOH (1:1) crude extract of F. vallis-choudae figs led to the isolation of fifteen (15) known compounds identified based on their spectroscopic data [one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR), mass spectrometry] and by comparison of these data with those reported in the literature. Some of the isolated compounds were assessed in vitro for their antiplasmodial activity against Plasmodium falciparum chloroquine-sensitive 3D7 (Pf3D7) and multidrug-resistant Dd2 strains. The dichloromethane fraction exhibited very good antiplasmodial activity against both strains with IC 50 values of 13.86 μg/mL and 8.18 μg/mL, respectively. Among the tested compounds, wighteone (2) was the most active against P. falciparum 3D7 (IC 50  = 24.6 ± 1.5 μM) and Dd2 (IC 50  = 11.9 ± 2.4 μM) strains. The obtained results could justify the traditional uses of F. vallis-choudae against malaria. Wighteone appears to be the most active ingredient. However, further consideration of this compound as starting point for antimalarial drug discovery will depend upon its selectivity of action towards Plasmodium parasites. HIGHLIGHTS: • 15 (fifteen) compounds were isolated from the dichloromethane-methanol extract of Ficus vallis-choudae. • Their structures were determined on the basis of their spectroscopic data. • The dichloromethane fraction showed promising activities on the Pf3D7 and PfDd2 strains with IC 50 values of 13.86 and 8.18 µg/mL, respectively. • Wighteone was the most active compound against PfDd2 (IC 50  = 11.9 ± 2.4 μM)., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The MeOH/CH 2 Cl 2 (1:1) extracts of the roots and leaves of Beilschmiedia louisii and B. obscura showed potent antitrypanosomal activity during preliminary screening on Trypanosoma brucei brucei . Phytochemical investigation of these extracts led to the isolation of a mixture of two new endiandric acid derivatives beilschmiedol B ( 1 ) and beilschmiedol C ( 2 ), and one new phenylalkene obscurene A ( 3 ) together with twelve known compounds ( 4 - 15 ). In addition, four new derivatives ( 11a - 11d ) were synthesized from compound 11 . Their structures were elucidated based on their NMR and MS data. Compounds 5 , 6 , and 7 were isolated for the first time from the Beilschmiedia genus. Additionally, the NMR data of compound 4 are given here for the first time. The isolates were evaluated for their antitrypanosomal and antimalarial activities against Tb brucei and the Plasmodium falciparum chloroquine-resistant strain Pf3D7 in vitro, respectively. From the tested compounds, the mixture of new compounds 1 and 2 exhibited the most potent antitrypanosomal activity in vitro with IC 50 value of 4.91 μM.

There is continuing need for new and improved drugs to tackle malaria, which remains a major public health problem, especially in tropical and subtropical regions of the world. Natural products represent credible sources of new antiplasmodial agents for antimalarial drug development. Endophytes that widely colonize healthy tissues of plants have been shown to synthesize a great variety of secondary metabolites that might possess antiplasmodial benefits. The present study was carried out to evaluate the antiplasmodial potential of extracts from endophytic fungi isolated from Symphonia globulifera against a chloroquine-resistant strain of Plasmodium falciparum (PfINDO ). Sixty-one fungal isolates with infection frequency of 67.77% were obtained from the bark of S. globulifera . Twelve selected isolates were classified into six different genera including Fusarium , Paecilomyces , Penicillium , Aspergillus , Mucor, and Bipolaris . Extracts from the 12 isolates were tested against PfINDO , and nine showed good activity (IC 50 < 10 &mu;g&middot;mL &minus;1 ) with three fungi including Paecilomyces lilacinus (IC 50 = 0.44 &mu;g&middot;mL &minus;1 ), Penicillium janthinellum (IC 50 = 0.2 &mu;g&middot;mL &minus;1 ), and Paecilomyces sp. (IC 50 = 0.55 &mu;g&middot;mL &minus;1 ) showing the highest promise. These three isolates were found to be less cytotoxic against the HEK293T cell line with selectivity indices ranging from 24.52 to 70.56. Results from this study indicate that endophytic fungi from Symphonia globulifera are promising sources of hit compounds that might be further investigated as novel drugs against malaria. The chemical investigation of active extracts is ongoing.