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Chemical investigation of the Penicillium sp. SCSIO 41038 led to the isolation and characterization of one new cyclopiazonic acid-type alkaloid, speradine I ( 1 ), and one new phloroglucinol derivative, speradine J ( 8 ), along with 13 known compounds. Their structures were determined on the basis of extensive spectroscopic analysis, and by a comparison with data from the literature. All the compounds were evaluated for their antitumor (22Rv1 and PC-3) and enzyme inhibitory activity against acetylcholinesterase (AChE) in vitro .

The genus Knema Lour. is distributed mainly in Southeast Asian and widely used in folk medicine for treating diseases such as jaundice, chronic fever, and inflammation. The chemical composition, acetylcholinesterase inhibition, and molecular docking studies of essential oil from Knema hookeriana Warb. were investigated in this study. The essential oil was achieved through hydrodistillation and was characterised using gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The acetylcholinesterase inhibitory activity was evaluated using Ellman method while molecular docking studies were carried out using Autodock v.4.3.2. The results revealed that the essential oil examined consisted mainly of β-caryophyllene (26.2%), germacrene D (12.5%), δ-cadinene (9.2%), germacrene B (8.8%) and bicyclogermacrene (5.5%). The essential oil showed acetylcholinesterase activity with IC 50 value of 70.5 µg/mL. The enzyme-ligand molecular docking study showed that β-caryophyllene and δ-cadinene exhibited good binding affinities towards AChE with docking scores -8.1 kcal/mol and -8.3 kcal/mol, respectively.

GC/MS analysis of Murraya koenigii (L.) Spreng. and Murraya paniculata (L.) Jacq. leaves revealed the identification of 73 components, with an evident greater contribution of monoterpenes hydrocarbons to their total volatiles. α-Pinene (37.5%) and β-caryophyllene (27.4%) were the most abundant compounds in M. koenigii leaves and β-phellandrene (40.7%) in M. paniculata leaves, using headspace. β-Phellandrene (33.7%) was the major constituent by M. koenigii leaves where germacrene D (23.8%), and δ-elemene (22.0%) were predominant in M. paniculata leaves, using steam distillation. M. koenigii leaves oil showed quite remarkable cholinesterase inhibitory activity, where oil of M. paniculata leaves showed strong inhibitory activity against AChE (IC 50 =13.2 ± 0.9 µg/mL) and BChE (IC 50 =5.1 ± 0.3 µg/mL). Germacrene D, α-zingiberene, and δ-elemene showed higher affinity to BChE than AChE as revealed from docking scores (S = -5.65 to -6.03 Kcal/mol) for BChE and (S = -5.56 to -6.25 Kcal/mol) for AChE.

The present study provides the first information on the chemical composition and acetylcholinesterase inhibitory activity of the essential oil (EO) from the leaves of Mitrephora poilanei Weeras. & R.M.K.Saunders from Vietnam. Gas chromatography and gas chromatography-mass spectrometry analysis revealed that the main components of the M. poilanei EO were β-caryophyllene (13.2%), α-humulene (10.5%), germacrene D (8.1%), β-elemene (5.2%) and bicyclogermacrene (5.1%). The anti-acetylcholinesterase assay showed that the EO displayed moderate activity with IC 50 value of 31.16 ± 3.06 μg/mL. These findings proposed that the plant can be exploited for its anti-acetylcholinestrate potential.

Methanolic stem bark extracts from ten Mexican Bursera Jacq. ex L. species were evaluated in vitro with regard to their inhibitory activity against two Tenebrio molitor -derived enzymes. Seven extracts ( B. bicolor , B. copallifera , B. fagaroides , B. grandifolia , B. lancifolia , B. linanoe , and B. longipes ) reduced α-amylase activity by 55.37% to 96.25%, with three samples proving to be particularly potent α-amylase inhibitors ( B. grandifolia , B. lancifolia , and B. linanoe ; IC 50 = 162, 132, and 186 µg/mL, respectively). In contrast, no extract inhibited acetylcholinesterase activity by more than 39.94%. Quantitative HPLC analysis did not reveal any clear correlation between the species-specific flavonoid or phenolic acid profiles and the respective extracts' enzyme inhibitory activity. The findings reported herein do not only contribute to improving the current state of knowledge regarding the enzyme inhibitory potential of the Bursera genus, but could also lead to the development of new sustainable bioinsecticides.

Pulicaria undulata is used as a traditional herbal remedy in Egypt. We used gas chromatography-mass spectrometry for analysis of essential oil of this plant growing wild in Egypt and 64 compounds were identified. The oil was rich in oxygenated monoterpenes (64.0%) and aromatic derivatives (18.8%). The major components were carvacrol (46.5%), xanthoxylin (18.1%) and carvotanacetone (8.7%). The oil of the Egyptian plant showed significant differences from the oil results reported on this species derived from different accessions. Antioxidant activity was performed by FRAP, DPPH and ABTS assays, and the oil demonstrated a powerful antioxidant properties. Furthermore, cytotoxicity was assessed using MTT assay against three cell lines (A375, T98G, HCT116) and the oil showed moderate results with IC 50 of 18.53, 40.64 and 22.23 μg/ml; respectively. The oil showed a good anti-acetylcholinesterase activity (IC 50  = 139.2 μg/ml) using Ellman method. In conclusion, the studied oil exhibited a peculiar fingerprint and promising biological activities.

Two new alkaloids, fluevirines E ( 1 ) and F ( 2 ), along with six known Securinega alkaloids, were isolated from the methanol extract of the twigs and leaves of Flueggea virosa . The structures and absolute configurations of the new compounds were elucidated by means of MS, NMR, and ECD analyses. Compound 1 is a new dimeric indole alkaloid while 2 is a new securinega-type alkaloid. The in vitro cytotoxic activities of the isolated alkaloids against several human cancer cell lines and their acetylcholinesterase inhibitory activity were also evaluated.

α -mangostin, a polyphenol xanthone derivative, was mainly isolated from pericarps of the mangosteen fruit ( Garcinia mangostana L.). In present investigation, a series of derivatives were designed, synthesised and evaluated in vitro for their inhibitory activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Among the synthesised xanthones, compounds 1 , 9 , 13 and 16 showed AChE selective inhibitory activity, 15 was a BuChE selective inhibitor while 2 , 3 , 5 , 6 , 7 , 12 and 14 were dual inhibitors. The most potent inhibitor of AChE was 16 while 5 was the most potent inhibitor of BuChE with IC 50 values of 5.26  μ M and 7.55  μ M respectively.

Five phenanthrene and two dihydrophenanthrene derivatives were isolated from the diethyl ether extract of fresh rhizomes of Dioscorea communis (L.), among them a phenanthrentriol 1 reported for the first time from Dioscoreaceae family and two dihydrophenanthrene derivatives 6 and 7 reported also for the first time from Dioscorea species. The structures of isolated compounds were elucidated using UV, IR, 1D-, 2D-NMR, and MS techniques. The anticholinesterase activity of extracts and four compounds was evaluated for the first time against acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes using Ellman method. Moreover, the antioxidant activity of extracts and three compounds has been investigated using DPPH radical scavenging, ABTS cation radical decolorization, CUPRAC, reducing power and β-carotene bleaching assays.

Four pyrrolizidine alkaloids, namely 7-O-angeloyllycopsamine N-oxide 1, echimidine N-oxide 2, echimidine 3 and 7-O-angeloylretronecine 4, were isolated for the first time from the whole plant ethanolic extract of Echium confusum Coincy, through bioassay-guided approach. Their structures were determined by spectroscopic means. All the isolates compounds showed moderate activities in inhibiting AChE, with IC50 0.276-0.769.

Eleven compounds were isolated from Poraqueiba sericea stems and identified as niga-ichigoside-F1 (1), trachelosperoside B1 (2), 4-epi-niga-ichigoside (7), 19α-hydroxyasiatic acid (3), myrianthic acid (4), hyptatic acid (5), trachelosperogenin B (6), arjunolic acid (8), and trachelosperogenin E (9), secologanoside (10) and secoxyloganin (11). Compounds 1-11 were tested for their antileishmanial activities against Leishmania infantum promastigotes, 1-6 and 8-11 were tested for their cytotoxic activities on fibroblasts, 1-3, 5-6, 8-11 were evaluated for their anti-elastase and anti-acetylcholinesterase assays activities by a spectrophotometric method and 1-2, 5 and 7-10 were tested using bioautography for their β-glucosidase. No antileishmanial activity was detected; compounds 1, 2 and 11 showed a moderate cytotoxic activity with IC 50 17.7, 20.5 and 10.9 μg/mL, respectively; compounds 2, 8, 9 and 10 gave a percentage of inhibition ranging from 13 to 16% (at 50 μg/mL) and compounds 1 and 2 showed an inhibition zone on β-glucosidase and anti-acetylcholinesterase assays.

Two new sphingolipids: oxyacanthin A [(2S,3S,4R)-2-{[(2R,5E)-2-hydroxyoctadec-5-enoyl]amino}hexaeicosane-1,3,4-triol; 1] and B [(2S,3S,4R)-2-{[(2R,5E)-2-hydroxyoctadec-5-enoyl]amino}hexaeicosane-1,3,4-triol-1-O-β-D-glucopyranoside; 2], together with 1-octacosanol, β-sitosterol, β-sitosterol 3-O-β-D-glucopyranoside and luteolin 7-O-β-glucopyranoside were isolated from the methanolic extract of the whole plant of Carthamus oxyacantha. Their structures were elucidated using (1)H and (13)C NMR spectra and 2D NMR analyses (HMQC, HMBC and COSY) in combination with mass spectrometry (EI-MS, HR-EI-MS, FAB-MS and HR-FAB-MS) experiments and in comparison with the literature data of the related compounds. Both the compounds 1 and 2 showed inhibitory potential against lipoxygenase (LOX) in a concentration-dependent manner with IC50 values 83.3 ± 1.3 and 245.7 ± 1.1 µM, whereas compound 2 showed inhibition against enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with IC50 values 65.3 ± 0.1 and 93.6 ± 0.1 µM, respectively.

Garcinia species are reported to possess antimicrobial, anti-inflammatory, anticancer, anti-HIV and anti-Alzheimer's activities. This study aimed to investigate the in vitro cholinesterase enzyme inhibitory activities of garcihombronane C (1), garcihombronane F (2), garcihombronane I (3), garcihombronane N (4), friedelin (5), clerosterol (6), spinasterol glucoside (7) and 3β-hydroxy lup-12,20(29)-diene (8) isolated from Garcinia hombroniana, and to perform molecular docking simulation to get insight into the binding interactions of the ligands and enzymes. The cholinesterase inhibitory activities were evaluated using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. In this study, compound 4 displayed the highest concentration-dependent inhibition of both AChE and BChE. Docking studies exhibited that compound 4 binds through hydrogen bonds to amino acid residues of AChE and BChE. The calculated docking and binding energies also supported the in vitro inhibitory profiles of IC50. In conclusion, garcihombronanes C, F, I and N (1-4) exhibited dual and moderate inhibitory activities against AChE and BChE.

In a bioassay-guided search for acetylcholinesterase (AChE) inhibitors from Chinese natural resources, eight isoquinoline alkaloids, tetrahydropalmatine (1), corydaline (2), protopine (3), berberine (4), palmatine (5), jatrorrhizine (6), coptisine (7) and dehydrocorydaline (8), were isolated from the methanolic extract of the tubers of Corydalis yanhusuo. Structures of these compounds were identified by spectroscopic techniques. Compounds 4-8 inhibited AChE activity in a dose-dependent manner, and the IC₅₀ values were 0.47 ± 0.01, 0.74 ± 0.06, 2.08 ± 0.09, 1.01 ± 0.03 and 0.62 ± 0.05 µM, respectively. Structure-activity relationship analysis suggested that aromatisation at ring C, as well as substitutions at C-2, C-3, C-9, C-10 and C-13 affect the AChE activity of protoberberine alkaloids.

A new triterpenoid 3alpha-hydroxy-ursane-5-ene (1) and a known steroid stigma sterol (2) have been isolated for the first time from the fruit of Rhazya stricta. The structures of these compounds were elucidated and identified by spectral studies. The crude ethanolic extract of R. stricta fruit has led to the determination of good results of antibacterial, lipoxygenase and acetylcholinesterase activities. In addition, we also reported the acetylcholinesterase activity of stigma sterol (2) isolated from this plant. Stigma sterol (2) was found to be an acetyl-cholinesterase inhibitor with IC(50) at a concentration of 644.0 +/- 11.75 microM. Eserine [(-)-physostigmine, IC(50) = 61 nM)] was used as a positive control.