A new 4-arylflavan from the pericarps of Horsfieldia motleyi displaying dual inhibition against α-glucosidase and free radicals

Phytochemical Analysis, Antioxidant Activity and Bioassay-Guided Isolation of Acetylcholinesterase and Butyrylcholinesterase Inhibitors from Horsfieldia polyspherula Bark (Myristicaceae)

Alzheimer's disease (AD) is a neurodegenerative condition brought on by aging and characterised by progressive decline in cognitive function and abnormalities in the central cholnergic system. β-amyloid deposits, neurofibril tangle aggregation, oxidative stress or reduced level of acetylcholine are a few causes that have been linked to AD. In this study, the bioassay-guided isolation from ethyl acetate (EtOAc) extract of Horsfieldia polyspherula bark led to the isolation of nine compounds namely, 16-phenylhexadecanoic acid (1), undecylbenzene (2), 3,4-dihydroxybenzoic acid (3), dodecanoic acid (4), tetradecanoic acid (5), pentadecanoic acid (6), 1-tridecene (7), stigmasterol (8) and trimyristin (9). Phytochemical analysis revealed the presence of flavonoids, steroids, lignin, alkaloids, phytosterol and triterpenoids. The DPPH scavenging activity of EtOAc extract was related to the phenolic content (116.67 ± 16.98 GAE mg/g) and other non-phenolics such as lower fatty acids. Meanwhile, the DPPH scavenging activity was found to be concentration-dependent and correlated with both flavonoid and phenolic content. Furthermore, EtOAc and methanol (MeOH) extracts of H. polyspherula bark showed significant inhibitory activity at 100 μg/mL on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), with EtOAc extract showing 77.2% and 64.1% inhibition and MeOH extract showing 37.5% and 39.2% inhibition, respectively. Additionally, the IC50 for BuChE and AChE of the EtOAc extract were found to be effective, with 15.41 ± 0.78 μg/mL and 7.67 ± 0.13 μg/mL, respectively. Compound 1 exhibited dual inhibition of 40.99 ± 1.99 μM (BuChE) and 46.83 ± 2.44 μM (AChE), while compounds 2 and 3 showed IC50 values above 200 μM. This study revealed that this plant shows a significant potential as anti-cholinesterase focusing on acetylcholinesterase (AchE) and butyrylcholinesterase (BuChE). This is the first report on Horsfieldia polyspherula and their biological activity.

Investigations of Antibacterial, Antioxidant, and Antidiabetic Potential of Extract and Its Active Fractions from the Leaves of Horsfieldia spicata (Roxb.) J. Sinclair

This study was undertaken to analyse the potential bioactivities including antibacterial, antioxidant and antidiabetic derived from the methanolic extract and the column chromatography ethyl acetate fraction (AcOEt Fr) of Horsfieldia spicata leaves. Methanolic extract and 4 other fractions was calculated for total phenol and flavonoid contents along with tested for antibacterial, antioxidant and antidiabetic properties. Interestingly, the AcOEt Fr had the highest value for total flavonoid content and the best antioxidant, and antidiabetic activities. Therefore, the AcOEt Fr was further separated using column chromatography technique for obtaining 9 selected fractions namely fraction 1 (F1) - fraction 9 (F9) which were further tested. The results showed that the AcOEt column chromatography fractions namely F2, F3, F4 and F6 had the best clear inhibition antibacterial value against all bacterial tested. In addition, these fractions also exhibited better Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) values than others. Antioxidant, 2,2-diphenylpicrylhydrazyl (DPPH) assayed indicated that AcOEt Fr had the strongest IC50 value of 47.30 μg/mL. Further, F4 column chromatography fraction showed the best inhibition against α-Glucosidase enzyme related to antidiabetic activity with an IC50 value of 6.11 μg/mL. Liquid chromatography tandem-mass spectrometry (LC/MS/MS) analysis identified that F4 derived from AcOEt fraction had several compounds belonging to the flavonoid and phenolics such as 3',5-dihydroxy-7,4'-dimethoxyflavone, 5,7-dihydroxy-3-(4'-hydroxybenzyl)chromone, and Kadsurenin I.

Chemical composition of three Malaysian Horsfieldia essential oils

This study aims to assess the chemical compositions of the essential oils from three Horsfieldia species namely H. fulva Warb., H. sucosa Warb. and H. superba Warb., which are found in Malaysia. The essential oils were derived from the samples through hydrodistillation which were then characterised by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Based on the findings, the H. fulva, H. sucosa and H. superba essential oils represented 98.2%, 98.7% and 98.5% of the total oils, respectively. The major component of H. fulva oil was identified to be germacrene D (20.8%), H. sucosa oil mainly contained α-cadinol (17.5%), whereas H. superba oil was rich in δ-cadinene (18.2%). To the best of our knowledge, this is the first study of the composition of the essential oils from these selected Horsfieldia species.

Cytotoxicity of acylphloroglucinol derivatives from the fruits of Horsfieldia irya

Four new acylphloroglucinol derivatives 1, 3, 5 and 13 were isolated from the fruits of Horsfieldia irya, and in addition, thirteen known compounds were also discovered. All compounds were evaluated for cytotoxicity against HeLa and HCT116 cell lines, as well as normal cells (Vero cells). Compound 13 showed cytotoxicity against HeLa and HCT116 cell lines with IC₅₀ values of 4.53 ± 0.05 and 4.53 ± 0.16 μg/mL, respectively, and showed less activity against normal cells (IC₅₀ = 13.38 ± 0.75 μg/mL). Compound 13 may be useful for the development of anticancer agents. It was found that decanoyl side chain may be necessary for the cytotoxicity. The chemical structures of all isolated compounds were elucidated using spectroscopic methods including 1 D-NMR, 2 D-NMR, MS and IR data.