Chemical constituents from the leaves of Elaeocarpus floribundus

Phytotoxicity and Identification of Active Compounds from Elaeocarpus floribundus Blume Plant for Controlling Weeds

Phytotoxic compounds isolated and identified from different plants have the ability to use as plant-based herbicides. Phytotoxic chemicals may be essential to weed management and environmental protection in order to reduce the indiscriminate use of synthetic pesticides. It has been reported that Elaeocarpus floribundus plant possesses phytotoxic compounds. The leaf extracts of this species demonstrated significant growth inhibition against the tested plants (dicot plant lettuce and plant monocot timothy) and inhibition was dose- and species-dependent pattern. Two phytotoxic compounds were separated using different purifications methods and identified as compounds 1 and 2. All phytotoxic compounds displayed potent growth limitation against the tested species (cress). The compound concentrations needed for the inhibition of 50% growth (IC50 value) of tested species ranged from 1.06 to 8.53 µM (micromolar). Findings of this research suggest that these compounds might be responsible for the phytotoxicity of Elaeocarpus floribundus plant. The results of this study may be helpful for the development of natural herbicide to control weeds.

Noncytotoxic 16,23-epoxycucurbitacin-type triterpenoids from Elaeocarpus hainanensis

Phytochemical investigation of methanol extract from Elaeocarpus hainanensis Oliv. leaves and twigs led to the isolation and structural determination of three 16,23-epoxycucurbitacin-type triterpenoids, including a new hydroperoxide, 16α,23α-epoxy-3β,20β-dihydroxy-24α-hydroperoxy-10αH,23βH-cucurbit-5,25-dien-11-one (elahainencin A, 1), and two known analogs (2 and 3). Their chemical structures were determined by the spectroscopic analyses, including 1 D-, 2 D NMR and HR ESI MS spectra. Compound 1 represents a cucurbitacin derivative incorporating a hydroperoxide. In addition, these isolated compounds have been found to be noncytotoxic when tested in vitro against five human cancer cell lines (A549, T24, 8505, Huh-7 and SNU-1) by using the SRB method.

A new cucurbitane - type triterpenoid from the bark of Elaeocarpus hygrophilus Kurz

A new cucurbitacin, 3β-(β-D-glucopyranosyloxy)-5β,6β:16α,23α-diepoxycucurbit-24-en-11-one or hygrocucurbin A (1), along with two known compounds, including 3β-(β-D-glucopyranosyloxy)-16α,23α-epoxycucurbita-5,24-dien-11-one (2) and (+)-lyoniresinol (3), were isolated from the bark of Elaeocarpus hygrophilus. Their chemical structures were elucidated by spectroscopic NMR, HR-IDA- TOF-MS analysis, and by comparison with the spectral data of corresponding compounds in the literature. Two cucurbitacins (1) and (2) were evaluated for their α-glucosidase inhibitory activity and cytotoxic against KB, MCF-7, Hep G2, and A549 cancer cell lines. For the α-glucosidase inhibitory activity, compound 1 showed an equivalent effect (IC50 197.4 ± 4.1 µM) compared to the acarbose, a positive control (IC50 208.5 ± 4.7 µM). And for the cytotoxicity, 2 was inactive while 1 was slightly sensitive against KB cells (IC50 233.3 ± 2.5 µM).

Identification of four allelopathic compounds including a novel compound from Elaeocarpus floribundus Blume and determination of their allelopathic activity

Allelopathic compounds can play a vital role in protecting the environment from pollution by synthetic herbicides. Compounds isolated from plant species with allelopathic potential can be used as natural herbicides to control weeds and help reduce environmental pollution. Elaeocarpus floribundus has been reported to contain allelopathic compounds. Aqueous methanolic extracts of the leaves of this plant showed strong growth inhibitory potential against two test species (monocotyledonous Italian ryegrass and dicotyledonous alfalfa) in plants- and dose-dependent technique. Several extensive chromatographic separations of the E. floribundus leaf extracts yielded four active compounds 1, 2, 3, and 4 (novel compound). All the identified compounds showed strong growth inhibitory potential against cress. The concentrations caused for 50% growth limitation (I₅₀ values) of the cress seedlings were in the range 500.4-1913.1 μM. The findings indicate that the identified compounds might play a pivotal function in the allelopathic potential of E. floribundus tree. This report is the first on elaeocarpunone and its allelopathic potential.

Myricitrin - a flavonoid isolated from the Indian olive tree (Elaeocarpus floribundus) - inhibits Monoamine oxidase in the brain and elevates striatal dopamine levels: therapeutic implications against Parkinson's disease

Flavonoids exhibit several biological activities including inhibition of Monoamine oxidase (MAO), an enzyme that metabolizes several neurotransmitters. Thus, MAO inhibitors are well included in traditional therapeutic practices to fine-tune neuromotor behavior. This study aims to isolate flavonoids from a less explored plant of northeast India, named Indian olive (Elaeocarpus floribundus; Ef, family Elaeocarpaceae), and evaluate their MAO inhibitory properties. Four flavonoids from Ef leaf extract, namely, myricitrin, mearnsitrin, myricetin, and mearnsetin, are taken into consideration. Spectrofluorimetric assay is carried out to determine the MAO inhibitory properties. Next, in vitro and in vivo toxicity studies are performed in neuronal cell line and Drosophila, respectively. Furthermore, MAO inhibition by the selected compounds and their effect on dopamine levels are examined in the mouse brain. We evaluated the therapeutic potential in a mouse model of Parkinson's disease (PD) in terms of behavior, neurotransmitter levels, and dopaminergic neuronal loss. In an in vitro setup, all four compounds inhibited total MAO, whereas myricitrin exhibited some selectivity against MAO-B at 100 μM. Myricitrin and mearnsitrin exhibited no toxicity, in vitro or in vivo. However, only myricitrin inhibited MAO in the mouse brain and elevated dopamine levels. Myricitrin was able to attenuate motor incoordination in the mouse model of PD and improved dopamine levels in the striatum.

Elaeocarpus floribundus Bl. seeds as a new source of bioactive compounds with promising antioxidant and antimicrobial properties

The fruits of Elaeocarpus floribundus Bl. (Elaeocarpaceae) are edible and are normally prescribed for treatment of diseases. The medicinal uses of the fruit create considerable quantities of seeds as wastes. In an attempt to valorise this biomass, we studied the antimicrobial and antioxidant activities of the ethanolic seed extract. The extract inhibited the growth of the tested pathogens and was also a very strong scavenger of DPPH free radicals. Consequently, the extract was phytochemically investigated and this study reports the initial isolation of five phenolic compounds from this source. The structures of the isolated compounds were elucidated by spectra analyses including HR-ESI-MS, 1D and 2D NMR experiments. The isolated compounds exhibited a wide range of antimicrobial activities against the tested pathogens. Gallic acid (4) showed the most activity against Bacillus subtilis with a minimum inhibitory concentration (MIC) value of 30 µg/mL, while the MIC values of the antimicrobial standards range between 10 and 35 µg/mL. Compound 4, crude ethanolic extract, and the ethyl acetate fraction were more a potent free radical scavenger of DPPH compared to ascorbic acid. Hence, the seeds of E. floribundus could be considered as a new source of bioactive compounds for pharmaceutical and food-related industries.