Allelopathic Activity and Characterization of Allelopathic Substances from Elaeocarpus floribundus Blume Leaves for the Development of Bioherbicides

To help protect the environment as well as increase agricultural production, the use of synthetic herbicides must be reduced and replaced with plant-based bioherbicides. Elaeocarpus floribundus is a perennial, evergreen, and medium-sized plant grown in different areas of the world. The pharmaceutical properties and various uses of Elaeocarpus floribundus have been reported, but its allelopathic potential has not yet been explored. Thus, we carried out the present study to identify allelopathic compounds from Elaeocarpus floribundus. Aqueous MeOH extracts of Elaeocarpus floribundus significantly suppressed the growth of the tested species (cress and barnyard grass) in a dose- and species-dependent way. The three most active allelopathic substances were isolated via chromatographic steps and characterized as (3R)-3-hydroxy-β-ionone, cis-3-hydroxy-α-ionone, and loliolide. All three substances significantly limited the seedling growth of cress, and the compound (3R)-3-hydroxy-β-ionone had stronger allelopathic effects than cis-3-hydroxy-α-ionone and loliolide. The concentrations of the compounds required for 50% growth inhibition (I50 value) of the cress seedlings were in the range of 0.0001–0.0005 M. The findings of this study indicate that all three phytotoxic substances contribute to the phytotoxicity of Elaeocarpus floribundus.

Enhancing Methane Production from Spring-Harvested Sargassum muticum

Sargassum muticum is a brown seaweed which is invasive to Europe and currently treated as waste. The use of S. muticum for biofuel production by anaerobic digestion (AD) is limited by low methane (CH4) yields. This study compares the biochemical methane potential (BMP) of S. muticum treated in three different approaches: aqueous methanol (70% MeOH) treated, washed, and untreated. Aqueous MeOH treatment of spring-harvested S. muticum was found to increase CH4 production potential by almost 50% relative to the untreated biomass. The MeOH treatment possibly extracts AD inhibitors which could be high-value compounds for use in the pharmaceutical industry, showing potential for the development of a biorefinery approach; ultimately exploiting this invasive seaweed species.

A Synthesis of Novel Dioxapropellanes from the Knoevenagel Adducts of Acenaphthoquinone and 3-Oxo-3-arylpropionitriles in Aqueous Methanol

A highly chemoselective and regioselective method for the synthesis of dioxopropellanes developed by reaction of the Knoevenagel adducts of acenaphthoquinone (and ninhydrin) and malononitrile, with 3-oxo-3-arylpropionitriles in 70% aqueous MeOH at room temperature, is reported.

Chemical Constituents and Antioxidant Activity of a Polar Extract from Pituranthos battandieri Maire

Phytochemical investigation of the n-butanol soluble part of the aqueous-MeOH extract of the aerial parts of Pituranthos battandieri Maire collected from the region of Bechar in the south-west of Algeria, led to the isolation and structural elucidation of mannitol 1, xanthotoxol 2, 8-(6’,7’-dihydroxygeranyloxy)-psoralen 3 and isorhamnetin 3-O-ß-Dglucopyranoside (cacticin) 4. The structures were established by spectral analyses, mainly ESI-HRMS, UV and NMR experiments ( 1H, 13C, DEPT, COSY, HSQC and HMBC) and comparison with literature data. All these compounds were described for the first time from this endemic species. The free radical scavenging activity of this extract was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH• ) and hydrogen peroxide (H2O2) scavenging activity models. Antihemolytic property was performed using H2O2 induced red blood cell hemolysis model. Antiperoxidative effect was evaluated using lipid peroxidation-ammonium thiocyanate model. Both DPPH and H2O2 assays indicated antioxidant ability of n-BuOH extract of P. battandieri (BEPB), that were reflected by IC50 values 876.16±7.96 µg/mL and 603.8±71.06 µg/mL, respectively. In addition, the results of the present study clearly indicated that BEPB inhibited rat erythrocytes hemolysis induced by H2O2 in a dose dependent way with IC50 value 782.38±89.97 μg/mL. The inhibition of lipid peroxides generated from linoleic acid was recorded at IC50: 496.04±117.06 µg/mL. The antiperoxidative and the antihemolytic activities of P. battandieri appear as a consequence of synergistic interactions between active constituents among them mannitol 1, the furanocoumarins 2 and 3, and the flavonoid 4.

ASSESSING THE BIOACTIVITY AND ANTIOXIDATIVE PROPERTIES OF SOME COMPOUNDS ISOLATED FROM ABUTILON HIRTUM (LAM.)

ABSTRACTObjectives: The present study on the methanol extract of Abutilon hirtum (Lam.) [Malvaceae] afforded ten compounds. Findings from this assessmentindicated that A. hirtum leaves possessed vast potential as medicinal product especially in liver cancer treatment.Methods: Dried-powdered leaves were boiled under reflux in 10 L of petroleum ether for 8 hrs. After filtration, the solvent was evaporated; afforded15 g of petroleum ether extract followed by boiling with reflux for 8 hrs with chloroform, then filtration and the residue was evaporated to give 34 gchloroform extract. Ethyl acetate was added and refluxed for 8 hrs, then filtration and evaporation to give 31 g ethyl acetate extract. Finally the leaveswere refluxed with 10 L of 85 % aqueous MeOH, after cooling, the solution was filtered and evaporated and the residue was 210 g methanol extractthen the residue was dissolved in de-ionized water (250 ml), then the salt was removed by adding excess methanol solution (2.5 L), and finally filtered.The cytotoxicity of the isolated compounds was evaluated towards HepG2 liver-carcinoma cell line using MTT assay, the antimicrobial activity wastested using the Disc agar plate method and the total antioxidant capacity was determined according to phosphomolybdenum method.Results: The isolated compounds identified as methyl gallate, cuneataside E, bergapten, gallic acid, ellagic acid, epigallocatechin-3-O-gallate,kaempferol-3-O-α-L-rhamnoside, benzyl-1-O-β-D-glucopyranoside, 2(4-hydroxyphenyl)ethyl-O-β-D-glucopyranoside and β-sitosterol. All the isolatedcompounds are known; but they were isolated from Abutilon hirtum for the first time.Conclusion: This report may serve as a footprint concerning the biological and pharmacological activities of A. hirtum leaves.Keywords: Abutilon hirtum, Malvaceae, HepG2, Phenolics, Antioxidant.

Synthesis and Structure of a Clathrated Two-Dimensional Metal-Organic Framework: [Cd(4,4'-bpy)2(H2O)2](ClO4)2·(L)2·H2O (L = Bis(1-pyrazinylethylidene)hydrazine)

The compound [Cd(4,4'-bpy)2(H2O)2](ClO4)2·(L)2 was obtained by the reaction of Cd(ClO4)2, bis(1-pyrazinylethylidene)hydrazine (L) and 4,4'-bipyridine in aqueous MeOH. Single-crystal X-ray diffraction has revealed its two-dimensional metal-organic framework. The 2-D layers superpose on each other, giving a channel structure. The square planar grids consist of two pairs of shared edges with Cd(II) ion and a 4,4'-bipyridine molecule each vertex and side, respectively. The square cavity has a dimension of 11.817 × 11.781 Å. Two guest molecules of bis(1-pyrazinylethylidene)hydrazine are clathrated in every hydrophobic host cavity, being further stabilized by π-π stacking and hydrogen bonding. The results suggest that the hydrazine molecules present in the network serve as structure-directing templates in the formation of crystal structures.