Conventional extraction of oil and azadirachtin, a botanical insecticide, from Azadirachta indica involves defatting the seeds and leaves using hexane followed by azadirachtin extraction with a polar solvent. In order to simplify the process while maintaining the yield we explored a binary extraction approach using Soxhlet extraction device and hexane and ethanol as non-polar and polar solvents at various ratios and extraction times. The highest oil and azadirachtin yields were obtained at 6 h extraction time using a 50:50 solvent mixture for both neem leaves (44.7 wt%, 720 mg(Aza)/kg(leaves)) and seeds (53.5 wt%, 1045 mg(Aza)/kg(seeds)), respectively.
Azadirachta ; Ethanol ; Limonins ; Solvents

Callophylum symingtonianum (Guttiferae), an evergreen broad-leaved tree that usually grows in hill forests, can be found distributed in the Malay Peninsula. The barks, leaves, flowers and seeds is often used medicinally to treat diarrhea and rheumatism. In the present study, we isolated two inophyllum type coumarins, 12-O-ethylinophyllum D (1) and iso-soulattrolide (2) from the stembarks of C. symingtonianum together with their antibacterial activity. The compounds were isolated by chromatographic methods on a silica gel. The structures were established by spectroscopic methods including UV, IR, (1D and 2D) NMR and mass spectrometry as well as by comparison with several literature sources. The antibacterial activity of those compounds was tested using a disc-diffusion assay against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Both compound exhibited mild inhibition against P. aeruginosa with both 111 µg/ml MIC value. Compound 2 also inhibits S. aureus with 25 µg/ml MIC value.
Bacillus cereus ; Calophyllum ; Coumarins ; Diarrhea ; Escherichia coli ; Flowers ; Forests ; Malaysia ; Mass Spectrometry ; Pseudomonas aeruginosa ; Rheumatic Diseases ; Silica Gel ; Staphylococcus aureus ; Trees

Nymphoides is an aquatic genus consisting about 50 species, of which few were accepted as traditional medicinal plants in Asia. The literature review revealed that Nymphoides species are widely used in Ayurvedic medicine as a popular drug, i.e. Tagara. They are also utilized by the traditional local healers of different Asian countries to treat various diseases, like convulsion, jaundice, fever, headache, etc. According to the in vivo and in vitro pharmacological studies, Nymphoides species have been claimed to possess major biological activities like anticonvulsant, antioxidant, hepatoprotective, cytotoxic, antitumor, etc. Biochemical profiling of different aquatic plants of this genus revealed the presence of some important phytochemicals as polyphenolic component, flavonoids, triterpenes, carbohydrates, glycosides, etc. Several valuable bioactive compounds including ephedrine, coumarin, secoiridoid glucosides, methyl quercetin, ferulic acid, foliamenthoic acid, etc. were also known to be isolated and identified from different Nymphoides species. The aim of this review is to analyze the published report based on the medicinal values of different Asian Nymphoides species, to provide the updated information about the ethnomedicinal, pharmacological as well as the phytochemical properties for the first time.

Objective: To isolate and evaluate the antimicrobial activity of the active principle(s) from the ethyl acetate (EtOAc) extract of endophytic fungus Colletotrichum gloeosporioides (C. gloeosporioides) isolated from Sonneratia apetala. Methods: Water agar technique was used to isolate the fungus, and both microscopic and molecular techniques were used for identification of the strain. Potato dextrose broth was used to grow the fungus in large-scale. Reversed-phase preparative HPLC analysis was performed to isolate the major active compound, kojic acid. The EtOAc extract and kojic acid were screened for their antimicrobial activity against two Gram-positive and two Gram-negative bacteria as well as a fungal strain using the resazurin 96-well microtitre plate antimicrobial assay. Results: The fungus C. gloeosporioides was isolated from the leaves of Sonneratia apetala. Initial identification of the fugal isolate was carried out using spore characteristics observed under the microscope. Subsequently, the ITS1-5.8S-ITS2 sequencing was employed for species-level identification of the fungus C. gloeosporioides. Five litres of liquid culture of the fungus produced approximately 610 mg of a mixture of secondary metabolites. Kojic acid (1) was isolated as the main secondary metabolite present in the fungal extract, and the structure was confirmed by 1D, 2D NMR and mass spectrometry. The EtOAc extract and compound 1 exhibited considerable antimicrobial activity against all tested microorganisms. Whilst the minimum inhibitory concentration (MIC) values from the EtOAc extract ranged between 2.4× 10