Azadirachtin, as a botanical insecticide, is a highly oxidized limonoid triterpenoid existing in the seeds of Azadirachta indica. However, due to the low content in the seeds, the production of azadirachtin by seed extraction has low yield. Chemical synthesis of azadirachtin is characterized by complex process and low yield. Synthetic biology provides an alternative for the supply of azadirach-tin. In this study, two oxidosqualene cyclases AiOSC1 and MaOSC1 respectively derived from A. indica and Melia azedarach were identified in yeast. A yeast strain producing tirucalla-7,24-dien-3β-ol was constructed by integration of AiOSC1, Arabidopsis thaliana-derived squalene synthase gene(AtAQS2), and Saccharomyces cerevisiae-derived truncated 3-hydroxy-3-methyl-glutaryl coenzyme A reductase gene(PgtHMGR) into the delta site of yeast. Then, the function of MaCYP71BQ5 was successfully verified in yeast after this gene was introduced into the constructed yeast strain. This study not only laid a foundation for the biosynthesis of tirucalla-7,24-dien-3β-ol, but also provided a chassis cell for the functional identification of cytochrome oxidases(CYP450 s) in azadirachtin biosynthesis pathway.
Azadirachta ; Limonins ; Saccharomyces cerevisiae/genetics* ; Triterpenes

Fifteen limonoids were isolated from 95% ethanol extracts of the dry seeds of neem( Azadirachta indica) by various column chromatography techniques including silica gel,Pharmadex LH-20 gel and ODS resin. Based on spectroscopic analysis,their structures were determined as nimbocinol( 1),17β-hydroxynimbocinol( 2),1α,3α,7α-triacetylvilasinin( 3),7α-benzoyltrichilinin( 4),1,3-diacetyl-7-tigloyl-12-hydroxyvilasinin( 5),3-deacetylsalannin( 6),1-O-acetyl-1-detigloylsalannin( 7),2'( R),3'-dihydrosalannin( 8),2'( S),3'-dihydrosalannin( 9),2,3-dihydronimbolide( 10),6-homodesacetylnimbin( 11),gedunin( 12),7-deacetyl-7-epi-dihydrogedunin( 13),7-deacetoxy-7α-hydroxygedunin( 14) and nimbinene( 15). Compound 7 is a new natural product. 4,8,9,13 and 14 are isolated from the genus Azadirachta for the first time. Compound 2 showed inhibitory activity against Escherichia coli and Staphylococcus epidermidis,with MIC values of 32 and 128 mg·L~(-1),respectively. Compound 10 showed moderate inhibitory activity against S. epidermidis with a MIC value of 64 mg·L~(-1). Compound 11 inhibited the growth of E. coli and Pseudomonas aeruginosa,both with MIC values of 128 mg·L~(-1). Compound 15 exhibited inhibitory activity against P. aeruginosa,with a MIC value of128 mg·L~(-1).
Anti-Bacterial Agents/pharmacology* ; Azadirachta ; Escherichia coli ; Limonins ; Plant Extracts/pharmacology* ; Seeds

Microbial wound infection prolonged the hospitalization and increase the cost for wound management. Silver is commonly used as antimicrobial wound dressing. However, it causes several adverse side effects. Hence, this study was aimed to evaluate the antimicrobial efficiency of Swietenia macrophylla seed extract on clinical wound pathogens. Besides, the bioactive constituents of the seed extract were also determined. S. macrophylla seeds were extracted with methanol by maceration method. The seed extract inhibited 5 test bacteria and 1 yeast on disc diffusion assay. The antibacterial activity was broad spectrum, as the extract inhibited both Gram positive and Gram negative bacteria. On kill curve analysis, the antibacterial activity of the seed extract was concentration-dependent, the increase of extract concentration resulted in more reduction of bacterial growth. The extract also caused 99.9% growth reduction of Bacillus subtilis relative to control. A total of 21 compounds were detected in gas chromatography-mass spectrometry analysis. The predominant compounds present in the extract were oleic acid (18.56%) and linoleic acid (17.72%). In conclusion, the methanolic extract of S. macrophylla seeds exhibited significant antimicrobial activity on clinical wound pathogens. Further investigations should be conducted to purify other bioactive compounds from the seeds of S. macrophylla.
Bacillus subtilis ; Bacteria ; Bandages ; Diffusion ; Gas Chromatography-Mass Spectrometry ; Gram-Negative Bacteria ; Hospitalization ; Linoleic Acid ; Meliaceae ; Methanol ; Methods ; Oleic Acid ; Silver ; Wound Infection ; Wounds and Injuries ; Yeasts

Two new furan fragment isomerized limonoids, meliazedalides A and B (compounds 1 and 2), were isolated from the fruits of Melia azedarach Linn.. Their chemical structures were elucidated on the basis of HR-ESI-MS and 1D and 2D NMR data, which belonged to nimbolinin- and trichilin-class, respectively. Compound 2 exhibited weak inhibitory effect on NO production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages with IC being 37.41 μmol·L.
Animals ; Anti-Inflammatory Agents ; chemistry ; isolation & purification ; pharmacology ; Drugs, Chinese Herbal ; chemistry ; Fruit ; chemistry ; Limonins ; chemistry ; isolation & purification ; pharmacology ; Macrophages ; drug effects ; metabolism ; Melia azedarach ; chemistry ; Mice ; Molecular Structure ; Nitric Oxide ; metabolism ; RAW 264.7 Cells

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

Two new limonoids, 12-ethoxynimbolinins G and H (compounds 1 and 2), and one known compound, toosendanin (Chuanliansu) (compound 3), were isolated from the bark of Melia toosendan. Their structures were elucidated by spectroscopic analysis and X-ray techniques. The absolute configuration of toosendanin (3) was established by single-crystal X-ray diffraction. Compounds 1-3 were evaluated for their cytotoxicity against five tumor cell lines.
Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Limonins ; isolation & purification ; Melia ; chemistry ; Molecular Structure ; Plant Bark ; chemistry ; Plant Extracts ; chemistry ; isolation & purification ; pharmacology ; X-Ray Diffraction

OBJECTIVEMyanmar has a long history of using medicinal plants for treatment of various diseases. To the best of our knowledge there are no previous reports on antiglycation activities of medicinal plants from Myanmar. Therefore, this study was aimed to evaluate the antioxidant, antiglycation and antimicrobial properties of 20 ethanolic extracts from 17 medicinal plants indigenous to Myanmar.

METHODSIn vitro scavenging assays of 2,2-diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), superoxide (SO) radicals were used to determine the antioxidant activities. Folin-Ciocalteu's method was performed to determine the total phenolic content. Antiglycation and antimicrobial activities were detected by bovine serum albumin-fluorescent assay and agar well diffusion method.

RESULTSTerminalia chebula Retz. (Fruit), containing the highest total phenolic content, showed high antioxidant activities with inhibition of 77.98% ± 0.92%, 88.95% ± 2.42%, 88.56% ± 1.87% and 70.74%± 2.57% for DPPH, NO, SO assays and antiglycation activity respectively. It also showed the antimicrobial activities against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans with inhibition zone of 19, 18, 17, 25 and 15 mm, respectively. Garcinia mangostana Linn. showed the strongest activities for SO and antiglycation assays with inhibition of 93.68% ± 2.63% and 82.37% ± 1.78%. Bark of Melia sp. was the best NO radical scavenger with inhibition rate of 89.39%± 0.60%.

CONCLUSIONThe results suggest that these plants are potential sources of antioxidants with free radical-scavenging and antiglycation activities and could be useful for decreasing the oxidative stress and glycation end-product formation in glycation-related diseases.

Anti-Bacterial Agents ; analysis ; pharmacology ; Anti-Infective Agents ; analysis ; pharmacology ; Antioxidants ; analysis ; pharmacology ; Bacteria ; drug effects ; growth & development ; Biphenyl Compounds ; metabolism ; Candida albicans ; drug effects ; growth & development ; Fruit ; Garcinia ; chemistry ; Glycation End Products, Advanced ; metabolism ; Humans ; Magnoliopsida ; chemistry ; Medicine, Traditional ; Melia ; chemistry ; Myanmar ; Nitric Oxide ; metabolism ; Oxidative Stress ; drug effects ; Phenols ; analysis ; pharmacology ; Phytotherapy ; Picrates ; metabolism ; Plant Bark ; Plant Extracts ; chemistry ; pharmacology ; Plants, Medicinal ; Superoxides ; Terminalia ; chemistry

Eight limonoids were isolated from 95% ethanol extracts of neem(Azadirachta indica) seeds by various chromatographic methods. By comparison of their spectroscopic data with those reported in the literatures, these limonoids were determined as salannin(1), 1-detigloyl-1-isobutylsalannin(2), salannol-3-acetate(3), salannol(4), spirosendan(5), 1-detigloyloxy-3-deacetylsalannin-1-en-3-one(6), nimbin(7) and 6-deacetylnimbin(8). Compounds 2 and 5 were firstly isolated from this genus and 5 represented the only example of its type. And 6 is a new natural product. 6 showed inhibitory activity against HeLa and HL-60 cells, with IC₅₀ of(21.61±4.37) and(27.33±5.74) μmol·L⁻¹, respectively. Both 7 and 8 mildly inhibited the growth of HeLa cells, with IC₅₀ of (33.15±5.24) and (38.56±6.41) μmol·L⁻¹, respectively.
Azadirachta ; chemistry ; HL-60 Cells ; HeLa Cells ; Humans ; Limonins ; isolation & purification ; pharmacology ; Phytochemicals ; isolation & purification ; pharmacology ; Plant Extracts ; Seeds ; chemistry

Six dammarane-type triterpenoids, dammar-24-en-3β-ol (1), 3β-epicabraleahydroxy lactone (2), (E)-25-hydroperoxydammar-23-en-3β,20-diol (3), dammar-24-en-3β,20-diol (4), 3β-acetyl-20S,24S-epoxy-25-hydroxydammarane (5), and 3β-epiocotillol (6) were isolated from the methanolic extract of the bark of Aglaia elliptica. The chemical structure were identified on the basis of spectroscopic evidence and by comparison with those spectra previously reported. Compounds 1 – 6 were isolated first time from this plant. Compounds 1 – 6, along with a known synthetic analog, cabraleone (7) were evaluated their cytotoxic activity against P-388 murine leukimia cells in vitro. Among those compounds 3β-acetyl-20S,24S-epoxy-25-hydroxydammarane (5) showed strongest cytotoxic activity with IC₅₀ value of 8.02 ± 0.06 µM.
Aglaia* ; In Vitro Techniques ; Leukemia* ; Meliaceae ; Methanol ; Plants ; Structure-Activity Relationship*

Two new phragmalin-type limonoids orthoesters, encandollens A and B (1 and 2), were isolated from the stem barks of Entandrophragma candollei collected in Ghana. The structures of these compounds were elucidated on the basis of HR-ESI-MS, H and C NMR, HSQC, HMBC, and ROESY data. Compound 1 was a rare C-15 enolic acyl phragmalin-type limonoid orthoester. Compounds 1 and 2 exhibited weak inhibitory effects on NO production in lipopolysaccharide (LPS)-induced RAW 264.7 cells.
Animals ; Drugs, Chinese Herbal ; chemistry ; isolation & purification ; pharmacology ; Limonins ; chemistry ; isolation & purification ; pharmacology ; Macrophages ; drug effects ; metabolism ; Meliaceae ; chemistry ; Mice ; Molecular Structure ; Nitric Oxide ; metabolism ; Plant Bark ; chemistry ; RAW 264.7 Cells