01282nas a2200205 4500008004100000022001400041245008100055210006900136260011000205300001600315490000600331520047900337100001900816700002100835700002700856700002100883700002400904700003700928856011100965 2014 eng d a2046-206900aBiocatalyst mediated functionalization of salannin, an insecticidal limonoid0 aBiocatalyst mediated functionalization of salannin an insecticid aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUN a27661-276640 v43 a

Transformation of salannin, an insecticidal C-seco limonoid was investigated using a fungal system, Cunninghamella echinulata. Salannin was efficiently converted into two metabolites, where the C-17 furan moiety was transformed into gamma-hydroxybutenolide (salanninolide) and N-(2-hydroxyethyl)-alpha,beta-unsaturated-gamma-lactam (salanninactam) analogues. Present studies have indicated salanninolide to be a metabolite in the C-seco limonoid biosynthetic pathway.

1 aHaldar, Saikat1 aKolet, Swati, P.1 aDandekar, Devdutta, S.1 aKale, Balaji, S.1 aGonnade, Rajesh, G.1 aThulasiram, Hirekodathakallu, V. uhttps://library.ncl.res.in/content/biocatalyst-mediated-functionalization-salannin-insecticidal-limonoid-002288nas a2200265 4500008004100000022001400041245012100055210006900176260007300245300000900318490000900327520130900336653003701645653000901682653001301691653002601704653001301730653001801743100001901761700002201780700002901802700002701831700003701858856012701895 2014 eng d a0021-967300aExpedient preparative isolation and tandem mass spectrometric characterization of C-seco triterpenoids from neem oil0 aExpedient preparative isolation and tandem mass spectrometric ch aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcOCT a1-140 v13663 a

C-seco triterpenoids are widely bioactive class of natural products with high structural complexity and diversity. The preparative isolation of these molecules with high purity is greatly desirable, although restricted due to the complexity of natural extracts. In this article we have demonstrated a Medium Pressure Liquid Chromatography (MPLC) based protocol for the isolation of eight major C-seco triterpenoids of salannin skeleton from Neem (Azadirachta indica) oil. Successive application of normal phase pre-packed silica-gel columns for the fractionation followed by reverse phase in automated MPLC system expedited the process and furnished highly pure metabolites. Furthermore, eight isolated triterpenoids along with five semi-synthesized derivatives were characterized using ultra performance liquid chromatography-electrospray ionization-quadrupole/orbitrap-MS/MS spectrometry as a rapid and sensitive identification technique. The structure-fragment relationships were established on the basis of plausible mechanistic pathway for the generation of daughter ions. The MS/MS spectral information of the triterpenoids was further utilized for the identification of studied molecules in the complex extract of stem and bark tissues from Neem. (C) 2014 Elsevier B.V. All rights reserved.

10aESI(+)-quadrupole/orbitrap-MS/MS10aMPLC10aNeem oil10aPreparative isolation10aSalannin10aTriterpenoids1 aHaldar, Saikat1 aMulani, Fayaj, A.1 aAarthy, Thiagarayaselvam1 aDandekar, Devdutta, S.1 aThulasiram, Hirekodathakallu, V. uhttps://library.ncl.res.in/content/expedient-preparative-isolation-and-tandem-mass-spectrometric-characterization-c-seco-003334nas a2200277 4500008004100000022001400041245014500055210006900200260008100269300002400350490000700374520225400381653002302635653002702658653001802685653001802703100002202721700002702743700001902770700002202789700002702811700002202838700002902860700003702889856013002926 2015 eng d a1471-222900aTriterpenoid profiling and functional characterization of the initial genes involved in isoprenoid biosynthesis in neem (Azadirachta indica)0 aTriterpenoid profiling and functional characterization of the in a236 GRAYS INN RD, FLOOR 6, LONDON WC1X 8HL, ENGLANDbBIOMED CENTRAL LTDcSEP aArticle Number: 2140 v153 a

Background: Neem tree (Azadirachta indica) is one of the richest sources of skeletally diverse triterpenoids and they are well-known for their broad-spectrum pharmacological and insecticidal properties. However, the abundance of Neem triterpenoids varies among the tissues. Here, we delineate quantitative profiling of fifteen major triterpenoids across various tissues including developmental stages of kernel and pericarp, flower, leaf, stem and bark using UPLC-ESI (+)-HRMS based profiling. Transcriptome analysis was used to identify the initial genes involved in isoprenoid biosynthesis. Based on transcriptome analysis, two short-chain prenyltransferases and squalene synthase (AiSQS) were cloned and functionally characterized. Results: Quantitative profiling revealed differential abundance of both total and individual triterpenoid content across various tissues. RNA from tissues with high triterpenoid content (fruit, flower and leaf) were pooled to generate 79.08 million paired-end reads using Illumina GA.. platform. 41,140 transcripts were generated by d e novo assembly. Transcriptome annotation led to the identification of the putative genes involved in isoprenoid biosynthesis. Two short-chain prenyltransferases, geranyl diphosphate synthase (AiGDS) and farnesyl diphosphate synthase (AiFDS) and squalene synthase (AiSQS) were cloned and functionally characterized using transcriptome data. RT-PCR studies indicated five-fold and ten-fold higher relative expression level of AiSQS in fruits as compared to leaves and flowers, respectively. Conclusions: Triterpenoid profiling indicated that there is tissue specific variation in their abundance. The mature seed kernel and initial stages of pericarp were found to contain the highest amount of limonoids. Furthermore, a wide diversity of triterpenoids, especially C-seco triterpenoids were observed in kernel as compared to the other tissues. Pericarp, flower and leaf contained mainly ring-intact triterpenoids. The initial genes such as AiGDS, AiFDS and AiSQS involved in the isoprenoids biosynthesis have been functionally characterized. The expression levels of AiFDS and AiSQS were found to be in correlation with the total triterpenoid content in individual tissues.

10aAzadirachta indica10aQuantitative profiling10aTranscriptome10aTriterpenoids1 aPandreka, Avinash1 aDandekar, Devdutta, S.1 aHaldar, Saikat1 aUttara, Vairagkar1 aVijayshree, Shinde, G.1 aMulani, Fayaj, A.1 aAarthy, Thiagarayaselvam1 aThulasiram, Hirekodathakallu, V. uhttps://library.ncl.res.in/content/triterpenoid-profiling-and-functional-characterization-initial-genes-involved-isoprenoid-1