Systematic identification of chemical forms of key terpene synthase in Cinnamomum camphora / 中国中药杂志

Cinnamomum camphora is an important economic tree species in China. According to the type and content of main components in the volatile oil of leaf, C. camphora were divided into five chemotypes, including borneol-type, camphor-type, linalool-type, cineole-type, and nerolidol-type. Terpene synthase(TPS) is the key enzyme for the formation of these compounds. Although several key enzyme genes have been identified, the biosynthetic pathway of(+)-borneol, which has the most economic value, has not been reported. In this study, nine terpenoid synthase genes CcTPS1-CcTPS9 were cloned through transcriptome analysis of four chemical-type leaves. After the recombinant protein was induced by Escherichia coli, geranyl pyrophosphate(GPP) and farnesyl pyrophosphate(FPP) were used as substrates for enzymatic reaction, respectively. Both CcTPS1 and CcTPS9 could catalyze GPP to produce bornyl pyrophosphate, which could be hydrolyzed by phosphohydrolase to obtain(+)-borneol, and the product of(+)-borneol accounted for 0.4% and 89.3%, respectively. Both CcTPS3 and CcTPS6 could catalyze GPP to generate a single product linalool, and CcTPS6 could also react with FPP to generate nerolidol. CcTPS8 reacted with GPP to produce 1,8-cineol(30.71%). Nine terpene synthases produced 9 monoterpene and 6 sesquiterpenes. The study has identified the key enzyme genes responsible for borneol biosynthesis in C. camphora for the first time, laying a foundation for further elucidating the molecular mechanism of chemical type formation and cultivating new varieties of borneol with high yield by using bioengineering technology.

Chemical constituents from the leaves of Cinnamomum camphora var. linaloolifera and their anti-inflammatory activities / 中国中药杂志

Thirteen compounds were isolated and purified from the leaves of Cinnamomum camphora by the macroporous resin,silica gel,and Sephadex LH-20 column chromatographies. Those compounds were further identified by IR,UV,MS,and NMR techniques:( 2 S)-1-( 3″,4″-methylenedioxy phenyl)-3-( 2',6'-dimethoxy-4'-hydroxyphenyl)-propan-2-ol( 1),( 2 R,3 R)-5,7-dimethoxy-3',4'-methylenedioxy flavanol( 2),9-hydroxysesamin( 3),sesamin( 4),piperitol( 5),kobusin( 6),(-)-aptosimon( 7),acuminatolide( 8),1β,11-dihydroxy-5-eudesmene( 9),lasiodiplodin( 10),vanillin( 11),p-hydroxybenzaldehyde( 12),and p-hydroxybenzoic acid ethyl ester( 13). Compound 1 was a novel compound,and compounds 2,6,7,9 and 10 were isolated from Cinnamomum plants for the first time. Compounds 4,7 and 10 were found to possess good inhibitory effect on IL-6 production in LPS-induced BV2 cells at a concentration of 20 μmol·L-1 in the in vitro bioassay,with inhibition rates of 51. 26% ± 4. 13%,67. 82% ± 3. 77% and85. 81%±1. 19%,respectively.

Cloning and expression analysis of 5-phosphomevalonate kinase gene (CcPMK) in Cinnamomum camphora / 中国中药杂志

The 5-phosphomevalonate kinase(PMK) is a key enzyme in mevalonate(MVA) pathway which reversibly catalyzes the phosphorylation of mevalonate 5-phosphate(MVAP) to form mevalonate-5-diphosphate(MVAPP) in the presence of ATP and divalent metal ion such as Mg~(2+). In this research, on the basis of the transciptome database of Cinnamomum camphora, the PMK was cloned by cDNA from C. camphora, and was named CcPMK(GenBank number KU886266). The ORF of CcPMK was composed of 1 545 bp, encoding 514 amino acids. The bioinformatics analysis of CcPMK indicated that the molecular weight of the encoded protein was 56.14 kDa, with a theoretically isoelectric point of 7.64, and there was no signal peptide and transmembrane structure in putative protein. By multiple sequence alignment and phylogenetic tree analysis, we found that similarity between CcPMK and PMK amino acid sequence of other plants was as high as 75%. Among the similar sequences, 45% of them belonged to the alpha helix, while 16% belonged to the beta strand. CcPMK obtained 3 PMK protein family motifs and 1 ATP binding site Gly-Leu-Gly-Ser-Ser-Ala-Ala, and its 3 D structure contained a catalytic pocket structure, proving CcPMK as a member of PMK gene family. The result of phylogenetic tree showed that CcPMK was closely related to monocotyledon plants such as Phonenix dactylifera. The results of the Real-time PCR indicated that the expression level of CcPMK in borneol type was higher than that in linalool type, cineol type, iso-nerolidol type and camphor type. CcPMK expressed highest in roots and lowest in branches. Our results revealed that the expression level of CcPMK was different among five chemical types and different plant tissues, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.

Cloning and expression analysis of 3-hydroxy-3-methylglutaryl coenzyme A reductase (CcHMGR) genes in Cinnamomum camphora (L.) Presl / 药学学报

3-Hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) is the first rate-limiting enzyme of terpenoid biosynthesis in the mevalonic acid pathway (MVA) pathway. It is an important regulatory site in terpenoids metabolism pathway in the cytoplasm. According to the transcriptome database of Cinnamomum camphora, two HMGRs named CcHMGR1 (GenBank: MN163055) and CcHMGR2 (GenBank: MN163056) were cloned by cDNA from C. camphora. The ORF of CcHMGR1 and CcHMGR2 is composed of 1 689 bp and 1 683 bp, respectively, encoding 562 and 560 amino acids. The bioinformatics analysis of CcHMGR1 and CcHMGR2 indicated that the molecular weight of the encoded protein is 59.819 kDa and 59.397 kDa, with a theoretically isoelectric point of 8.20 and 8.61, respectively. There are 2 transmembrane structures without signal peptide existing in the encoded amino acid of CcHMGRs. The analysis of sequence alignment and phylogenetic tree showed that theCcHMGRs belonged to the HMGR family. The camphor is divided into five chemitypes, according to the main chemical compoundsin C. camphora. The results of the real time PCR indicated that the expression level of CcHMGRs in Cineol type was higher than that in Linalool type, iso-nerolidol type, Camphor type and Borneol type. CcHMGRs expressed highest in roots and lowest in branches. In this study, the cDNA full length of CcHMGRs were cloned from C. camphora for the first time. Our results revealed that the expression level of CcHMGRs were different among five chemical types and different plant tissues, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.

Chemical composition and larvicidal activities of essential oil of Cinnamomum camphora (L. ) leaf against Anopheles stephensi

Abstract INTRODUCTION Anopheles stephensi is the main malaria vector in Southeast Asia. Recently, plant-sourced larvicides are attracting great interests. METHODS: The essential oil was extracted from the leaf of Cinnamomum camphora (L.), and a bioassay was conducted to determine the larvicidal efficacy. The chemical composition of the essential oil was determined by GC-MS analysis. RESULTS: The oil showed strong, dose-dependent larvicidal activities. The onset of larvicidal efficiency was rapid. The LC50 and LC95 were determined as 0.146% and 1.057% at 1 h, 0.031% and 0.237% at 12 h, 0.026% and 0.128% at 24 h, respectively. The oil contains 32 compounds. CONCLUSIONS The essential oil of C. camphora leaf has an excellent larvicidal potential for the control of A. stephensi.

Cloning and expression analysis of 1-deoxy-D-xylulose-5-phosphate reductoisomerase gene (CcDXR1)in Cinnamomum camphora (L.) Presl / 药学学报

1-Deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) is the second rate-limiting enzyme of terpenoid biosynthesis in the methylerythritol-4-phosphate pathway. According to the transcriptome database of Cinnamomum camphora, the DXR cDNA was cloned by rapid amplification of cDNA ends (RACE) from C. camphora, and was named CcDXR1 (GenBank number:KU886266). The ORF of CcDXR1 is composed of 1 413 bp, and it encodes 470 amino acids. The bioinformatics analysis suggests that the molecular weight of the encoded protein is 51.1 kD and the theoretically isoelectric point is 6.62, and there is no signal peptide and transmembrane structure in putative protein. The analysis of sequence alignment and phylogenetic tree showed that the CcDXR1 belonged to the DXR family. The results of the realtime PCR indicated that expression level of CcDXR1 in mature leaves was higher than tender leaves, which in roots was similar to leaves and the lowest in branches. The camphor is divided into five chemotypes, according to the main chemical compounds in C. camphora. It also showed that the expression level of CcDXR1 in borneol C. camphora was highest than that in cineol, iso-nerolidol, camphor and linalool. Our results revealed that the expression level of CcDXR1 exhibits diversity among plant tissues, growth periods and five chemical types, and the research provides foundation for further study of the terpenoids biosynthetic pathway in C. camphora.

Cloning and expression analysis of 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase gene in Cinnamomum camphora / 中国中药杂志

The 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase was the fourth key enzymes in plant terpenoid biosynthesis pathway of methyl erythritol phosphate pathway(MEP). According to the study of Cinnamomum camphora transcriptome data,we abtained the 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase gene using RT-PCR,and named CcCMK1,then deposited it in GeneBank(Accession number： Ku376098).Bioinformatics analysis showed the open reading frame (ORF) of the CcCMK1 was 1 212 bp.The putative protein encoded 403 amino acids,and its molecular weight was 44.46 kDa and theoretically isoelectric point was 4.99.Transmembrane structure analysis showed that there was no transmembrane structure. Signal peptide analysis showed that it was a non secretory protein, and there was no signal peptide. The subcellular localization showed that the chloroplast was located in the chloroplast.Analysis of the expression of CcCMK1 gene in five chemotypes of C. camphora using Real-time PCR showed its expression level was highest in C. longepaniculatum, and the lowest in Borneol camphor.This research provided a basis for characterizing the key enzyme genes of terpenoid biosynthetic pathway in C. camphora.

GC-MS Analysis of Essential Oil from Fruits of Cinnamomum camphora chvar. Borneol / 中国中医药信息杂志

Objective To analyze and identify the chemical constituents of essential oil from the fruits of Cinnamomum camphora chvar. Borneol. Methods The essential oil from the fruits was extracted by steam distillation and its chemical constituents were analyzed and identified by GC-MS. Results Fifty compounds were separated, and 42 kinds of which accounting for 99.536% were identified. D-borneol was the most abundant compound, of which the amount was 50.684%of the total constituents. Conciusion This present study demonstrated higher content of natural D-borneol, providing scientific basis for further exploration and utilization of the fruits of Cinnamomum camphora chvar. Borneol.

Identificação de plantas hospedeiras da broca do abacate, Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) no Rio Grande do Sul / Identification of host plants of the avocado borer, Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) in Rio Grande do Sul

Frutos de Nectandra megapotamica Mez e de Cinnamomum camphora (L.) (Lauraceae) foram coletados no Rio Grande do Sul, em 2004. Nove espécies pertencentes a cinco famílias de insetos foram coletadas: duas espécies de Drosophila (Diptera: Drosophilidae), seis espécies de Coleoptera: Heilipus sp. e Conotrachelus sp. (Curculionidae), Hypothenemus sp. (Scolytidae) e três espécies de Carpophilus (Nitidulidae), e uma de Lepidoptera (Elachistidae). Os espécimes pertencentes à família Elachistidae foram identificados como Stenoma catenifer Walsingham, a broca do abacate. S. catenifer emergiu do início de abril até meados de maio. A infestação nos frutos foi baixa. Duas novas plantas hospedeiras dessa praga foram identificadas.

Fruits of Nectandra megapotamica Mez and Cinnamomum camphora (L.) (Lauraceae) were collected in Rio Grande do Sul, Brazil, in 2004. Species of five families of insects were found inside the fruits: two fly species (Diptera: Drosophilidae: Drosophila spp.), six beetle species, Heilipus sp., Conotrachelus sp. (Curculionidae), Hypothenemus sp. (Scolytidae) and three species of Carpophilus (Nitidulidae), and moths (Lepidoptera: Elachistidae). The moth especimes were identified as Stenoma catenifer Walsingham, the avocado borer. The occurrence of the moth was predominant from early April until middle May. The natural larval infestation level was low. Two new host plant of the pest were identified.