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Xin Fang, Jian-Xu Li, Jin-Quan Huang, You-Li Xiao, Peng Zhang, Xiao-Ya Chen
Terpene synthases (TPSs) are responsible for the extremely diversified and complex structure of terpenoids. Amorpha-4,11-diene synthase (ADS) has a high (90%) fidelity in generating the sesquiterpene precursor for biosynthesis of artemisinin, an antimalarial drug, however, little is known about how active site residues of ADS involved in the carbocation rearrangement and cyclization reactions. Here, we identify seven residues that are key to most of the catalytic steps in ADS. By structural modeling and amino acid sequence alignments of ADS with two functionally relevant sesquiterpene synthases from Artemisia annua, we performed site-directed mutagenesis and found that a single substitution, T296V, impaired the ring closure activity almost completely, and tetra-substitutions (L374Y/L404V/L405I/G439S) led to an enzyme generating 80% monocyclic bisabolyl-type sesquiterpenes, whereas a double mutant (T399L/T447G) showed compromised activity in regioselective deprotonation to yield 34...
May 19, 2017: Biochemical Journal
Adrian Arendowski, Tomasz Ruman
INTRODUCTION: European yew (Taxus baccata) is a plant known to man for centuries as it produces many interesting and important metabolites. These chemical compounds were repeatedly analysed by various analytical techniques, but none of the methods used so far allowed the localisation of the chemical compounds within the tissue and also correlation between plant morphology and its biochemistry. OBJECTIVE: Visualisation of the spatial distribution of yew metabolites with nanoparticle-based mass spectrometry imaging...
May 19, 2017: Phytochemical Analysis: PCA
A L Casey, T J Karpanen, B R Conway, T Worthington, P Nightingale, R Waters, T S J Elliott
BACKGROUND: Chlorhexidine (CHG) penetrates poorly into skin. The purpose of this study was to compare the depth of CHG skin permeation from solutions containing either 2% (w/v) CHG and 70% (v/v) isopropyl alcohol (IPA) or 2% (w/v) CHG, 70% (v/v) IPA and 2% (v/v) 1,8-cineole. METHODS: An ex-vivo study using Franz diffusion cells was carried out. Full thickness human skin was mounted onto the cells and a CHG solution, with or without 2% (v/v) 1,8-cineole was applied to the skin surface...
May 17, 2017: BMC Infectious Diseases
Sana Ghrab, Mabrouk Eloussaief, Stéphanie Lambert, Samir Bouaziz, Mourad Benzina
Essential oils from aromatic plants are currently mentioned as suitable tools for excellent protection of stored grains from insect pest attacks. The present work aimed to study the processes of the synthesis insecticidal formulation with clay. The active terpenic compounds of essential oil of Eucalyptus globulus (Eg) were fixed in the palygorskite by adsorption process. Two sample types of palygorskites were used: raw and organo-palygorskite. The palygorskite clays were characterized by different physicochemical techniques including X-ray diffraction (XRD), Fourier transform infrared (FTIR) analyses, thermogravimetric analysis (TG), differential thermal analysis (DTA), Brunauer-Emmet-Teller (BET), and scanning electron microscope (SEM)...
May 13, 2017: Environmental Science and Pollution Research International
Jie Li, Dan Hu, Xiaoli Song, Tao Han, Yonghong Gao, Yanwei Xing
Arrhythmia is a disease that is caused by abnormal electrical activity in the heart rate or rhythm. It is the major cause of cardiovascular morbidity and mortality. Although several antiarrhythmic drugs have been used in clinic for decades, their application is often limited by their adverse effects. As a result, natural drugs, which have fewer side effects, are now being used to treat arrhythmias. We searched for all articles on the role of biologically active ingredients from natural drug treatments for arrhythmias in different mechanisms in PubMed...
2017: BioMed Research International
Yuri Pinheiro Alves de Souza, Fábio Faria da Mota, Alexandre Soares Rosado
We report here the 3,586,065-bp draft genome of Geobacillus sp. LEMMY01, which was isolated (axenic culture) from a thermophilic chemolitoautotrophic consortium obtained from the site of a burning grass pile. The genome contains biosynthetic gene clusters coding for secondary metabolites, such as terpene and lantipeptide, confirming the biotechnological potential of this strain.
May 11, 2017: Genome Announcements
C Wlodek, C M Penfold, J F Bourke, M M U Chowdhury, S M Cooper, S Ghaffar, C Green, C R Holden, G A Johnston, A A Mughal, C Reckling, R A Sabroe, N M Stone, D Thompson, S M Wilkinson, D A Buckley
BACKGROUND: There is a significant rate of sensitisation worldwide to the oxidised fragrance terpenes limonene and linalool. Patch testing to oxidised terpenes is not routinely carried out; the ideal patch test concentration is unknown. OBJECTIVES: To determine the best test concentrations for limonene and linalool hydroperoxides, added to the British baseline patch test series, to optimise detection of true allergy and minimise irritant reactions. METHODS: During 2013-2014, 4563 consecutive patients in 12 UK centres were tested to hydroperoxides of limonene in petrolatum (pet...
May 11, 2017: British Journal of Dermatology
Nicola Carslaw, Louise Fletcher, Dwayne Heard, Trevor Ingham, Hannah Walker
We report measurements of hydroxyl (OH) and hydroperoxy (HO2 ) radicals made by laser-induced fluorescence spectroscopy in a computer classroom (i) in the absence of indoor activities (ii) during desk cleaning with a limonene-containing cleaner (iii) during operation of a commercially available 'air cleaning' device. In the unmanipulated environment, the one-minute averaged OH concentration remained close to or below the limit of detection (6.5 x 10(5) molecule cm(-3) ), whilst that of HO2 was 1.3 x 10(7) molecule cm(-3) ...
May 11, 2017: Indoor Air
Xin Fang, Chen-Yi Li, Yue Yang, Meng-Ying Cui, Xiao-Ya Chen, Lei Yang
Salvia miltiorrhiza, a medicinal plant in China, has been used for thousands of years to treat coronary heart diseases. Although biosynthesis of tanshinones, a group of diterpenoids in S. miltiorrhiza, has been extensively investigated, to date we know little about the formation of monoterpenes and sesquiterpenes in this medicinal plant. Here, we report the characterization of three sesquiterpene synthases, named SmSTPS1, SmSTPS2, and SmSTPS3, which catalyzed the formation of a new compound, (-)-5-epieremophilene...
2017: Frontiers in Plant Science
Nadine Töpfer, Lisa-Maria Fuchs, Asaph Aharoni
The existence of Metabolic Gene Clusters (MGCs) in plant genomes has recently raised increased interest. Thus far, MGCs were commonly identified for pathways of specialized metabolism, mostly those associated with terpene type products. For efficient identification of novel MGCs, computational approaches are essential. Here, we present PhytoClust; a tool for the detection of candidate MGCs in plant genomes. The algorithm employs a collection of enzyme families related to plant specialized metabolism, translated into hidden Markov models, to mine given genome sequences for physically co-localized metabolic enzymes...
May 9, 2017: Nucleic Acids Research
Luis V Herrera-Marcos, José M Lou-Bonafonte, Carmen Arnal, María A Navarro, Jesús Osada
The Mediterranean diet has been proven to be highly effective in the prevention of cardiovascular diseases and cancer and in decreasing overall mortality. Nowadays, transcriptomics is gaining particular relevance due to the existence of non-coding RNAs capable of regulating many biological processes. The present work describes a systematic review of current evidence supporting the influence of the Mediterranean diet on transcriptomes of different tissues in various experimental models. While information on regulatory RNA is very limited, they seem to contribute to the effect...
May 9, 2017: Nutrients
Jian Zhang, Xinglin Li, Fuping Lu, Shanying Wang, Yunhe An, Xiaoxing Su, Xiankuan Li, Lin Ma, Guangjian Han
Periploca sepium Bunge is a traditional medicinal plant, whose root bark is important for Chinese herbal medicine. Its major bioactive compounds are C21 steroids and periplocin, a kind of cardiac glycoside, which are derived from the steroid synthesis pathway. However, research on P. sepium genome or transcriptomes and their related genes has been lacking for a long time. In this study we estimated this species nuclear genome size at 170 Mb (using flow cytometry). Then, RNA sequencing of four different tissue samples of P...
2017: Frontiers in Plant Science
Konstantinos Koudounas, Margarita Thomopoulou, Christos Michaelidis, Efstathia Zevgiti, Georgios Papakostas, Paraskevi Tserou, Gerasimos Daras, Polydefkis Hatzopoulos
Oleuropein, a terpene-derived glycosylated secoiridoid biosynthesized exclusively by members of the Oleaceae family, is involved in a two-component defense system comprising a β-glucosidase that activates oleuropein into a toxic glutaraldehyde-like structure. Oleuropein and its deglycosylated derivatives have high pharmaceutical interest. In the present study we determined that the in planta heterologous expressed OeGLU, an oleuropein-specific β-glucosidase from olive (Olea europaea) had enzymatic kinetics similar to the olive native enzyme...
May 8, 2017: Plant Physiology
Zorica S Mitić, Biljana M Nikolić, Mihailo S Ristić, Vele V Tešević, Srdjan R Bojović, Petar D Marin
Comparative analysis of terpene diversity and differentiation of relict pines Pinus heldreichii, P. nigra, and P. peuce from the central Balkans was performed at the population level. Multivariate statistical analyses showed that composition of needle terpenes reflects clear divergence among the pine species from different subgenera: P. peuce (subgenus Strobus) vs. P. nigra and P. heldreichii (subgenus Pinus). In addition, despite the described morphological similarities and the fact that P. nigra and P. heldreichii may spontaneously hybridize, our results indicated differentiation of their populations naturally growing in the same area...
May 6, 2017: Chemistry & Biodiversity
En-Hua Xia, Hai-Bin Zhang, Jun Sheng, Kui Li, Qun-Jie Zhang, Changhoon Kim, Yun Zhang, Yuan Liu, Ting Zhu, Wei Li, Hui Huang, Yan Tong, Hong Nan, Cong Shi, Chao Shi, Jian-Jun Jiang, Shu-Yan Mao, Jun-Ying Jiao, Dan Zhang, Yuan Zhao, You-Jie Zhao, Li-Ping Zhang, Yun-Long Liu, Ben-Ying Liu, Yue Yu, Sheng-Fu Shao, De-Jiang Ni, Evan E Eichler, Li-Zhi Gao
Tea is the world's oldest and most popular caffeine-containing beverage with immense economic, medicinal, and cultural importance. Here, we present the first high-quality nucleotide sequence of the repeat-rich (80.9%), 3.02-Gb genome of the cultivated tea tree Camellia sinensis. We show that an extraordinarily large genome size of tea tree is resulted from the slow, steady, and long-term amplification of a few LTR retrotransposon families. In addition to a recent whole-genome duplication event, lineage-specific expansions of genes associated with flavonoid metabolic biosynthesis were discovered, which enhance catechin production, terpene enzyme activation, and stress tolerance, important features for tea flavor and adaptation...
April 29, 2017: Molecular Plant
A Peralbo-Molina, M Calderón-Santiago, B Jurado-Gámez, M D Luque de Castro, F Priego-Capote
Smoking is a crucial factor in respiratory diseases and lung inflammation, which are the reasons for high mortality worldwide. Despite the negative impact that tobacco consumption causes on health, few metabolomics studies have compared the composition of biofluids from smoker and non-smoker individuals. Exhaled breath condensate (EBC) is one of the biofluids less employed for clinical studies despite its non-invasive sampling and the foreseeable relationship between its composition and respiratory diseases...
May 3, 2017: Scientific Reports
Mingxia Zhang, Linbo Li, Zhongwei Wu, Yanjie Wang, Yiming Zang, Guojie Liu
This study investigated the composition of volatile compounds in two pummelo cultivars, including 'Shatian' and 'Guanxi', cultivated in different regions of China with the aim of studying the effect of cultivar and cultivation condition on biosynthesis of volatile compounds in pummelo. Volatile compounds were extracted from pummelo juice using head-space microextraction and then analyzed using gas chromatography coupled with mass spectrometry. Results showed that a total of 49 volatile compounds was detected in the study, including 11 aldehydes, 7 alcohols, 3 ketones, 7 esters, 19 terpenes and 2 other volatiles...
April 29, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Marco Bonesi, Monica R Loizzo, Rosaria Acquaviva, Giuseppe A Malfa, Francesca Aiello, Rosa Tundis
BACKGROUND: Salvia species are known for their biological properties in many countries and might potentially provide novel therapeutic agents. This review provides an overview of the available literature on the anti-inflammatory and antioxidant effects of Salvia species. METHODS: Using bibliographic databases, particularly PubMed, this review aims to add new information to the list of Salvia species, including S. ceratophylla, S. chloroleuca, S. fruticosa, S. lachostachys, S...
May 2, 2017: Anti-inflammatory & Anti-allergy Agents in Medicinal Chemistry
Rakesh Kumar Chahota, Vikas Sharma, Minerva Ghani, Tilak Raj Sharma, Jai Chand Rana, Shyam Kumar Sharma
The present study explores morphological, genetic and phytochemical composition of Bunium persicum populations belonging to high altitudinal areas of Indian Himalayan region. In total, 23 morphological traits (13 quantitative and 10 qualitative traits) and 32 Random Amplified Polymorphic DNA primers were employed to infer the population structure of the species. Of the fourteen populations, five genetically diverse populations were analyzed for phytochemical diversity. Among morphological traits, inflorescence, seed and branch traits were most significant in detecting variation...
April 2017: Physiology and Molecular Biology of Plants: An International Journal of Functional Plant Biology
Anna Kårlund, Ulvi Moor, Gordon McDougall, Marko Lehtonen, Reijo O Karjalainen, Kati Hanhineva
Metabolic profiling analysis with LC-ESI-QTOF-MS was utilized to separate and identify 186 putative major metabolites demonstrating significantly different levels in 15 strawberry cultivars grown in Finland or Estonia. Principal component analysis showed close clustering of genetically related samples grown in Estonia, and hierarchical cluster analyses highlighted differences and similarities in their metabolic profiles driving separation between cultivars with specific metabolic phenotypes. Phenolic acids, flavonoids, flavan-3-ol derivatives, terpenes, and many types of glycosidically bound aroma and flavor precursors showed clear variation between strawberry cultivars...
November 2016: Food Research International
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