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Nicholas A Eddy, Pranjali Ichalkaranje
The bicyclo[4.3.0]nonane scaffold, commonly known as a hydrindane, is a common structural motif found in many terpenoid structures and one that remains a challenge for synthetic chemists to elaborate with appropriate regio- and stereo-selectivity. Over the course of the study of terpene natural products, the elaboration of the hydrindane structure has seen progress on the utilization of both old and newer methods to achieve the desired outcomes. This review seeks to serve as a general overview of these methods, and detail specific examples...
October 12, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Zahra Boghrati, Maryam Naseri, Mitra Rezaie, Ngoc Pham, Ronald J Quinn, Zahra Tayarani-Najaran, Mehrdad Iranshahi
OBJECTIVES: In food industry, the inhibition of tyrosinase is very important, because this enzyme catalyzes the oxidation of phenolic compounds found in fruits and vegetables into quinones, which contribute in undesirable color and taste of fruits and vegetables. Teucrium polium L. var. gnaphalodes (Lamiaceae), a wild-growing flowering plant that has many applications in food preparations and traditional medicine. In Persian language, this medicinal herb is called Kalpoureh. MATERIALS AND METHODS: 1D- and 2D-NMR experiments were used to determine the chemical structures of the isolated compounds...
August 2016: Iranian Journal of Basic Medical Sciences
Sushanto Gouda, Gitishree Das, Sandeep K Sen, Han-Seung Shin, Jayanta Kumar Patra
Endophytes are an endosymbiotic group of microorganisms that colonize in plants and microbes that can be readily isolated from any microbial or plant growth medium. They act as reservoirs of novel bioactive secondary metabolites, such as alkaloids, phenolic acids, quinones, steroids, saponins, tannins, and terpenoids that serve as a potential candidate for antimicrobial, anti-insect, anticancer and many more properties. While plant sources are being extensively explored for new chemical entities for therapeutic purposes, endophytic microbes also constitute an important source for drug discovery...
2016: Frontiers in Microbiology
Qinghuan Xu, Lin Yang, Wangting Yang, Yan Bai, Ping Hou, Jingxian Zhao, Lv Zhou, Zhaojiang Zuo
Eutrophication promotes massive growth of cyanobacteria and algal blooms, which can poison other algae and reduce biodiversity. To investigate the differences in multiple nitrogen (N) sources in eutrophicated water on the emission of volatile organic compounds (VOCs) from cyanobacteria, and their toxic effects on other algal growth, we analyzed VOCs emitted from Microcystis flos-aquae with different types and concentrations of nitrogen, and determined the effects under Normal-N and Non-N conditions on Chlorella vulgaris...
October 11, 2016: Ecotoxicology and Environmental Safety
Harsha Lad, Deepak Bhatnagar
The present study was aimed to determine the therapeutic effects of Swertia chirayita leaves against oxidative and inflammatory injuries in Freund's complete adjuvant (FCA) induced arthritic rats. The extract was evaluated for its phytoconstituents and various invitro antioxidant properties followed by its in vivo effects. The hydroethanolic extract of S. chirayita leaves (SCE) was orally administered (200 mg/kg body weight, per day, p.o.) and the effect on the liver lipid peroxidation (LPO), antioxidant status, protein carbonyl formation along with the histopathology of liver were evaluated after induction of adjuvant arthritis...
October 14, 2016: Inflammopharmacology
Klaus Speck, Raphael Wildermuth, Thomas Magauer
The cationic cyclization of polyenes constitutes a powerful and elegant transformation, which has been utilized by nature's biosynthetic machinery for the construction of complex polycyclic terpenoids. Previous studies by chemists to mimic this cyclization in the laboratory were limited to different modes of activation using biosynthetic-like precursors, which accommodate only simple methyl-derived substituents. Here we describe the development of an unprecedented and highly efficient polyene cyclization of an aryl enol ether containing substrate...
October 12, 2016: Angewandte Chemie
Cosima Damiana Calvano, Giovanni Ventura, Massimo Trotta, Giuliana Bianco, Tommaso R I Cataldi, Francesco Palmisano
Bacteriochlorophyll a (BChl a), a photosynthetic pigment performing the same functions of chlorophylls in plants, features a bacteriochlorin macrocycle ring (18 π electrons) with two reduced pyrrole rings along with a hydrophobic terpenoid side chain (i.e., the phytol residue). Chlorophylls analysis by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) is not so straightforward since pheophytinization (i.e., release of the central metal ion) and cleavage of the phytol-ester linkage are invariably observed by employing protonating matrices such as 2,5-dihydroxybenzoic acid, sinapinic acid, and α-cyano-4-hydroxycinnamic acid...
October 11, 2016: Journal of the American Society for Mass Spectrometry
Sang-Yong Kim, Hisako Nagashima, Naonobu Tanaka, Yoshiki Kashiwada, Jun'ichi Kobayashi, Mareshige Kojoma
Two novel C25 terpenoids with a 6/5/5/5/5/3 hexacyclic skeleton including one γ-lactone ring and two tetrahydrofuran rings, hitorins A (1) and B (2), were isolated from the aerial parts of Chloranthus japonicus. The structures of 1 and 2 were elucidated on the basis of spectroscopic analyses as well as TDDFT ECD calculations. Hitorins A (1) and B (2) might be biogenetically derived from eudesmane sesquiterpene and thujane monoterpene.
October 10, 2016: Organic Letters
Lorenzo Di Cesare Mannelli, Laura Micheli, Mario Maresca, Giancarlo Cravotto, Maria Bellumori, Marzia Innocenti, Nadia Mulinacci, Carla Ghelardini
Traditional uses and current results highlight the neuroprotective properties of Rosmarinus officinalis L. The compelling need for novel strategies able to relieve neuropathic pain encouraged us to analyze different rosemary leaf extracts in rats following chronic constriction injury (CCI) of sciatic nerve. Ethanol, acetone, and the innovative ultrasound-hexane extractive methods were used to obtain: EE, AE, and for hexane extracts UREprel and URE. Extracts were characterized in terms of typical constituents and repeatedly administered to CCI-rats (13-days treatment, from the day of surgery)...
October 7, 2016: Scientific Reports
Fu-Zhuo Li, Shuang Li, Peng-Peng Zhang, Zhi-Hui Huang, Wei-Bin Zhang, Jianxian Gong, Zhen Yang
Ozonolysis of aromatic abietane (+)-carnosic acid (4) is used to create an important intermediate in an enantiomerically pure form, resulting in a simple, concise, readily scalable, and asymmetric synthesis of (-)-antrocin (1). This strategy not only provides an efficient approach to (-)-antrocin (1) synthesis but can also be readily adopted for the syntheses of optically pure (+)-asperolide C (2) and (-)-trans-ozic acid (3) from the naturally abundant aromatic abietanes (+)-podocarpic acid (5) and (+)-dehydroabietic acid (6)...
October 13, 2016: Chemical Communications: Chem Comm
Heidi R Schoen, Brent M Peyton, W Berk Knighton
A novel analytical system was developed to rapidly and accurately quantify total volatile organic compound (VOC) production from microbial reactor systems using a platinum catalyst and a sensitive CO2 detector. This system allows nearly instantaneous determination of total VOC production by utilizing a platinum catalyst to completely and quantitatively oxidize headspace VOCs to CO2 in coordination with a CO2 detector. Measurement of respiratory CO2 by bypassing the catalyst allowed the total VOC content to be determined from the difference in the two signals...
December 2016: AMB Express
Eugenio Alcalde, Paul David Fraser
The filamentous fungus Phycomyces blakesleeanus provides a renewable biosource of industrial high value compounds such as carotenes, other isoprenoids (ubiquinone and sterols), organic acids and fatty acids. Several Phycomyces mutants involved in the formation of β-carotene are available. For example the carA mutants have a leaky mutation in the phytoene synthase and produce significantly lower amount of carotenes, while the carB and carR mutants produce phytoene and lycopene respectively, due to a null mutation in the genes encoding the phytoene dehydrogenase and lycopene cyclase respectively...
October 4, 2016: Microbiology
B Zhou, S-Z Liu, M-J Li, Z-H Chen, P Wang, D Cheng
Chimonanthus nitens Oliv. is a commonly used traditional Chinese medicine. Terpenoids, flavonoids, and coumarins are usually considered its main bioactive ingredients. Thus, qualitative and quantitative analyses of these compounds are crucial in quality control studies of Chimonanthus nitens. In this study, five compounds were identified by double-development thin layer chromatography (TLC) and the content of four compounds was determined by high performance liquid chromatography; the detection wavelength was set to 344 nm and the column temperature was 40°C...
August 29, 2016: Genetics and Molecular Research: GMR
Michael B Reardon, Muyun Xu, Qingzhe Tan, Peter G Baumgartel, Danielle J Augur, Shuanghong Huo, Charles E Jakobsche
Derivatives of geraniol are versatile synthetic intermediates that are useful for synthesizing a variety of terpenoid natural products; however, the results presented herein show that subtle differences in the structures of functionalized geranyl chlorides can significantly impact their abilities to function as effective electrophiles in synthetic reactions. A series of focused kinetics experiments identify specific structure-activity relationships that illustrate the importance not only of steric bulk, but also of electronic effects from distant regions of the molecules that contribute to their overall level of reactivity...
October 5, 2016: Journal of Organic Chemistry
Akansha Pandey, Vishakha Swarnkar, Tushar Pandey, Piush Srivastava, Sanjeev Kanojiya, Dipak Kumar Mishra, Vineeta Tripathi
Calotropis procera is a medicinal plant of immense importance due to its pharmaceutical active components, especially cardiac glycosides (CG). As genomic resources for this plant are limited, the genes involved in CG biosynthetic pathway remain largely unknown till date. Our study on stage and tissue specific metabolite accumulation showed that CG's were maximally accumulated in stems of 3 month old seedlings. De novo transcriptome sequencing of same was done using high throughput Illumina HiSeq platform generating 44074 unigenes with average mean length of 1785 base pair...
October 5, 2016: Scientific Reports
Fei Chen, Cheng-Gang Ren, Tong Zhou, Yu-Jia Wei, Chuan-Chao Dai
Endophytes and plants can establish specific long-term symbiosis through the accumulation of secondary metabolites. Previous studies have shown that the endophytic fungus Gilmaniella sp. AL12 can stimulate Atractylodes lancea to produce volatile oils. The purpose of this report is to investigate key factors involved in the stimulation of A. lancea by AL12 and reveal the mechanism. We identified the active component from AL12 as an extracellular mannan with a polymerization degree of 26-42. Differential membrane proteomics of A...
October 5, 2016: Scientific Reports
V Kishore, Nagend Nagendra Sastry Yarla, Anupam Bishayee, Swathi Putta, Ramarao Malla, Nageswara Rao Reddy Neelapu, Yallappa Shiralgi, Gurumurthy Hegde, Bhadrapura Lakkappa Dhananjaya
Andrographis paniculata (A. paniculata), a medicinal plant used in the traditional Indian and Chinese medicinal systems for its various beneficial properties owing to the presence of a diterpene lactone called 'andrographolide'. Several biological activities like anti-inflammatory, antitumour, anti-hyperglycaemic, anti-fertility, antiviral, cardio protective and hepatoprotective properties are attributed to andrographolide and its analogs. The studies have shown that not only this diterpene lactone (andrographolide), and other related terpenoid analogs from A...
September 27, 2016: Current Topics in Medicinal Chemistry
Jan Mertens, Alex Van Moerkercke, Robin Vanden Bossche, Jacob Pollier, Alain Goossens
Plants produce many bioactive, specialized metabolites to defend themselves when facing various stress situations. Their biosynthesis is directed by a tightly controlled regulatory circuit that is elicited by phytohormones such as jasmonate (JA). The basic helix-loop-helix (bHLH) transcription factors (TFs) bHLH iridoid synthesis 1 (BIS1) and Triterpene Saponin Activating Regulator (TSAR) 1 and 2, from Catharanthus roseus and Medicago truncatula, respectively, all belong to clade IVa of the bHLH protein family and activate distinct terpenoid pathways, thereby mediating monoterpenoid indole alkaloid (MIA) and triterpene saponin (TS) accumulation, respectively, in these two species...
October 1, 2016: Plant & Cell Physiology
Hanane Bouanou, Juan A Gil, Ramón Alvarez-Manzaneda, Rachid Chahboun, Enrique Alvarez-Manzaneda
Treatment of (-)-sclareol and related compounds with lead tetraacetate affords tetracyclic compounds bearing a 2,8-dioxabicyclo[5.2.0]nonane moiety with complete regio- and stereoselectivity. This process, which is also applicable to 1,5-diols with a similar substitution pattern, facilitates the development of efficient syntheses toward oxepane terpenoids, such as aplysistatin derivatives.
October 7, 2016: Journal of Organic Chemistry
Dineshkumar Kandasamy, Jonathan Gershenzon, Almuth Hammerbacher
Conifer bark beetles attack and kill mature spruce and pine trees, especially during hot and dry conditions. These beetles are closely associated with ophiostomatoid fungi of the Ascomycetes, including the genera Ophiostoma, Grosmannia, and Endoconidiophora, which enhance beetle success by improving nutrition and modifying their substrate, but also have negative impacts on beetles by attracting predators and parasites. A survey of the literature and our own data revealed that ophiostomatoid fungi emit a variety of volatile organic compounds under laboratory conditions including fusel alcohols, terpenoids, aromatic compounds, and aliphatic alcohols...
September 29, 2016: Journal of Chemical Ecology
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