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Molecules (Basel, Switzerland) Jan 2021By the end of the twentieth century, the interest in natural compounds as probable sources of drugs has declined and was replaced by other strategies such as molecular... (Review)
Review
By the end of the twentieth century, the interest in natural compounds as probable sources of drugs has declined and was replaced by other strategies such as molecular target-based drug discovery. However, in the recent times, natural compounds regained their position as extremely important source drug leads. Indole-containing compounds are under clinical use which includes vinblastine and vincristine (anticancer), atevirdine (anti-HIV), yohimbine (erectile dysfunction), reserpine (antihypertension), ajmalicine (vascular disorders), ajmaline (anti-arrhythmic), vincamine (vasodilator), etc. Monoterpene Indole Alkaloids (MIAs) deserve the curiosity and attention of researchers due to their chemical diversity and biological activities. These compounds were considered as an impending source of drug-lead. In this review 444 compounds, were identified from six genera belonging to the family Apocynaceae, will be discussed. These genera (, , , , and and ) consist of 400 members and represent 20% of Apocynaceae species. Only 30 (7.5%) species were investigated, whereas the rest are promising to be investigated. Eleven bioactivities, including antibacterial, antifungal, anti-inflammatory and immunosuppressant activities, were reported. Whereas cytotoxic effect represents 47% of the reported activities. Convincingly, the genera selected in this review are a wealthy source for future anticancer drug lead.
Topics: Apocynaceae; Indole Alkaloids; Molecular Structure; Monoterpenes; Plant Extracts
PubMed: 33477682
DOI: 10.3390/molecules26020488 -
Archives of Biochemistry and Biophysics Feb 2024Rhodococcus globerulus (R. globerulus) was isolated from the soil beneath a Eucalypt tree. Metabolic growth studies revealed that R. globerulus was capable of living on...
Rhodococcus globerulus (R. globerulus) was isolated from the soil beneath a Eucalypt tree. Metabolic growth studies revealed that R. globerulus was capable of living on certain monoterpenes, including 1,8-cineole and p-cymene, as sole sources of carbon and energy. Multiple P450 genes were identified in the R. globerulus genome that shared homology to known bacterial, monoterpene hydroxylating P450s. To date, two of these P450s have been expressed and characterised as 1,8-cineole (CYP176A1) and p-cymene (CYP108N12) monooxygenases that are believed to initiate the biodegradation of these terpenes. In this work, another putative P450 gene (CYP108N14) was identified in R. globerulus genome. Given its amino acid sequence identity to other monoterpene hydroxylating P450s it was hypothesised to catalyse monoterpene hydroxylation. These include CYP108A1 from Pseudomonas sp. (47 % identity, 68 % similarity) which hydroxylates α-terpineol, and CYP108N12 also from R. globerulus (62 % identity, 77 % similarity). Also present in the operon containing CYP108N14 were putative ferredoxin and ferredoxin reductase genes, suggesting a typical Class I P450 system. CYP108N14 was successfully over-expressed heterologously and purified, resulting in a good yield of CYP108N14 holoprotein. However, neither the ferredoxin nor ferredoxin reductase could be produced heterologously. Binding studies with CYP108N14 revealed a preference for the monoterpenes p-cymene, (R)-limonene, (S)-limonene, (S)-α-terpineol and (S)-4-terpineol. An active catalytic system was reconstituted with the non-native redox partners cymredoxin (from the CYP108N12 system) and putidaredoxin reductase (from the CYP101A1 system). CYP108N14 when supported by these redox partners was able to catalyse the hydroxylation of the five aforementioned substrates selectively at the methyl benzylic/allylic positions.
Topics: Monoterpenes; Eucalyptol; Cytochrome P-450 Enzyme System; Ferredoxins; Limonene; Cyclohexane Monoterpenes; Cymenes; Rhodococcus
PubMed: 38072297
DOI: 10.1016/j.abb.2023.109852 -
Mechanisms of Ageing and Development Mar 2020Senescent cells have been suspected, because of their secretory phenotype (SASP or Senescence Associated Secretory Profile), to contribute to the extension of the... (Review)
Review
Senescent cells have been suspected, because of their secretory phenotype (SASP or Senescence Associated Secretory Profile), to contribute to the extension of the chronic inflammatory condition leading to unhealthy aging processes. AISA (Anti-Inflammatory Senescence Actives) monoterpens have been characterized as possessing anti-inflammatory capacities in young cells submitted to pro-inflammatory cytokine stimulation. They have also been demonstrated to have the ability to act on senescent cells, reversing their characteristic pro-inflammatory phenotype. This is due to the fact that AISA act on the cytoskeleton scaffold of cells where actin polymerization induces the expression of adhesion molecules, fueling the infernal inflammatory loop. In comparison to other isoprenoid actives in degenerative diseases, the AISA monoterpene adds a mood-modulating capacity inducing the vagus nerve tone and its potent anti-inflammatory role.
Topics: Aging; Cellular Senescence; Humans; Inflammation; Monoterpenes
PubMed: 31904411
DOI: 10.1016/j.mad.2019.111206 -
Molecules (Basel, Switzerland) Dec 2020Monoterpenes are plant secondary metabolites, widely used in industrial processes as precursors of important aroma compounds, such as vanillin and (-)-menthol. However,... (Review)
Review
Monoterpenes are plant secondary metabolites, widely used in industrial processes as precursors of important aroma compounds, such as vanillin and (-)-menthol. However, the physicochemical properties of monoterpenes make difficult their conventional conversion into value-added aromas. Biocatalysis, either by using whole cells or enzymes, may overcome such drawbacks in terms of purity of the final product, ecological and economic constraints of the current catalysis processes or extraction from plant material. In particular, the ability of oxidative enzymes (e.g., oxygenases) to modify the monoterpene backbone, with high regio- and stereo-selectivity, is attractive for the production of "natural" aromas for the flavor and fragrances industries. We review the research efforts carried out in the molecular analysis of bacterial monoterpene catabolic pathways and biochemical characterization of the respective key oxidative enzymes, with particular focus on the most relevant precursors, β-pinene, limonene and β-myrcene. The presented overview of the current state of art demonstrates that the specialized enzymatic repertoires of monoterpene-catabolizing bacteria are expanding the toolbox towards the tailored and sustainable biotechnological production of values-added aroma compounds (e.g., isonovalal, α-terpineol, and carvone isomers) whose implementation must be supported by the current advances in systems biology and metabolic engineering approaches.
Topics: Acyclic Monoterpenes; Animals; Bacteria; Bicyclic Monoterpenes; Biotechnology; Humans; Limonene; Monoterpenes; Odorants
PubMed: 33379215
DOI: 10.3390/molecules26010091 -
Current Opinion in Chemical Biology Oct 2016Synthetic biology is opening up new opportunities for the sustainable and efficient production of valuable chemicals in engineered microbial factories. Here we review... (Review)
Review
Synthetic biology is opening up new opportunities for the sustainable and efficient production of valuable chemicals in engineered microbial factories. Here we review the application of synthetic biology approaches to the engineering of monoterpene/monoterpenoid production, highlighting the discovery of novel catalytic building blocks, their accelerated assembly into functional pathways, general strategies for product diversification, and new methods for the optimization of productivity to economically viable levels. Together, these emerging tools allow the rapid creation of microbial production systems for a wide range of monoterpenes and their derivatives for a diversity of industrial applications.
Topics: Monoterpenes; Synthetic Biology
PubMed: 27315341
DOI: 10.1016/j.cbpa.2016.06.002 -
PloS One 2022The essential oil from Rosmarinus officinalis L., a composite mixture of plant-derived secondary metabolites, exhibits antifungal activity against virulent candidal...
The essential oil from Rosmarinus officinalis L., a composite mixture of plant-derived secondary metabolites, exhibits antifungal activity against virulent candidal species. Here we report the impact of rosemary oil and two of its components, the monoterpene α-pinene and the monoterpenoid 1,8-cineole, against Candida albicans, which induce ROS-dependent cell death at high concentrations and inhibit hyphal morphogenesis and biofilm formation at lower concentrations. The minimum inhibitory concentrations (100% inhibition) for both rosemary oil and 1,8-cineole were 4500 μg/ml and 3125 μg/ml for α-pinene, with the two components exhibiting partial synergy (FICI = 0.55 ± 0.07). At MIC and 1/2 MIC, rosemary oil and its components induced a generalized cell wall stress response, causing damage to cellular and organelle membranes, along with elevated chitin production and increased cell surface adhesion and elasticity, leading to complete vacuolar segregation, mitochondrial depolarization, elevated reactive oxygen species, microtubule dysfunction, and cell cycle arrest mainly at the G1/S phase, consequently triggering cell death. Interestingly, the same oils at lower fractional MIC (1/8-1/4) inhibited virulence traits, including reduction of mycelium (up to 2-fold) and biofilm (up to 4-fold) formation, through a ROS-independent mechanism.
Topics: Rosmarinus; Eucalyptol; Candida albicans; Reactive Oxygen Species; Virulence; Oils, Volatile; Microbial Sensitivity Tests; Antifungal Agents; Monoterpenes
PubMed: 36383525
DOI: 10.1371/journal.pone.0277097 -
Journal of Chemical Ecology Sep 2019The koala is a specialist feeder with a diet consisting almost exclusively of potentially toxic eucalypt leaves. Monoterpenes, an abundant class of plant secondary...
The koala is a specialist feeder with a diet consisting almost exclusively of potentially toxic eucalypt leaves. Monoterpenes, an abundant class of plant secondary metabolites in eucalypts, are highly lipophilic. Chronic absorption and systemic exposure can be anticipated for the koala, causing health effects in various ways when consumed in high amounts, but particularly causing alterations in immune function in this species. Therefore, careful leaf selection, efficient detoxification pathways, and other specialist adaptations are required to protect animals from acute intoxication. This is the first paper providing insight into the systemic exposure of koalas to these compounds. Profiles of six selected major monoterpenes were investigated in the ingesta of deceased koalas from four different regions of NSW and South-East Queensland. Concentrations of the same compounds were measured in lymphoid tissues of deceased koalas and in the blood of live koalas from other regions of NSW. Analytical methods included liquid extraction and solid-phase micro-extraction, followed by gas-chromatography/ mass-spectrometry. Concentrations in the ingesta of individual animals vary remarkably, though the average proportions of individual monoterpenes in the ingesta of animals from the four different regions are highly comparable. Blood concentrations of the selected monoterpenes also varied considerably. The highest blood concentrations were found for 1,8-cineole, up to 971 ng/ml. There was similarity between circulating monoterpene profiles and ingesta profiles. Based on the observed lack of similarity between blood and lymph tissue concentrations, individual monoterpenes either exhibit different affinities for lymphatic tissue compared to blood or their accumulation in blood and lymph tissue differs temporally. In general, blood monoterpene concentrations found in koalas were low compared to those reported in other marsupial eucalypt feeders, but significant concentrations of monoterpenes were detected in all samples analysed. This data on blood and lymphatic tissue monoterpene concentrations builds the fundamental groundwork for future research into the effects of dietary monoterpenes on various biological processes of specialist herbivores and into the significance of these animals' metabolic and behavioural strategies for coping with these compounds. We have shown that the systemic exposure of koalas to potentially anti-inflammatory eucalypt monoterpenes is continuous, and we provide data on physiological concentrations which will allow realistic future studies of the effects of monoterpenes on immune cell function.
Topics: Animals; Australia; Eucalyptus; Feeding Behavior; Monoterpenes; Phascolarctidae; Plant Leaves
PubMed: 31422515
DOI: 10.1007/s10886-019-01097-x -
Food Research International (Ottawa,... Dec 2023Low temperature is the commonly used technique for maintaining the quality of table grapes during postharvest storage. However, this technique could strongly affect the...
Low temperature is the commonly used technique for maintaining the quality of table grapes during postharvest storage. However, this technique could strongly affect the aromatic flavor of fruit. Monoterpenes are the key compounds contributing to the Muscat aromas of grapes. The detailed information and molecular mechanisms underlying the changes in monoterpenes during postharvest low temperature storage have not been thoroughly characterized. In this study, the effects of low temperature storage on the free and bound monoterpene profiles in four cultivars of table grape were determined at both the transcriptomic and metabolomic levels. A total of 27 compounds in both free and bound forms were identified in the four cultivars and showed quantitative differences between the cultivars. Hierarchical cluster and principal component analysis indicated that the free and bound monoterpene profiles were remarkably affected by the low temperature storage. The monoterpenes in the same biosynthesis pathway were clustered together and showed similar evolution trends during low temperature storage. And the content of most of free monoterpenes underwent a rapid decline during low-temperature storage at a certain stage, but the time was different in 4 grape cultivars. Transcriptomic analysis revealed that the expression of DXS, HDR, GPPS and TPS genes involved in the monoterpene synthesis pathway were consistent with the changes in the accumulation of monoterpene compounds. While the expression of HMGS, HMGR genes in MVA pathway and branch genes GGPPS and FPPS were negatively correlated with the accumulation of monoterpenes. The findings provide new insights into the underlying mechanisms of the berry aroma flavor change during low temperature storage.
Topics: Monoterpenes; Vitis; Transcriptome; Temperature; Odorants
PubMed: 37986463
DOI: 10.1016/j.foodres.2023.113601 -
The Plant Journal : For Cell and... Apr 2023Terrestrial plants emit volatiles into the atmosphere to attract both pollinators and the enemies of herbivores, for defense. Phalaenopsis bellina is a scented orchid...
Terrestrial plants emit volatiles into the atmosphere to attract both pollinators and the enemies of herbivores, for defense. Phalaenopsis bellina is a scented orchid species in which the main scent components are monoterpenes, including linalool and geraniol, and their derivatives. Here, we investigated whether ABC transporters are involved in floral scent emission. We carried out whole-genome identification of ABC transporter-related genes using four floral transcriptomics libraries of P. bellina. We identified 86 ABC subfamily G genes related to terpenoid transport. After comparing the gene expression patterns of P. bellina with that of Phalaenopsis aphrodite subsp. formosana, a scentless species, followed by gene-to-gene correlation analysis, PbABCG1 and PbABCG2 were selected. The temporal expression of both PbABCG1 and PbABCG2 was highly correlated with that of the key enzyme PbGDPS and the major transcription factor PbbHLH4 in monoterpene biosynthesis, with optimal expression on day 5 post-anthesis. Spatial gene expression analysis showed that PbABCG1 was highly expressed in sepals, whereas PbABCG2 was expressed in the lip. Subcellular localization with a GFP fusion protein revealed that both PbABCG1 and PbABCG2 are cytoplasmic membrane proteins. Co-downregulation of PbABCG1 and PbABCG2 using both double-strand RNA interference and tobacco rattle virus-based gene silencing led to a significant decrease in monoterpene emission, accompanied by an increase in the internal monoterpene pools. Furthermore, ectopic expression of PbABCG1 and PbABCG2 in an ABC16 mutant yeast strain rescued its tolerance to geraniol. Altogether, our results indicate that PbABCG1 and PbABCG2 play substantial roles in monoterpene transport/emission in P. bellina floral scent.
Topics: Monoterpenes; Plant Proteins; Flowers; Orchidaceae
PubMed: 36738107
DOI: 10.1111/tpj.16133 -
Natural Product Research Feb 2017As a result of our efforts to identify bioactive agents from marine algae, we have isolated and identified one new halogenated monoterpene 1...
As a result of our efforts to identify bioactive agents from marine algae, we have isolated and identified one new halogenated monoterpene 1 [(-)-(5E,7Z)-348-trichloro-7-dichloromethyl-3-methyl-157-octatriene] in addition to three known compounds (2, 3 and 4) from the red alga Plocamium cartilagineum collected by hand from the eastern coast of South Africa. Compound 1 was found to be active as a cytotoxic agent in human lung cancer (NCI-H460) and mouse neuro-2a cell lines (IC 4 μg/mL). Two of these compounds (3 and 4) were found to have cytotoxic activity in other cell line assays, especially against human leukaemia and human colon cancers (IC 1.3 μg/mL). None of these metabolites were active as sodium channel blockers or activators. All structures were determined by spectroscopic methods (UV, IR, LRMS, HRMS, 1D NMR and 2D NMR). 1D and 2D NOE experiments were carried out on these compounds to confirm the geometry of the double bonds.
Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Colonic Neoplasms; Halogenation; Humans; Leukemia; Lung Neoplasms; Magnetic Resonance Spectroscopy; Mice; Molecular Structure; Monoterpenes; Plocamium; Spectrum Analysis
PubMed: 27627578
DOI: 10.1080/14786419.2016.1230115