Cyanobacteria—From the Oceans to the Potential Biotechnological and Biomedical Applications

Cyanobacteria are photosynthetic prokaryotic organisms which represent a significantsource of novel, bioactive, secondary metabolites, and they are also considered an abundant source ofbioactive compounds/drugs, such as dolastatin, cryptophycin 1, curacin toyocamycin, phytoalexin,cyanovirin-N and phycocyanin. Some of these compounds have displayed promising results insuccessful Phase I, II, III and IV clinical trials. Additionally, the cyanobacterial compounds applied tomedical research have demonstrated an exciting future with great potential to be developed into newmedicines. Most of these compounds have exhibited strong pharmacological activities, includingneurotoxicity, cytotoxicity and antiviral activity against HCMV, HSV-1, HHV-6 and HIV-1, so thesemetabolites could be promising candidates for COVID-19 treatment. Therefore, the effective large-scale production of natural marine products through synthesis is important for resolving the existingissues associated with chemical isolation, including small yields, and may be necessary to betterinvestigate their biological activities. Herein, we highlight the total synthesized and stereochemicaldeterminations of the cyanobacterial bioactive compounds. Furthermore, this review primarilyfocuses on the biotechnological applications of cyanobacteria, including applications as cosmetics,food supplements, and the nanobiotechnological applications of cyanobacterial bioactive compoundsin potential medicinal applications for various human diseases are discussed.Stockholm UniversityPeer Reviewe

An overview of NMR-based metabolomics to identify secondary plant compounds involved in host plant resistance

Secondary metabolites provide a potential source for the generation of host plant resistance and development of biopesticides. This is especially important in view of the rapid and vast spread of agricultural and horticultural pests worldwide. Multiple pests control tactics in the framework of an integrated pest management (IPM) programme are necessary. One important strategy of IPM is the use of chemical host plant resistance. Up to now the study of chemical host plant resistance has, for technical reasons, been restricted to the identification of single compounds applying specific chemical analyses adapted to the compound in question. In biological processes however, usually more than one compound is involved. Metabolomics allows the simultaneous detection of a wide range of compounds, providing an immediate image of the metabolome of a plant. One of the most universally used metabolomic approaches comprises nuclear magnetic resonance spectroscopy (NMR). It has been NMR which has been applied as a proof of principle to show that metabolomics can constitute a major advancement in the study of host plant resistance. Here we give an overview on the application of NMR to identify candidate compounds for host plant resistance. We focus on host plant resistance to western flower thrips (Frankliniella occidentalis) which has been used as a model for different plant species

Root-emitted volatile organic compounds: can they mediate belowground plant-plant interactions?

peer reviewedBackground Aboveground, plants release volatile organic compounds (VOCs) that act as chemical signals between neighbouring plants. It is now well documented that VOCs emitted by the roots in the plant rhizosphere also play important ecological roles in the soil ecosystem, notably in plant defence because they are involved in interactions between plants, phytophagous pests and organisms of the third trophic level. The roles played by root-emitted VOCs in between- and within-plant signalling, however, are still poorly documented in the scientific literature. Scope Given that (1) plants release volatile cues mediating plant-plant interactions aboveground, (2) roots can detect the chemical signals originating from their neighbours, and (3) roots release VOCs involved in biotic interactions belowground, the aim of this paper is to discuss the roles of VOCs in between- and within-plant signalling belowground. We also highlight the technical challenges associated with the analysis of root-emitted VOCs and the design of experiments targeting volatile-mediated root-root interactions. Conclusions We conclude that root-root interactions mediated by volatile cues deserve more research attention and that both the analytical tools and methods developed to study the ecological roles played by VOCs in interplant signalling aboveground can be adapted to focus on the roles played by root-emitted VOCs in between- and within-plant signalling

Towards eco-friendly crop protection: natural deep eutectic solvents and defensive secondary metabolites

Plant science

Chemical classification of the essential oils of the Iranian salvia species in comparison to their botanical taxonomy

The essential oils of eight Salvia species collected from different localities in Iran were analyzed by gas chromatography/mass spectrometry (GC/MS). The analytical results were compared with thosepreviously published for related Iranian sage species in order to identify chemical markers for thesespecies.Salvia eremophila,S. hypoleuca, andS. reuterianaare endemic, whileS. atropatana,S.chloroleuca,S. santolinifolia,S. aegyptiaca, andS. macrosiphonalso grow wild in neighboring countries.We categorized the IranianSalviaspecies into four main chemotypes according to their essential-oilconstituents: those which are dominated by1) monoterpenes,2) mono- and sesquiterpenes, or3)sesquiterpenes as the major constituents, and4) those containing low-molecular-weight acids, aldehydes,and esters, and green-leaf volatiles (GLVs). Likely due to the chemical diversity of differentSalviachemotypes, this categorization was supported by principal component analysis (PCA) for the groupsampled here, but not for the values reported in the literature. We identified the following chemicalmarkers:a-pinene,b-pinene, 1,8-cineol, linalool, and borneol in monoterpene-rich species,orb-caryophyllene, germacrene D, bicyclogermacrene, spathulenol, and caryophyllene oxide in sesquiter-pene-rich species. Among these,a-pinene,b-caryophyllene, and germacrene D are the most common andabundant in theSalviaspecies investigated. In accordance with their close biological taxonomy, thechemical similarity of the essential oils ofS. santolinifoliaandS. eremophilais so high that we mayconsider them chemically identical