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The mangrove ecosystem is being intensively studied with the hope of discovering new chemical entities with biomedical potentials. A number of biologically active compounds with varying degrees of action such as anticancer, antiulcer, antioxidant, antidiabetic and antimicrobial properties have been isolated from mangroves. Totally 81 mangrove species have been reported worldwide, of which 46 species are reported to occur in India. Among these, around 36 mangrove species are used in traditional medicine. Approximately 249 bioactive compounds have been isolated from 18 species, and the remaining species are yet to be screened. Biologically active compounds such as limonoids, terpenoids, alkaloids, glycosides, steroids, flavonoids, esters, quinones, phenols, acids, aliphatic alcohol, amides, lactones, aliphatic ketones, and benzodioxols have been derived from the leaves, stems, barks, fruits, and seeds of Indian mangrove plants. This review examines the current trends in the screening and biological activity of metabolites from the Indian mangroves. This comprehensive review in turn can serve as a potential resource for future drug development endeavours.

Abstract: Recent advancements in medicinal research have identified several antiviral and anticancer terpenoids that are usually deployed as a source of flavor, fragrances and pharmaceuticals. Under the current COVID-19 pandemic conditions, natural therapeutics with the least side effects are the need of the hour to save the patients, especially, which are pre-affected with other medical complications. Although plants are the major sources of terpenoids; however, for the environmental concerns, the global interest has shifted to the biocatalytic production of molecules from microbial sources. The gram-positive bacterium Bacillus subtilis is a suitable host in this regard due to its GRAS (generally regarded as safe) status, ease in genetic manipulations and wide industrial acceptability. The B. subtilis synthesizes its terpenoid molecules from 1-deoxy-d-xylulose-5-phosphate (DXP) pathway, a common route in almost all microbial strains. Here, we summarize the computational and synthetic biology approaches to improve the production of terpenoid-based therapeutics from B. subtilis by utilizing DXP pathway. We focus on the in-silico approaches for screening the functionally improved enzyme-variants of the two crucial enzymes namely, the DXP synthase (DXS) and Farnesyl Pyrophosphate Synthase (FPPS). The approaches for engineering the active sites are subsequently explained. It will be helpful to construct the functionally improved enzymes for the high-yield production of terpenoid-based anticancer and antiviral metabolites, which would help to reduce the cost and improve the availability of such therapeutics for the humankind.

Moroccan medicinal plants exhibit several pharmacological properties such as antimicrobial, anticancer, antidiabetic, analgesic, and anti-inflammatory effects, which are related to the presence of numerous bioactive compounds, including phenolic acids, flavonoids, and terpenoids. In the present review, we systematically evaluate previously published reports on the anti-inflammatory and analgesic effects of Moroccan medicinal plants. The in vitro investigations revealed that Moroccan medicinal plants inhibit several enzymes related to inflammatory processes, whereas in vivo studies noted significant anti-inflammatory and analgesic effects as demonstrated using different experimental models. Various bioactive compounds exhibiting in vitro and in vivo anti-inflammatory and analgesic effects, with diverse mechanisms of action, have been identified. Some plants and their bioactive compounds revealed specific secondary metabolites that possess important anti-inflammatory effects in clinical investigations. Our review proposes the potential applications of Moroccan medicinal plants as sources of anti-inflammatory and analgesic agents.

Coronaviruses have caused worldwide outbreaks in different periods. SARS (severe acute respiratory syndrome) was the first emerged virus from this family, followed by MERS (Middle East respiratory syndrome) and SARS-CoV-2 (2019-nCoV or COVID 19), which is newly emerged. Many studies have been conducted on the application of chemical and natural drugs for treating these coronaviruses and they are mostly focused on inhibiting the proteases of viruses or blocking their protein receptors through binding to amino acid residues. Among many substances which are introduced to have an inhibitory effect against coronaviruses through the mentioned pathways, natural components are of specific interest. Secondary and primary metabolites from plants, are considered as potential drugs to have an inhibitory effect on coronaviruses. IC50 value (the concentration in which there is 50% loss in enzyme activity), molecular docking score and binding energy are parameters to understand the ability of metabolites to inhibit the specific virus. In this study we reviewed 154 papers on the effect of plant metabolites on different coronaviruses and data of their IC50 values, molecular docking scores and inhibition percentages are collected in tables. Secondary plant metabolites such as polyphenol, alkaloids, terpenoids, organosulfur compounds, saponins and saikosaponins, lectins, essential oil, and nicotianamine, and primary metabolites such as vitamins are included in this study.

The genus Fuchsia is generally used in herbal preparations to treat conditions caused by microorganisms. Based on the popular use of this type of plants, the objective of this study was to obtain sequential extracts of increasing polarity from the branches of Fuchsia lycioides by maceration at room temperature and by the Soxhlet method at 60ºC, to later evaluate the antifungal capacity of the extracts against different clinical isolates of the Candida genus. The ethyl acetate extract exhibited strong anti-fungal activity, selectively inhibiting C. albicans strains with MIC and CMF values of 10 and 15 µg/mL, respectively; comparable with the drug itraconazole®. The analysis of the extract by GC-MS showed a high concentration of terpenoids (mainly phytol) and phenylpropanoids (mainly cinnamic acid), possibly responsible for the antifungal activity of the ethyl acetate extract of F. lycioides.

Covering: up to 2021Terpenoids are a diverse group of chemicals used in a wide range of industries. Microbial terpenoid production has the potential to displace traditional manufacturing of these compounds with renewable processes, but further titre improvements are needed to reach cost competitiveness. This review discusses strategies to increase terpenoid titres in Escherichia coli with a focus on alternative metabolic pathways. Alternative pathways can lead to improved titres by providing higher orthogonality to native metabolism that redirects carbon flux, by avoiding toxic intermediates, by bypassing highly-regulated or bottleneck steps, or by being shorter and thus more efficient and easier to manipulate. The canonical 2-C-methyl-d-erythritol 4-phosphate (MEP) and mevalonate (MVA) pathways are engineered to increase titres, sometimes using homologs from different species to address bottlenecks. Further, alternative terpenoid pathways, including additional entry points into the MEP and MVA pathways, archaeal MVA pathways, and new artificial pathways provide new tools to increase titres. Prenyl diphosphate synthases elongate terpenoid chains, and alternative homologs create orthogonal pathways and increase product diversity. Alternative sources of terpenoid synthases and modifying enzymes can also be better suited for E. coli expression. Mining the growing number of bacterial genomes for new bacterial terpenoid synthases and modifying enzymes identifies enzymes that outperform eukaryotic ones and expand microbial terpenoid production diversity. Terpenoid removal from cells is also crucial in production, and so terpenoid recovery and approaches to handle end-product toxicity increase titres. Combined, these strategies are contributing to current efforts to increase microbial terpenoid production towards commercial feasibility.

Covering: through June 2021 Terpenoids are the largest class of natural products recognised to date. While mostly known to humans as bioactive plant metabolites and part of essential oils, structurally diverse terpenoids are increasingly reported to be produced by microorganisms. For many of the compounds biological functions are yet unknown, but during the past years significant insights have been obtained for the role of terpenoids in microbial chemical ecology. Their functions include stress alleviation, maintenance of cell membrane integrity, photoprotection, attraction or repulsion of organisms, host growth promotion and defense. In this review we discuss the current knowledge of the biosynthesis and evolution of microbial terpenoids, and their ecological and biological roles in aquatic and terrestrial environments. Perspectives on their biotechnological applications, knowledge gaps and questions for future studies are discussed.

Covering: 1928-2021Ginkgo biloba L. is one of the most distinctive plants to have emerged on earth and has no close living relatives. Owing to its phylogenetic divergence from other plants, G. biloba contains many compounds with unique structures that have served to broaden the chemical diversity of herbal medicine. Examples of such compounds include terpene trilactones (ginkgolides), acylated flavonol glycosides (ginkgoghrelins), biflavones (ginkgetin), ginkgotides and ginkgolic acids. The extract of G. biloba leaf is used to prevent and/or treat cardiovascular diseases, while many ginkgo-derived compounds are currently at various stages of preclinical and clinical trials worldwide. The global annual sales of G. biloba products are estimated to total US$10 billion. However, the content and purity of the active compounds isolated by traditional methods are usually low and subject to varying environmental factors, making it difficult to meet the huge demand of the international market. This highlights the need to develop new strategies for the preparation of these characteristic compounds from G. biloba. In this review, we provide a detailed description of the structures and bioactivities of these compounds and summarize the recent research on the development of strategies for the synthesis, biosynthesis, and biotechnological production of the characteristic terpenoids, flavonoids, and alkylphenols/alkylphenolic acids of G. biloba. Our aim is to provide an important point of reference for all scientists who research ginkgo-related compounds for medicinal or other purposes.

Halocynthia roretzi, the edible ascidian, has been demonstrated to be an important source of bioactive natural metabolites. Here, we reported a novel terpenoid compound named Halorotetin A that was isolated from tunic ethanol extract of H. roretzi by silica gel column chromatography, preparative layer chromatography (PLC), and semipreparative-HPLC. 1H and 13C NMRs, 1H-1H COSY, HSQC, HMBC, NOESY, and HRESIMS profiles revealed that Halorotetin A was a novel terpenoid compound with antitumor potentials. We therefore treated the culture cells with Halorotetin A and found that it significantly inhibited the proliferation of a series of tumor cells by exerting cytotoxicity, especially for the liver carcinoma cell line (HepG-2 cells). Further studies revealed that Halorotetin A affected the expression of several genes associated with the development of hepatocellular carcinoma (HCC), including oncogenes (c-myc and c-met) and HCC suppressor genes (TP53 and KEAP1). In addition, we compared the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells. To our surprise, the cytotoxicities of Halorotetin A and doxorubicin on HepG-2 cells were similar at the same concentration and Halorotetin A did not significantly reduce the viability of the normal cells. Thus, our study identified a novel compound that significantly inhibited the proliferation of tumor cells, which provided the basis for the discovery of leading compounds for antitumor drugs.

The Lianhua Qingwen (LHQW) capsule is a popular traditional Chinese medicine for the treatment of viral respiratory diseases. In particular, it has been recently prescribed to treat infections caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, due to its complex composition, little attention has been directed toward the analysis of chemical constituents present in the LHQW capsule. This study presents a reliable and comprehensive approach to characterizing the chemical constituents present in LHQW by high-performance liquid chromatography-Q Exactive-Orbitrap mass spectrometry (HPLC-Q Exactive-Orbitrap-MS) coupled with gas chromatography-mass spectrometry (GC-MS). An automated library alignment method with a high mass accuracy (within 5 ppm) was used for the rapid identification of compounds. A total of 104 compounds, consisting of alkaloids, flavonoids, phenols, phenolic acids, phenylpropanoids, quinones, terpenoids, and other phytochemicals, were successfully characterized. In addition, the fragmentation pathways and characteristic fragments of some representative compounds were elucidated. GC-MS analysis was conducted to characterize the volatile compounds present in LHQW. In total, 17 compounds were putatively characterized by comparing the acquired data with that from the NIST library. The major constituent was menthol, and all the other compounds were terpenoids. This is the first comprehensive report on the identification of the major chemical constituents present in the LHQW capsule by HPLC-Q Exactive-Orbitrap-MS, coupled with GC-MS, and the results of this study can be used for the quality control and standardization of LHQW capsules., Graphical abstract Image 1, Highlights • The chemical components of LHQW capsule were revealed using HPLC-Q Exactive-Orbitrap-MS and GC-MS. • The approach combined HPLC-Q Exactive-Orbitrap-MS and GC-MS methods. • A library alignment method was used for the rapid identification of the chemical components. • In total, 120 compounds were putatively identified.

Background: Licorice is widely used as a hepatoprotective herb for thousands of years in Traditional Chinese Medicine, and its main chemical constituent glycyrrhizin (GL) is used as a treatment for chronic hepatitis in Japan for over 20 years. 18β-Glycyrrhetinic acid (GA) is the main active metabolite of GL. Objective: Series of GA derivatives were designed and synthesized, and their anti-HCV activities were screened to investigate structure-activity relationship (SAR). Besides, their in-silico ADMET properties were analyzed to search for promising lead compound for further identification of anti-HCV terpenoid candidate. Methods: GA derivatives were synthesized via reactions of oxidation, oxime, rearrangement, esterification and acylation, etc. In vitro anti-HCV activity of derivatives was tested on the HCV cell culture (HCVcc) system. In-silico ADMET properties analysis were performed via “pkCSM” and “SwissADME” platforms. Results: Eighteen GA derivatives were synthesized and their structures were confirmed by MS and NMR spectrums. All compounds exhibited superior HCV inhibitory activity to that of GA. Compound 2 possessed the most potent anti-HCV activity with IC50 value of 0.79 μM, which is nearly 58 times potent than SA (a previously reported potent anti-HCV terpenoids) and >200 times than GA. SAR revealed the introduction of 3-oxo, short-chain (C1-C3) aliphatic alcohols or cyclic aliphatic amines is conducive to improving anti-HCV activity. In-silico ADMET prediction demonstrated most of the potent compounds possessed favorable ADMET properties. Conclusion: Structural modification of GA at 3-position and 30-position is an effective approach to searching for potent anti-HCV agents. Compound 2, with the most potent anti-HCV activity and favorable in-silico ADMET properties, is a promising lead compound for further identification of anti-HCV terpenoid candidate.

Yeasts from the Candida parapsilosis complex are clinically relevant due to their high virulence and pathogenicity potential, such as adherence to epithelial cells and emission of filamentous structures, as well as their low susceptibility to antifungals. D-limonene, a natural compound, emerges as a promising alternative with previously described antibacterial, antiparasitic, and antifungal activity; however, its mechanisms of action and antivirulence activity against C. parapsilosis complex species have not been elucidated. Therefore, in the present study, we aimed to evaluate the antifungal and antivirulence action, as well as the mechanism of action of D-limonene against isolates from this complex. D-limonene exhibited relevant antifungal activity against C. parapsilosis complex yeasts, as well as excellent antivirulence activity by inhibiting yeast morphogenesis and adherence to the human epithelium. Furthermore, the apoptotic mechanism induced by this compound, which is not induced by oxidative stress, represents an important target for the development of new antifungal drugs.

Rosemary (Rosmarinus officinalis L.), a culinary herb of the family Lamiaceae, has promising anticancer activity. This overview has updated the current knowledge on the chemistry and anticancer properties of rosemary extract, carnosic acid, carnosol, and rosmanol, focusing on colon and prostate cancer cells since they are the most susceptible. The information was procured from Google, Google Scholar, PubMed, PubMed Central, Science Direct, J-Stage, and PubChem. Phenolic compounds isolated from the aerial parts of R. officinalis are flavonoids, phenolic acids, diterpenes, triterpenes, terpenoids, and phenylpropanoids. Some of the compounds are new to science, to the genus, and to the species. Almost 30 compounds possess anticancer properties. Rosemary extracts contain abietane diterpenes, with carnosic acid, carnosol, and rosmanol being the most common. Their molecular structures are similar to three fused aromatic rings. Carnosic acid has a –COOH group at C20, carnosol has a lactone ring occurs across the B ring, and rosmanol has a –OH group at C7. Against colon and prostate cancer cells, the rosemary extract and diterpenes inhibited cell viability and induced apoptosis and G2/M phase cell cycle arrest. The inhibition of cell migration and adhesion has also been reported. The rosemary extract and diterpenes also inhibited colon and prostate cancer xenograft in mice. Rosemary extract is more cytotoxic than the diterpenes due to its polyphenols such as flavonoids and triterpenes. In vitro and in vivo cytotoxic activities involve different molecular targets and signalling pathways. Some prospects and areas for future research are suggested.

Aim: Terpenes are natural compounds found in several organisms belonging to the animal and plant kingdom, therefore, constitute the largest class of natural products and were a rich reservoir of candidate compounds for drug discovery. The review aims to focus on the extensive potential of the anti-cancer terpenoid components obtained from natural plant species which may lead to the development of a variety of derived terpenoids moieties. Method: Literature survey has been carried out to determine the overwelhming potential of terpenoids. Results: The present article provides an overview of the development of the isoprene unit and the generation of the various types of terpenes that exhibits pharmacological potential. The anti-cancer activity of terpenoids appears promising and will potentially open more opportunities for cancer therapy. However, current studies are restricted to descriptive findings and some of them lack mechanistic insights and systematic structure--activity relationship studies. Future efforts into the systematic identification of the targets of terpenoids are believed to increase the chances of gaining breakthrough insights in the field. Conclusion: There is still hope that new therapeutic options for the control of cancer and any other painful syndromes will be developed from terpenes, which were proved to be great candidates for cancer therapeutics.

The Marchantiophyta (liverworts) are rich sources of phenolic substances, especially cyclic and acyclic bis-bibenzyls, which are rare natural products in the plant kingdom, together with bibenzyls and characteristic terpenoids. At present, more than 125 bis-bibenzyls have been found in liverworts. They are biosynthesized from the dimerization of lunularic acid via dihydrocoumaric acid and prelunularin. The structurally unusual cyclic and acyclic bis-bibenzyls show various biological activities such as antimicrobial, antifungal, cytotoxic, muscle relaxation, antioxidant, tubulin polymerization inhibitory, and antitrypanosomal activities, among others. The present review article deals with the distribution and structure of bis-bibenzyls, bibenzyls, and several characteristic ent-sesqui- and diterpenoids in liverworts. Furthermore, the biosynthesis and total syntheses and biological activities of bis-bibenzyls are also surveyed.

In recent years, marine-derived Penicillium fungi have received remarkable interest as a valuable source of novel natural products encompassing diverse chemical structures and bioactive properties. Mangroves, sediments, algae, and sponges are the four main sources of marine-derived Penicillium fungi. As of 2014, more than 390 novel natural products have been isolated from the marine- derived Penicillium fungi, mainly including polyketides, alkaloids, terpenoids, and macrolides. Biological investigations have shown that these compounds possess antimicrobial, anti-inflammatory, cytotoxic, and other activities with potential applications in new drug development. To provide an updated catalog of this field, our mini-review summarized the origins, structures, and bioactivities of 188 secondary metabolites from marine-derived Penicillium fungi based on bioactivities classification published from 2015 to 2020.

Phyllanthus is a large genus of shrubs, trees and rare herbs of the family Euphorbiaceae, comprising more than 600 species [1]. The aim of this project was to identify the phytochemicals present in P. niruri and the antidiabetic activity of the ethanolic extracts of the plant. The phytochemical analysis for alkaloids, flavonoids, anthraquinone, phenols, saponins, tannins, alkaloids, total phenolics, total flavonoids, carbohydrates and amino acids were made by following standard procedures. The antidiabetic property of the plant extract was evaluated using insulin as standards through inhibition of alphaamylase enzyme activity. The presence of saponins, alkaloids, tannins, flavonoids, phenols, terpenoids, carbohydrates, coumarins, anthraquinones and amino acids was observed. The total phenolic content in the extract was measured using catechol (standard) and a graph was plotted with concentration on X axis and absorbance on the Y axis. The total phenolic content was calculated. The calibration curves of α-amylase inhibition of Insulin and P. niruri was used to calculate the IC50 value.

Cancer is one of the leading causes of morbidity and mortality. Many treatment modalities have been developed and the need for plant derived therapeutic is growing due to the adverse effects of chemotherapeutic agents. The present study aims to discover the potential of two herbs Plectranthus amboinicus and Bacopa monnieri. Screening for the bioactives in the methanolic extracts of Plectranthus amboinicus and Bacopa monnieri stem showed the presence of alkaloids, flavonoids, terpenoids, phenols, saponins, carbohydrates. A comparative study on the cytotoxicity of methanolic extracts of the stem of these plants on lung epithelial cancer cell line A549 and normal fibroblast cell line L929 revealed that both extracts possess cancer cell specific cytotoxic activity. However, Bacopa monnieri stem extracts were found to be more effective in inducing cytotoxicity than Plectranthus amboinicus.

The purpose of the present study was to evaluate the growth potential and some rarely reported bioactivities (antioxidant, thrombolytic, anticoagulant, and anthelmintic) of Panax ginseng C.A. Meyer adventitious roots. To demonstrate the growth, shake flask and laboratory-scale bioreactor cultures have been employed. The obtained biomass was dried and extracted with water, ethanol, and methanol. The growth ratio (12.62 ± 1.03) observed in the bioreactor was significantly higher than in the shake flask culture. The presence of 10 different phytochemical classes, including carbohydrates, saponins, glycosides, and terpenoids were detected in qualitative estimation. Significant quantities of phenolics, flavonoids, proteins, and tannins were determined. Dose-dependent antioxidant activities were observed, and the IC50 values of methanolic and ethanolic extracts were very similar to the standard. The highest (29.26 ± 5.31%) thrombolytic potential was shown by the methanolic extract. The ethanolic extract significantly extended the coagulation times up to 2.5 fold. The highest anthelmintic properties in terms of paralyzing (2.21 ± 0.31 min) and killing (3.69 ± 0.41 min) of the parasitic worms were displayed by the aqueous extract. The in vitro root growth implies the commercial feasibility of ginseng production in Bangladesh and the demonstration of potential bioactivities strengthens medicinal implications and also offering new research areas.

Euphorbia deflexa, an endemic spurge from Greece, was investigated for the occurrence of its diterpene constituents. Through continuous monitoring by 1H NMR, 22 diterpenoids were isolated, including 16 previously undescribed compounds (euphodeflexins A-P), which belong to the jatrophane, ingenane, segetane, and pepluane diterpene types. Their chemical structures were elucidated through a combination of HRESIMS, NMR spectroscopy, and X-ray data. The isolated diterpenoids were tested against a panel of human cancer cell lines, as well as against two bacterial strains. Compounds 1, 13, and 17 were active against the HeLa cell line with IC50 values 9.9, 9.8, and 5.8 μM, respectively.

Nine new dolabrane-type diterpenoids, notoscarins A-I (1-9), including an unprecedented 6,18-cyclo-dolabrane-type diterpenoid (1) obtained through intramolecular cyclization, two rare 19-nor-2-chloro-dolabrane diterpenoids (2 and 3), six new related dolabrane-type diterpenoids (4-9), and one new butyrolactone derivative (10), were isolated from the Chinese liverwort Notoscyphus lutescens. The 6,18-cyclo-dolabrane and 19-nor-dolabrane carbon skeletons are reported for the first time. The structures of these compounds were determined on the basis of MS and NMR spectroscopic data, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Preliminary bioassays showed that compounds 1-10 exhibited moderate to weak quinone reductase-inducing activity in Hepa-1c1c7 cells.

A new ent-kaurane diterpenoid, named kaurane daturoside A (1), was isolated from the 70%-EtOH extract of dried pericarps of Datura metel L., along with six known terpenoids, 16α,17-dihydroxy-ent-kauran-19-diglycoside (2), cyclosieversioside F (3), astragaloside II (4), ginsenoside Rg1 (5), astrojanoside A (6), celerioside E (7). The isolated structures were elucidated by means of spectroscopic analyses, and the compounds 2, 3, 7 were separated from Solanaceae for the first time. Meanwhile, among isolates, compounds 2 and 5 exhibited anti-inflammatory activities against LPS-activated RAW264.7 cells (IC50μM).

The genus Delphinium is one of the essential members of the family Ranunculaceae. These species grow wild in North America, Europe, and Asia. They have demonstrated antioxidant, antimicrobial, and cytotoxic activities. Diterpenoid alkaloids are their main constituents and seem to be responsible for medicinal and toxic properties. The primary purpose of this paper is to review the therapeutic benefits of Delphinium species, chemical composition, and its medicinal uses, in addition to the reported toxic effects of these plants influencing different animals and humans.

One new clerodane-type diterpenoid, together with one known, was isolated from the leaves and twigs of C. krabas. The structures of these compounds were elucidated as krabasinolide A (1) and taraxerol (2) by spectroscopic methods (UV, IR, HRESIMS, 1 D, and 2 D NMR), and the relative stereochemistry was confirmed by X-ray diffraction analysis with graphite monochromated Mo-Kα (λ = 0.71073 Å) radiation at 296(2) K. Extracts and compounds 1-2 were evaluated for in vitro antiviral activity.

The mevalonate pathway is an upstream terpenoid biosynthetic route of terpenoids for providing the two five-carbon units, dimethylallyl diphosphate, and isopentenyl diphosphate. Recently, trans-anhydromevalonate-5-phosphate (tAHMP) was isolated as a new biosynthetic intermediate of the archaeal mevalonate pathway. In this study, we would like to report the first synthesis of tAHMP and its enzymatic transformation using one of the key enzymes, mevalonate-5-phosphate dehydratase from a hyperthermophilic archaeon, Aeropyrum pernix. Starting from methyl tetrolate, a Cu-catalyzed allylation provided an E-trisubstituted olefin in a stereoselective manner. The resulting E-olefin was transformed to tAHMP by cleavage of the olefin and phosphorylation. The structure of the synthetic tAHMP was unambiguously determined by NOESY analysis.

The chemical compositions and antioxidant evaluation of the essential oils (EOs) obtained by hydrodistillation from the leaf and stem of Indigofera spicata Forssk (Fabaceae) grown in Nigeria have been studied. The EOs were analyzed using gas chromatography coupled with mass spectrometry (GC-MS) and the antioxidant potential was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging ability method. The essential oils from the leaf and stem obtained in 0.007% and 0.009% yield have been found to contain 18 and 17 compounds respectively. 13 compounds identified in the stem EOs make 90.2% of it. Sesquiterpenes (49.2%) and alcohols (30.7%) are dominant classes of compounds in the leaf EOs, with the most abundant compounds as caryophyllene (38.2%), humulene (6.2%) and m-eugenol (27.5%). Whereas esters (47.2%), and monoterpenoids (20.8%) dominate the stem essential oils with major constituents as linalyl acetate (23.9%), α-terpinyl acetate (12.8%), 3,5,5-trimethyhexyl acetate (9.4%), and linalool (20.8%). Common to both EOs were linalool, (leaf, 1.9%) caryophyllene (stem 5.9%), linanyl acetate (leaf, 2.5%). Comparison of the composition pattern of the leaf and stem EOs of I. spicata revealed significant qualitative and quantitative differences. Monoterpenes, sesquiterpenoid, diterpenoid, epoxide and ether were exclusive to the leaf oil while saturated, unsaturated hydrocarbons and anhydride were found only in the stem oil. The IC50 values of antioxidant evaluations show the leaf EO (36.97 µg/mL) has more potential than the stem oil (39.89 µg/mL) and comparable to that of the controls Vitamin C and Butylhydroxyl Anisole with IC50 values 24.20 and 24.21 µg/mL respectively. Most of these identified compounds have been known for various pharmacological activities such as antioxidant, antitumor, anti-inflammatory, even as fragrances and the antioxidant potential of the oils justify the ethno-medicinal uses of I. spicata. Key words: Indigofera spicata, linalool, m-eugenol, caryophyllene, essential oil, sesquiterpene, antioxidant, 2,2-diphenyl-1-picrylhydrazyl (DPPH).

Eukaryotic green microalgae show considerable promise for the sustainable light-driven biosynthesis of high-value fine chemicals, especially terpenoids because of their fast and inexpensive phototrophic growth. Here, the novel isopentenol utilization pathway (IUP) was introduced into Chlamydomonas reinhardtii to enhance the hemiterpene (isopentenyl pyrophosphate, IPP) titers. Then, diphosphate isomerase (IDI) and limonene synthase (MsLS) were further inserted for limonene production. Transgenic algae showed 8.6-fold increase in IPP compared with the wild type, and 23-fold increase in limonene production compared with a single MsLS expressing strain. Following the culture optimization, the highest limonene production reached 117 µg/L, when the strain was cultured in a opt2 medium supplemented with 10 mM isoprenol under a light: dark regimen. This demonstrates that transgenic algae expressing the IUP represent an ideal chassis for the high-value terpenoid production. The IUP will facilitate further the metabolic and enzyme engineering to enhance the terpenoid titers by significantly reducing the number of enzyme steps required for an optimal biosynthesis.

In addition to phytocannabinoids, cannabis contains terpenoids that are claimed to have a myriad of effects on the body. We tested a panel of five common cannabis terpenoids, myrcene, linalool, limonene, α-pinene and nerolidol, in two neuronal models, autaptic hippocampal neurons and dorsal root ganglion (DRG) neurons. Autaptic neurons express a form of cannabinoid CB1 receptor-dependent retrograde plasticity while DRGs express a variety of transient receptor potential (TRP) channels. Most terpenoids had little or no effect on neuronal cannabinoid signaling. The exception was nerolidol, which inhibited endocannabinoid signaling. Notably, this is not via inhibition of CB1 receptors but by inhibiting some aspect of 2-arachidonoylglycerol (2-AG) production/delivery; the mechanism does not involve reducing the activity of the 2-AG-synthesizing diacylglycerol lipases (DAGLs). Nerolidol was also the only terpenoid that activated a sustained calcium response in a small (7%) subpopulation of DRGs. In summary, we found that only one of five terpenoids tested had notable effects on cannabinoid signaling in two neuronal models. Our results suggest that a few terpenoids may indeed interact with some components of the cannabinoid signaling system and may therefore offer interesting insights upon further study.

Ipomoea aquatica is a common green leafy vegetable that has numerous uses in traditional medicine. This study focused on the determination of the cytotoxic, antiradical, and antidiabetic properties of various fractions of the I. aquatica methanolic extract, as well as on the tentative identification of some bioactive compounds in the same fractions. The cytotoxicity was determined by the brine shrimp lethal test. The antioxidant activities of the I. aquatica fractions were investigated through 3 assays. The antidiabetic activity (in vitro) was measured by α-glucosidase and α-amylase inhibition assays. Phytochemical qualitative analyses demonstrated the presence of alkaloids, terpenoids, phenols, and flavonoids in the ethyl acetate-methanol and methanol fractions. The total phenolic and total flavonoid contents were found to be highest in the ethyl acetate-MeOH fractions. The evaluation of the cytotoxicity showed that the hexane-dichloromethane fraction is the most toxic, while the others are moderately toxic. The antioxidant activity assays showed that the ethyl acetate-MeOH fractions are the most potent, while the α-glucosidase and α-amylase assays revealed that the hexane-dichloromethane fraction might contain a potent antidiabetic agent. Some bioactive substances in the MeOH fractions, such as salicylic acid glucoside, 1-O-sinapoyl-β-D-glucose derivative, and dihydroferulic acid derivative, were tentatively identified. To the best of our knowledge, this is the first report to detect and identify these compounds in this species. Based on the results of this study, it may be concluded that I. aquatica is a potent antioxidant agent and could be a good candidate as a natural antioxidant in food and therapeutics.

Terpenoid indole (TIAs) and β-carboline alkaloids (BCAs), such as suppressant reserpine, vasodilatory yohimbine, and antimalarial quinine, are natural compounds derived from strictosidine. These compounds can exert powerful pharmacological effects but be obtained from limited source in nature. the whole biosynthetic pathway of TIAs and BCAs, The Pictet-Spengler reaction catalyzed by strictosidine synthase (STR; EC: 4.3.3.2) is the rate-limiting step. Therefore, it is necessary to investigate their biosynthesis pathways, especially the role of STR, and related findings will support the biosynthetic generation of natural and unnatural compounds. This review summarizes the latest studies concerning the function of STR in TIA and BCA biosynthesis, and illustrates the compounds derived from strictosidine. The substrate specificity of STR based on its structure is also summarized. Proteins that contain six-bladed four-stranded β-propeller folds in many organisms, other than plants, are listed. The presence of these folds may lead to similar functions among organisms. The expression of STR gene can greatly influence the production of many compounds. STR is mainly applied to product various valuable drugs in plant cell suspension culture and biosynthesis in other carriers.

Three new aconitine-type C19-diterpenoid alkaloid namely novolunines A (1), B (2), and C (3), along with fifteen known diterpenoid alkaloids were isolated from the roots of Aconitum novoluridum, whose phytochemical investigations have never been reported before. The structures of three new alkaloids were established on the basis of spectra data (high-resolution electrospray ionization (HR-ESI)-MS, IR, one dimensional (1D)- and 2D-NMR). Noteworthily, novolunines A (1) and B (2) are two diterpenoid alkaloids bearing conformational isomerism. In addition, the diterpenoid alkaloids 1-3 did not show any anti-acetylcholinesterase (AChE) or anti-inflammatory activities.

Herbal remedies have been employed for the treatment and management of different diseases for ages. Herbal medicines are a promising choice over modern synthetic drugs because of their low side effects and are thus considered to be safe and effective in treating human diseases. Lagenaria siceraria (Mol.) Standley fruit (Bottle gourd) belongs to the Cucurbitaceae family that has been used in a different system of traditional medication to treat various diseases. This is a domestic plant that provides food as well as medication. This vegetable have low caloric values and high water contents. The edible portion of it contains phytochemicals like vitamins, proteins, choline, minerals, terpenoids, flavonoids, etc. Several bioactive compounds have been isolated from L. siceraria, including triterpenoids, sterols, cucurbitacins, flavones, C-glycosides and β-glycosides. Researchers have evaluated various parts of this plant viz. fruit, root, flowers, and leaves for pharmacological activities like antianxiety, antidepressant, diuretic, antimicrobial, cytotoxic, antihyperlipidemic, cardio protective, analgesic, anti-inflammatory, anthelmintic, anti-hyperglycemic, antihepatotoxic, anti-urolithiatic, antistress, antiulcer, anticancer, hepatoprotective, anthelmintic, immunomodulatory, and antioxidant. In this review, an attempt has been made to explore its phytochemical constituents, traditional, medicinal, and pharmacological uses to highlight the therapeutic importance of this well-known plant. This would be helpful in reviving its importance and will highlight its several promising aspects to encourage researchers for further research on L. siceraria.

Reactive oxygen species are implicated in multiple pathological conditions including erectile dysfunction. This study evaluated the in vitro and in vivo antioxidant potential of the methanolic extracts of Inula glomerata and Salacia kraussii. The plant materials were pulverized and extracted with methanol. The phytochemical analysis, ability of the crude extracts to scavenge free radicals (ABTS, DPPH, NO.) in vitro as well as the total phenolic and flavonoid contents was investigated. In vivo, antioxidant potentials of the crude extracts (50/250 mg/kg body weight) were determined in an erectile dysfunction rat model. The phytochemical analysis revealed that both plants contain flavonoids, tannins, terpenoids, and alkaloids. The crude extracts at varying degree of efficiency, scavenged ABTS and DPPH radicals. The crude extracts at low concentrations (50 mg/kg b.w) significantly (p

A chemical investigation on the roots of Aconitum episcopale afforded three undescribed aconitine-type C19-diterpenoid alkaloids, episcopalines A-C (1-3). The structures of the new compounds were elucidated by spectroscopic analysis (NMR, IR, UV, and MS). The isolated alkaloids were tested in vivo for their antinociceptive properties. As a result, episcopaline B (2) showed potent antinociceptive effect and its ID50 value (55.0 μmol/kg) was 2-fold less than those of the positive control drugs aspirin and acetaminophen.

A pair of new lignans [(+)- 1 and (-)- 1] and three new compounds (2-4), together with a known compound 5, were isolated from the fruits of Xanthium italicum Moretti. The structures of these compounds were determined on the basis of spectroscopic analysis, particularly HR-ESI-MS and 1 D and 2 D NMR. Compounds 2 and 3 showed antinociceptive effects in an acetic acid-induced writhing test in mice with the writhe inhibition rates of 80.50% and 67.89% at the dose of 20 mg/kg, respectively.

The use of medicinal plants as alternative therapy for the treatment of microbial infections is significant in the maintenance of good health, especially in developing countries. The aim of this study was to determine the phytochemical composition and antimicrobial activity of Buchholzia coriacea and Psychotria microphylla leaf extracts on bacteria isolated from aquatic environments in Nigeria. Exactly 736 water samples from boreholes, ponds, rivers, streams, and wells respectively were collected for this study. Antimicrobial activity of B. coriacea and P. microphylla leaf extracts were determined using standard microbiological techniques. Phytochemical and chemical constituents of the herbal extracts were determined using standard analytical techniques. Bacteria isolated from the water samples were Aeromonas hydrophila (n = 103), Escherichia coli (n = 118), and Vibrio cholerae (n = 87). extracts of B. coriacea and P. microphylla showed appreciable antibacterial activities. B. coriacea and P. microphylla leaf extracts showed the presence of minerals, alkaloids, protein, terpenoids, phenols, flavonoids, glycosides, steroids, tannins, and vitamins. Plant extracts used in this study exhibited an amazing antibacterial activity against bacterial isolates from the water bodies. Thus, B. coriacea and P. microphylla plants should be further explored to determine the active component(s) responsible for their antibacterial activity. Key words: Antimicrobial activity, B. coriacea, P. microphylla, leaf extracts, bacteria, aquatic environments, phytochemical composition.

Objectives The finding of alternative medicine for malarial treatment still has become a substantial demand. The plant is one of the potential sources of drugs, among other natural sources. Artocarpus species showed great potential as the antimalarial source. This study aims to obtain active antimalarial fractions from Artocarpus sericicarpus stem bark. Methods Stem bark of A. sericicarpus was extracted by ultrasonic-assisted extraction method using n-hexane, dichloromethane, and methanol as solvents. Fractionation of dichloromethane extract was conducted by open column chromatography using octadecyl silica as a stationary phase and gradient acetonitrile-water as a mobile phase. The antimalarial activity was determined by lactate dehydrogenase (LDH) assay against Plasmodium falciparum 3D7 strain. Results A. sericicarpus n-hexane, dichloromethane, and methanol extracts were showed antimalarial activity with an IC50 value of >4, 2.11, and >4 μg/mL, respectively. Fractionation of dichloromethane extract was obtained 13 fractions. Seven of the 13 fractions tested showed antimalarial activity. Fraction-6 performed the highest inhibition with an IC50 value of 1.53 ± 0.04 μg/mL. Phytochemistry screening revealed that Fraction-6 contains flavonoid, polyphenol, and terpenoid compounds that can take a role in its antimalarial activity. Conclusions A. sericicarpus contains antimalarial substances mainly in Fraction-6, which strongly inhibited the growth of P. falciparum. The flavonoid, polyphenol, and terpenoid compounds were identified in Fraction-6, which need to be further isolated to obtain and elucidate the active antimalarial compounds.

Objectives This study aims to evaluate the antioxidant and antiviral potency of n-hexane, ethyl acetate and, water fractions of Begonia medicinalis Ardi & D.C.Thomas as well as to identify the chemical constituents. Methods Assays for antioxidant and antiviral activity (HIV-1) were carried out on MT-4 cells infected with HIV using the DPPH method and the determination of the cytopathic effect. Meanwhile, GC-MS was used to identify the chemical compounds. Results The determination of antioxidants showed that all fractions possessed potent activity with the IC50 ranging from 2.61 to 8.26 μg/mL. From the antiviral activity of MT-4 cells infected by HIV, the n-hexane fraction of B. medicinalis showed the most potency with the IC50 of 0.04 ± 0.05 μg/mL. It has less cytotoxicity (11.08 ± 4.60 μg/mL) affording the high selectivity index of 238.80. Furthermore, GC-MS analysis of n-hexane fraction found the major compound of carboxylic acid derivate with the area percentage of 76.4% and the presence of phenolic compounds (8.38%). Meanwhile, in water fraction, terpenoids were found in a higher concentration (10.05%) than others. Conclusions Therefore, this study supports the application of B. medicinalis as a herbal medicine for antioxidant and antiviral.

The optimal parameters influencing the extraction of the sum of terpenoid alcohol esters from the aerial part of Ferula tschimganica and purification of the obtained extract were found and made it possible to produce a final substance without green coloration. The technology for producing the sum of terpenoid alcohol esters from the aerial part of F. tschimganica was developed. Aspectrophotometric method for quantitative determination of the sum of terpenoid alcohol esters in chimphestrol substance (working name of the created agent) was proposed. Pharmacological studies found that terpenoid alcohol esters from the aerial part of F. tschimganica at a dose of 1 mg/kg exhibited a pronounced estrogenic effect in experiments on both immature and ovariectomized rats that was comparable to that of tefestrol and slightly inferior to that of the synthetic estrogenic drug Synestrol.

An extract of a Sinularia sp. soft coral showed inhibitory activity against the E3-ubiquitin ligase casitas B-lineage lymphoma proto-oncogene B (Cbl-b). Subsequent bioassay-guided separation of the extract provided a series of terpenoid-derived spermidine and spermine amides that were named sinularamides A–G (1–7). Compounds 1–7 represent new natural products; however, sinularamide A (1) was previously reported as a synthetic end product. The structures of sinularamides A–G (1–7) were elucidated by analysis of spectroscopic and spectrometric data from NMR, IR, and HRESIMS experiments and by comparison with literature data. All of the isolated compounds showed Cbl-b inhibitory activities with IC(50) values that ranged from approximately 6.5 to 33 μM.

Two new meroterpenoids, aspermeroterpenes D and E (1 and 2), two new ophiobolin-type sesterterpenoids, the C-18 epimers of 18,19-dihydro-18-methoxy-19-hydroxyophiobolin P (6 and 7), and two new drimane-type sesquiterpenoids, 3S-hydroxystrobilactone A (8) and 6-epi-strobilactone A (9), along with 11 known terpenoids (3-5 and 10-17) were isolated from the cultures of the algicolous fungus Aspergillus sp. RR-YLW-12, derived from the red alga Rhodomela confervoides. The structures and relative configurations of new compounds were established by detailed spectroscopic analysis of NMR and HRMS experiments, and the absolute configurations were assigned by X-ray diffraction experiments and comparison of their experimental and calculated ECD spectra. Compound 1 features a rare 6/6/6/6/5 pentacyclic system with a meroterpenoid skeleton, and the structure of terretonin E (3) was revised in this study. Compound 4 showed significant inhibitory activities against three microalgae, Prorocentrum donghaiense, Heterosigma akashiwo, and Chattonella marina, with IC50 values of 10.5, 5.2, and 3.1 μg/mL, respectively.

A chemical investigation on the EtOAc extract of the endophytic fungus Eutypella scoparia SCBG-8 led to the isolation of eight new sesquiterpenes eutyscoparins A-H (1-8), one C-28 steroid eutyscoparene A (9), one triterpenoid eutyscoparene B (10), six known terpenoids, and two known steroids. Their structures including absolute configurations were established on the basis of spectroscopic data analysis, single-crystal X-ray diffraction experiments, and electronic circular dichroism (ECD) calculations. Compound 7 displayed antibacterial activity against S. aureus and MRSA (methicillin-resistant Staphylococcus aureus) with MIC values of 6.3 μg/mL.

Introduction The genus Aster plants have been widely used for thousands of years in the Qinghai-Tibetan Plateau for the clearing of heat, detoxification, and the treatment of seasonal pandemic diseases. Although the presence of several flavonoid compounds in Aster has been reported by previous studies, the diversity of secondary metabolites within and among species is relatively unknown. Objective The metabolite profile of one Aster species was systematically compared with those of other taxa to find potential chemotaxonomic markers, delimit species, and assess chemodiversity. Method Samples of the above-ground parts of 11 Aster species were collected and their metabolites were analysed by ultra-high performance liquid chromatography with photodiode array detection and quadrupole time-of-flight tandem mass spectrometry. Unsupervised principal component analysis, supervised orthogonal partial least-squares discriminant analysis, heatmap analysis, and hierarchical cluster analysis were employed to analyse 95 representative samples from 11 Aster species and determine species-specific chemical markers based on a metabolomics database. Results Six phenolic acids and flavonoids were detected and quantified in all Aster species, suggesting that these compounds may be common constituents in the Aster genus. Metabolite analysis showed terpenoid compounds to be potential chemical markers for interspecies differentiation. Ent-kaurane-type diterpenoid glycosides were the main class of compounds in all Aster species except for A. farreri, which mainly contained oleanane-type pentacyclic triterpenoids. Diterpenoid glycosides were low-content chemotaxonomic markers and were detected for the first time in Aster species from the Qinghai-Tibetan Plateau. Conclusion Chemotaxonomy and metabolomics were used to support the phylogenic relationships of the Aster genus.

Prenyl moieties are commonly encountered in the natural products of terpenoid and mixed biosynthetic origin. The reactivity of unsaturated prenyl motifs is less recognized and shown here to affect the acyclic Rhodiola rosea monoterpene glycoside, kenposide A (8), which oxidizes readily on silica gel when exposed to air. The major degradation product mediated under these conditions was a new aldehyde, 9. Exhibiting a shortened carbon skeleton formed through the breakdown of the terminal isopropenyl group, 9 is prone to acetalization in protic solvents. Further investigation of minor degradation products of both 8 and 8-prenylapigenin (8-PA, 12), a flavonoid with an ortho-prenyl substituent, revealed that the aldehyde formation was likely realized through epoxidation and subsequent cleavage at the prenyl olefinic bond. Employment of 1H NMR full spin analysis (HiFSA) achieved the assignment of all chemical shifts and coupling constants of the investigated terpenoids and facilitated the structural validation of the degradation product, 9. This study indicates that prenylated compounds are generally susceptible to oxidative degradation, particularly in the presence of catalytic mediators, but also under physiological conditions. Such oxidative artifact/metabolite formation leads to a series of compounds with prenyl-derived (cyclic) partial structures that are analogous to species formed during Phase I metabolism in vivo. Phytochemical and pharmacological studies should take precautions or at least consider the impact of (unavoidable) exposure of prenyl-containing compounds to catalytic and/or oxidative conditions.