Recent Developments in Enzymatic and Microbial Biosynthesis of Flavor and Fragrance Molecules

Flavors and fragrances are an important class of specialty chemicals for which interest in biomanufacturing has risen during recent years. These naturally occurring compounds are often amenable to biosynthesis using purified enzyme catalysts or metabolically engineered microbial cells in fermentation processes. In this review, we provide a brief overview of the categories of molecules that have received the greatest interest, both academically and industrially, by examining scholarly publications as well as patent literature. Overall, we seek to highlight innovations in the key reaction steps and microbial hosts used in flavor and fragrance manufacturing.

Sniffing Out the Sustainable Future: The Renewability Revolution in Fragrance Chemistry

In this review, the impact of the transition from today's resource-wasting petrochemical economy towards a 100/100 renewable and biodegradable future is discussed with respect to the fragrance families: "citrus", "green", "fruity", "floral", "floriental", "oriental", "woody", "chypre" and "fougère". After benchmark data on ingredients usage, definitions on biodegradation and sustainability are given. Celebrating the 150th anniversary of synthetic vanillin, its historic synthesis from renewable starting materials serves as introduction. In the grand scheme of things, citrus scents upcycled from the beverages industry, are already an ideal case for 100/100 with new opportunities for artificial essential oils. In the fruity domain, transparent and lactonic ingredients are available in a sustainable manner. However, in the domain of green odorants, there is a lack of green chemistry for important key materials. In the floral family, renewability is more critical than biodegradability, but cost is an issue. Thanks to Ambrox and maltol, florientals and orientals will persist, while woody notes severely lack an Iso E Super replacer. In the chypre genre, patchouli became the new moss, but more musks are increasingly in demand. With their high percentage of linalool and dihydromyrcenol, the construction of fougères could well become a precedent for other families, despite challenges in vetiver and salicylates. Still, the challenges exemplified here create immense opportunities for new perfumery materials.

Optimizing the Vanillin-Acid Sulfuric Method to Total Saponin Content in Leaves of Yerba Mate Clones

Yerba mate (Ilex paraguariensis) is a forest species consumed in the form of non-alcoholic beverages in South America, with applications in foods, cosmetics, and pharmaceutical industries. The species leaves are globally recognized for their important bioactive compounds, including, saponins. We adjusted the vanillin-acid sulfuric method for determining spectrophotometrically the total saponin in yerba mate leaves. Seeking to maximize the extraction of saponins from leaves, a Doehlert design combined with Response Surface Methodology (RSM) was used, considering ethanol:water ratios and ultrasound times. In addition, the same methodology was used for the analysis of times and temperatures in the vanillin-sulfuric acid reaction heating. The contents of total saponin in mature leaves were compared in four yerba mate clones. The extraction was maximized using 40 % ethanol:60 % water and 60 minutes of ultrasound assisted extraction (UAE) without heating. For the reaction conditions, 70 °C for 10 minutes heating is recommended, and UV/Vis reading from 460 to 680 nm. Using the optimized methodology, total saponin contents ranged from 28.43 to 53.09 mg g-1 in the four yerba mate clones. The significant difference in saponin contents between clones indicate great genetic diversity and potential for clones' selection and extraction of these compounds from yerba mate leaves.

Discovery and characterisation of a broderol-like illudin, omphaderol in the mycelial extracts of Omphalotus mexicanus (Omphalotaceae) using UPLC-QTOF-MS and NMR spectroscopy

INTRODUCTION

The genus Omphalotus, in particular the "Jack-O'Lantern mushrooms" Omphalotus illudens and Omphalotus olearius, are famous for the production of the DNA-alkylating illudins. A lesser-known species, Omphalotus mexicanus, native to Central America, also produces cytotoxic illudins S and M, but its minor secondary metabolites are yet to be investigated.

OBJECTIVE

To identify, isolate, and elucidate the structure of novel secondary metabolites of the illudin family in mycelial extracts of O. mexicanus from submerse cultivation.

METHODOLOGY

A fermentation of the fungus in 15 L stirred tank bioreactors is described. Mycelial extracts were separated using a combination of flash chromatography with preparative RP-C18 high-performance liquid chromatography (HPLC). Analysis of metabolites was done using an ultrahigh-performance liquid chromatography ultraviolet diode array detector (UPLC-UV-DAD) system coupled to an electrospray ionisation quadrupole time-of-flight (ESI-QTOF) mass spectrometer. Structures were elucidated using one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance spectroscopy (NMR) techniques followed by comparison of experimental and simulated electronic circular dichroism (ECD) spectra to determine absolute configurations.

RESULTS

Two novel illudin derivatives, for which we propose the names omphaderol (1) and illudaneol B (2), as well as illudaneol (3) and the unusual cyclobutylcyclopentane illudosin (4), were isolated from the mycelia and characterised.

CONCLUSION

Particularly the illudaneol derivatives with their high titers may be potential building blocks for an alternative semisynthetic route to new illudin derivatives with improved medical properties. Additionally, the findings improve the knowledge of minor illudin compounds in the mycelial extract of this fungus and may be of significance for future biosynthetic studies of the illudins.

Improved Quantification of Geosmin and 2-Methylisoborneol in Farmed Fish Using Stable Isotope Dilution Gas Chromatography-Mass Spectrometry

A requisite to improving the taste and odor attributes of farmed fish is the availability of accurate and practical analytical methods to quantify 2-methylisoborneol (MIB) and geosmin (GSM). Solid-phase microextraction (SPME) enables reliable measurement of nanogram per liter quantities of MIB and GSM in water. In contrast, direct headspace (HS)-SPME of biological matrices with variable proximate compositions can increase bias and uncertainty in off-flavor determinations. Analytical recovery plays a crucial role in the accurate determination of MIB and GSM in fish, and this study investigates strategies to maximize and account for this recovery factor. MIB and GSM values in off-flavor catfish and trout were measured using direct HS-SPME and distillation as sample preparation techniques. Trout samples prepared by distillation yielded 10-fold higher GSM recoveries than those from direct HS-SPME (31% versus 3%). A stable isotope dilution method (SIDM) was implemented by routinely spiking samples with known quantities of deuterium-labeled MIB and GSM, allowing for the correction of sample-to-sample recovery deviations. SIDM-determined GSM values generated recoveries of 106 and 95% for direct HS-SPME and distilled trout, respectively. Aspects of the strategies and techniques presented can be incorporated into existing analytical methods to improve the accuracy and sample throughput. Particularly, routine inclusion of SIDM in the evaluation of MIB and GSM can facilitate identification of reliable practices to control off-flavors in aquaculture.

Functional Plasticity of a Viral Terpene Synthase, OILTS, that Shows Non-Specific Metal Cofactor Binding and Metal-dependent Biosynthesis

OILTS is a viral class I terpene synthase found from the giant virus Orpheovirus IHUMI-LCC2. It exhibits a unique structure and demonstrates high plasticity to metal cofactors, allowing it to biosynthesize different cyclic terpene frameworks. Notably, while OILTS produces only (+)-germacrene D-4-ol with the most common cofactor, Mg2+, it also biosynthesizes a different cyclic terpene, (+)-cubebol, with Mn2+, Co2+, or Ni2+, presenting a rare instance of cofactor-dependent enzyme catalysis. This is the first report of (+)-cubebol biosynthesis, to our knowledge. In addition, OILTS can uptake Zn2+ as a cofactor, which is uncommon among ordinary terpene synthases. These findings suggest that OILTS's functional plasticity may benefit the virus in diverse host environments, highlighting potential evolutionary implications.

Potential Regulatory Networks and Heterosis for Flavonoid and Terpenoid Contents in Pak Choi: Metabolomic and Transcriptome Analyses

Pak choi exhibits a diverse color range and serves as a rich source of flavonoids and terpenoids. However, the mechanisms underlying the heterosis and coordinated regulation of these compounds-particularly isorhamnetin-remain unclear. This study involved three hybrid combinations and the detection of 528 metabolites from all combinations, including 26 flavonoids and 88 terpenoids, through untargeted metabolomics. Analysis of differential metabolites indicated that the heterosis for the flavonoid and terpenoid contents was parent-dependent, and positive heterosis was observed for isorhamnetin in the two hybrid combinations (SZQ, 002 and HMG, ZMG). Moreover, there was a high transcription level of flavone 3'-O-methyltransferase, which is involved in isorhamnetin biosynthesis. The third group was considered the ideal hybrid combination for investigating the heterosis of flavonoid and terpenoid contents. Transcriptome analysis identified a total of 12,652 DEGs (TPM > 1) in various groups that were used for comparison, and DEGs encoding enzymes involved in various categories, including "carotenoid bio-synthesis" and "anthocyanin biosynthesis", were enriched in the hybrid combination (SZQ, 002). Moreover, the category of anthocyanin biosynthesis also was enriched in the hybrid combination (HMG, ZMG). The flavonoid pathway demonstrated more differential metabolites than the terpenoid pathway did. The WGCNA demonstrated notable positive correlations between the dark-green modules and many flavonoids and terpenoids. Moreover, there were 23 ERF genes in the co-expression network (r ≥ 0.90 and p < 0.05). Thus, ERF genes may play a significant role in regulating flavonoid and terpenoid biosynthesis. These findings enhance our understanding of the heterosis and coordinated regulation of flavonoid and terpenoid biosynthesis in pak choi, offering insights for genomics-based breeding improvements.

The Ethyl Acetate Extract of Caulerpa microphysa Promotes Collagen Homeostasis and Inhibits Inflammation in the Skin

Inflammation and collagen-degrading enzymes' overexpression promote collagen decomposition, which affects the structural integrity of the extracellular matrix. The polysaccharide and peptide extracts of the green alga Caulerpa microphysa (C. microphysa) have been proven to have anti-inflammatory, wound healing, and antioxidant effects in vivo and in vitro. However, the biological properties of the non-water-soluble components of C. microphysa are still unknown. In the present study, we demonstrated the higher effective anti-inflammatory functions of C. microphysa ethyl acetate (EA) extract than water extract up to 16-30% in LPS-induced HaCaT cells, including reducing the production of interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor-α (TNF-α). Furthermore, the excellent collagen homeostasis effects from C. microphysa were proven by suppressing the matrix metalloproteinase-1 (MMP-1) secretion, enhancing type 1 procollagen and collagen expressions dose-dependently in WS1 cells. Moreover, using UHPLC-QTOF-MS analysis, four terpenoids, siphonaxanthin, caulerpenyne, caulerpal A, and caulerpal B, were identified and may be involved in the superior collagen homeostasis and anti-inflammatory effects of the C. microphysa EA extract.

Natural Herbal Compounds Exerting an Antidepressant Effect through Hypothalamic-Pituitary-Adrenal Axis Regulation

Depression is a common mental illness that damages the life and health of patients and causes economic burden, and HPA (hypothalamic-pituitary-adrenal) axis dysfunction is considered to be one of the important factors leading to depression. In this case, it is essential to explore possible treatment methods by using natural compounds with HPA axis regulating and antidepressant effects. However, no one has reviewed it so far. Therefore, the purpose of this review is to systematically sort out the related natural products that play an antidepressant role by regulating the function of the HPA axis. Natural products are divided into flavonoids, polyphenols, terpenoids, saponins, polysaccharides and so on according to their chemical structures, which play a variety of biological activities such as regulating the HPA axis, anti-inflammation and neuroprotection. These effects may provide a useful reference for the potential treatment of depression so as to develop new antidepressants.

Ménage à trois: light, terpenoids, and quality of plants

In controlled environment agriculture (CEA), light is used to impact terpenoid production and improve plant quality. In this review we discuss various aspects of light as important regulators of terpenoid production in different plant organs. Spectral quality primarily modifies terpenoid profiles, while intensity and photoperiod influence abundances. The central regulator of light signal transduction elongated hypocotyl 5 (HY5) controls transcriptional regulation of terpenoids under UV, red (R), and blue (B) light. The larger the fraction of R and green (G) light, the more beneficial the effect on monoterpenoid and sesquiterpenoid biosynthesis, and such an effect may depend on the presence of B light. A large fraction of R light is mostly detrimental to tetraterpenoid production. We conclude that light is a promising tool to steer terpenoid production and potentially tailor the quality of plants.

Innovative Encapsulation Strategies for Food, Industrial, and Pharmaceutical Applications

Encapsulation has emerged as a vitally important tool for protecting the integrity of critical chemicals and improving the delivery mechanisms of natural/synthetic drugs, enabling the controlled release of ingredients and the maintenance of their chemical, physical, and biological properties. It is well known that essential oils (EOs) provide a valuable alternative for food preservation, as they help reducing the deterioration of foodstuffs as well as the proliferation of pathogens. Nevertheless, EOs are highly volatile and lipophilic, rendering them insoluble in aqueous systems. In addition, their secondary metabolites are extremely susceptible to environmental factors such as humidity, temperature, light, and oxygen. Therefore, encapsulation of EOs is an innovative option not only for preserving these substances but also for promoting their stability, controlling their release, and optimizing their efficiency and bioavailability. In this sense, this review aimed to describe current techniques and approaches used to incorporate natural hydrophobic compounds, covering EOs. It also examines whether encapsulation technology can be used efficiently in drug discovery and development. Studies have shown that microencapsulation, the use of nanoparticle, and liposomal are the most effective techniques for encapsulating EOs. Other encapsulation systems included spray drying, coacervation, and emulsification.

Phytochemical composition of the diethyl ether extract of Artemisia lactiflora Wall. ex DC and its antimetastatic activity in human lung cancer cells

Artemisia lactiflora Wall. ex DC. is a traditional Chinese medicinal plant used in the treatment of menstrual and hepatic disorders due to its antioxidant and anti-inflammatory properties. However, its anti-metastatic activity, which is the clinical challenge of lung cancer treatment, has not yet been reported. From the diethyl ether extract of Artemisia lactiflora, the four terpenoids, including dihydroactinidiolide, megastigmatrienone, alpha-curcumene, and dehydrovomifoliol, were the most intense peaks observed using LC-MS/MS, whereas bis (2-ethylhexyl) phthalate was a contaminant. In a transwell assay, the A. lactiflora diethyl ether extract (32 μg/ml) and dihydroactinidiolide (250 μg/ml) markedly inhibited the migration and invasion of non-small cell lung cancer (NSCLC) cells, similar to the standard anti-metastatic drug (capmatinib). Western blot analysis revealed that mesenchymal N-cadherin is downregulated in NSCLC cells under the treatment conditions. The potential anti-metastatic property of dihydroactinidiolide is promising as a new candidate anti-metastatic agent for lung cancer treatment.

[Tissue specific distribution of terpenoid biosynthesis in Sarcandra glabra based on transcriptome and metabolome analysis]

The leaves and roots of Sarcandra glabra (thunb) nakai have different therapeutic effects in some clinical applications. In order to explore the tissue specific distribution differences of terpenoids in the leaves and roots of S. glabra, and to analyze the molecular mechanism of the formation of their pharmacodynamic quality differences. In this study, liquid chromatography-mass spectrometry (LC-MS) and Illumina HiSeqTM high-throughput sequencing techniques were respectively used to obtain the metabolome and transcriptome data of the leaves and roots of S. glabra. The metabolomics analysis showed that there were 50 differential terpenoids metabolites between the leaves and roots, including farnesylcysteine, d-glyceraldehyde 3-phosphate, and (R)-5-phosphomevalonate. The transcriptomics analysis indicated that there were 57 differentially expressed metabolic enzyme coding genes, including ACTC, HMGCR, MVK, DXS, and KS. Moreover, there were seven transcription factors, including MYB, C2H2, AP2/ERF-ERF, which were predicted to participate in regulating the differences in terpenoid synthesis and accumulation between the leaves and roots of S. glabra. qRT-PCR results demonstrated that the expression changes of eight randomly selected enzyme genes involved in terpene synthesis between the leaves and roots of S. glabra, which were consistent with the transcriptome sequencing results. This study will help to elucidate the molecular mechanisms underlying the clinical efficacy differences between the leaves and roots of S. glabra, and facilitate the extraction, utilization, and resource development of S. glabra.

Plant Extracts and Phytochemicals from the Asteraceae Family with Antiviral Properties

Asteraceae (Compositae), commonly known as the sunflower family, is one of the largest plant families in the world and includes several species with pharmacological properties. In the search for new antiviral candidates, an in vitro screening against dengue virus (DENV) was performed on a series of dichloromethane and methanolic extracts prepared from six Asteraceae species, including Acmella bellidioides, Campuloclinium macrocephalum, Grindelia pulchella, Grindelia chiloensis, Helenium radiatum, and Viguiera tuberosa, along with pure phytochemicals isolated from Asteraceae: mikanolide (1), eupatoriopicrin (2), eupahakonenin B (3), minimolide (4), estafietin (5), 2-oxo-8-deoxyligustrin (6), santhemoidin C (7), euparin (8), jaceidin (9), nepetin (10), jaceosidin (11), eryodictiol (12), eupatorin (13), and 5-demethylsinensetin (14). Results showed that the dichloromethane extracts of C. macrocephalum and H. radiatum and the methanolic extracts prepared from C. macrocephalum and G. pulchella were highly active and selective against DENV-2, affording EC50 values of 0.11, 0.15, 1.80, and 3.85 µg/mL, respectively, and SIs of 171.0, 18.8, >17.36, and 64.9, respectively. From the pool of phytochemicals tested, compounds 6, 7, and 8 stand out as the most active (EC50 = 3.7, 3.1, and 6.8 µM, respectively; SI = 5.9, 6.7, and >73.4, respectively). These results demonstrate that Asteraceae species and their chemical constituents represent valuable sources of new antiviral molecules.

(Celastraceae) against pathogenic bacteria

The pharmacological properties of plant extracts and phytochemicals, such as flavonoids and terpenoids, remain of great interest. In this work, the effect of extracts, friedelan-3,21-dione, and 3β-O-D-glucosyl-sitosterol isolated from Tontelea micrantha roots was evaluated against Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Klebsiella oxytoca and Escherichia coli. The antibacterial activity was evaluated by the minimum inhibitory and bactericidal concentrations (MIC and MBC, respectively), and the synergistic effect was assessed by the Checkerboard assay. Furthermore, the cytotoxicity of the plant-derived compounds against Vero cells was measured by the 3-(4 5-dimethylthiazol-2-yl)-2 5-diphenyltetrazolium bromide (MTT) method. The biological effects of the isolated compounds were predicted using the PASS online software. The chloroform and hexane extracts of T. micrantha roots showed promising antibacterial effect, with MIC in the range of 4.8-78.0 µg/mL. Further analyses showed that these compounds do not affect the integrity of the membrane. The combination with streptomycin strongly reduced the MIC of this antibiotic and extracts. The extracts were highly toxic to Vero cells, and no cytotoxicity was detected for the two terpenoids isolated from them (i.e. friedelan-3,21-dione and 3β-O-D-glucosyl-sitosterol; CC50 > 1000 μg/mL). Therefore, extracts obtained from T. micrantha roots significantly inhibited bacterial growth and are considered promising agents against pathogenic bacteria. The cytotoxicity results were very relevant and can be tested in bioassays.

Terpenoid-Mediated Targeting of STAT3 Signaling in Cancer: An Overview of Preclinical Studies

Cancer has become one of the most multifaceted and widespread illnesses affecting human health, causing substantial mortality at an alarming rate. After cardiovascular problems, the condition has a high occurrence rate and ranks second in terms of mortality. The development of new drugs has been facilitated by increased research and a deeper understanding of the mechanisms behind the emergence and advancement of the disease. Numerous preclinical and clinical studies have repeatedly demonstrated the protective effects of natural terpenoids against a range of malignancies. Numerous potential bioactive terpenoids have been investigated in natural sources for their chemopreventive and chemoprotective properties. In practically all body cells, the signaling molecule referred to as signal transducer and activator of transcription 3 (STAT3) is widely expressed. Numerous studies have demonstrated that STAT3 regulates its downstream target genes, including Bcl-2, Bcl-xL, cyclin D1, c-Myc, and survivin, to promote the growth of cells, differentiation, cell cycle progression, angiogenesis, and immune suppression in addition to chemotherapy resistance. Researchers viewed STAT3 as a primary target for cancer therapy because of its crucial involvement in cancer formation. This therapy primarily focuses on directly and indirectly preventing the expression of STAT3 in tumor cells. By explicitly targeting STAT3 in both in vitro and in vivo settings, it has been possible to explain the protective effect of terpenoids against malignant cells. In this study, we provide a complete overview of STAT3 signal transduction processes, the involvement of STAT3 in carcinogenesis, and mechanisms related to STAT3 persistent activation. The article also thoroughly summarizes the inhibition of STAT3 signaling by certain terpenoid phytochemicals, which have demonstrated strong efficacy in several preclinical cancer models.

Identification of terpenoids as dihydropteroate synthase and dihydrofolate reductase inhibitors through structure-based virtual screening and molecular dynamic simulations

Bacterial infections are rising, and antimicrobial resistance (AMR) in bacteria has worsened the scenario, requiring extensive research to find alternative therapeutic agents. Terpenoids play an essential role in protecting plants from herbivores and pathogens. The present study was designed to focus on in silico evaluation of terpenoids for their affinity towards two necessary enzymes, i.e. DHFR and DHPS, which are involved in forming 5, 6, 7, 8-tetrahydrofolate, a key component in bacterial DNA synthesis proteins. Additionally, to account for activity against resistant bacteria, their affinity towards the L28R mutant of DHFR was also assessed in the study. The structure-based drug design approach was used to screen the compound library of terpenes for their interaction with active sites of DHFR and DHPS. Further, compounds were screened based on their dock score, pharmacokinetic properties, and binding affinities. A total of five compounds for each target protein were screened, having dock scores better than their respective standard drug molecules. CNP0169378 (-8.4 kcal/mol) and CNP0309455 (-6.5 kcal/mol) have been identified as molecules with a higher affinity toward the targets of DHFR and DHPS, respectively. At the same time, one molecule CNP0298407 (-5.8 kcal/mol for DHPS, -7.6 kcal/mol for DHFR, -6.1 kcal/mol for the L28R variant), has affinity for both proteins (6XG5 and 6XG4). All the molecules have good pharmacokinetic properties. We further validated the docking study by binding free energy calculations using the MM/GBSA approach and molecular dynamics simulations.Communicated by Ramaswamy H. Sarma.

Synthesis of Waixenicin A: Exploring Strategies for Nine-Membered Ring Formation

We present a comprehensive account on our efforts behind the recently published synthesis of waixenicin A. Our approach for constructing the dihydropyran ring relied on an Achmatowicz rearrangement. For the assembly of the nine-membered ring, four distinct strategies were investigated. Our initial attempts using radical-based addition/fragmentation reactions targeting the C7-C11 bond proved unsuitable for accessing the 6/9-bicycle. By employing anionic fragmentation conditions at the furfuryl alcohol stage, we successfully reached a 5/9-bicycle. However, subsequent ring-expansion was unsuccessful. Alternative approaches, such as Nozaki-Hiyama-Kishi or Heck reactions to connect the C6-C7 bond, also encountered difficulties, with no nine-membered ring formation observed. Our first breakthrough came from our attempts to install the C5-C6 bond via an intramolecular alkylation. Surprisingly, subsequent functional group modifications proved unexpectedly challenging, necessitating a redesign of our synthetic route. Drawing from all our investigations, we concluded that construction of the C9-C10 bond would enable efficient nine-membered ring alkylation and would facilitate the installation of the desired substitution pattern along the southern periphery. Exploration of this strategy yielded further surprises but ultimately led to the successful synthesis of waixenicin A and 9-deacetoxy-14,15-deepoxyxeniculin. For the latter compound, a bioinspired one-step rearrangement to xeniafauranol A was achieved.

Nano-selenium foliar intervention-induced resistance of cucumber to Botrytis cinerea by activating jasmonic acid biosynthesis and regulating phenolic acid and cucurbitacin

PURPOSE AND METHODS

Botrytis cinerea is the primary disease affecting cucumber production. It can be managed by applying pesticides and cultivating disease-resistant cucumber strains. However, challenges, such as drug resistance in pathogenic bacteria and changes in physiological strains, are obstacles in the effective management of B. cinerea. Nano-selenium (Nano-Se) has potential in enhancing crop resistance to biological stress, but the exact mechanism for boosting disease resistance remains unclear. Here, we used metabolomics and transcriptomics to examine how Nano-Se, as an immune activator, induces plant resistance.

RESULT

Compared with the control group, the application of 10.0 mg/L Nano-Se on the cucumber plant's leaf surface resulted in increased levels of chlorophyll, catalase (10.2%), glutathione (326.6%), glutathione peroxidase (52.2%), cucurbitacin (41.40%), and metabolites associated with the phenylpropane synthesis pathway, as well as the total antioxidant capacity (21.3%). Additionally, the expression levels of jasmonic acid (14.8 times) and related synthetic genes, namely LOX (264.1%), LOX4 (224.1%), and AOC2 (309.2%), were up-regulated. A transcription analysis revealed that the CsaV3_4G002860 gene was up-regulated in the KEGG enrichment pathway in response to B. cinerea infection following the 10.0 mg/L Nano-Se treatment.

DISCUSSION

In conclusion, the activation of the phenylpropane biosynthesis and branched-chain fatty acid pathways by Nano-Se promotes the accumulation of jasmonic acid and cucurbitacin in cucumber plants. This enhancement enables the plants to exhibit resistance against B. cinerea infections. Additionally, this study identified a potential candidate gene for cucumber resistance to B. cinerea induced by Nano-Se, thereby laying a theoretical foundation for further research in this area. © 2023 Society of Chemical Industry.

Solid-State Microwave Drying for Medical Cannabis Inflorescences: A Rapid and Controlled Alternative to Traditional Drying

Introduction: As the medical use of Cannabis is evolving there is a greater demand for high-quality products for patients. One of the main steps in the manufacturing process of medical Cannabis is drying. Most current drying methods in the Cannabis industry are relatively slow and inefficient processes. Materials and Methods: This article presents a drying method based on solid-state microwave (MW) that provides fast and uniform drying, and examines its efficiency for drying Cannabis inflorescences compared with the traditional drying method. We assessed 67 cannabinoids and 36 terpenoids in the plant in a range of drying temperatures (40°C, 50°C, 60°C, and 80°C). The identification and quantification of these secondary metabolites were done by chromatography methods. Results: This method resulted in a considerable reduction of drying time, from several days to a few hours. The multiple frequency-phase combination states of the system allowed control and prediction of moisture levels during drying, thus preventing overdrying. A drying temperature of 50°C provided the most effective results in terms of both short drying time and preservation of the composition of the secondary metabolites compared with traditional drying. At 50°C, the chemical profile of phytocannabinoids and terpenoids was best kept to that of the original plant before drying, suggesting less degradation by chemical reactions such as decarboxylation. The fast-drying time also reduced the susceptibility of the plant to microbial contamination. Conclusion: Our results support solid-state MW drying as an effective postharvest step to quickly dry the plant material for improved downstream processing with a minimal negative impact on product quality.

with neuroprotective activity

Two new terpenoids were isolated from the branches and leaves of Rhododendron dauricum L., named as rhodayritions A (1) and B (2), together with five known compounds which were identified litseachromolaevane A (3), 11-αH-dihydrodehydrocostus lactone (4), (+)-9β-hydroxyeudesma-4,11(13)-dien-12-al (5), macrostachyoside B (6) and aglaiabbreviatin E (7), respectively. The structures of isolated compounds were determined by UV, HR-ESI-MS, NMR analysis and X-Ray. Their neuroprotective activity was studied on serum deprivation-induced PC12 cells by the MTT method, compounds 1, 6, and 7 exhibited significant neuroprotective activity at 20 μΜ.

Insights into How Plant-Derived Extracts and Compounds Can Help in the Prevention and Treatment of Keloid Disease: Established and Emerging Therapeutic Targets

Keloid is a disease in which fibroblasts abnormally proliferate and synthesize excessive amounts of extracellular matrix, including collagen and fibronectin, during the healing process of skin wounds, causing larger scars that exceed the boundaries of the original wound. Currently, surgical excision, cryotherapy, radiation, laser treatment, photodynamic therapy, pressure therapy, silicone gel sheeting, and pharmacotherapy are used alone or in combinations to treat this disease, but the outcomes are usually unsatisfactory. The purpose of this review is to examine whether natural products can help treat keloid disease. I introduce well-established therapeutic targets for this disease and various other emerging therapeutic targets that have been proposed based on the phenotypic difference between keloid-derived fibroblasts (KFs) and normal epidermal fibroblasts (NFs). We then present recent studies on the biological effects of various plant-derived extracts and compounds on KFs and NFs. Associated ex vivo, in vivo, and clinical studies are also presented. Finally, we discuss the mechanisms of action of the plant-derived extracts and compounds, the pros and cons, and the future tasks for natural product-based therapy for keloid disease, as compared with existing other therapies. Extracts of Astragalus membranaceus, Salvia miltiorrhiza, Aneilema keisak, Galla Chinensis, Lycium chinense, Physalis angulate, Allium sepa, and Camellia sinensis appear to modulate cell proliferation, migration, and/or extracellular matrix (ECM) production in KFs, supporting their therapeutic potential. Various phenolic compounds, terpenoids, alkaloids, and other plant-derived compounds could modulate different cell signaling pathways associated with the pathogenesis of keloids. For now, many studies are limited to in vitro experiments; additional research and development are needed to proceed to clinical trials. Many emerging therapeutic targets could accelerate the discovery of plant-derived substances for the prevention and treatment of keloid disease. I hope that this review will bridge past, present, and future research on this subject and provide insight into new therapeutic targets and pharmaceuticals, aiming for effective keloid treatment.

Influence of Additional White, Red and Far-Red Light on Growth, Secondary Metabolites and Expression of Hormone Signaling Genes in Scots Pine under Sunlight

The influence of short-term additional white (WL), red (RL) and far-red (FRL) light and combined RL+FRL on the physiological morphological and molecular characteristics of two-year-old Scots pine plants grown in a greenhouse under sunlight was studied. Additional RL and RL+FRL increased the number of xylem cells, transpiration and the expression of a group of genes responsible for the biosynthesis and signaling of auxins (AUX/IAA, ARF3/4, and ARF16) and brassinosteroids (BR-α-RED and BRZ2), while the expression of genes related to the signaling pathway related to jasmonic acid was reduced. Additionally, WL, RL and RL+FRL increased the content of proanthocyanidins and catechins in young needles; however, an increase in the expression of the chalcone synthase gene (CHS) was found under RL, especially under RL+FRL, which possibly indicates a greater influence of light intensity than observed in the spectrum. Additional WL increased photosynthetic activity, presumably by increasing the proportion and intensity of blue light; at the same time, the highest transpiration index was found under RL. The results obtained indicate that the combined effect of additional RL+FRL can accelerate the development of pine plants by increasing the number of xylem cells and increasing the number of aboveground parts but not the photosynthetic activity or the accumulation of secondary metabolites.

Two new sesquiterpene glycosides from the stems of Dendrobium henanense and their anti-inflammatory activity

Two new sesquiterpene glycosides, 8α,12,15β-trihydroxycopacamphan-15-O-β-D-glucopyranoside (1) and dendrobiumane C-11-O-β-D-glucopyranoside (2), along with three known terpenoids (3-5) were isolated from the aerial stems of Dendrobium henanense. Their structures were elucidated based on NMR-spectroscopic and HR-MS analyses. All compounds could reduce the levels of NO, TNF-α and IL-1β in LPS-induced RAW264.7 cells with IC50 values ranging from 10.37 to 34.55 µΜ.

Integrated metabolomic and transcriptomic analyses revealed metabolite variations and regulatory networks in Cinnamomum cassia Presl from four growth years

To understand the mechanism of the dynamic accumulation of active ingredients in Cinnamomum cassia Presl, metabolomic and transcriptomic analyses of 5~8 years old C. cassia were performed. A total of 72 phenylpropanoids, 146 flavonoids, and 130 terpenoids showed marked changes. Most phenylpropanoids and flavonoids showed markedly higher abundances in 6-year-old C. cassia than in others, which was related to the higher expression of genes that synthesize and regulate phenylpropanoids and flavonoid. We identified transcription factors (TFs) and genes involved in phenylpropanoids and flavonoids synthesis and regulation through co-expression network analyses. Furthermore, most of the terpenoids in 5-year-old C. cassia showed markedly higher abundances than in others, which was due to the differentially expressed genes upstream of the terpenoids pathway. The results of our study provide new insights into the synthesis and accumulation of phenylpropanoid, flavonoids and terpenoids in C. cassia at four growth stages.

Anti-Inflammatory Terpenoids from the Rhizomes of Shell Ginger

Shell ginger (Alpinia zerumbet) is a perennial ornamental plant of ginger native to East Asia, which can be used as a flavoring agent in food or beverage, as well as a traditional Chinese medicine. In this study, a total of 37 terpenoids, including 7 new compounds, zerumin D1 to zerumin D7 (2, 3, 28-30, 36, and 37), and 5 new naturally occurring compounds, zerumin D10 to zerumin D14 (9, 12, 15, 20, and 24), were isolated and identified from the rhizomes of shell ginger. Compound 3 was an unprecedented variant labdane diterpenoid featuring a unique 6/7/6/3 tetracyclic cyclic ether system in its side chain. The anti-inflammatory activities of the isolated terpenoids were assessed in RAW 264.7 macrophages stimulated by lipopolysaccharide (LPS). Compound 4 significantly inhibited the production of nitric oxide with an IC50 value of 5.4 μM. Further investigation revealed that compounds 2 and 3 may inhibit the nuclear translocation of NF-κB, thus suppressing the expression of IL-6, IL-1β, iNOS, and COX-2 to exert the anti-inflammatory effects.

In silico evaluation of some commercially available terpenoids as spike glycoprotein of SARS-CoV-2 - inhibitors using molecular dynamic approach

Coronavirus, an extremely contagious infections disease had a harmful effect on the world's population. It is a family of enveloped, single-stranded, positive-strand RNA viruses of Nidovirales order belongs to coroviridae family. At present, worldwide several lakhs of deaths and several billions of infections have been reported. Hence, the focus of the present study was to assess the SARS-CoV-2 enzyme inhibitory potential of certain commercially available terpenoids using Lamarckian genetic algorithm as a working principle and molecular dynamic studies was also performed. AutoDock 4.2 software was used to perform the computational docking calculations of terpenoids against SARS-CoV-2 enzyme. The terpenoids such as, Andrographolide, Betulonic acid, Erythrodiol, Friedelin, Mimuscopic acid, Moronic acid, and Retinol were selected based on the drug likeness properties. Remdesivir a well-known anti-viral drug was selected as the standard drug. Molecular dynamic simulation studies were carried using Desmond module of Schrodinger Suite. In the current study we observed that, Friedelin was exhibited excellent SARS-CoV-2 enzyme inhibitory potential than the standard drug and other selected terpenoids. Friedelin and the standard Remdesivir was undergone the molecular dynamic studies and Friedelin showed a good number of hydrogen bonds over the simulation time of 100 ns. Based on the in silico computational evaluation, it can be concluded that Friedelin could be worthwhile terpenoid against SARS-CoV-2 spike protein. A further study on Friedelin is required to develop a potential chemical entity against the management of COVID disease.Communicated by Ramaswamy H. Sarma.

Terpenoids in Diabetic Nephropathy: Advances and Therapeutic Opportunities

Diabetic nephropathy (DN) is the foremost ailment resulting in end-stage renal damage. Chronic hyperglycaemia and hyperlipidaemia are the foremost reason for disease progression. The disease is characterized by the severity of albuminuria and cardiovascular disorders. Approximately 20 to 40% of the global prevalence of DN is mostly reported to occur in individuals with diabetes, and nearly 28% of DN occurs in individuals with other renal disorders. The pathological mechanism is very complex, involving innumerable targets and leading to multiple pharmacological effects. Thus, the scientific community is forced to work in search of safe and potent therapeutics that can tackle the complex pathology of DN effectively. The secondary plant metabolites categorized as terpenoids gained attention as potential therapeutics contrary to others for the management of diabetic nephropathy and other associated syndromes by their strong antioxidant activity and inhibition of advanced glycation and its associated products. This review focused on herbal therapeutics for the management of diabetic nephropathy. Moreover, different types of terpenoids, their biological sources, and proposed mechanisms of action are explored for the development of a novel pharmacophore for diabetic nephropathy.

Stomatal closure prevents xylem transport of green leaf volatiles and impairs their systemic function in plants

Plants perceive environmental stresses as whole organisms via distant signals conveying danger messages through their vasculature. In parallel to vascular transport, airborne plant volatile compounds, including green leaf volatiles (GLVs), can bypass the lack of vascular connection. However, some small volatile compounds move through the vasculature; such vascular transport is little known about GLVs. Here we illustrate GLV alcohols as solutes move within xylem vessels in Zea mays. We describe GLV alcohols, including Z-3-hexen-ol and its isomer E-3-hexen-ol, which is not synthesized in maize, moving through the transpiration stream via xylem vessels. Since transpiration is mediated by the stomatal aperture, closing stomata by two independent methods diminishes the transport of GLV alcohol and its isomer. In addition, the lower transport of GLV alcohols impairs their function in inducing terpenoid biosynthesis, suggesting that xylem transport of GLV alcohols plays a significant role in their systemic function. Our study suggests that GLV alcohols, in addition to airborne signals, are transported through xylem vessels. Our findings can be critical in future studies about the perception and function of these compounds in plants.

Structure-based Virtual Screening and Molecular Dynamic Simulation Approach for the Identification of Terpenoids as Potential DPP-4 Inhibitors

BACKGROUND

Diabetes mellitus is a metabolic disorder where insulin secretion is compromised, leading to hyperglycemia. DPP-4 is a viable and safer target for type 2 diabetes mellitus. Computational tools have proven to be an asset in the process of drug discovery.

OBJECTIVE

In the present study, tools like structure-based virtual screening, MM/GBSA, and pharmacokinetic parameters were used to identify natural terpenoids as potential DPP-4 inhibitors for treating diabetes mellitus.

METHODS

Structure-based virtual screening, a cumulative mode of elimination technique, was adopted, identifying the top five potent hit compounds depending on the docking score and nonbonding interactions.

RESULTS

According to the docking data, the most important contributors to complex stability are hydrogen bonding, hydrophobic interactions, and Pi-Pi stacking interactions. The dock scores ranged from -6.492 to -5.484 kcal/mol, indicating robust ligand-protein interactions. The pharmacokinetic characteristics of top-scoring hits (CNP0309455, CNP0196061, CNP0122006, CNP0 221869, CNP0297378) were also computed in this study, confirming their safe administration in the human body. Also, based on the synthetic accessibility score, all top-scored hits are easily synthesizable. Compound CNP0309455 was quite stable during molecular dynamic simulation studies.

CONCLUSION

Virtual database screening yielded new leads for developing DPP-4 inhibitors. As a result, the findings of this study can be used to design and develop natural terpenoids as DPP-4 inhibitors for the medication of diabetes mellitus.

Comparative analysis of sorghum (C4) and rice (C3) plant headspace volatiles induced by artificial herbivory

Acute stress responses include release of defensive volatiles from herbivore-attacked plants. Here we used two closely related monocot species, rice as a representative C3 plant, and sorghum as a representative C4 plant, and compared their basal and stress-induced headspace volatile organic compounds (VOCs). Although both plants emitted similar types of constitutive and induced VOCs, in agreement with the close phylogenetic relationship of the species, several mono- and sesquiterpenes have been significantly less abundant in headspace of sorghum relative to rice. Furthermore, in spite of generally lower VOC levels, some compounds, such as the green leaf volatile (Z)-3-hexenyl acetate and homoterpene DMNT, remained relatively high in the sorghum headspace, suggesting that a separate mechanism for dispersal of these compounds may have evolved in this plant. Finally, a variable amount of several VOCs among three sorghum cultivars of different geographical origins suggested that release of VOCs could be used as a valuable resource for the increase of sorghum resistance against herbivores.

Evaluation of Salicylic Acid and Methyl Jasmonate as Elicitors in Phyllanthus acuminatus Hairy Roots by Non-Targeted Analysis Using High-Resolution Mass Spectrometry

Phyllanthus acuminatus has been studied for its vast medical and industrial potential. Phytochemical investigations reveal that the genus is a rich source of lignans, flavonoids, phenolics, terpenoids, and other metabolites. However, the phytochemical profile elucidation of this species still needs further research. The use of eliciting compounds such as salicylic acid and methyl jasmonate has managed to increase the production of secondary metabolites in plant cell cultures. Hairy roots of Phyllanthus acuminatus were produced in 250 mL flasks with a 16 h light/8 h darkness photoperiod under diffused light with a culture time of four weeks. The elicitors salicylic acid and methyl jasmonate were tested in 50 μM and 200 μM concentrations. Non-targeted analysis was done for the different treatments using HR-MS. Identified metabolites were grouped in phenylpropanoids, phenols, and mucic acids, and statistical analysis of relative concentrations was achieved. A significant change in phenols' relative concentrations appeared in the elicitations with salicylic acid. Because of the elicitation treatment, specific compounds increased their concentrations, some of which have known pharmacological effects and are used in treating chronic diseases. The best elicitation treatment was salicylic acid 50 μM as it increased by more than 100% the general content of phenols and phenylpropanoid derivates and triplicates the concentration of mucic acid derivates in treated hairy root extracts. The application of non-targeted analysis showed interesting changes in phytochemical concentration due to elicitation in Phyllanthus acuminatus hairy roots.

Terpene-Functionalized Fluoroquinolones as Potential Antimicrobials: Synthesis and Properties

This study was the first to synthesize terpene-containing conjugates of fluoroquinolones, ciprofloxacin and norfloxacin, and to evaluate their antibacterial activity against gram-positive methicillin sensitive (MSSA) and methicillin resistant (MRSA) S. aureus, gram-negative P. aeruginosa as well as antifungal activity against C. albicans. The ability of obtained fluoroquinolones to inhibit S. aureus growth was found to depend upon the presence of a linker separating the bulky terpene and fluoroquinolone fragments, and this activity diminished with increasing its length. The highest activity against MSSA was demonstrated by ciprofloxacin derivatives with campholenic (MIC 1 μg/mL) and 2-(isobornan-2-yl-sulfanyl)acetyl (MIC 0.5 μg/mL) substituents. The compound with the last fragment showed high activity against MRSA (MIC 8 μg/mL). The terpene-functionalized norfloxacin derivatives generally proved to be less active than those containing ciprofloxacin fragment. Camphor-10-sulfonylamide derivative with the ciprofloxacin fragment was the only one of all compounds that showed high antifungal activity against C. albicans (8 μg/mL). The study presents data on docking fluoroquinolones to S. aureus DNA gyrase to explain the reasons for manifestation or disappearance of antibacterial activity. The cytotoxicity of fluoroquinolones that showed any antimicrobial activity was investigated against bovine primary lung cells, and they were found to be not toxic in most cases.

Determination of Volatile Organic Compounds and Endogenous Extracts and Study of Expression Patterns of TPS and BSMT in the Flowers of Seven Lilium Cultivars

Lily is one of the most important cut flowers in the world, with a rich floral fragrance. To further explore the fragrance emission mechanisms of lily cultivars, headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and organic solvent extraction-gas chromatography-mass spectrometry (OSE-GC-MS) were used to unveil the volatile organic compounds (VOCs) and endogenous extracts of seven lily cultivars. Furthermore, real-time quantitative PCR (qRT-PCR) was used to determine the expression levels of two key genes (TPS and BSMT) related to the biosynthesis of monoterpenoids and methyl benzoate. The results show that forty-five VOCs were detected in the petals of seven lily cultivars, and the main compounds were monoterpenoids and phenylpropanoids/benzenoids. Dichloromethane was the best solvent for extracting the endogenous extracts of Lilium 'Viviana' petals and eighteen endogenous extracts were detected using dichloromethane to extract the petals of seven lily cultivars. Each compound's emission ratio (natural logarithm of the ratio of VOC content to endogenous extract content) was calculated, and linear regression analyses between emission ratios and boiling points were conducted. Significant linear negative correlations existed between the emission ratios and boiling points of compounds, and the regression equations' coefficients of determination (R2) were all greater than 0.7. TPS was expressed highly in 'Viviana', 'Pink News', and 'Palazzo', and BSMT was expressed highly in 'Pink News' and 'Palazzo'. Correlation analyses between the gene expression levels and the monoterpenoids and methyl benzoate contents found that the TPS expression levels have strong positive correlations with monoterpenoids content, while no correlations were found between the expression levels of BSMT and the contents of methyl benzoate. This study lays the foundation for research on the release patterns of VOCs in the flowers of Lilium, and the breeding of lilies for their floral fragrance.

A Case of Convergent Evolution: The Bacterial Sesquiterpene Synthase for 1-epi-Cubenol from Nonomuraea coxensis

A terpene synthase from Nonomuraea coxensis was identified as (+)-1-epi-cubenol synthase. The enzyme is phylogenetically unrelated to the known enzyme of the same function that is widespread in streptomycetes. Isotopic labelling experiments were performed to unambiguously assign the NMR data and to investigate hydrogen migrations during terpene cyclisations. Epoxidations of (+)-1-epi-cubenol and of the plant derived compounds (-)-cubenol and (-)-1-epi-cubenol confirmed the structure of a natural product isolated from the brown alga Dictyopteris divaricata and allowed to conclude on its absolute configuration. The crystal structures of the epoxides from (+)- and (-)-1-epi-cubenol and the acid catalysed conversion into an isomeric ketone are reported.

Crithmum maritimum L. Volatile Compound's Diversity Through Tunisian Populations: Use of a Plant Organ-Based Statistical Approach for Chemotype Identification

This work aimed to investigate the variability of the chemical composition of the aromatic halophyte Crithmum maritimum L. essential oils according to the geographical origin and separated organs, using a statistical approach based on the multiple analysis of variance and the Principal Component Analyses. One hundred twenty samples were collected from three distinct bioclimatic regions (10 samples×3 provenances×4 organs). Hydrodistillation of separated organs (roots, stems, leaves and flowers) yielded 0.13 to 1.75 % of the dry matter. Chemical investigation of the volatile compounds by Gas chromatography-mass spectrometry showed that C. maritimum essential oils were dominated by monoterpenes hydrocarbons, oxygenated monoterpenes, and phenylpropanoids varying, respectively, from 33.3 to 66.9, from 7.8 to 46.6 and from 4.5 to 57.2 % according to organs and localities. Statistical analyses identified three different chemotypes depending on the geographic origin as follow: γ-Terpinene-Thymol methyl ether / Dillapiole / Thymol methyl ether-Dillapiole.

A terpene synthase supergene locus determines chemotype in Melaleuca alternifolia (tea tree)

Leaf oil terpenes vary categorically in many plant populations, leading to discrete phenotypes of adaptive and economic significance, but for most species, a genetic explanation for the concerted fluctuation in terpene chemistry remains unresolved. To uncover the genetic architecture underlying multi-component terpene chemotypes in Melaleuca alternifolia (tea tree), a genome-wide association study was undertaken for 148 individuals representing all six recognised chemotypes. A number of single nucleotide polymorphisms in a genomic region of c. 400 kb explained large proportions of the variation in key monoterpenes of tea tree oil. The region contained a cluster of 10 monoterpene synthase genes, including four genes predicted to encode synthases for 1,8-cineole, terpinolene, and the terpinen-4-ol precursor, sabinene hydrate. Chemotype-dependent null alleles at some sites suggested structural variants within this gene cluster, providing a possible basis for linkage disequilibrium in this region. Genotyping in a separate domesticated population revealed that all alleles surrounding this gene cluster were fixed after artificial selection for a single chemotype. These observations indicate that a supergene accounts for chemotypes in M. alternifolia. A genetic model with three haplotypes, encompassing the four characterised monoterpene synthase genes, explained the six terpene chemotypes, and was consistent with available biparental cross-segregation data.

The Integration of the Metabolome and Transcriptome for Dendrobium nobile Lindl. in Response to Methyl Jasmonate

Dendrobium nobile Lindl., as an endangered medicinal plant within the genus Dendrobium, is widely distributed in southwestern China and has important ecological and economic value. There are a variety of metabolites with pharmacological activity in D. nobile. The alkaloids and polysaccharides contained within D. nobile are very important active components, which mainly have antiviral, anti-tumor, and immunity improvement effects. However, the changes in the compounds and functional genes of D. nobile induced by methyl jasmonate (MeJA) are not clearly understood. In this study, the metabolome and transcriptome of D. nobile were analyzed after exposure to MeJA. A total of 377 differential metabolites were obtained through data analysis, of which 15 were related to polysaccharide pathways and 35 were related to terpenoids and alkaloids pathways. Additionally, the transcriptome sequencing results identified 3256 differentially expressed genes that were discovered in 11 groups. Compared with the control group, 1346 unigenes were differentially expressed in the samples treated with MeJA for 14 days (TF14). Moreover, the expression levels of differentially expressed genes were also significant at different growth and development stages. According to GO and KEGG annotations, 189 and 99 candidate genes were identified as being involved in terpenoid biosynthesis and polysaccharide biosynthesis, respectively. In addition, the co-expression analysis indicated that 238 and 313 transcription factors (TFs) may contribute to the regulation of terpenoid and polysaccharide biosynthesis, respectively. Through a heat map analysis, fourteen terpenoid synthetase genes, twenty-three cytochrome P450 oxidase genes, eight methyltransferase genes, and six aminotransferase genes were identified that may be related to dendrobine biosynthesis. Among them, one sesquiterpene synthase gene was found to be highly expressed after the treatment with MeJA and was positively correlated with the content of dendrobine. This study provides important and valuable metabolomics and transcriptomic information for the further understanding of D. nobile at the metabolic and molecular levels and provides candidate genes and possible intermediate compounds for the dendrobine biosynthesis pathway, which lays a certain foundation for further research on and application of Dendrobium.

Functions of Representative Terpenoids and Their Biosynthesis Mechanisms in Medicinal Plants

Terpenoids are the broadest and richest group of chemicals obtained from plants. These plant-derived terpenoids have been extensively utilized in various industries, including food and pharmaceuticals. Several specific terpenoids have been identified and isolated from medicinal plants, emphasizing the diversity of biosynthesis and specific functionality of terpenoids. With advances in the technology of sequencing, the genomes of certain important medicinal plants have been assembled. This has improved our knowledge of the biosynthesis and regulatory molecular functions of terpenoids with medicinal functions. In this review, we introduce several notable medicinal plants that produce distinct terpenoids (e.g., Cannabis sativa, Artemisia annua, Salvia miltiorrhiza, Ginkgo biloba, and Taxus media). We summarize the specialized roles of these terpenoids in plant-environment interactions as well as their significance in the pharmaceutical and food industries. Additionally, we highlight recent findings in the fields of molecular regulation mechanisms involved in these distinct terpenoids biosynthesis, and propose future opportunities in terpenoid research, including biology seeding, and genetic engineering in medicinal plants.

Interesting Behavior of Geranic Acid during the Beer Brewing Process: Why Could Geranic Acid Remain at a Higher Level Only in the Beer Using Sorachi Ace Hops?

Hops are among the most important ingredients in beer that contribute to beer flavor. Consequently, novel types of hops have been bred and widely used worldwide. For example, the Sorachi Ace hop imparts characteristic varietal aromas, including woody, pine-like, citrus, dill-like, and lemongrass-like aromas, to the finished beer. In our previous study, the unique volatile compound geranic acid was significantly detected only in the test beer brewed with the Sorachi Ace hop; moreover, the coexistence of geranic acid and other hop-derived flavor compounds could result in the characteristic aroma of the Sorachi Ace beers. In this study, selected hop-derived flavor compounds, including geranic acid, were compared among 17 hop varieties. The geranic acid content in the Sorachi Ace hop was the highest among the studied hops. We also investigated the behavior of geranic acid and related flavor compounds throughout the fermentation process. The content of geranic acid was higher than those of the other compounds during fermentation. Next, we compared the concentrations of these compounds in kettle-, late-, and dry-hopped beers using Sorachi Ace hop. The results revealed that geranic acid remained at higher concentrations from the worts to finished beers despite the decrease in the content of other hop-derived flavor compounds as a result of evaporation and/or other factors during brewing. Further, geranic acid could remain at high levels in the test-brewed beers with Sorachi Ace hops because of its behavior as an acid throughout the brewing process, including during wort boiling and fermentation.

Azadiradione, a Component of Neem Oil, Behaves as a Superoxide Dismutase Mimic When Scavenging the Superoxide Radical, as Shown Using DFT and Hydrodynamic Voltammetry

The neem tree, Azadirachta indica, belongs to the Meliaceae family, and its use in the treatment of medical disorders from ancient times to the present in the traditional medical practices of Asia, Africa and the Middle East is well-documented. Neem oil, extracted from the seeds of the fruit, is widely used, with promising medicinal benefits. Azadiradione, a principal antioxidant component of the seeds of A. indica, is known to reduce oxidative stress and has anti-inflammatory effects. To directly measure the antioxidant ability of neem oil, we used Rotating Ring Disk Electrode (RRDE) hydrodynamic voltammetry to quantify how it can scavenge superoxide radical anions. The results of these experiments show that neem oil is approximately 26 times stronger than other natural products, such as olive oil, propolis and black seed oil, which were previously measured using this method. Next, computational Density Functional Theory (DFT) methods were used to arrive at a mechanism for the scavenging of superoxide radical anions with azadiradione. Our work indicates that azadiradione is an effective antioxidant and, according to our DFT study, its scavenging of the superoxide radical anion occurs through a reaction mechanism in which azadiradione mimics the antioxidant action of superoxide dismutase (SOD). In this mechanism, analogous to the SOD enzymatic reaction, azadiradione is regenerated, along with the production of two products: hydrogen peroxide and molecular oxygen. This antioxidant process provides an explanation for azadiradione's more general and protective biochemical effects.

A Critical Appraisal of the Most Recent Investigations on Ora-Pro-Nobis (Pereskia sp.): Economical, Botanical, Phytochemical, Nutritional, and Ethnopharmacological Aspects

Pereskia aculeata Miller and Pereskia grandfolia Haw, known as 'ora-pro-nobis', are unconventional vegetables belonging to the Cactaceae family, native to the Americas and common in the northeast and southeast regions of Brazil. This review attempts to present a balanced account of both the methods used for obtaining extracts from the diverse parts of the plants and the results that were obtained in terms of their applicability to foods and other products with biological activities. Attention will also be devoted to the properties of their bioactives and their applications to real food products. Methods for obtaining extracts from the diverse parts of the plants will be analyzed, as well as the chemical nature of the bioactives that were hitherto identified. Next, the applicability of ora-pro-nobis in either its integral form or in the form of extracts or other products (mucilages) to the production of food and dietary supplements will be analyzed. The species have been extensively investigated during the last few decades. But, the determination of chemical structures is frequently incomplete and there is a need for new studies on texture determination and color evaluation. Further studies exploring the fruit and flowers of P. aculeata are also required.

Terpenoids as Human Neutrophil Elastase (HNE) Inhibitors: A Comprehensive Review of Natural Anti-inflammatory Isoprenoids

Human neutrophil elastase (HNE) is an enzyme that plays a key role in the body's inflammatory response. It has been linked to several diseases such as chronic obstructive pulmonary disease (COPD), emphysema, and cystic fibrosis. As potential treatments for these diseases, HNE inhibitors are of great interest. Metabolites derived from plants, particularly terpenoids such as β-caryophyllene found in black pepper and other plants, and geraniol present in several essential oils, are recognized as significant sources of inhibitors for HNE. Because of their ability to inhibit HNE, terpenoids are considered promising candidates for developing novel therapies to treat inflammatory conditions such as COPD and emphysema. Furthermore, nature can serve as an excellent designer, and it may offer a safer drug candidate for inhibiting HNE production and activity in the future. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were searched to get relevant and up-to-date literature on terpenoids as human neutrophil elastase inhibitors. This review focuses on the isolation, chemical diversity, and inhibition of human neutrophil elastase (HNE) of various terpenoids reported from natural sources up to 2022. A total of 251 compounds from various terpenoids classes have been reported. Further, it also provides a summary of HNE inhibitors and includes a thorough discussion on the structure-activity relationship.

Characterization of the Chemopreventive Properties of Cannabis sativa L. Inflorescences from Monoecious Cultivars Grown in Central Italy

Hemp bioproducts hold great promise as valuable materials for nutraceutical and pharmaceutical applications due to their diverse bioactive compounds and potential health benefits. In line with this interest and in an attempt to valorize the Lazio Region crops, this present study investigated chemically characterized hydroalcoholic and organic extracts, obtained from the inflorescences of locally cultivated Felina 32, USO 31, Ferimon and Fedora 17 hemp varieties. In order to highlight the possible chemopreventive power of the tested samples, a bioactivity screening was performed, which included studying the antimutagenic activity, radical scavenging power, cytotoxicity in human hepatoma HepG2 cells, leakage of lactate dehydrogenase (LDH) and modulation of the oxidative stress parameters and glucose-6-phosphate dehydrogenase (G6PDH) involved in the regulation of the cell transformation and cancer proliferation. Tolerability studies in noncancerous H69 cholangiocytes were performed, too. The organic extracts showed moderate to strong antimutagenic activities and a marked cytotoxicity in the HepG2 cells, associated with an increased oxidative stress and LDH release, and to a G6PDH modulation. The hydroalcoholic extracts mainly exhibited radical scavenging properties with weak or null activities in the other assays. The extracts were usually well-tolerated in H69 cells, except for the highest concentrations which impaired cell viability, likely due to an increased oxidative stress. The obtained results suggest a possibility in the inflorescences from the Felina 32, USO 31, Ferimon and Fedora 17 hemp varieties as source of bioactive compounds endowed with genoprotective and chemopreventive properties that could be harnessed as preventive or adjuvant healing strategies.

Extracellular matrix turnover: phytochemicals target and modulate the dual role of matrix metalloproteinases (MMPs) in liver fibrosis

Extracellular matrix (ECM) resolution by matrix metalloproteinases (MMPs) is a well-documented mechanism. MMPs play a dual and complex role in modulating ECM degradation at different stages of liver fibrosis, depending on the timing and levels of their expression. Increased MMP-1 combats disease progression by cleaving the fibrillar ECM. Activated hepatic stellate cells (HSCs) increase expression of MMP-2, -9, and -13 in different chemicals-induced animal models, which may alleviate or worsen disease progression based on animal models and the stage of liver fibrosis. In the early stage, elevated expression of certain MMPs may damage surrounding tissue and activate HSCs, promoting fibrosis progression. At the later stage, downregulation of MMPs can facilitate ECM accumulation and disease progression. A number of phytochemicals modulate MMP activity and ECM turnover, alleviating disease progression. However, the effects of phytochemicals on the expression of different MMPs are variable and may depend on the disease models and stage, and the dosage, timing and duration of phytochemicals used in each study. Here, we review the most recent advances in the role of MMPs in the effects of phytochemicals on liver fibrogenesis, which indicates that further studies are warranted to confirm and define the potential clinical efficacy of these phytochemicals.

Genomic and Transcriptomic Analyses Illuminates Unique Traits of Elusive Night Flowering Jasmine Parijat (Nyctanthes arbor-tristis)

The night-flowering Jasmine, Nyctanthes arbor-tristis also known as Parijat, is a perennial woody shrub belonging to the family of Oleaceae. It is popular for its fragrant flowers that bloom in the night and is a potent source of secondary metabolites. However, knowledge about its genome and the expression of genes regulating flowering or secondary metabolite accumulation is lacking. In this study, we generated whole genome sequencing data to assemble the first de novo assembly of Parijat and use it for comparative genomics and demographic history reconstruction. The temporal dynamics of effective population size (Ne ) experienced a positive influence of colder climates suggesting the switch to night flowering may have provided an evolutionary advantage. We employed multi-tissue transcriptome sequencing of floral stages/parts to obtain insights into the transcriptional regulation of nocturnal flower development and the production of volatiles/metabolites. Tissue-specific transcripts for mature flowers revealed key players in circadian regulation and flower development, including the auxin pathway and cell wall modifying genes. Furthermore, we identified tissue-specific transcripts responsible for producing numerous secondary metabolites, mainly terpenoids and carotenoids. The diversity and specificity of Terpene Synthase (TPS) and CCDs (Carotenoid Cleavage Deoxygenases) mediate the bio-synthesis of specialised metabolites in Parijat. Our study establishes Parijat as a novel non-model species to understand the molecular mechanisms of nocturnal blooming and secondary metabolite production.

Unravelling the Secrets of α-Pyrones from Aspergillus Fungi: A Comprehensive Review of Their Natural Sources, Biosynthesis, and Biological Activities

Aspergillus, one of the most product-rich and genetically robust genera, contains a diverse range of species with potential economic and ecological implications. Chemically, Aspergillus is one of the essential sources of polyketides, alkaloids, diphenyl ethers, diketopiperazines, and other miscellaneous compounds, displaying a variety of pharmacological activities. The α-pyrones are unsaturated six-membered lactones. Although α-pyrone has a small structure, it is responsible for the structural diversity of several natural and synthetic compounds and multiple biological activities. In this review, we have summarized approximately 178 α-pyrone containing metabolites derivatives identified/reported from terrestrial, marine, endophytic, and filamentous Aspergillus species, including their sources, biological properties, and biosynthetic pathways until mid-2023, for the first time. This review is the first to compile and analyze the available data on α-pyrone metabolites from Aspergillus, which could facilitate further research and innovation in this field. Additionally, it offers a valuable source of scaffolds for future bioactive drug development, as some of these metabolites have shown potent antimicrobial, anti-inflammatory, and anticancer effects. Therefore, this review has significant implications for the advancement of natural product chemistry, pharmacology, biotechnology, and medicine.

Investigation of Anticholinesterase Activity of Chemically Characterised Hieracium s. str. Methanol Extracts and Their Selected Metabolites

The composition and anticholinesterase activity of the dried MeOH extracts of Hieracium scheppigianum and H. naegelianum underground parts (rhizomes and roots), as well as the anticholinesterase activity of the dried, previously chemically characterised MeOH extracts of the flowering aerial parts of these two and 26 other Hieracium species in the strict sense (s. str.), were investigated. Furthermore, the anticholinesterase activity of 12 selected secondary metabolites of these extracts was evaluated. Using semi-preparative LC-MS, five caffeoylquinic acids and the sesquiterpene lactone crepiside E were isolated from H. scheppigianum underground parts extract. All these compounds were also identified in the underground parts extract of H. naegelianum. Quantitative LC-MS analysis showed that the analysed underground parts extracts were rich in both caffeoylquinic acids (139.77 and 156.62 mg/g of extract, respectively) and crepiside E (126.88 and 116.58 mg/g). In the Ellman method, the tested extracts showed an interesting anti-AChE and/or anti-BChE activity (IC50 =0.56-1.58 mg/mL), which can be explained, at least partially, by the presence of some of their constituents. Among the metabolites tested, the best activity was revealed for the flavonoids apigenin, luteolin and diosmetin, and the sesquiterpene lactone 8-epiixerisamine A (IC50 =68.09-299.37 μM).

Anti-Aging Activity and Modes of Action of Compounds from Natural Food Sources

Aging is a natural and inescapable phenomenon characterized by a progressive deterioration of physiological functions, leading to increased vulnerability to chronic diseases and death. With economic and medical development, the elderly population is gradually increasing, which poses a great burden to society, the economy and the medical field. Thus, healthy aging has now become a common aspiration among people over the world. Accumulating evidence indicates that substances that can mediate the deteriorated physiological processes are highly likely to have the potential to prolong lifespan and improve aging-associated diseases. Foods from natural sources are full of bioactive compounds, such as polysaccharides, polyphenols, carotenoids, sterols, terpenoids and vitamins. These bioactive compounds and their derivatives have been shown to be able to delay aging and/or improve aging-associated diseases, thereby prolonging lifespan, via regulation of various physiological processes. Here, we summarize the current understanding of the anti-aging activities of the compounds, polysaccharides, polyphenols, carotenoids, sterols, terpenoids and vitamins from natural food sources, and their modes of action in delaying aging and improving aging-associated diseases. This will certainly provide a reference for further research on the anti-aging effects of bioactive compounds from natural food sources.