Bicyclic Monoterpene Research Articles

Ashbya gossypii as a versatile platform to produce sabinene from agro-industrial wastes

BackgroundAshbya gossypii is a filamentous fungus widely utilized for industrial riboflavin production and has a great potential as a microbial chassis for synthesizing other valuable metabolites such as folates, biolipids, and limonene. Engineered strains of A. gossypii can effectively use various waste streams, including xylose-rich feedstocks. Notably, A. gossypii has been identified as a proficient biocatalyst for producing limonene from xylose-rich sources. This study aims to investigate the capability of engineered A. gossypii strains to produce various plant monoterpenes using agro-industrial waste as carbon sources.ResultsWe overexpressed heterologous terpene synthases to produce acyclic, monocyclic, and bicyclic monoterpenes in two genetic backgrounds of A. gossypii. These backgrounds included an NPP synthase orthogonal pathway and a mutant erg20F95W allele with reduced FPP synthase activity. Our findings demonstrate that A. gossypii can synthesize linalool, limonene, pinene, and sabinene, with terpene synthases showing differential substrate selectivity for NPP or GPP precursors. Additionally, co-overexpression of endogenous HMG1 and ERG12 with heterologous NPP synthase and terpene synthases significantly increased sabinene yields from xylose-containing media. Using mixed formulations of corn-cob lignocellulosic hydrolysates and either sugarcane or beet molasses, we achieved limonene and sabinene productions of 383 mg/L and 684.5 mg/L, respectively, the latter representing a significant improvement compared to other organisms in flask culture mode.ConclusionsEngineered A. gossypii strains serve as a suitable platform for assessing plant terpene synthase functionality and substrate selectivity in vivo, which are crucial to understand monoterpene bioproduction. The NPP synthase pathway markedly enhances limonene and sabinene production in A. gossypii, achieving levels comparable to those of other industrial microbial producers. Furthermore, these engineered strains offer a novel approach for producing monoterpenes through the valorization of agro-industrial wastes.

Topical Therapies for Periorbital Dyschromia: A 30-Year Review of the Literature.

Periorbital dyschromia (POD) is a prevalent dermatologic problem with multifactorial etiology, making treatment outcomes inconsistent and unclear. To evaluate and compose a comprehensive review of topical ingredients proven to be effective in the treatment of POD. Scopus, PubMed, and OVID databases were searched in a span of 30 years through December 31, 2023, to identify articles with original findings of topical therapies for the treatment of POD. Findings of interest were objectively and subjectively measured regarding pigmentation, skin texture, aesthetic improvement, elasticity, hydration, and eye-bag volume. The database searches yielded 339 unique studies. After screening and review, 22 studies were included totaling 13 nonrandomized control trials, 7 randomized clinical trials, 1 retrospective case series, and 1 prospective single-arm study. Studies included all reported statistically significant results with topical therapies inclusive of acids, bark extract, bicyclic monoterpene diols, caffeine, combo ingredient serums, ethyl ximenynate, gentiopicroside, glycosaminoglycans, growth factors, topical PRP, and vitamins. The findings of this review suggest that topical therapies can be effective in the treatment of POD. Future trials should focus on delineating specific etiology of POD and evaluation of therapies specific to their cause.

Metabolic engineering of the borneol and camphor degradation pathways in Pseudomonas to produce optically pure bicyclic monoterpenes

Borneol, a medicinally important bicyclic monoterpene, facilitates drug transport across mucous membranes and the blood-brain barrier. Derivatives of borneol and camphor also have numerous biomedical applications. Borneol is currently industrially synthesized via the conversion of turpentine and α-pinene. However, the major product is racemic isoborneol rather than racemic borneol. Both borneol and isoborneol are degraded by the soil bacterium Pseudomonas via a well-established degradation pathway. Two indigenous Pseudomonas strains were used to convert racemic isoborneol to other optically pure bicyclic monoterpenes here. Our results showed that deletion of the camE2,5 gene alone from the strain TCU-HL1 genome led to the complete loss of borneol and camphor degradation ability. Knockout of both camE2,5 and bdh1 (TCU-HL1Δbdh1ΔcamE2,5) restored the degradation capability as the role of Bdh1 was replaced by that of Bdh2. This mutant converted racemic isoborneol into an optically pure bicyclic monoterpene, 2,5-diketocamphane, with a 45% recovery yield. RT-qPCR results suggested that camE2,5 expression plays a pivotal role in regulating the borneol/camphor degradation cluster. While (+)-borneol, (–)-borneol and (+)-camphor can be obtained from plants for mass production purposes, (–)-camphor cannot be obtained in the same manner. P. monteilii TCU-CK1 converted racemic isoborneol into (–)-camphor and 3,6-diketocamphane, with 15% and 10% recovery yields, respectively. In conclusion, we report the role of camE2,5 in regulating the borneol/camphor degradation operon and biotransformation methods to produce several optically pure bicyclic monoterpenes.

Accurate structures and rotational constants of bicyclic monoterpenes at DFT cost by means of the bond-corrected Pisa composite scheme (BPCS).

The structural, conformational, and spectroscopic properties in the gas phase of 20 bicyclic monoterpenes and monoterpenoids have been analyzed by a new accurate, reduced-cost computational strategy. In detail, the revDSD-PBEP86 double-hybrid functional in conjunction with the D3BJ empirical dispersion corrections and a suitable triple-zeta basis set provides accurate geometrical parameters, whence equilibrium rotational constants, which are further improved by proper account of core-valence correlation. Average deviations within 0.1% between computed and experimental rotational constants are reached when taking into account the vibrational corrections obtained by the B3LYP functional in conjunction with a double-zeta basis set in the framework of second-order vibrational perturbation theory. In addition to their intrinsic interest, the studied terpenes further extend the panel of systems for which the proposed strategy has provided accurate results at density functional theory cost. Therefore, a very accurate yet robust and user-friendly tool is now available for systematic investigations of the role of stereo-electronic effects on the properties of large systems of current technological and/or biological interest by experimentally oriented researchers.

Is Camphor the Future in Supporting Therapy for Skin Infections?

The aim of this review is to present the potential application of camphor-a bicyclic monoterpene ketone-in the prevention of skin infections. Skin diseases represent a heterogeneous group of disorders characterized by prolonged symptoms that significantly diminish the quality of life. They affect the dermis, the epidermis, and even subcutaneous tissue. They very often have a bacterial or fungal background. Therapy for dermatological skin disorders is difficult and long-term. Therefore, it is important to find a compound, preferably of natural origin, that (i) prevents the initiation of this infection and (ii) supports the skin's repair process. Based on its documented anti-inflammatory, antibacterial, antifungal, anti-acne, anesthetic, strengthening, and warming properties, camphor can be used as a preventative measure in dermatological infectious diseases and as a component in medical and cosmetic products. This work discusses the structure and physicochemical properties of camphor, its occurrence, and methods of obtaining it from natural sources as well as through chemical synthesis. The use of camphor in industrial preparations is also presented. Additionally, after a detailed review of the literature, the metabolism of camphor, its interactions with other medicinal substances, and its antimicrobial properties against bacteria and fungi involved in skin diseases are discussed with regard to their resistance.

(+)-Borneol Protects Dopaminergic Neuronal Loss in Methyl-4-phenyl-1,2,3,6-tetrahydropyridine-Induced Parkinson's Disease Mice: A Study of Dopamine Level using In Vivo Brain Microdialysis.

Considerable research efforts have been directed toward the symptom relief of Parkinson's disease (PD) by attenuating dopamine (DA) depletion. One common feature of these existing therapies is their unavailability of preventing the neurodegenerative process of dopaminergic neurons. (+)-Borneol, a natural highly lipid-soluble bicyclic monoterpene, has been reported to regulate the levels of monoamine neurotransmitters in the central nervous system and exhibit neuroprotective effects. However, the effect of (+)-borneol on the dopaminergic neuronal loss of methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice is not defined. Herein, we first report that 30 mg/kg (+)-borneol significantly attenuated the motor deficits of PD mice, which benefits from markedly increasing the level of DA and decreasing the metabolic rate of DA in the striatum of conscious and freely moving mouse detected by ultraperformance liquid chromatography tandem mass spectrometry online combined with in vivo brain microdialysis sampling. It is worth noting that the enhanced level of DA by (+)-borneol was enabled by the reduction in loss of tyrosine hydroxylase-immunoreactive dopaminergic neurons in the substantia nigra and striatum and promotion of reserpine- or nomifensine-induced DA release in PD mice. Interestingly, (+)-borneol evidently inhibited the decreased expression levels of DA transporter (DAT) and vesicular monoamine transporter 2 (VMAT2) on the MPTP mouse model of PD. Moreover, (+)-borneol suppressed the neuroinflammation by inhibiting the production of IL-1β, IL-6, and TNF-α and attenuated oxidative stress by decreasing the level of MDA and increasing the activities of SOD and GSH-px in PD mice. These findings demonstrate that (+)-borneol protects DA neurons by inhibiting neuroinflammation and oxidative stress. Further research work for the neuroprotection mechanism of (+)-borneol will focus on reactive oxygen species-mediated apoptosis. Therefore, (+)-borneol is a potential therapeutic candidate for retarding the neurodegenerative process of PD.

The behavioral sensitivity of mice to acyclic, monocyclic, and bicyclic monoterpenes.

Monoterpenes are a large class of naturally occurring fragrant molecules. These chemicals are commonly used in olfactory studies to survey neural activity and probe the behavioral limits of odor discrimination. Monoterpenes (typically in the form of essential oils) have been used for centuries for therapeutic purposes and have pivotal roles in various biological and medical applications. Despite their importance for multiple lines of research using rodent models and the role of the olfactory system in detecting these volatile chemicals, the murine sensitivity to monoterpenes remains mostly unexplored. We assayed the ability of C57BL/6J mice to detect nine different monoterpenes (the acyclic monoterpenes: geraniol, citral, and linalool; the monocyclic monoterpenes: r-limonene, s-limonene, and γ-terpinene; and the bicyclic monoterpenes: eucalyptol, α-pinene, and β-pinene) using a head-fixed Go / No-Go operant conditioning assay. We found that mice can reliably detect monoterpene concentrations in the low parts per billion (ppb) range. Specifically, mice were most sensitive to geraniol (threshold: 0.7 ppb) and least sensitive to γ-terpinene (threshold: 18.1 ppb). These estimations of sensitivity serve to set the lower limit of relevant monoterpene concentrations for functional experiments in mice. To define an upper limit, we estimated the maximum concentrations that a mouse may experience in nature by collating published headspace analyses of monoterpene concentrations emitted from natural sources. We found that natural monoterpenes concentrations typically ranged from ~1 to 1000 ppb. It is our hope that this dataset will help researchers use appropriate monoterpene concentrations for functional studies and provide context for the vapor-phase delivery of these chemicals in studies investigating their biological activity in mice.

Synthesis and Properties of New Conjugates of Isatin and Bicyclic Monoterpenes

Synthesis and Properties of New Conjugates of Isatin and Bicyclic Monoterpenes

Chimgin from Ferula haussknechtii as AChE inhibitor and confirmation of the absolute configuration

Alzheimer’s disease (AD) is the most common cause of dementia worldwide and is classified as a neurodegenerative disorder. From a drug design perspective, natural products (NPs) are more drug-like and are highly compatible with biological systems compared to most synthetic libraries. NPs provide a more efficient and cost-effective approach to new drug discovery. However, the complexity of NPs makes their identification a challenging task. Chimgin, a bicyclic monoterpene with three chiral centers, exhibits a wide range of biological activity. Despite this, the exact structure of chimgin has remained unclear until now. In this study, we quantified the amount of chimgin in Ferula haussknechtii using analytical Reversed-phase high-pressure liquid chromatography equipped with photodiode array detector (RP-HPLC-PDA). Furthermore, we determined the absolute configuration of chimgin through electronic circular dichroism (ECD) spectroscopy and time-dependent density functional theory (TDDFT) calculations. Finally, we evaluated its inhibitory effect on AChE through in vitro and in silico studies. The extraction process yielded an output of 2.82 ± 0.10% with an exact amount of 0.62 ± 0.04 mg of chimgin per 100 g of plant. Based on the results of ECD and TDDFT calculation, the absolute configuration of chimgin was determined to be 1S, 2S, 4S. Chimgin exhibited an inhibitory effect on AChE with an IC50 of 37.43 µM and its mechanism of action was found to be competitive. Highlights Chimgin was isolated from the roots of Ferula haussknechtii. The amount of chimgin in the plant was determined by RP-HPLC-PDA. Its absolute configuration of chimgin was determined using ECD. In vitro acetylcholinesterase activity of the chimgin was evaluated. The docking and molecular dynamic simulation of chimgin was done. Communicated by Ramaswamy H. Sarma

Monoterpene Thiols: Synthesis and Modifications for Obtaining Biologically Active Substances.

Monoterpene thiols are one of the classes of natural flavors that impart the smell of citrus fruits, grape must and wine, black currants, and guava and are used as flavoring agents in the food and perfume industries. Synthetic monoterpene thiols have found an application in asymmetric synthesis as chiral auxiliaries, derivatizing agents, and ligands for metal complex catalysis and organocatalysts. Since monoterpenes and monoterpenoids are a renewable source, there are emerging trends to use monoterpene thiols as monomers for producing new types of green polymers. Monoterpene thioderivatives are also known to possess antioxidant, anticoagulant, antifungal, and antibacterial activity. The current review covers methods for the synthesis of acyclic, mono-, and bicyclic monoterpene thiols, as well as some investigations related to their usage for the preparation of the compounds with antimicrobial properties.

Chemical Composition and Future Perspectives of Essential Oil Obtained from a Wild Population of Stachys germanica L. Distributed in the Balkan Mountains in Bulgaria

Stachys germanica L. (Lamiaceae) is a plant associated with a rich history in the traditional medicine of Iran, Turkey, and Serbia. However, researchers have not fully investigated the pharmacological potential of the herb, and scientific data on this plant species are limited. The aim of the current study was to evaluate the chemical composition of the essential oil (EO) obtained from the aerial parts of S. germanica L. growing wild in Bulgaria and to perform a comparative analysis of the chemical composition of EOs obtained from the same plant species from other geographical regions. For the evaluation of the chemical profile of the isolated EO, gas chromatographic analysis with mass spectrometry was performed. The most abundant terpene class was oxygenated monoterpenes, which accounted for 59.30% of the total EO composition. The bicyclic monoterpene camphor, as a compound of this class, was identified as the major constituent in the EO, accounting for 52.96% of the total oil composition. The chemical profile of Bulgarian EO is quite different compared to that of EOs from other regions. It is the only one to contain more than 50% camphor. In addition, EO contains significant amounts of the diterpene geranyl p-cymene (10.49%). This is the first study describing the chemical composition of EO from Bulgarian Stachys germanica L., and our results reveal some future perspectives for the evaluation of the biological activity of EO from the studied plant species as a new therapeutic agent or natural remedy targeting different medical conditions. The EO has a promising potential to be used as a biopesticide and repellent as well, an environmentally friendly and safer alternative to standard pesticides.

Sabinene: A New Green Solvent Used in the Synthesis of Thiazolo[5,4-b]pyridines by Thermal or Microwave Activation.

Following the work already carried out in our laboratory on eucalyptol, a new green solvent derived from biomass, we are now looking at sabinene as another new green solvent. Sabinene is also derived from biomass, has no known toxicity and can be recycled by distillation. We have shown that it can be used as it is or distilled to synthesize thiazolo[5,4-b]pyridine heterocycles by thermal activation or microwave irradiation. This new solvent was compared with various conventional and green solvents. The conditions were optimised to enable us to carry out the syntheses in satisfactory yields, and we were able to show that sabinene, a natural bicyclic monoterpene, could be used effectively as a solvent.

Comparative Analysis of Chemical Profile and Biological Activity of Juniperus communis L. Berry Extracts.

Researchers are looking for the most effective ways to extract the bioactive substances of Juniperus communis L. berries, which are capable of displaying the greatest range of biological activity, namely antimicrobial potential "against phytopathogens", antioxidant activity and nematocidal activity. This study provides detailed information on the chemical activity, group composition and biological activity of the extracts of juniper berries of 1- and 2-year maturity (JB1 and JB2), which were obtained by using different solvents (pentane, chloroform, acetone, methanol and 70% ethanol) under various extraction conditions (maceration and ultrasound-assisted maceration (US)). Seventy percent ethanol and acetone extracts of juniper berries were analyzed via gas chromatography-mass spectrometry, and they contained monoterpenes, sesquiterpenes, polysaccharides, steroids, fatty acid esters and bicyclic monoterpenes. The antimicrobial activity was higher in the berries of 1-year maturity, while the acetone extract obtained via ultrasound-assisted maceration was the most bioactive in relation to the phytopathogens. Depending on the extraction method and the choice of solvent, the antioxidant activity with the use of US decreased by 1.5-1.9 times compared to the extracts obtained via maceration. An analysis of the nematocidal activity showed that the sensitivity to the action of extracts in Caenorhabditis elegans was significantly higher than in Caenorhabditis briggsae, particularly for the acetone extract obtained from the juniper berries of 1-year maturity.

Dynamic migration mechanism of borneol synergistic polyethylene glycol for the construction of silicon-acrylate antifouling coating

Silicone-based coatings are vulnerable to marine fouling organisms in static environments, which seriously hampers its practical application. Here, an amphiphilic acrylate polymer is designed by hydrophilic polyethylene glycol and antibacterial borneol, which is introduced into polydimethylsiloxane (PDMS) by covalent linking to prepare antifouling coatings. XPS and CA tests prove that amphiphilic acrylate polymer can migrate to coating surface in the marine environment to maximize antifouling properties. Mytilus edulis foot protein adhesion test find it can weaken interface force between Mefp-3 and surface. Laboratory antifouling performance evaluations confirm that the coatings are effective against the adhesion of bacteria (86.72 % reduction for E. coli), diatoms (87.76 % reduction for Nitzschia closterium). The good antifouling properties of coatings are ascribed to the synergistic effect among unique bicyclic monoterpene structure of natural non-toxic borneol and amphiphilic acrylate polymer on surface of coatings. Moreover, the coating is less harmful to the marine ecological balance than traditional coatings containing toxic biocides due to the introduction of natural non-toxic borneol. This work contributes new insights in the exploration of environmentally friendly coating with excellent static antifouling performance.

Biochemical and histological study of spermatogenic activity in male albino rats treated with Cantharis Q

Cantharidin is a bioactive toxin produced by the blister beetles commonly called Spanish fly. This natural compound is a bicyclic monoterpene (C10H12O4 ) that has clinical application as an anti-inflammatory, antiviral as well as antitumor agent and has been widely used to treat a variety of skin-related diseases. There are several reports of consumption of dried blister beetles and their traditional formulations due to a long history of the supposed aphrodisiac property of cantharidin. The present study, therefore, aimed at investigating the biochemical and histological changes in the testes of male albino rats of Wistar strain due to oral intake of Cantharis Q, a crude alcoholic extract of blister beetle Lytta vesicatoria used as mother tincture and as diluted potentized form in homeopathy. The experimental rats were given Cantharis Q dosage of 500 µg/Kg body weight for 60 days and the subsequent autorecovery was also studied after 30 days without treatment. The treated rats showed a significant decrease in the weight of testis, seminiferous tubular diameter and sperm count. Activity of testicular acid phosphatase (ACP), alkaline phosphatase (ALP), hyaluronidase (HL) enzyme and content of cholesterol, total protein, DNA and RNA decreased significantly whereas activity of beta-glucuronidase (BG) enzyme and glycogen was significantly increased. Spermatogenesis stages VIII, IX and X showed sloughing of round spermatids into the tubular lumen. The animals kept for autorecovery showed only partial improvement. Thus, it could be concluded that the treatment had a negative impact on the physiological function of testis of albino rat causing detrimental effects on the spermatogenic activity

Attenuation of CFA-induced chronic inflammation by a bicyclic monoterpene fenchone targeting inducible nitric oxide, prostaglandins, C-reactive protein and urea.

Fenchone (a bicyclic monoterpene) is present in the essential oils of plant species like Foeniculum vulgare and Peumus boldus and is used to treat GIT disorders. Research reports have indicated its strong anti-inflammatory, antioxidant, and anti-nociceptive properties. The present study was designed to investigate fenchone's anti-arthritic effects in a rat model of chronic joint inflammation (Complete Freud's Adjuvant-mediated inflammation [CFA]). Molecular docking analysis revealed a high binding interaction of fenchone with inducible nitric oxide synthase (iNOS), Interleukin-17, Prostaglandin E Receptor EP4, and Cycloxygenase-2 (COX-2), indicating its anti-inflammatory efficacy using computational tests. Fenchone treatment at 100mg/kg, 200mg/kg, and 400mg/kg significantly enhanced the tail-flick latency when compared with the solvent-treated group. Correspondingly, the raised mRNA values of iNOS, IL-17, IL-1β, IL-6, TNF-α, and COX-2 in solvent-treated group were significantly reduced following treatment with fenchone. Moreover, fenchone significantly lowered spleen and thymus indices, Nitric oxide (NO) and PGE2 values as compared to solvent-treated group. Hence, the results of the present study indicated that fenchone has a potent anti-inflammatory effect by inhibiting pro-inflammatory markers and thus may have therapeutic potential for chronic joint inflammation as well as chronic inflammatory disorders.

Active components and potential mechanism of Taohong Siwu Decoction in regulating ischemic stroke based on target cell trapping combined with network pharmacology, molecular docking, and experimental validation

The potential anti-stroke active components in Taohong Siwu Decoction(THSWD) were identified by target cell trapping coupled with ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry(UPLC-Q-TOF-MS). The underlying mechanism of active components in THSWD in the treatment of ischemic stroke(IS) was explored by network pharmacology, molecular docking, and experimental validation. The UPLC-Q-TOF-MS technology combined with the UNIFI data analysis platform was used to analyze the composition of the cellular fragmentation fluid after co-incubation of THSWD with target cells. The targets of potential active components and IS were collected by network pharmacology, and the common targets underwent protein-protein interaction(PPI), Gene Ontology(GO), and Kyoto Encyclopedia of Genes and Genomes(KEGG) signaling pathway enrichment analyses. The target cell trapping component-core target-signaling pathway network was constructed, and the active components were molecularly docked to the top targets in the PPI network, followed by pharmacodynamic validation in vitro. Fifteen active components were identified in the target cellular fragmentation fluid, including bicyclic monoterpenes, cyanoglycosides, flavonols, quinoid chalcones, phenylpropanoids, and tannins. As revealed by the analysis of network pharmacology, THSWD presumably regulated PI3K-AKT, FoxO, MAPK, Jak-STAT, VEGF, HIF-1, and other signaling pathways to affect inflammatory cascade reaction, angiogenesis, oxidative stress, pyroptosis, apoptosis, and other pathological processes via paeoniflorin, butylphthalide, dehydrated safflower yellow B, 3,4-dicaffeoylquinic acid, amygdalin, paeoniflorin, and ligusticolactone. Molecular docking and in vitro pharmacodynamic validation revealed that the target cell trapping active components could promote neovascularization in rat brain microvascular endothelial cells(rBMECs) in the oxygen-glucose deprivation/reoxygenation(OGD/R) model. The application of target cell trapping coupled with UPLC-Q-TOF-MS technology can rapidly screen out the potential active components in THSWD. The active components of THSWD can be predicted to intervene in the pathogenesis of IS through network pharmacology, and molecular docking combined with experimental validation can further clarify the efficacy, thus providing a theoretical basis for research ideas on the pharmacodynamic substance basis of traditional Chinese medicine compounds.

A Study of the Chemical Composition, Antioxidant Potential, and Acute Toxicity of Bulgarian Tanacetum vulgare L. Essential Oil.

Common tansy (Tanacetum vulgare L.) is a plant with medicinal properties that has traditionally been used in folk medicine for its anthelmintic, antispasmodic, and choleretic effects, for the treatment of diarrhea and digestive problems, and externally, as an insecticide in veterinary practices. In the current study, we investigated, for the first time, the chemical profile and antioxidant activity of essential oil from a wild population of T. vulgare L. growing in Bulgaria. Common tansy essential oil (EO), which is rich in bicyclic monoterpenes, was obtained using hydrodistillation and characterized by using gas chromatography-mass spectrometry (GC-MS). Thirty-seven compounds were identified in Bulgarian tansy EO. Among the major constituents were oxygenated monoterpenes, including compounds such as camphor (25.24%), trans-chrysantenyl acetate (18.35%), cis-verbenol (10.58%), thujone (6.06%), eucaliptol (5.99%), and α-campholenal (5.98%). The analysis results identified the essential oil from T. vulgare L. grown in the western Rhodope Mountains of Bulgaria as the camphor chemotype. Furthermore, its antioxidant activity was analyzed using the oxygen radical absorbance capacity (ORAC) method and was found to be 605.4 ± 49.3 µmol TE/mL. The essential oil was also tested for single-dose acute toxicity on Wistar rats and was found to be non-toxic by oral administration. The mean lethal dose by intraperitoneal administration was LD50 i.p. = 14.9 g/kg body weight. The results of the conducted study can serve as a basis for the evaluation and subsequent exploration of other pharmacotherapeutic effects of the essential oil obtained from the inflorescences of the Bulgarian species T. vulgare L.

Fabrication of an anti-fouling coating based on epoxy resin with a double antibacterial effect via an in situ polymerization strategy

The hull and subsea equipment are often plagued by widespread marine biofouling, so developing a sustainable environmental protection antifouling paint is urgent. The study designed and developed an antifouling composite coating system (E44-Ag-PGI) with a synergistic antibacterial effect based on the dual strategy of the bacteriostatic effect of stereochemical structure on polymer surface and release sterilization of metal nanoparticles. Firstly, an antifouling agent (PGI) was prepared by simple radical polymerization by combining glycidyl methacrylate with borneol, a complex bicyclic monoterpene structure extracted from plants. Then bisphenol A epoxy resin with strong adhesion to metal was selected as the base material. The synthetic antifouling agent with epoxy groups was polymerized in situ into the epoxy resin network, and compared with pure epoxy resin, the elongation at break of E44-Ag-PGI coating with 20 % PGI content increased from 40.37 % to 124.8 %, which was mainly attributed to the introduction of a soft chain of antifouling agent polymer, which improved the flexibility of the coating. Meanwhile, the antibacterial efficiency of the coating against Pseudomonas aeruginosa and Staphylococcus aureus was 97.69 % and 95.9 %, respectively. This excellent antibacterial performance was mainly attributed to the synergistic antibacterial action of natural borneol and AgNPs. In addition, the biofilm and diatom resistance experiments of the coating showed that the coating also has an excellent antifouling effect. This provided a new research idea for environmentally friendly antifouling coatings.

Phytochemistry and Pharmacology of Indian Traditional Plant Hyssop (Hyssopus officinalis L.): A Review

Abstract: Hyssopus officinalis is a traditional medicinal plant that belongs to the family Lamiaceae, which has been used from centuries for various purposes like carminative, expectorant, cough reliever. It has been used for the treatment of numerous diseases in patients such as ulcers, asthma, jaundice, leprosy, dropsy, bronchitis, COPD, diabetes, AIDS, bacterial and fungal infections as an herbal remedy due to its fewer side effects and is more efficacies than other traditional medicine. Major classes of chemical compounds found in H. officinalis essential oil are bicyclic monoterpenes, monoterpenoids, acyclic monoterpenes, phenolic monoterpenoids, monocyclic monoterpenes, monocyclic sesquiterpenes, tricyclic sesquiterpenes, bicyclic sesquiterpenes, tricyclic sesquiterpenoids, straight chain saturated hydrocarbons. Some of the major chemical constituents present in the H. officinalis are β-pinene, α-pinene, 1, 8-cineole, apigenin, diosmin, caffeic acid, rosmarinic acid, cis-pinocamphone, trans-pinocamphone, iso-pinocamphone, pinocarvone, which are responsible for its various pharmacological activity. Various studies have been performed on the pharmacological activity of its extract, such as antioxidant, antimicrobial, anti-diabetic, anticancer, antiviral, anti-inflammatory, analgesic, anti-leishmanial, anthelmintic, anti-protozoal and anti-anxiety. Recently, it is use as an anticancer agent has been demonstrated by studying its cytotoxic and apoptotic effects on breast cancer and colon cancer cells. It is used as a potent antibacterial and antifungal agent was studied on the antibiotic-resistant bacterial and fungal strains recently, which can be further useful in developing herbal medicine against AMR. It is an excellent natural antioxidant due to the presence of polyphenolic compounds, and H. officinalis is used in various food industries as a source of natural antioxidants, which has minimum side effects as compared to artificial antioxidants. Furthermore, the pharmacological activity of these individual chemical constituents in H. officinalis extract still needs to be investigated for identifying the effectiveness of this plant in the natural treatment of various diseases. This review aims to collect various data regarding the traditional herbal plant hyssop (Hyssopus Officinalis), including its photochemistry, chemical structures of the phyto-constituents and pharmacological profile, along with all the pharmacological models. This plant has significant importance in the health industry, so further studies are required on its effective usage against various emerging health problems, including COVID-19, cancer, diabetes, AMR.