Undescribed sesquiterpenoids with NO production inhibitory activity from oleo-gum resin of Commiphora myrrha.

Six undescribed cadinane sesquiterpenoids (1-6), two undescribed guaiane sesquiterpenoids (7-8), and an undescribed germacrane sesquiterpenoid (9) were isolated from the oleo-gum resin of Commiphora myrrha. Their structures were determined by the analysis of 1D/2D NMR and HRESIMS data, as well as quantum chemical ECD and NMR calculations. All the sesquiterpenoids were evaluated for their NO production inhibitory activity in LPS-stimulated RAW 264.7 mouse monocyte-macrophages. The results revealed that commiphone A (1) and commipholide D (7) exhibited significant inhibitory effect on NO generation with IC50 values of 18.6 ± 2.0 and 37.5 ± 1.5 µM, respectively. Furthermore, 1 and 7 dose-dependently inhibited the mRNA expression of inflammatory cytokines IL-1ß, IL-6 and TNF-α induced by LPS in the RAW264.7 cells, indicating that 1 and 7 possess potent anti-inflammatory activity in vitro.

White spot enamel lesions - is treatment or prevention the answer to this 'no win scenario'?

DESIGN: Prospective, randomized, double-blind, multicenter clinical trial. CASE SELECTION: Participants between 12 and 25 years old, who were generally healthy, with 2 or more white spot lesions on the labial surface of anterior dentition. DATA ANALYSIS: 79 patients who developed white spot lesions (WSL) on the labial surface of anterior teeth following orthodontic treatment were randomly assigned to 4 intervention groups. Group 1 received 5% sodium fluoride varnish every 6 months, the second group received CPP-ACP every 6 months, the third group was treated with resin infiltration at the initial visit followed by placebo every 6 months, and the final group which was the control group was coated with 1400 ppm fluoride toothpaste every 6 months. All the candidates were instructed to brush twice daily using a specific toothbrush and 1400 ppm fluoride toothpaste. The study lasted for 12 months, and photographs of the teeth with WSL were taken before and after completion of the intervention. Photographs were analyzed using ImageJ software to compare the changes in the percentage of WSL area to total tooth surface area among the four study groups. The distribution differences among groups were compared using nonparametric tests and differences between baseline and 1-year follow-up parameters were analyzed using paired chi-square tests. RESULTS: Reduction in the area of WSL were noted in all groups, with different levels of significance. The percentage reduction was 46.62% in the resin infiltration group and it was significantly higher than the remaining interventions. Fluoride varnish group had 26.57% reduction, the CPP-ACP group had 28.64% reduction and the control group had 29.75% reduction in the WSL area. Plaque index was noted to have significant correlation with the change in WSL area with higher plaque index scores demonstrating lesser reduction in WSL. CONCLUSIONS: The study found that resin infiltration significantly reduced the WSL area after 1-year follow-up. Fluoride toothpaste with or without CPP-ACP and fluoride varnish produced some therapeutic effects.

Design of Cell-Adhesive Shellac Derivatives and Endowment of Photoswitchable Cell-Adhesion Properties.

The emergence of new biodegradable cell-adhesion materials is an attractive topic in biomaterial chemistry, particularly for the development of cell incubation scaffolds and drug encapsulation materials used in in situ regenerative therapy. Shellac is a natural resin with unique film-forming properties and high miscibility with various chemicals, in addition to being biodegradable and nontoxic to biological systems. However, since native shellac does not adhere to mammalian cells, there have been no reports of using shellac to develop cell-adhesive biomaterials. In this study, we report on the development of cell-adhesive shellac derivatives through slight chemical modification. Shellac is a mixture of oligoesters that consists of hydroxyl fatty acids and resin acids, and therefore, all oligomers have one carboxylic acid group at the terminal. We discovered that a simple modification of hydrophobic chemical groups, particularly those containing aromatic groups in the ester form, could dramatically improve cell-adhesion properties for mammalian cells. Furthermore, by using photocleavable esters containing aromatic groups, we successfully endowed photoswitchable properties in cell adhesion. Given that shellac is a low-cost, biodegradable, and nontoxic natural resin, the modified shellacs have the potential to become new and attractive biomaterials applicable to in situ regenerative therapy.

Chios Mastic Gum: Chemical Profile and Pharmacological Properties in Inflammatory Bowel Disease: From the Past to the Future.

Chios mastic gum, the product of the tree Pistacia lentiscus var. Chia, has been used for more than 2500 years in traditional Greek medicine for treating several diseases, thanks to the anti-inflammatory and antioxidant properties of its components. Despite the long-time use of mastic in gastroenterology and in particular in chronic-inflammation-associated diseases, to date, the literature lacks reviews regarding this topic. The aim of the present work is to summarize available data on the effects of P. lentiscus on inflammatory bowel disease. A comprehensive review of this topic could drive researchers to conduct future studies aimed at deeply investigating P. lentiscus effects and hypothesizing a mechanism of action. The present review, indeed, schematizes the possible bioactive components of mastic gum. Particular care is given to P. lentiscus var. Chia medicaments' and supplements' chemical compositions and their pharmacological action in inflammatory bowel disease.

Mastic (Pistacia lentiscus) gum and oral health: a state-of-the-art review of the literature.

The aim of this state-of-the-art review is to provide a comprehensive overview of the various therapeutic effects of Mastic (Pistacia lentiscus) gum on oral health. The search of the literature was conducted across thirteen databases for relevant publications published through May 2022 in English, Arabic, or Greek using a combination of keywords and phrases. Out of 246 papers, the search procedure identified 14 papers for inclusion. Mastic gum displayed antibacterial and antimicrobial properties and inhibited plaque accumulation, constituting a beneficial adjuvant in caries prevention. In the treatment and prevention of periodontal diseases, Pistacia lentiscus essential oil provided effective antibacterial activity against a variety of periodontal bacteria as well as anti-inflammatory properties. For oral cancer, several clinical trials revealed interesting results against cell proliferation, induction of apoptosis, and regulation of intracellular signaling pathways. This indicates the potential of Mastic gum to serve as a preventive and therapeutic agent for oral mucosa inflammation and oral cancer. No notable toxic or side effects were reported in the clinical trials reviewed. This review highlights the various beneficial effects of Mastic gum in the prevention and potential treatment of oral diseases. Further research targeting Pistacia lentiscus products is required in order to validate and utilize these products to prevent and to treat oral health diseases.

Effects of copal resin extraction on the diversity and composition of species in tropical deciduous forests.

Composition and floristic diversity of ecosystems subject to overexploitation, such as tropical deciduous forests where copal resin (Bursera bipinnata, Bursera copallifera) is extracted, are of great importance for understanding the ecological functioning of these ecosystems. This study analyzed the species composition and diversity in a natural population subject to copal extraction in San Juan Raboso Izúcar de Matamoros, Puebla, Mexico. A total of 54 sampling units were established, and the number of individuals and crown diameter for each tree species were recorded. For shrubs, succulents, acaulescent rosetophytes and climbers, the number of individuals and the area of cover were quantified. Based on the parameters of abundance, frequency, and relative dominance, the importance value index (IVI) was calculated. Diversity was evaluated using the Shannon index [Formula: see text]. In total, 29 species were identified, distributed across 11 botanical families and 21 genera. The Fabaceae family was the richest, followed by the Burseraceae family, which includes the species that extract copal, but Opuntia streptacantha was the species with the most ecological weight. In this study, the Shannon index [Formula: see text] averaged 1.45, which indicates that the community was mildly diverse.

Efficient Neural Differentiation of Mouse Embryonic Stem Cells by Mastic Gum.

Purpose: Promoting neurogenesis is a promising strategy to treat neurodegenerative disorders. In the present study, we aimed to evaluate the effect of mastic gum resin from the Pistacia lentiscus var. Chia (Anacardiaceae family) in proliferation capacity and differentiation of embryonic mesenchymal stem cells into a neural lineage. Methods: For this purpose, mastic gum was applied as a neural inducer for stem cell differentiation into the neuronal lineage. Following treatment of embryonic stem cells (ESCs) with mastic gum, verification differentiation of the ESCs into the neuronal lineage, gene expression analysis, and immunocytochemistry staining approach were performed. Results: Gene expression analysis demonstrated that mastic gum increased the expression level of neuron markers in the ESCs-derived neuron-like cells. Moreover, our immunocytochemistry staining results of two important neural stem cell markers, including Nestin and microtubule-associated protein-2 (Map2) expression confirmed that mastic gum has the potential to promote neuronal differentiation in ESCs. Conclusion: In summary, the use of mastic gum to stimulate the differentiation of ESCs into a neural lineage can be considered as a good candidate in stem cell therapy.

Boswellic acids as promising agents for the management of brain diseases.

Boswellic acid (BA)s are pentacyclic triterpenic acids present in gum resin of Boswellia species (such as B. serrata and B. carterii). They possess a variety of pharmacological effects such as anti-inflammatory, anti-oxidant, and anti-excitotoxic effects. These properties may have potential therapeutic implication in neurological disorders. Notably, the BAs-induced neuroprotection is proposed to be associated with the ability to reduce neurotoxic aggregates, decrease oxidative stress, and improve cognitive dysfunction. Recently, BAs have been suggested as potential agents for the treatment of brain tumors due to their potential to attenuate cell proliferation, migration, metastasis, angiogenesis, and promote apoptosis during both in vitro and in vivo studies. The present review aims to address these studies and highlights the possible underlying mechanisms of the observed effects. Besides, novel formulations and improving pharmacokinetic properties may enhance the therapeutic efficacy of BAs.

Regulation of Apoptosis and Oxidative Stress by Oral Boswellia Serrata Gum Resin Extract in a Rat Model of Endometriosis.

Endometriosis (EMS) is a gynecological disease characterized by inflammation, oxidative stress, and apoptosis dysregulation. This study aims to evaluate the effect of Boswellia serrata gum resin extract (BS) on the endometriotic lesions in a rat model of endometriosis. We divided female rats into three groups, including Sham, EMS, EMS + BS. In the EMS and EMS + BS groups, pathology was induced and after 7 days by the abdominal high-frequency ultrasound (hfUS) analysis the presence of the endometriotic lesions was confirmed. Subsequently, the EMS + BS group was administered with BS (100 mg/Kg) daily for another 7 days. At the end of the experiment, the hfUS analysis was repeated and the animals were sacrificed to evaluate the size and histoarchitecture of the endometriotic implants. Pelvic ultrasound showed increased size of the endometriotic lesions in the Endo group, while BS administration reduced the lesion size. The macroscopic analysis confirmed the reduced area and volume of the endometriotic lesions of the EMS + BS group. The histological analysis showed reduced characteristic of ectopic stroma and glands in the animals treated with BS. Western blot analyses were conducted to evaluate the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. BS increases the expression of Nfr2 in the nucleus and the expression of its downstream antioxidant proteins NQO-1 and HO-1. Moreover, it reduced lipid peroxidation and increased glutathione (GSH) levels, and glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities. BS administration also restored the impaired apoptotic pathway in the lesions by reducing Bcl-2 expression and increasing Bax and cleaved caspase 9 levels. The BS apoptotic effect was also confirmed by the cleavage of PARP, another specific marker of apoptosis, and by the TUNEL assay. Our results show that BS administration resulted in an effective and coordinated suppression of Endo owing to its antioxidant and antiapoptotic activities.

Loureirin B protects against obesity via activation of adipose tissue ω3 PUFA-GPR120-UCP1 axis in mice.

Obesity and related metabolic disorders are worldwide epidemics. Current lifestyle interventions and drug treatment for obesity seem insufficient. Here, we show that Loureirin B (LB), a major flavonoid molecule extracted from Sanguis Draxonis, prevents diet-induced obesity and ameliorates concomitant metabolic abnormalities including fatty liver, insulin resistance and systemic inflammation in mice. Mechanistically, LB treatment increases the proportion of ω3 polyunsaturated fatty acids (PUFAs) in brown adipose tissue (BAT) and white adipose tissue (WAT), which subsequently activates the key lipid sensor GPR120. In line with this, LB treatment promotes browning of WAT and activates BAT thermogenesis through upregulation of UCP1, a downstream effector of GPR120. Conversely, inhibition of GPR120 abolishes the thermogenic effect of LB in primary cultured brown adipocytes. Together, these results suggest that LB possesses anti-obesity property by enhancing adipose tissue thermogenesis via activation of ω3 PUFA-GPR120-UCP1 axis and holds promises for combating obesity and its related metabolic syndrome.

The anti-inflammatory effect of myrrh ethanolic extract in comparison with prednisolone on an autoimmune disease rat model induced by silicate.

Autoimmune disease is a complex chronic disease that triggers immune activation against autoantigens resulting in tissue damage. Epidemiological data showed that autoimmune diseases are increasing worldwide over the last decades owing to increased environmental pollution. This study investigates the therapeutic effect of myrrh as a natural medicine compared to prednisolone in the treatment of immune-mediated glomerulonephritis induced by silicate. The autoimmune disease model in rats was induced by injecting 5 mg crystalline sodium silicate suspension subcutaneously once weekly for 20 weeks, and then the rats were treated either with myrrh extract or prednisolone or with both for 6 weeks. Liver and kidney function tests, histopathology, and immunohistochemistry of TNF-α expression in kidney tissue were performed. The creatinine significantly elevated in silica-treated group and decreased in other treated groups. Histopathology of the kidney revealed improvement of glomerular and tubular basement thickness in all treated groups, but the inflammatory cell count slightly decreased in the group treated with myrrh than the other treated groups which showed a marked decrease. TNF-α expression was significantly decreased in all treated groups. Interestingly, the myrrh did not produce hepatic lesions and improve the side effect of prednisolone in the liver when taken in combination. Therefore, myrrh extract possessed anti-inflammatory properties and counteracted the side effect of prednisolone on the liver. Myrrh extract can serve as a conjunctive therapy with prednisolone to treat autoimmune diseases.

Phytochemical Composition of Commiphora Oleogum Resins and Their Cytotoxicity against Skin Cancer Cells.

Oleogum resins of the genus Commiphora have been used in traditional medicines for centuries. More than 200 Commiphora species exhibit highly variable phytochemical compositions. A novel highly selective, sensitive, accurate HPLC-MS/MS method was developed and validated to quantify five characteristic phytosteroids and furanosesquiterpenoids, namely (E)-guggulsterone, (Z)-guggulsterone, curzerenone, furanoeudesma-1,3-diene, and myrrhone. The resulting contents and additionally GC analysis were used to classify and differentiate Commiphora oleogum resins of the species C. myrrha, C. erythraea, C. mukul, C. holtziana, C. confusa, and C. kua, as well as unspecified resins. Interestingly, a Commiphora sample from Ogaden, Ethiopia, comprised 446 ng/mg guggulsterones presumed to be unique to C. mukul from the Indian subcontinent. However, Commiphora from Ogaden differed considerably from C. mukul in respect to guggulsterones isomer's ratio. Moreover, the cytotoxicity of Commiphora extracts, essential oils, botanical drugs containing Commiphora, and pure compounds against the epidermoid carcinoma A431, malignant melanoma RPMI-7951 and SK-MEL-28 cells was investigated in vitro. Thereby, especially C. mukul extract and C. myrrha essential oil exhibited high cytotoxicity against skin cancer cells with IC50 of 2.9-10.9 µg/mL, but were less toxic to normal keratinocytes. In summary, Commiphora oleogum resins and its phytochemicals warrant further investigation aiming at chemotaxonomical classification as well as application in skin cancer treatment.

Chemistry and biological activity of resin glycosides from Convolvulaceae species.

Carbohydrate-based drug discovery has gained more and more attention during the last few decades. Resin glycoside is a kind of novel and complex glycolipids mainly distributed in plants of the family Convolvulaceae. Over the last decade, a number of natural resin glycosides and derivatives have been isolated and identified, and exhibited a broad spectrum of biological activities, such as cytotoxic, multidrug-resistant reversal on both microbial pathogens and mammalian cancer cells, antivirus, anticonvulsant, antidepressant, sedative, vasorelaxant, laxative, and α-glucosidase inhibitory effects, indicating their potential as lead compounds for drug discovery. A systematic review of the literature studies was carried out to summarize the chemistry and biological activity of resin glycosides from Convolvulaceae species, based on various data sources such as PubMed, Web of Science, Scopus, and Google scholar. The keyword "Convolvulaceae" was paired with "resin glycoside," "glycosidic acid," "glycolipid," or "oligosaccharide," and the references published between 2009 and June 2021 were covered. In this article, we comprehensively reviewed the structures of 288 natural resin glycoside and derivatives newly reported in the last decade. Moreover, we summarized the biological activities and mechanisms of action of the resin glycosides with pharmaceutical potential. Taken together, great progress has been made on the chemistry and biological activity of resin glycosides from Convolvulaceae species, however, more exploratory research is still needed, especially on the mechanism of action of the biological activities.

Dipterocarpol in Oleoresin of Dipterocarpus alatus Attributed to Cytotoxicity and Apoptosis-Inducing Effect.

Dipterocarpus alatus Roxb. ex G. Don is widely found in Southeast Asia. Its oleo-resin has reportedly been used in biodiesel production. Two different biodiesel production processes produce resinous byproducts, namely degumming (DG) and distillation (DT). Gas chromatography-mass spectrometry identified sesquiterpenes and triterpenes in oleo-resin, DG, and DT; and long-chain hydrocarbons in oleo-resin. High-performance liquid chromatography detected dipterocarpol as a marker compound, with the highest to lowest amounts detected in DG, DT, and oleo-resin, respectively. Oleo-resin, DG, and DT exerted more cytotoxicity than dipterocarpol, and melphalan, a chemotherapeutic drug. Oleo-resin, DG, and DT exerted cytotoxicity to a different degree in T cell leukemia (Jurkat), cervical adenocarcinoma (HeLa), and human hepatocellular carcinoma (HepG2) cells, while the highest selectivity was found in the Jurkat cells compared to the non-cancer Vero cells. Dipterocarpol exhibited the highest cytotoxicity in HepG2 cells and the lowest cytotoxicity in Jurkat cells. Oleo-resin, DG, and DT induced apoptosis in Jurkat cells. In oleo-resin, DG, and DT, dipterocarpol and other compounds may act in synergy leading to cytotoxicity and an apoptosis-inducing effect. Oleo-resin, DG, and DT could be potential sources for anticancer agents. Dipterocarpol could serve as a biomarker for follow ups on the anticancer activity of a sample from D. alatus.

Ferula assa-foetida oleo gum resin ethanolic extract alleviated the pancreatic changes and antioxidant status in streptozotocin-induced diabetic rats: A biochemical, histopathological, and ultrastructural study.

The current research examines the effects of administration of 150 and 250 mg/kg body weight/day of ethanolic Ferula assa-foetida L. oleo gum resin extract (FAE) for 42 days in streptozotocin-induced diabetes in rats. On day 42, all rats were euthanized; HOMA-ß, HOMA-IR, and QUICKI levels in pancreas were examined histopathologically and ultrastructurally . Low-dose FAE (150 mg/kg) treatment resulted in significant improvement in serum glucose, insulin and superoxide dismutase, glutathione, and catalase levels (p < .05). It also improved ß-cell function, restored pancreatic ß-cells, and reduced insulin resistance compared to the diabetic control rats. Necrotic and degenerative alterations in the islets, pyknotic ß-cell nuclei, ß-cell degranulation, reduced islet cellular density, and significant vacuolation were found in the islets of STZ-diabetic control group ratsby the histomorphological and ultrastructural examination. The pancreatic histomorphology of low dose of FAE-treated diabetic rats showed remarkable improvements in the islets, such as the ß-cell number and the area of the pancreatic islets. PRACTICAL APPLICATIONS: The experiment revealed that Ferula assa-foetida L. may exert antihyperglycemic activity in STZ diabetes via ß-cell regeneration and its high antioxidant capacity. This work elucidates the role of Ferula assa-foetida L. in diabetes management. Ferula assa-foetida L. gum extract improved the morphological changes of the diabetic pancreas and stimulated the regeneration of the ß cells. The findings demonstrated positive results for the long-term cure of diabetes. Additionally, this study showed the potential of isolating nutraceuticals for the development of medications.

In vivo wound healing effect of Italian and Algerian Pistacia vera L. resins.

Pistacia vera oleoresin is one of the natural products used traditionally for the management of wounds. However, there were no scientific reports documented so far on the wound healing activities to substantiate the claim. This study assesses the potential of the oleoresin of P. vera collected in Italy and Algeria for wound healing efficacy via in vivo circular wound excision model. Italian and Algerian oleoresins were subjected to purification and successive fractionation to obtain three matrices. The fractions have been characterized using GC-FID and GC-MS analyses. Oleoresins mixed with vaseline (5% w/w) were topically applied on wound excision induced on the dorsum of rabbits. Wound healing effects were evaluated by percent of wound contraction. Biopsies performed after healing were histologically assessed. Phytochemical results showed a high content of terpenoids components inducing an efficient wound healing effect determined by an in vivo study. Italian and Algerian oleoresins ointments showed significant wound contraction from day 8 to day 16 as compared to the negative control. The two ointments have not showed statistically difference as compared to Cicatryl, reference drug. These results have also been confirmed by the histological evaluation of the tissues involved. The absence of signs of toxicity on the skin of rabbits indicated the safety of the ointments. The study showed that both oleoresins have a very high effectiveness as wound healing agents and appear to justify their traditional use in wound healing in several countries and offer a scientific support to the treatment of traditional healers.

Overview of Chios Mastic Gum (Pistacia lentiscus) Effects on Human Health.

Despite the remarkable development of the medical industry in the current era, herbal products with therapeutic potentials arise as attractive alternative treatments. Consequently, Chios mastiha, a natural, aromatic resin obtained from the trunk and brunches of the mastic tree, has recently gained increasing scientific interest due to its multiple beneficial actions. Chios mastiha is being exclusively produced on the southern part of Chios, a Greek island situated in the northern Aegean Sea, and its therapeutic properties have been known since Greek antiquity. There is now substantial evidence to suggest that mastiha demonstrates a plethora of favorable effects, mainly attributed to the anti-inflammatory and anti-oxidative properties of its components. The main use of mastiha nowadays, however, is for the production of natural chewing gum, although an approval by the European Medicines Agency for mild dyspeptic disorders and for inflammations of the skin has been given. The aim of this article is to summarize the most important data about the therapeutic actions of Chios mastiha and discuss future fields for its medical application.

Effects of Oakmoss Components on Extra- and Intracellular Legionella pneumophila and Its Host Acanthamoeba castellanii.

Acanthamoeba castellanii is a ubiquitous organism found in environmental water. The amoeba is pathogenic to toward humans and is also a reservoir of bacteria of the genus Legionella, a causative agent of legionellosis. Oakmoss, a source of natural fragrance ingredients, and its components are antibacterial agents that are specifically active against the genus Legionella. In the present study, oakmoss and its components were investigated for their inhibitory effects on total (extra- and intracellular) Legionella pneumophila within A. castellanii and on L. pneumophila within A. castellanii. Among the oakmoss components, 3-hydroxy-5-methylphenyl 2,4-dihydroxy-6-methylbenzoate (1), 3-methoxy-5-methylphenyl 2,4-dihydroxy-6-methylbenzoate (2), and 8-(2,4-dihydroxy-6-(2-oxoheptyl)phenoxy)-6-hydroxy-3-pentyl-1H-isochromen-1-one (8) reduced the number of total bacteria (extra- and intracellular) in a test culture and also exhibited high amoebicidal activity against L. pneumophila within A. castellanii at concentrations lower than their IC50 values for A. castellanii. In contrast, 6,8-dihydroxy-3-pentyl-1H-isochromen-1-one (5) reduced the total number of L. pneumophila and, also that of total bacteria after 24 h of treatment (P < 0.05), whereas the compound did not exhibit amoebicidal activity against L. pneumophila within A. castellanii at concentrations lower than its IC50 value against A. castellanii. Thus, it is suggested that these oakmoss components could be good candidates for disinfectants to protect from Legionella infection.

Diverse Triterpenoids from Mastic Produced by Pistacia lentiscus and Their Anti-Inflammatory Activities.

Eight undescribed triterpenoids (1-8), including one apotirucallane-type triterpenoid (1), six tirucallane-type triterpenoids (2-7), and one oleanane-type triterpenoid (8), along with ten known compounds (9-18) were isolated from the resins of Pistacia lentiscus. Their structures were elucidated by integrating NMR spectroscopic analyses and ESI-HR-MS. Compounds 5, 11-17 exhibited moderate inhibitory abilities against NO production in LPS-induced RAW264.7 cells, with IC50 values in the range of 18.26-50.37 µM, compared to that of the positive control dexamethasone (IC50 =20.24 µM).

Isolation and Characterization of Two Chalcone Derivatives with Anti-Hepatitis B Virus Activity from the Endemic Socotraen Dracaena cinnabari (Dragon's Blood Tree).

Hepatitis B virus (HBV) infection is prevalent and continues to be a global health concern. In this study, we determined the anti-hepatitis B virus (HBV) potential of the Socotra-endemic medicinal plant Dracaena cinnabari and isolated and characterized the responsible constituents. A bioassay-guided fractionation using different chromatographic techniques of the methanolic extract of D. cinnabari led to the isolation of two chalcone derivatives. Using a variety of spectroscopic techniques, including 1H-, 13C-, and 2D-NMR, these derivatives were identified as 2,4'-dihydroxy-4-methoxydihydrochalcone (compound 1) and 2,4'-dihydroxy-4-methoxyhydrochalcone (compound 2). Both compounds were isolated for the first time from the red resin (dragon's blood) of D. cinnabari. The compounds were first evaluated for cytotoxicity on HepG2.2.15 cells and 50% cytotoxicity concentration (CC50) values were determined. They were then evaluated for anti-HBV activity against HepG2.2.15 cells by assessing the suppression of HBsAg and HBeAg production in the culture supernatants and their half maximum inhibitory concentration (IC50) and therapeutic index (TI) values were determined. Compounds 1 and 2 indicated inhibition of HBsAg production in a dose- and time-dependent manner with IC50 values of 20.56 and 6.36 µg/mL, respectively.