Phytochemical screening and antiviral activity of some medicinal plants from the island Soqotra

Antiviral Potential and Chemical Composition of Wild Baccharis crispa Spreng. Populations (Asteraceae) from Córdoba, Argentina: Perspective on Population Variability

Medicinal plants have been explored worldwide as potential alternatives for the prevention and treatment of different diseases, including viral infections. Baccharis crispa Spreng. (Asteraceae) is a native medicinal species widely used in South America. Given the influence of genetic and environmental factors on secondary metabolites biosynthesis and accumulation, this study aimed to evaluate the in vitro antiviral activity of four wild populations of B. crispa from Córdoba, Argentina, and assess the variability in their bioactivity and chemical composition. The cytotoxicity of chloroform, ethanol, and aqueous extracts from aerial parts was evaluated by the neutral red uptake method. Antiviral and virucidal activity against herpes simplex virus type 1 (HSV-1) and chikungunya virus (CHIKV) were assessed via plaque-forming unit (PFU) reduction assay. Phytochemical analyses of the extracts were conducted using HPLC-ESI- MS/MS. The Puesto Pedernera population showed the strongest antiviral activity, with inhibition rates of 82% for CHIKV and 79% against HSV-1, as well as potent virucidal effects, reducing PFU formation by up to 5 logarithms for both viruses. Remarkably, ethanol extract exhibited the least toxicity and strongest inhibitory activity. Villa del Parque population was inactive. We identified 38 secondary metabolites, predominantly phenolic acids (12) and flavonoids (18), in varying proportions. Delphinidin and delphinidin-3-glucoside are described for the first time in the species. Differences in phytochemical profiles were observed among extract types and populations. Key phenolic compounds showed moderate positive correlations with the evaluated bioactivities, emphasizing the complexity of phytochemical properties and interactions. These results highlight the therapeutic potential of B. crispa extracts against viral infections and underscore the importance of considering the geographical source of plant material in bioactivity evaluations.

Cytotoxic and antiviral activities of Jatropha variegata and Jatropha spinosa in relation to their metabolite profile

Jatropha variegata and Jatropha spinosa (family: Euphorbiaceae) are utilized in Yemeni traditional medicine to treat respiratory tract infection and in different skin conditions such as wound healing, as antibacterial and hemostatic. In this study, we evaluated the cytotoxicity and the antiviral activities of the methanolic J. variegata (leaves: Ext-1, stems: Ext-2, and roots: Ext-3), and J. spinosa extracts (aerial parts: Ext-4 and roots: Ext-5), in addition to their methylene chloride fractions of roots extracts (F-6 and F-7, respectively). All samples were tested against three human cancer cell lines in vitro (MCF-7, HepG2, and A549) and two viruses (HSV-2 and H1N1). Both plants showed significant cytotoxicity, among them, the methylene chloride fractions of roots of J. variegata (F-6) and J. spinosa roots (F-7) showed the highest activity on MCF-7 (IC50 = 1.4 and 1 μg/mL), HepG2 (IC50 = 0.64 and 0.24 μg/mL), and A549 (IC50 = 0.7 and 0.5 μg/mL), respectively, whereas the IC50 values of the standard doxorubicin were (3.83, 4.73, and 4.57 μg/mL) against MCF-7, HepG2, and A549, respectively. These results revealed that the roots of both plants are potential targets for cytotoxic activities. The in vitro results revealed potential antiviral activity for each of Ext-3, Ext-5, F-6, and F-7 against HVS-2 with IC50 of 101.23, 68.83, 4.88, 3.24 μg/mL and against H1N1 with IC50 of 51.29, 27.92, 4.24, and 3.06 μg/mL respectively, whereas the IC50 value of the standard acyclovir against HVS-2 was 83.19 μg/mL and IC50 value of the standard ribavirin against H1N1 was 52.40 μg/mL .The methanol extracts of the roots (Ext-3 and Ext-5) of both plants were characterized using UPLC/MS. A total of 73 metabolites were annotated, including fourteen diterpenoids, eleven flavonoids, ten phenolic acid conjugates, twelve fatty acids and their conjugates, five triterpenes and steroids, two sesquiterpenes, and six coumarins. The cytotoxicity and antiviral activities determined in the present work are explained by the existence of flavonoids, coumarins and diterpenes with commonly known cytotoxicity and antiviral activities.

Role of phytocompounds as the potential anti-viral agent: an overview

Viral diseases are the most notorious infective agent(s) causing morbidity and mortality in every nook and corner for ages; viruses are active in host cells, and specific anti-virus medicines' developments remain uncanny. In this century of the biological era, human viruses act predominantly as versatile spreaders. The infection of the present COVID-19 virus is up in the air; blithely, the integument of medicinal chemistry approaches, particularly bioactive derived phytocompounds could be helpful to control those human viruses, recognized in the last 100 years. Indeed, natural products are being used for various therapeutic purposes. The major bioactive phytocompounds are chemically containing coumarin, thiosulfonate, steroid, polysaccharide, tannin, lignin, proanthocyanidin, terpene, quinone, saponin, flavonoid, alkaloid, and polyphenol, that are documented for inhibitory action against several viral infections. Mostly, about 20-30% of plants from tropical or temperate regions are known to have some antiviral activity. This comprehensive analysis of bioactive-derived phytocompounds would represent a significant impact and might be helpful for antiviral research and the current state of viral treatments.

Effects of Boswellia species on viral infections with particular attention to SARS-CoV-2

The emergence of pathogenic viruses is a worldwide frequent cause of diseases and, therefore, the design of treatments for viral infections stands as a significant research topic. Despite many efforts, the production of vaccines is faced with many obstacles and the high rate of viral resistance caused a severe reduction in the efficacy of antiviral drugs. However, the attempt of developing novel natural drugs, as well as the exertion of medicinal plants, may be an applicable solution for the treatment of viral diseases. Boswellia species exhibited a wide range of pharmacological activities in various conditions such as bronchial asthma, rheumatism, and Crohn’s illness. Additionally, pharmacological studies reported the observance of practical antiviral activities from different parts of this substance, especially the oleo-gum-resin. Therefore, this work provided an overview on the antiviral properties of Boswellia species and their potential therapeutic effects in the field of COVID-19 pandemic.

Binding of boswellic acids to functional proteins of the SARS-CoV-2 virus: Bioinformatic studies

Boswellic acids (BAs) have been shown to possess antiviral activity. Using bioinformatic methods, it was tested whether or not acetyl‐11‐keto‐β‐boswellic acid (AKBA), 11‐keto‐β‐boswellic acid (KBA), β‐boswellic acid (BBA), and the phosphorylated active metabolite of Remdesivir® (RGS‐P3) bind to functional proteins of SARS‐CoV‐2, that is, the replicase polyprotein P0DTD1, the spike glycoprotein P0DTC2, and the nucleoprotein P0DTC9. Using P0DTD1, AKBA and KBA showed micromolar binding affinity to the RNA‐dependent RNA polymerase (RdRp) and to the main proteinase complex M^pro. Phosphorylated BAs even bond in the nanomolar range. Due to their positive and negative charges, BAs and RGS‐P3 bond to corresponding negative and positive areas of the protein. BAs and RGS‐P3 docked in the tunnel‐like cavity of RdRp. BAs also docked into the elongated surface rim of viral M^pro. In both cases, binding occurred with active site amino acids in the lower micromolecular to upper nanomolar range. KBA, BBA, and RGS‐P3 also bond to P0DTC2 and P0DTC9. The binding energies for BAs were in the range of −5.8 to −6.3 kcal/mol. RGS‐P3 and BAs occluded the centrally located pore of the donut‐like protein structure of P0DTC9 and, in the case of P0DTC2, RGS‐P3 and BAs impacted the double‐wing‐like protein structure. The data of this bioinformatics study clearly show that BAs bind to three functional proteins of the SARS‐CoV‐2 virus responsible for adhesion and replication, as does RGS‐P3, a drug on the market to treat this disease. The binding effectiveness of BAs can be increased through phosphate esterification. Whether or not BAs are druggable against the SARS‐CoV‐2 disease remains to be established.

Phytochemistry and Pharmacological Activities of Dracaena cinnabari Resin

Dracaena cinnabari (D. cinnabari) is an endemic plant located in Socotra Island, Yemen. Deep red resin attained from different plant species including D. cinnabari is commonly known as dragon's blood. In folk medicine, it is prescribed for the treatment of traumatic dermal, dental, and eye injuries as well as blood stasis, pain, and gastrointestinal diseases in humans. Numerous studies have investigated that this resinous medicine has antidiarrheal, antiulcer, antimicrobial, antiviral, antitumor, anti-inflammatory, analgesic, wound healing, and antioxidant activity. Several phytochemicals have been isolated from D. cinnabari, including the biflavonoid cinnabarone, triflavonoids, metacyclophanes, chalcones, chalcanes, dihydrochalcones, sterols, and terpenoids. The present review highlights the structures and bioactivities of main phytochemicals isolated from D. cinnabari regarding the botany and pharmacological effects of the resin derived from this plant.

Supramolecular self-assembly of amantadine hydrochloride with ferulic acid via dual optimization strategy establishes a precedent of synergistic antiviral drug-phenolic acid nutraceutical cocrystal

To display the capability of the phenolic acid nutraceutical ferulic acid (FLA) in optimizing the in vitro/in vivo properties of the antiviral drug amantadine hydrochloride (AMH) and achieve synergistically enhanced antiviral effects, thereby gaining some new insights into pharmaceutical cocrystals of antiviral drugs with phenolic acid nutraceuticals, a cocrystallization strategy of dual optimization was created. Based on this strategy, the first drug-phenolic acid nutraceutical cocrystal of AMH with FLA, namely AMH-FLA-H2O, was successfully assembled and completely characterized by employing single-crystal X-ray diffraction and other analytical techniques. The cocrystal was revealed to be composed of AMH, FLA, and water molecules in the ratio of 3 : 1 : 1.5, and charge-assisted hydrogen bonds containing chloride ions crucially maintained the crystal lattice together with water molecules. The in vitro/in vivo properties of the cocrystal were systematically evaluated via both theoretical and experimental methods, and the results indicate that the dissolubility of AMH is down-regulated by two-thirds in the cocrystal, resulting in its potential for sustained pharmacokinetic release and the elimination of the adverse effects of AMH. More importantly, the enhanced antiviral effects of the current cocrystal were proven against four viral strains, and the pharmaceutical synergy between AMH and FLA was realized with a combination index (CI) of less than 1. Thus, the present work provides a novel crystalline product with bright commercial prospect for the classical antiviral drug AMH and also establishes an avenue for the synergetic antiviral application of nutraceutical phenolic acids via the cocrystallization strategy of dual optimization.

Review of Whole Plant Extracts With Activity Against Herpes Simplex Viruses In Vitro and In Vivo

Herpes simplex viruses, HSV-1 and HSV-2, are highly contagious and cause lifelong, latent infections with recurrent outbreaks of oral and/or genital lesions. No cure exists for HSV-1 or HSV-2 infections, but antiviral medications are commonly used to prevent and treat outbreaks. Resistance to antivirals has begun to emerge, placing an importance on finding new and effective therapies for prophylaxis and treatment of HSV outbreaks. Botanicals may be effective HSV therapies as the constituents they contain act through a variety of mechanisms, potentially making the development of antiviral resistance more challenging. A wide variety of plants from different regions in the world have been studied for antiviral activity against HSV-1 and/or HSV-2 and showed efficacy of varying degrees. The purpose of this review is to summarize research conducted on whole plant extracts against HSV-1 and/or HSV-2 in vitro and in vivo. The majority of the research reviewed was conducted in vitro using animal cell lines, and some studies used an animal model design. Also summarized are a limited number of human trials conducted using botanical therapies on HSV lesions.

A new homoisoflavan from Dracaena cinnabari Balf. f. resin: α-glucosidase and COX-II inhibitory activity

A new homoisoflavan, identified as (3 R)-7-hydroxy-3',4'-methylenedioxyhomoisoflavan, was isolated from Dracaena cinnabari Balf. f. resin. The structure was elucidated by one- and two-dimensional NMR spectroscopy as well as high resolution mass spectrometry. In addition, a diverse group of flavonoids were isolated, representing homoisoflavans, flavans, flavanones, chalcones and dihydrochalcones. The compounds were evaluated for their α-glucosidase and COX-II inhibition activity. The obtained IC₅₀ values of the tested flavonoids gave an insight about some key structural features to their α-glucosidase and COX-II inhibitory activity. For α-glucosidase inhibitory activity, a flavanone skeleton was favorable over a flavan. For COX-II inhibition, the introduction of a fused heterocyclic ring at the homoisoflavan skeleton enhanced the activity.

Molecular adduct of amantadine ferulate presents a pathway for slowing in vitro/vivo releases and raising synergistic antiviral effects via dual optimization salification strategy

The first synthesized antiviral drug-nutriment molecular salt demonstrating simultaneous slowed-release and synergistically enhanced antiviral effects is studied theoretically and experimentally.

Punica protopunica Balf., the Forgotten Sister of the Common Pomegranate (Punica granatum L.): Features and Medicinal Properties-A Review

Punica protopunica Balf. is one of only two species housed by the Punica genera. Punica protopunica. Balf., known as Socotran pomegranate, is an endemic, isolated species found only in Socotra archipelago in the northwestern Indian Ocean, and is considered to be the ancestor of pomegranate. This review stems from the fact that in many Punica granatum L. articles, Punica protopunica Balf. is mentioned, but just in an informative way, without mentioning their taxonomic and genetic relationship and their medicinal properties. It is there where the need arises to know more about this forgotten species: “the other pomegranate tree.” A large part of the human population does not know of its existence, since only its “sister” has spread throughout the world. The present review deals with the taxonomy and origin of Punica protopunica Balf., the morphology of the tree, distribution, cultivation, vulnerability, and as well as its relationship with Punica granatum L. It also discusses its uses in traditional medicine, its antioxidant capacity, and the medicinal properties of this forgotten species.

First screening report of immune and protective effect of non-toxic Jatropha vernicosa stem bark against Vibrio parahaemolyticus in Longfin yellowtail Seriola rivoliana leukocytes

In México, the infusion of Jatropha vernicosa stem bark has been used in folk medicine for many clinical situations, but no reports were available about this particular species of Jatropha in fish of mammals. In this first screening report, the phytochemical, antioxidant profile and antimicrobial properties of aqueous J. vernicosa stem bark extract were explored against Vibrio parahaemolyticus, an opportunist fish pathogen. To evaluate the cytotoxicity and immunological effect for the possible application of aqueous J. vernicosa stem bark in aquaculture, this study assessed it by using Longfin yellowtail Seriola rivoliana leukocytes. The results showed that phytochemical composition of the J. vernicosa extract was rich in phenol, flavonoid, saponin, and coumarin compounds. The antioxidant capacity of hydroxyl radical and superoxide anion scavenging activities, iron-chelation activity and β-carotene bleaching coupled to linoleic acid showed that J. vernicosa extracts had a moderate antioxidant effect compared with synthetic antioxidants (BHT, BHA and EDTA). No adverse effects were observed on spleen leukocytes (viability > 98%). Interestingly, J. vernicosa stem bark extract has immunostimulant and antioxidant effects, increasing phagocytosis, respiratory burns activity, and nitric oxide production, as well as superoxide dismutase and catalase activities. Additionally, J. vernicosa extract increased pro-inflammatory cytokine IL-1β and suppressed anti-inflammatory IL-10 gene expression upon stimuli and V. parahaemolyticus challenge. Finally, the data confirms that J. vernicosa stem bark extract is non-cytotoxic, rich in bioactive compounds with antioxidant effects, capable of enhancing the immune system in leukocytes and with great potential to fight against opportunistic diseases, such as vibriosis in fish.

Triterpenic Acids as Non-Competitive α-Glucosidase Inhibitors from Boswellia elongata with Structure-Activity Relationship: In Vitro and In Silico Studies

Fourteen triterpene acids, viz., three tirucallane-type (1-3), eight ursane-type (4-11), two oleanane-type (12, 13) and one lupane type (21), along with boswellic aldehyde (14), α-amyrine (15), epi-amyrine (16), straight chain acid (17), sesquiterpene (19) and two cembrane-type diterpenes (18, 20) were isolated, first time, from the methanol extract of Boswellia elongata resin. Compound (1) was isolated for first time as a natural product, while the remaining compounds (2‒21) were reported for first time from B. elongata. The structures of all compounds were confirmed by advanced spectroscopic techniques including mass spectrometry and also by comparison with the reported literature. Eight compounds (1-5, 11, 19 and 20) were further screened for in vitro α-glucosidase inhibitory activity. Compounds 3-5 and 11 showed significant activity against α-glucosidase with IC₅₀ values ranging from 9.9-56.8 μM. Compound 4 (IC₅₀ = 9.9 ± 0.48 μM) demonstrated higher inhibition followed by 11 (IC₅₀ = 14.9 ± 1.31 μM), 5 (IC₅₀ = 20.9 ± 0.05 μM) and 3 (IC₅₀ = 56.8 ± 1.30 μM), indicating that carboxylic acid play a key role in α-glucosidase inhibition. Kinetics studies on the active compounds 3-5 and 11 were carried out to investigate their mechanism (mode of inhibition and dissociation constants K_i). All compounds were found to be non-competitive inhibitors with K_i values in the range of 7.05 ± 0.17-51.15 ± 0.25 µM. Moreover, in silico docking was performed to search the allosteric hotspot for ligand binding which is targeted by our active compounds investigates the binding mode of active compounds and it was identified that compounds preferentially bind in the allosteric binding sites of α-glucosidase. The results obtained from docking study suggested that the carboxylic group is responsible for their biologic activities. Furthermore, the α-glucosidase inhibitory potential of the active compounds is reported here for the first time.

Antiviral activity and chemical characterization of Cissus erosa (Vitaceae) ethanol extracts

Abstract Cissus erosa (Vitaceae), popularly known in Brazil as Cipó-fogo, is a medicinal plant used in the treatment of warts and external ulcers. The present study aimed to evaluate the activity of stems and leaves ethanol extracts of C. erosa against the Dengue and Zika virus by the MTT colorimetric method and to carry on the phytochemical characterization of active extracts by high performance liquid chromatography coupled to mass spectrometry (UPLC-MS). Only the leaves ethanol extract showed anti-Dengue virus activity EC50 18.2 µg/ml (SI > 27.5) and low cytotoxicity for LLCMK2 cells (CC50 > 500 mg/ml). Both extracts (stems and leaves) showed anti-Zika virus activity with EC50 of 45.8 mg/ml and 82.8 mg/ml, respectively. These extracts presented CC50 of 309.2 µg/ml (leaves) and 387.6 µg/ml (stems) to Vero cells. Analysis by CCD and HPLC-DAD detected the presence of triterpenes, steroids, flavonoids and tannins. UPLC-MS analyses of these extracts, allowed the identification of the majority of flavonoids present known as vitexin, isovitexin, orientin, isoorientin and two flavones derivatives, methoxyluteolin-6(8)-C-hexosyl and luteolin-7,4’-di-O-glycosylflavone. The results of the phytochemical studies here described suggest that flavonoids and terpenoids are the substances that contribute to the antiviral activity of the ethanol extracts within this species.

The in vitro and in vivo antitumor effects of Dracaena cinnabari resin extract on oral cancer

OBJECTIVE

To study the potential for apoptosis induction of Dracaena cinnabari Balf. f methanolic extract (DCBME) on tongue squamous cell carcinoma cell line, H103. We evaluated the chemopreventive activity of DCBME against 4-nitroquinolone-1-oxide (4NQO)-induced tongue carcinogenesis in rat.

DESIGN

Phase contrast microscope, acridine orange/propidium iodide (AO/PI) analysis of cells under fluorescence microscope, annexin-V flow-cytometry, DNA fragmentation, mitochondrial membrane potential, and caspase 3/7, 8 and 9 assays were performed. In vivo study, the rats were given 4NQO in their drinking water. The tongue was subjected to histopathological study to evaluate the incidence of squamous cell carcinoma (SCC).

RESULTS

DCBME showed cytotoxic effect on H103 cells in a dose- and time-dependent manner. Furthermore, DCBME showed low cytotoxic effect on a normal cell line. In H103 cells, it caused cell morphology changes, S and G2/M-phase cell cycle arrest, significant reduction of cell migration and induced apoptosis through the intrinsic (mitochondrial) pathway. The incidence of SCC was 85.7% in the induced cancer and vehicle groups while in rats treated with DCBME at 100, 500 and 1000 mg/kg was 57.1%, 28.6% and 14.3%, respectively.

CONCLUSIONS

(DCBME)-apoptosis induction reported in this work can be exploited as a potential antitumor agent with applications in medicinal treatments of tongue SCC.

Acute and sub-acute oral toxicity of Dracaena cinnabari resin methanol extract in rats

BACKGROUND

Dracaena cinnabari (DC) is a perennial tree that located on the Southern coast of Yemen native to the Socotra Island. This tree produces a deep red resin known as the Dragon's blood, the Twobrother's Blood or Damm Alakhwain. The current study performed to evaluate the safety of the DC resin methanol extract after a single or 28 consecutive daily oral administrations.

METHODS

In assessing the safety of DC resin methanol extract, acute and sub-acute oral toxicity tests performed following OECD guidelines 423 and 407, respectively, with slight modifications. In acute oral toxicity test, DC resin methanol extract administered to female Sprague Dawley rats by oral gavage at a single dose of 300 and 2000 mg/kg body weight. Rats observed for toxic signs for 14 days. In sub-acute oral toxicity test, DC resin methanol extract administered to the rats by oral gavage at 500, 1000, and 1500 mg/kg body weight daily up to 28 days to male and female Spradgue Dawley rats. The control and high dose in satellite groups were also maintained and handled as the previous groups to determine the late onset toxicity of DC resin methanol extract. At the end of each test, hematological and biochemical analysis of the collected blood were performed as well as gross and microscopic pathology.

RESULTS

In acute oral toxicity, no treatment-related death or toxic signs were observed. It revealed that the DC resin methanol extract could be well tolerated up to the dose 2000 mg/kg body weight and could be classified as Category 5. The sub-acute test observations indicated that there are no treatment-related changes up to the high dose level compared to the control. Food consumption, body weight, organ weight, hematological parameters, biochemical parameters and histopathological examination (liver, kidney, heart, spleen and lung) revealed no abnormalities. Water intake was significantly higher in the DC resin methanol extract treated groups compared to the control.

CONCLUSION

This study demonstrates tolerability of DC resin methanol extract administered daily for 28 days up to 1500 mg/kg dose.

Boswellic Acids and Their Role in Chronic Inflammatory Diseases

Boswellic acids, which are pentacyclic triterpenes belong to the active pharmacological compounds of the oleogum resin of different Boswellia species. In the resin, more than 12 different boswellic acids have been identified but only KBA and AKBA received significant pharmacological interest. Biological Activity: In an extract of the resin of Boswellia species multiple factors are responsible for the final outcome of a therapeutic effect, be it synergistic or antagonistic. Moreover, the anti-inflammatory actions of BAs are caused by different mechanisms of action. They include inhibition of leukotriene synthesis and to a less extend prostaglandin synthesis. Furthermore inhibition of the complement system at the level of conversion of C3 into C3_a and C3_b. A major target of BAs is the immune system. Here, BEs as well as BAs including KBA and AKBA, have been shown to decrease production of proinflammatory cytokines including IL-1, IL-2, IL-6, IFN-γ and TNF-α which finally are directed to destroy tissues such as cartilage, insulin producing cells, bronchial, intestinal and other tissues. NFĸB is considered to be the target of AKBA. The complex actions of BEs and BAs in inflamed areas may be completed by some effects that are localized behind the inflammatory process as such tissue destruction. In this case, in vitro- and animal studies have shown that BAs and BEs suppress proteolytic activity of cathepsin G, human leucocyte elastase, formation of oxygen radicals and lysosomal enzymes.

PHARMACOKINETICS

Whereas KBA is absorbed reaching blood levels being close to in vitro IC_50, AKBA which is more active in in vitro studies than KBA, but undergoes much less absorption than KBA. However, absorption of both is increased more than twice when taken together with a high-fat meal.Clinical Studies There are a variety of chronic inflammatory diseases which respond to treatment with extracts from the resin of Boswellia species. Though, the number of cases is small in related clinical studies, their results are convincing and supported by the preclinical data. These studies include rheumatoid arthritis, osteoarthritis, chronic colitis, ulcerative colitis, collagenous colitis, Crohn's disease and bronchial asthma. It can not be expected that there is cure from these diseases but at least improvement of symptoms in about 60-70 % of the cases. Side Effects The number and severity of side effects is extremely low. The most reported complaints are gastrointestinal symptoms. Allergic reactions are rare. And most authors report, that treatment with BEs is well tolerated and the registered side effects in BE- and placebo groups are similar.

Antiviral activities of aerial subsets of Artemisia species against Herpes Simplex virus type 1 (HSV1) in vitro

Background: Drug resistance to current anti-herpetic drugs has been increasingly reported. Therefore, there is a need for finding new antiviral agents, in particular from natural sources.

Objective: In the present study, antiviral activity of subset extracts obtained from aerial parts of Artemisia including A. incana, A. chamaemelifolia, A. campesteris, A. fragrans, A. annua, A. vulgaris, and A. persica were investigated against Herpes Simplex type I (HSV1).

Methods: Different concentrations of extracts (400, 200, 100, 50, 25, 12.5, 6.25, and 3.125 μg/mL) were obtained from subset of each plant separately, and used against KOS strain of HSV1 in HeLa cells. After 24 hours incubation, tetrazolium dye (MTT), was added. The dye absorption by viable cells was measured and compared to the positive control (extract-untreated cells) and acyclovir (as anti-viral agent).

Results: The extracts obtained from A. annua had the highest antiviral activity while those of A. chamaemelifolia showed the lowest activity.

Conclusion: Subset extracts of A. annua may be an appropriate candidate for further development of anti HSV1 infection.

Menorrhagia Management in Iranian Traditional Medicine

Menorrhagia is a common problem. Medical management for menorrhagia includes hormonal and nonhormonal treatments. These treatments have different side effects, which reduce quality of life. Complementary and traditional medicines have been used to handle menorrhagia for centuries in many cultures. There is a lot of information and data in Iranian traditional documents or books about medicinal herbs that are used by Iranian traditional medicine scientists for the treatment of menorrhagia. The aim of this study was to review the approaches to menorrhagia in Iranian traditional medicine texts. In this study, some main Iranian traditional medicine manuscripts including Canon of Medicine and Al-Havi of Rhazes were studied to extract important information about menorrhagia management. Iranian traditional medicine physicians have relied on an organized system of etiological theories and treatments for menorrhagia. Their methods for menorrhagia management may be able to convince the desire of many women to preserve their uterus and avoid hormonal therapy.

The globalization of traditional medicine in northern peru: from shamanism to molecules

Northern Peru represents the center of the Andean "health axis," with roots going back to traditional practices of Cupisnique culture (1000 BC). For more than a decade of research, semistructured interviews were conducted with healers, collectors, and sellers of medicinal plants. In addition, bioassays were carried out to evaluate the efficacy and toxicity of plants found. Most of the 510 species encountered were native to Peru (83%). Fifty percent of the plants used in colonial times have disappeared from the pharmacopoeia. Market vendors specialized either on common and exotic plants, plants for common ailments, and plants only used by healers or on plants with magical purposes. Over 974 preparations with up to 29 different ingredients were used to treat 164 health conditions. Almost 65% of the medicinal plants were applied in these mixtures. Antibacterial activity was confirmed in most plants used for infections. Twenty-four percent of the aqueous extracts and 76% of the ethanolic extracts showed toxicity. Traditional preparation methods take this into account when choosing the appropriate solvent for the preparation of a remedy. The increasing demand for medicinal species did not increase the cultivation of medicinal plants. Most species are wild collected, causing doubts about the sustainability of trade.

Medicinal property, phytochemistry and pharmacology of several Jatropha species (Euphorbiaceae): a review

The genus Jatropha (Euphorbiaceae) comprises of about 170 species of woody trees, shrubs, subshrubs or herbs in the seasonally dry tropics of the Old and the New World. They are used in medicinal folklore to cure various diseases of 80% of the human population in Africa, Asia and Latin America. Species from this genus have been popular to cure stomachache, toothache, swelling, inflammation, leprosy, dysentery, dyscrasia, vertigo, anemia, diabetis, as well as to treat HIV and tumor, opthalmia, ringworm, ulcers, malaria, skin diseases, bronchitis, asthma and as an aphrodisiac. They are also employed as ornamental plants and energy crops. Cyclic peptides alkaloids, diterpenes and miscellaneous compounds have been reported from this genus. Extracts and pure compounds of plants from this genus are reported for cytotoxicity, tumor-promoting, antimicrobial, antiprotozoal, anticoagulant, immunomodulating, anti-inflammatory, antioxidant, protoscolicidal, insecticidal, molluscicidal, inhibition AChE and toxicity activities.

Assessment of the in vitro antiprotozoal and cytotoxic potential of 20 selected medicinal plants from the island of Soqotra

Malaria, leishmaniasis and human African trypanosomiasis continue to be major public health problems in need of new and more effective drugs. The aim of this study was to evaluate in vitro antiprotozoal activity of twenty endemic medicinal plants collected from the island of Soqotra in the Indian Ocean. The plant materials were extracted with methanol and tested for antiplasmodial activity against erythrocytic schizonts of Plasmodium falciparum, for antileishmanial activity against intracellular amastigotes of Leishmania infantum and for antitrypanosomal activity against intracellular amastigotes of Trypanosoma cruzi and free trypomastigotes of T. brucei. To assess selectivity, cytotoxicity was determined against MRC-5 fibroblasts. Selective activity was obtained for Punica protopunica against Plasmodium (IC₅₀ 2.2 µg/mL) while Eureiandra balfourii and Hypoestes pubescens displayed activity against the three kinetoplastid parasites (IC₅₀ < 10 µg/mL). Acridocarpus socotranus showed activity against T. brucei and T. cruzi (IC₅₀ 3.5 and 8.4 µg/mL). Ballochia atrovirgata, Dendrosicycos socotrana, Dracaena cinnabari and Euphorbia socotrana displayed non-specific inhibition of the parasites related to high cytotoxicity.

Antiviral Ability of Kalanchoe gracilis Leaf Extract against Enterovirus 71 and Coxsackievirus A16

Pandemic infection or reemergence of Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) occurs in tropical and subtropical regions, being associated with hand-foot-and-mouth disease, herpangina, aseptic meningitis, brain stem encephalitis, pulmonary edema, and paralysis. However, effective therapeutic drugs against EV71 and CVA16 are rare. Kalanchoe gracilis (L.) DC is used for the treatment of injuries, pain, and inflammation. This study investigated antiviral effects of K. gracilis leaf extract on EV71 and CVA16 replications. HPLC analysis with a C-18 reverse phase column showed fingerprint profiles of K. gracilis leaf extract had 15 chromatographic peaks. UV/vis absorption spectra revealed peaks 5, 12, and 15 as ferulic acid, quercetin, and kaempferol, respectively. K. gracilis leaf extract showed little cytotoxicity, but exhibited concentration-dependent antiviral activities including cytopathic effect, plaque, and virus yield reductions. K. gracilis leaf extract was shown to be more potent in antiviral activity than ferulic acid, quercetin, and kaempferol, significantly inhibiting in vitro replication of EV71 (IC(50) = 35.88 μg/mL) and CVA16 (IC(50) = 42.91 μg/mL). Moreover, K. gracilis leaf extract is a safe antienteroviral agent with the inactivation of viral 2A protease and reduction of IL-6 and RANTES expressions.

In vitro antiviral activities of extracts derived from Daucus maritimus seeds

The antiviral activities of extracts from Daucus maritimus seeds were investigated against the reverse transcriptase of human immunodeficiency virus (HIV) type 1 and a panel of RNA-dependent RNA polymerases of dengue virus, West Nile virus (WNV) and hepatitis C virus (HCV). The extracts showed moderate to potent inhibition rates against the four viral polymerases. The ethyl acetate extract exhibited a potent inhibitory effect against WNV's RdRp, with an IC₅₀ value of 8 µg mL⁻¹. The F₂ fraction exhibited potent inhibitory activity against WNV and HCV's RdRps, with IC₅₀ values 1 and 5 µg mL⁻¹, respectively. The P₂ fraction also showed potent inhibitory effects on WNV and HCV's RdRps, with IC₅₀ values 2.7 and 4 µg mL⁻¹, respectively. The results suggest that these extracts are candidates for the development of new anti-WNV RpDp and anti-HCV RpDp agents.

Bioprotective properties of Dragon's blood resin: in vitro evaluation of antioxidant activity and antimicrobial activity

Background

Food preservation is basically done to preserve the natural characteristics and appearance of the food and to increase the shelf life of food. Food preservatives in use are natural, chemical and artificial. Keeping in mind the adverse effects of synthetic food preservatives, there is a need to identify natural food preservatives. The aims of this study were to evaluate in vitro antioxidant and antimicrobial activities of Dragon's blood resin obtained from Dracaena cinnabari Balf f., with a view to develop safer food preservatives.

Methods

In this study, three solvents of varying polarity were used to extract and separate the medium and high polarity compounds from the non-polar compounds of the Dragon's blood resin. The extracts were evaluated for their antimicrobial activity against the food borne pathogens. The antioxidant activities of the extracts were assessed using DPPH and ABTS radical scavenging, FRAP, metal chelating and reducing power assays. Total phenolics, flavonoids and flavonols of extracts were also estimated using the standard methods.

Results

Phytochemical analysis of extracts revealed high phenolic content in CH₂Cl₂ extract of resin. Free radical scavenging of CH₂Cl₂ extract was found to be highest which is in good correlation with its total phenolic content. All test microorganisms were also inhibited by CH₂Cl₂ extract.

Conclusions

Our result provide evidence that CH₂Cl₂ extract is a potential source of natural antioxidant compounds and exhibited good inhibitory activity against various food borne pathogens. Thus, CH₂Cl₂ extract of Dragon's blood resin could be considered as possible source of food preservative.

Endophytic fungi from Dragon's blood specimens: isolation, identification, phylogenetic diversity and bioactivity

Endophytic fungi from Dragon's blood specimens of different locations of China were characterized taxonomically and investigated concerning their antimicrobial and antitumor activity against six pathogenic microbes and five tumor cells. A total of 49 endophytic fungi were obtained from Dragon's blood materials of Dracaena spp., 18 taxa were represented by 43 (87.8%) isolates and only six (12.2%) isolates were unknown. Twenty (40.8%) of the isolates displayed antimicrobial activity against at least one pathogenic microorganism. Three isolates YNDC07, BJDC06 and BJDC09 displayed significant antimicrobial activities against Staphylococcus aureus, Cryptococcus neoformans and Aspergillus fumigates, respectively. The results of antitumor activity by the MTT assay revealed that 26.5%, 69.4%, 48.9%, 6.1% and 42.9% of isolate fermentation broths displayed growth inhibition on HepG2 cells, SKVO3 cells, MCF7 cells, HL-60 cells and 293-T cells, respectively. HNDC09 and HNDC10 showed very strong antitumor activity against MCF7 and 293-T, respectively. The results showed that endophytic fungi in Dragon's blood samples were valuable in screening antitumor and antimicrobial bioactivity agents.

Production of dragon's blood in Dracaena cochinchinensis plants by inoculation of Fusarium proliferatum

Dragon's blood is a traditional medicine widely used in the world from ancient times. However, little is known about its formation mechanism. This work aimed to gain some insights into its formation mechanism and to control its production. The results demonstrate that wounding plus causal fungal infection and keeping the wound moist are essential for efficient dragon's blood formation in Dracaena cochinchinensis. Two fungal isolates YM-266 and YM-71213 of Fusarium proliferatum increased the yield of dragon's blood in D. cochinchinensis trees by 2.7- and 3.3-times compared to that of the control (wounding alone and keeping the wound moist), respectively. The fungal induced dragon's blood had almost identical chemical constituents to that of the natural dragon's blood with a higher loureirins a and b content as analyzed by TLC and HPLC. In addition, the induced dragon's blood had similar antimicrobial activity and similar or higher antioxidant activity than that of the natural dragon's blood. The novel biological technology developed here for the production of dragon's blood is safe, repeatable, practical, and feasible for the farmers, enabling the production of dragon's blood in a sustainable way without destroying the endangered trees and environment.

Assessment of selected Yemeni medicinal plants for their in vitro antimicrobial, anticancer, and antioxidant activities

CONTEXT

The role of natural products as a source for remedies has been recognized since the beginning of mankind. Nevertheless, a minority of folkloricly used medicinal plants have been evaluated for their pharmacological activities.

OBJECTIVES

The purpose of this study is to evaluate 33 selected Yemeni plants for their in vitro anticancer, antimicrobial, and antioxidant activities.

MATERIALS AND METHODS

The plants were extracted with methanol and hot water. The obtained 66 extracts were tested for their in vitro cytotoxic activity using the neutral red uptake assay against two cancer cell lines (5637 and MCF-7). The antimicrobial activity was determined using the agar diffusion method and MIC-determination. The DPPH radical method was used for the determination of antioxidant activity.

RESULTS

Interesting cytotoxic activity was observed for Hypoestes forskalei (Vahl) R. Br. (Acanthaceae), Lycium shawii Roem. & Schult. (Solanaceae), Pergularia tomentosa L. (Asclepiadaceae), Psiadia punctulata (DC.) Vatke (Compositae), Pulicaria petiolaris Jaub. & Spach (Compositae) and Rosmarinus officinalis L. (Labiatae) (IC(50) values < 50 μg/mL). Antimicrobial activity with MIC values ≤ 125 μg/mL was exhibited against Gram-positive bacteria by Chrozophora oblongifolia (Del.) A.Juss. ex Spreng. (Euphorbiaceae), Myrtus communis L. (Myrtaceae), Phragmanthera regularis (Steud. ex Sprague) M.G. Gilbert (Loranthaceae) and R. officinalis. Antioxidant activity was observed for C. oblongifolia, M. communis, and P. regularis.

CONCLUSION

The results justified the use of some investigated plants in the Yemeni ethnomedicine. These findings demonstrated that some of the investigated plants could be a source of new cytotoxic and antibiotic compounds; however, further work is needed.

Chemical analysis and biological activity of the essential oils of two endemic Soqotri Commiphora species

The barks of two endemic Commiphora species namely, Commiphora ornifolia (Balf.f.) Gillett and Commiphora parvifolia Engl., were collected from Soqotra Island in Yemen and their essential oils were obtained by hydrodistillation. The chemical composition of both oils was investigated by GC and GC-MS. Moreover, the essential oils were evaluated for their antimicrobial activity against two Gram-positive bacteria, two Gram-negative bacteria and one yeast species by using a broth micro-dilution assay for minimum inhibitory concentrations (MIC) and for their antioxidant activity by measuring the DPPH radical scavenging activity. A total of 45 constituents of C. ornifolia (85.6%) and 44 constituents of C. parvifolia (87.1%) were identified. The oil of C. ornifolia was characterized by a high content of oxygenated monoterpenes (56.3%), of which camphor (27.3%), α-fenchol (15.5%), fenchone (4.4%) and borneol (2.9%) were identified as the main components. High contents of oxygenated sesquiterpenes (36.1%) and aliphatic acids (22.8%) were found in C. parvifolia oil, in which caryophyllene oxide (14.2%), β-eudesmol (7.7%), bulnesol (5.7%), T-cadinol (3.7%) and hexadecanoic acid (18.4%) predominated. The results of the antimicrobial assay showed that both oils exhibited moderate to high antibacterial activity especially against Gram-positive bacteria. C. ornifolia oil was the most active. In addition, the DPPH-radical scavenging assay exhibited only weak antioxidant activities for both oils at the high concentration tested.

Studies of the in vitro anticancer, antimicrobial and antioxidant potentials of selected Yemeni medicinal plants from the island Soqotra

Background

Recent years have witnessed that there is a revival of interest in drug discovery from medicinal plants for the maintenance of health in all parts of the world. The aim of this work was to investigate 26 plants belonging to 17 families collected from a unique place in Yemen (Soqotra Island) for their in vitro anticancer, antimicrobial and antioxidant activities.

Methods

The 26 plants were extracted with methanol and hot water to yield 52 extracts. Evaluation for in vitro anticancer activity was done against three human cancer cell lines (A-427, 5637 and MCF-7) by using an established microtiter plate assay based on cellular staining with crystal violet. Antimicrobial activity was tested against three Gram-positive bacteria, two Gram-negative bacteria, one yeast species and three multiresistant Staphylococcus strains by using an agar diffusion method and the determination of MIC against three Gram-positive bacteria with the broth micro-dilution assay. Antioxidant activity was investigated by measuring the scavenging activity of the DPPH radical. Moreover, a phytochemical screening of the methanolic extracts was done.

Results

Notable cancer cell growth inhibition was observed for extracts from Ballochia atro-virgata, Eureiandra balfourii and Hypoestes pubescens, with IC₅₀ values ranging between 0.8 and 8.2 μg/ml. The methanol extracts of Acanthospermum hispidum, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia and Euphorbia socotrana also showed noticeable antiproliferative potency with IC₅₀ values < 50 μg/ml. The greatest antimicrobial activity was exhibited by extracts from Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana, Commiphora ornifolia, Euclea divinorum, Euphorbia socotrana, Leucas samhaensis, Leucas virgata, Rhus thyrsiflora, and Teucrium sokotranum with inhibition zones > 15 mm and MIC values ≤ 250 μg/ml. In addition, the methanolic extracts of Acacia pennivenia, Boswellia dioscorides, Boswellia socotrana and Commiphora ornifolia showed good antioxidant potential at low concentrations (more than 80% at 50 μg/ml).

Conclusion

Our results show once again that medicinal plants can be promising sources of natural products with potential anticancer, antimicrobial and antioxidative activity. The results will guide the selection of some plant species for further pharmacological and phytochemical investigations.

Boswellic acids: a group of medicinally important compounds

This review, containing over 276 references, covers the progress made in the chemistry and bioactivity of this important group of triterpenoids. Though initially known for their anti-inflammatory and anti-arthritic activities through a unique 5-LO inhibition mechanism, boswellic acids have recently attained significance due to their anti-cancer properties. The phytochemistry and chemical modifications, including mechanism of action, are discussed.

Dragon's blood: botany, chemistry and therapeutic uses

Dragon's blood is one of the renowned traditional medicines used in different cultures of world. It has got several therapeutic uses: haemostatic, antidiarrhetic, antiulcer, antimicrobial, antiviral, wound healing, antitumor, anti-inflammatory, antioxidant, etc. Besides these medicinal applications, it is used as a coloring material, varnish and also has got applications in folk magic. These red saps and resins are derived from a number of disparate taxa. Despite its wide uses, little research has been done to know about its true source, quality control and clinical applications. In this review, we have tried to overview different sources of Dragon's blood, its source wise chemical constituents and therapeutic uses. As well as, a little attempt has been done to review the techniques used for its quality control and safety.

Antimicrobial, antioxidant and cytotoxic activities and phytochemical screening of some yemeni medicinal plants

The traditional medicine still plays an important role in the primary health care in Yemen. The current study represents the investigation of 16 selected plants, which were collected from different localities of Yemen. The plants were dried and extracted with two different solvents (methanol and hot water) to yield 34 crude extracts. The obtained extracts were tested for their antimicrobial activity against three Gram-positive bacteria, two Gram-negative bacteria, one yeast species and three multiresistant Staphylococcus strains using agar diffusion method, for their antioxidant activity using scavenging activity of DPPH radical method and for their cytotoxic activity using the neutral red uptake assay. In addition, a phytochemical screening of the methanolic extracts was done. Antibacterial activity was shown only against Gram-positive bacteria, among them multiresistant bacteria. The highest antimicrobial activity was exhibited by the methanolic extracts of Acalypha fruticosa, Centaurea pseudosinaica, Dodonaea viscosa, Jatropha variegata, Lippia citriodora, Plectranthus hadiensis, Tragia pungens and Verbascum bottae. Six methanolic extracts especially those of A. fruticosa, Actiniopteris semiflabellata, D. viscosa, P. hadiensis, T. pungens and V. bottae showed high free radical scavenging activity. Moreover, remarkable cytotoxic activity against FL-cells was found for the methanolic extracts of A. fruticosa, Iris albicans, L. citriodora and T. pungens. The phytochemical screening demonstrated the presence of different types of compounds like flavonoids, terpenoids and others, which could be responsible for the obtained activities.

Ethnomedicines and ethnomedicinal phytophores against herpesviruses

Herpesviruses are important human pathogens that can cause mild to severe lifelong infections with high morbidity in susceptible adults. Moreover, Herpes simplex virus (HSV) type 2, for example, has been reported to be responsible for increased transmission and disease progression of human immunodeficiency virus (HIV). Therefore, the discovery of novel anti-HSV drugs deserves great efforts. Herbal medicinal products have been used as source of putative candidate drugs in many diseases. However, in case of viral diseases the development of antivirals from natural source is less explored probably because within the virus there are few specific targets where the small molecules can interact to inhibit or kill the virus. The currently available antiherpes drugs are nucleoside analogs that did not cure the lifelong or recurrent infections and the use of these drugs often lead to the development of viral resistance coupled with the problem of side effects, recurrence and viral latency. However a wide array of herbal products, used by diverse medicinal systems throughout the world, showed high level of antiherpesvirus activities and many of them have complementary and overlapping mechanism of action, either by inhibiting viral replication, or viral genome synthesis. This chapter will summarize some of the promising herbal extracts and purified compounds isolated from the herbal sources by several laboratories. Cases with proven in vitro and documented in vivo activities, along with their structure-activity relationship against herpesviruses are discussed.

Antiviral potentials of medicinal plants

Medicinal plants have been widely used to treat a variety of infectious and non-infectious ailments. According to one estimate, 25% of the commonly used medicines contain compounds isolated from plants. Several plants could offer a rich reserve for drug discovery of infectious diseases, particularly in an era when the latest separation techniques are available on one hand, and the human population is challenged by a number of emerging infectious diseases on the other hand. Among several other ailments, viral infections, particularly infections associated with human immunodeficiency virus type 1 (HIV-1) and 2 (HIV-2), and newly emerging infectious viruses have challenged mankind survival. Of importance, a variety of medicinal plants have shown promise to treat a number of viral infections, and some of them possess broad-spectrum antiviral activity. In the past, exploration into the antiviral activity of various promising medicinal plants was limited due to: (a) highly infectious nature of viruses and (b) lack of appropriate separation techniques for the identification of antiviral components from plants. Development of vector-based strategies, in which non-infectious molecular clone of a virus could be used for antiviral screening purposes, and advancement in separation technologies offers promise for medicinal plants usage in modern drug discovery. This article describes potential antiviral properties of medicinal plants against a diverse group of viruses, and suggests screening the potential of plants possessing broad-spectrum antiviral effects against emerging viral infections.

Antiviral activity of some plants used in Nepalese traditional medicine

Methanolic extracts of 41 plant species belonging to 27 families used in the traditional medicine in Nepal have been investigated for in vitro antiviral activity against Herpes simplex virus type 1 (HSV-1) and influenza virus A by dye uptake assay in the systems HSV-1/Vero cells and influenza virus A/MDCK cells. The extracts of Astilbe rivularis, Bergenia ciliata, Cassiope fastigiata and Thymus linearis showed potent anti-herpes viral activity. The extracts of Allium oreoprasum, Androsace strigilosa, Asparagus filicinus, Astilbe rivularis, Bergenia ciliata and Verbascum thapsus exhibited strong anti-influenza viral activity. Only the extracts of A. rivularis and B. ciliata demonstrated remarkable activity against both viruses.

Screening of traditionally used endemic Soqotraen plants for cytotoxic activity

Thirty extracts obtained from 10 endemic plant species belonging to 8 plant families used in the traditional medicine in Socotra have been tested for cytotoxic activity against FL-cells. Extracts of Eureiandra balfourii and Commiphora ornifolia showed the strongest activity against FL-cells with IC(50) < 10 microg/ml and 39.3 microg/ml respectively.