Essential oil of the leaves of Ricinus communis L.: in vitro cytotoxicity and antimicrobial properties

An inferior competitor is a successful invader due to its stress tolerance and productivity

The invasion of ecosystems by non-native species is recognized as one of the most significant global challenges, particularly in semiarid regions where native biodiversity is already under stress from drought and land degradation. The implicit assumption is that invaders are strong competitors, but a greenhouse pairwise experiment conducted to examine intraspecific and interspecific competition effects of Opuntia ficus-indica, a widespread invader in semiarid ecosystems, with two species native to the highlands of Eritrea, Ricinus communis and Solanum marginatum, revealed that O. ficus-indica is a weak competitor. The unique ability of O. ficus-indica's fallen cladodes to undergo vegetative growth becomes a fundamental trait contributing to its spread. This growth strategy allows O. ficus-indica to outgrow native species and establish a significant presence. In direct interaction, the competition in aboveground productivity measured by the logarithmic response ratio for O. ficus-indica was 3.4-fold and 5.9-fold higher than for R. communis and S. marginatum, respectively. Belowground, the native R. communis was facilitated (- 1.00 ± 0.69) by O. ficus-indica which itself suffered from high competition. This pattern became even more evident under water shortage, where aboveground competition for S. marginatum decreased 5.7-fold, and for O. ficus-indica, it increased 1.4-fold. Despite being a poor competitor, O. ficus-indica outperformed R. communis and S. marginatum in both aboveground (4.3 and 3.8 times more) and belowground (27 and 2.8 times more) biomass production, respectively. The findings of this study challenge the common interpretation that invasive species are strong competitors and highlight the importance of considering other factors, such as productivity and tolerance limits when assessing the potential impacts of invasive species on semiarid ecosystems.

The Antibacterial Effect of Tinospora Cordifolia (Guduchi) and Its Role in Combating Antimicrobial Resistance

Objective

Tinospora cordifolia, often known as "Guduchi," has a variety of medicinal characteristics, including those that are anti-diabetic, ant-iinflammatory, anti-periodic, anti-arthritic, anti-oxidant, anti-allergic, and anti-stress. Drug development projects face significant obstacles because of the rapid rise in antimicrobial drug resistance in the world healthcare system and the introduction of multidrug-resistant (MDR) strains. In order to combat the MDR infections isolated from patients' bodies, the current study was conducted to evaluate and investigate the antibacterial capabilities of Tinospora cordifolia.

Methods

Using the agar well diffusion method, Tinospora cordifolia extracts (aqueous, chloroform, and ethanol) were tested for their antibacterial effectiveness against 30 MDR pathogens, and the 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay was used to determine the minimal inhibitory concentration. To determine whether there were any medicinally useful and significant bioactive ingredients in the plant extract, phytochemical analysis was performed.

Results

In comparison to the aqueous extract which had little effect, the antibacterial activity of ethanol and chloroform extracts exhibited a potential antimicrobial effect against most of the tested bacterial isolates. Phytochemical analysis of Tinospora cordifolia extract showed alkaloids, carbohydrates, phytosterols, saponins, tannins, proteins, flavonoids, and terpenoids.

Conclusions

Our findings show that Tinospora cordifolia plays a potential role in combating the antimicrobial resistance of clinical isolates.

Poisonous Plants of the Indian Himalaya: An Overview

Indian Himalayan region (IHR) supports a wide diversity of plants and most of them are known for their medicinal value. Humankind has been using medicinal plants since the inception of civilization. Various types of bioactive compounds are found in plants, which are directly and indirectly beneficial for plants as well as humans. These bioactive compounds are highly useful and being used as a strong source of medicines, pharmaceuticals, agrochemicals, food additives, fragrances, and flavoring agents. Apart from this, several plant species contain some toxic compounds that affect the health of many forms of life as well as cause their death. These plants are known as poisonous plants, because of their toxicity to both humans and animals. Therefore, it is necessary to know in what quantity they should be taken so that it does not have a negative impact on health. Recent studies on poisonous plants have raised awareness among people who are at risk of plant toxicity in different parts of the world. The main aim of this review article is to explore the current knowledge about the poisonous plants of the Indian Himalayas along with the importance of these poisonous plants to treat different ailments. The findings of the present review will be helpful to different pharmaceutical industries, the scientific community and researchers around the world.

Microbial Deterioration of the Archaeological Nujoumi Dome (Egypt-Aswan): Identification and Suggested Control Treatments by Natural Products

Biodeterioration plays a significant role in the damage and loss of monuments including gypsum work. Bacteria and fungi are mainly responsible for the biodeterioration of gypsum work. Thus, the present study aimed to evaluate the effects of essential oils (Thyme, clove, cinnamon, garlic, castor, and olive) on the growth of the main fungi and bacteria which isolated from the Nujoumi Dome which is also called the Dome of the Toshka Martyrs and is located in Aswan, Egypt. Microbial swabs were taken from these infected objects, and the isolated microorganisms were characterized. The next genera were identified: four fungal isolates were isolated and identified as Aspergillus japonicas, Aspergillus terrus, Penicillium commune, and Cladosporium elatum while two species of bacteria were isolated, identified as Bacillus cereus and Listeria monocytogenes. Garlic oil had the best effect on all isolates, showing 35 and 33 mm inhibition of growth of Bacillus cereus and Listeria monocytogenes, respectively, while 28 mm inhabitation of growth of Penicillium commune, 25 mm inhibition of Aspergillus japonicas, and finally 20 mm inhibition of both Aspergillus terrus and Cladosporium elatum. In conclusion, garlic oil could be an effective natural product for controlling the biodeterioration.

Evaluation of larvicidal efficacy of Ricinus communis (Castor) and synthesized green silver nanoparticles against Aedes aegypti L

Aedes mosquitoes are the most important group of vectors that transmit pathogens, including arboviruses, and cause human diseases such as dengue fever, yellow fever, Zika virus, and Chikungunya. Biosynthesis and the use of green silver nanoparticles (AgNPs) is a vital step to identify reliable and eco-friendly controls for these vectors. In this study, Aedes (Ae.) aegypti larvae (2nd and 3rd instar) were exposed to leaf extracts of Ricinus communis (Castor) and AgNPs synthesized from the extract to evaluate their larvicidal potential. Synthesized AgNPs were characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (XRD). Ae. aegypti larvae were treated with different concentrations (50-250 ppm) of the leaf extract and synthesized AgNPs. There were five replicates per treatment, in addition to a positive (temephos) and negative control (dechlorinated water). Mortality was recorded after 12, 24, 36, and 48 h and the data were subjected to Probit analysis. The nanoparticles were more toxic (LC50 = 46.22 ppm and LC90 = 85.30 ppm) than the plant extract (106.24 and 175.73 ppm, respectively). The leaf extracts of Ricinus communis were subjected to HPLC analysis to identify their chemical constituents. This study suggests that plant extracts and synthesized nanoparticles are excellent alternatives to hazardous chemical pesticides used to control vector mosquitoes. This is a potentially useful technique that can reduce aquatic toxicity from insecticide use.

Mycelial form of dimorphic fungus Malassezia species dictates the microbial interaction

Dandruff is one of the most common clinically manifested and studied scalp disorders. It has been associated with both bacteria and fungi. Bacteria and fungi inhabiting the scalp are known to influence each other and manifestation of dandruff. Fungal and bacterial isolates from scalp epithelial flakes (dandruff) were identified by rDNA sequencing. Local oils were tested for fungal and bacterial inhibition, interaction and biofilm formation, cell-cell interactions were studied by auto aggregation and surface thermodynamics studies. The isolates Bacillus sp.C2b1 (MK036745) and Malassezia sp. C2y1 (MK036746) were inhibited by Mahabhrungraj oil. The fungal morphological switch was evident and dependent on nutrition. Cell aggregation studies suggested the interaction of bacteria with yeast (non-pathogenic) phase of the fungus. Bacterial and yeast cells were found to be compatible for biofilm formation. The fungal mycelial surfaces were found to be conducive for interaction with both bacterial cells and yeast forms. The results here indicate the significance of mycelial phase of scalp-isolated fungus in interaction with the bacterial surfaces and also with self-yeast phase surface. This is the first report of the interaction between scalp-isolated microorganisms with respect to their surface interaction capabilities.

Synthesis of Gold Nanoparticles (AuNPs) Using Ricinus communis Leaf Ethanol Extract, Their Characterization, and Biological Applications

The purpose of this study was to explore the collective biological properties of Ricinus communis ethanol leaf extract (RcExt) and extract-fabricated gold nanoparticles (RcExt-AuNPs). AuNPs were synthesized using RcExt. Fingerprint data of the biochemicals putatively found in RcExt were obtained using gas chromatography-mass spectrometry (GC-MS/MS) and high-performance liquid chromatography/ultraviolet-visible (HPLC/UV-VIS) analyses. RcExt-AuNPs were characterized by UV-Vis spectroscopy, scanning electron microscopy (SEM), and Fourier- transform infrared radiation (FTIR) spectroscopy. Cytotoxic activity on the Hela and HepG2 tumor cell lines was tested through cell viability, antimicrobial activity against bacterial and fungal pathogens through a well diffusion assay, hemolytic activity on red blood cells through absorbance reading, and stimulatory/inhibitory effects on splenic cells by cell viability. AuNPs of 200 nm size were synthesized. GC-MS/MS analysis revealed 12 peaks and HPLC/UV-VIS analysis resulted in 18, 13, and five peaks at the wavelengths of 220, 254, and 300 nm, respectively. Cytotoxicity screening revealed that RcExt had stimulatory effects (6.08%) on Hela cells and an inhibitory effect (-28.33%) on HepG2 cells, whereas RcExt-AuNPs showed inhibitory effects (-58.64% and -42.74%) on Hela and HepG2 cells, respectively. Antimicrobial activity of RcExt-AuNPs against tested pathogens was significantly higher (average diameters of inhibition zones were higher (ranging from 9.33 mm to 16.33 mm)) than those of RcExt (ranging from 6.00 mm to 7.33 mm). RcExt and RcExt-AuNPs showed 4.15% and 100% lytic effects, respectively. Inhibitory effects on splenic cells for RcExt-AuNPs were observed to be significantly higher (-30.56% to -72.62%) than those of RcExt (-41.55% to -62.25%) between concentrations of 25 to 200 µg/mL. RcExt-AuNPs were inhibitory against HepG2 and Hela cells, while RcExt inhibited HepG2 but stimulated Hela cells. RcExt-AuNPs showed comparatively more antimicrobial activity. RcExt was safe while RcExt-AuNPs harmful to red blood cells (RBCs). RcExt and RcExt-AuNPs showed inhibitory effects on splenic cells irrespective of dose.

Potential antidiabetic effect of ethanolic and aqueous-ethanolic extracts of Ricinus communis leaves on streptozotocin-induced diabetes in rats

Recently, herbal drugs and their bioactive compounds have gained popularity in the management of diabetes mellitus (DM), which has become an epidemic disease all over the world and is especially prevalent in the Kingdom of Saudi Arabia (KSA). This study aimed to investigate the antidiabetic effect of ethanolic and aqueous-ethanolic extracts of wild Ricinus communis (R. communis) leaves in streptozotocin (STZ) induced diabetic rats. Diabetic rats were administered orally with the mentioned extracts at doses of 300 and 600 mg/kg/BW for 14 days, and the obtained results of different biochemical parameters were compared with normal control, diabetic control and standard drug glibenclamide (5 mg/kg/BW). The obtained results revealed a remarkable and significantly (P < 0.05) reverse effect of the body weight loss, observed when diabetic rats were treated with ethanol and aqueous-ethanol extracts at 300 mg/kg/BW. Administration of the ethanol extract at 600 mg/kg/BW significantly (P < 0.05) reduced the blood glucose level. A significant increase in the AST, ALT and ALP levels (P < 0.05) was observed in the diabetic control and in the experimental groups with glibenclamide which was also significantly (P < 0.05) lowered after treatment with extracts at special doses. Total proteins, albumin, total bilirubin, direct bilirubin, creatinine and urea were also investigated and compared to the corresponding controls. We showed that administration of R. communis extract generally significantly (P < 0.05) ameliorated the biochemical parameters of diabetic rats. Also, the changes in serum electrolyte profile were assessed and the results demonstrate that administration of extracts at concentration of 600 mg/kg/BW generally inhibits the alteration maintain their levels. The obtained data imply the hypoglycemic effects of this plant, which may be used as a good alternative for managing DM and therefore validating its traditional usage in KSA.

Synthesis and characterization of Zinc oxide nanoparticles utilizing seed source of Ricinus communis and study of its antioxidant, antifungal and anticancer activity

ZnO nanoparticles have been synthesized using solution combustion technique and its antioxidant, antifungal, anticancer activity was studied. Ricinus communis plant seed extract used as fuel in synthesis by the solution combustion technique. Powder X-ray diffraction (PXRD) demonstrates the arrangement of a crystalline hexagonal stage (ICDD card number 89-1397) with space aggregate P63mc (186) and cell parameters a = b = 3.253, c = 5.213 Å. The normal crystallite measure is 20 nm which is ascertained by Debye - Scherer's formula. The Purity of the sample and metal to oxygen bond development was affirmed by utilizing Fourier transformation infrared (FTIR) spectroscopy and the particle size and shape was confirmed by HRTEM. Antifungal action of ZnO NPs was studied against Aspergillus and Penicillium by well dispersion strategy. The antifungal activity shows that ZnO NPs constitute as an effective fungicidal agent against both Aspergillus (4 ± 0.5 mm) and Penicillium (3 mm ± 0.4 mm) at 30 μg/mL fixation. ZnO nanoparticles were subjected to antioxidant activity. The objective of the study was to analyze the anticancer property of ZnO NPs on MDA-MB 231 cancer cells. To check the efficacy of the synthesized drug ZnO NPs MTT assay was performed, that determines % viability and/or cytotoxicity. IC₅₀ of ZnO NPs in case of MDA-MB-231 breast cancer was 7.103 μg/mL. Anticancer outcome demonstrates that ZnO NPs is active against in MDA-MB-231 cells.

In-vitro Activity of Trigonella foenum graecum Seeds Against a Clinical Strain of Acanthamoeba Genotype T4

Acanthamoeba keratitis (AK) is a sight-threatening infection of the cornea disease that often presents with a lengthy and not fully effective treatment. Current therapeutic options against Acanthamoeba are not very effective against the cyst. Calibrated trophozoite/cyst suspension was incubated with the same volume of serial dilutions of the Trigonella foenum graecum aqueous extract (200, 250, 350, 450, 600, and 750 mg/mL) in microcentrifuge tubes and mixed by pipetting up and down. After that, the tubes were incubated at 26 ºC for 24, 48, and 72 h. The obtained result revealed that incubation of the extract (at concentrations ranging from 200 to 750 mg/mL) with Acanthamoeba was able to decrease the number of viable trophozoites and cysts. In the presence of up to 450 mg/mL non-viable trophozoites were observed whereas cysts were only eliminated when incubated with 750 mg/mL of the extract after 24 h. Furthermore, no cytotoxicity of the extract even at the highest concentration tested in the study showed to be toxic for corneal cells. Further studies should be carried out in order to elucidate the active compounds involved in the observed anti-Acanthamoeba activities which could be used for the development of novel therapeutic approaches against Acanthamoeba infections.

An ethnopharmacological study of aromatic Uyghur medicinal plants in Xinjiang, China

CONTEXT

An ethnobotanical survey was completed in a remote village and surrounding country of Xinjiang, where most Uyghur medicinal plants could be collected. This work clarifies and increases ethnobotanical data.

OBJECTIVES

We surveyed and organized aromatic medicinal plants that are commonly used in clinical settings to provide a significant reference for studying new medical activities.

MATERIALS AND METHODS

In the survey, informants who have traditional knowledge on aromatic Uyghur medicinal plants were interviewed between March 2014 and September 2014. Aromatic medicinal plant species and pertinent information were collected. Some therapeutic methods and modes of preparation of traditional aromatic medicinal plants were found.

RESULTS

A total of 86 aromatic medicinal plant species belonging to 36 families were included in our study. We identified 34 plant species introduced from different regions such as Europe, India and Mediterranean areas. Fruits and whole plants were the most commonly used parts of plant, and most aromatic medicinal plants could be applied as medicine and food. We assigned the medicinal plants a use value (UV). Knowing the UV of species is useful in determining the use reliability and pharmacological features of related plants.

CONCLUSIONS

Xinjiang is an area in which indigenous aromatic medicinal plants are diversely used and has therefore established a sound dimensional medical healthcare treatment system. Some aromatic Uyghur medicinal plants are on the verge of extinction. Hence, further strategies for the conservation of these aromatic medicinal plants should be prioritized.

A review of Tunisian medicinal plants with anticancer activity

Cancer is a major public health problem in the world. The use of the medicinal plants in cancer prevention and management is frequent in Africa, especially in Tunisia, and it is transmitted from generation to generation within cultures. Many previous studies showed that a wide range of Tunisian medicinal plants exerted cytotoxic and anticancer activity. A comprehensive review was conducted to collect information from scientific journal articles, including indigenous knowledge researches, about Tunisian medicinal plants used for the prevention and management of cancer. The aim of this review article is to provide the reader with information concerning the importance of Tunisian medicinal plants in the prevention and management of cancer and to open the door for the health professionals and scientists working in the field of pharmacology and therapeutics to produce new drug formulations to treat different types of cancer.

Ethnopharmacological appraisal of culturally important medicinal plants and polyherbal formulas used against communicable diseases in Rodrigues Island

ETHNOPHARMACOLOGICAL RELEVANCE

The tropical island of Rodrigues is one of three islands that constitute the Mascarene archipelago in the Indian Ocean. Currently considered as a biodiversity hotspot, the island has also a resilient history in the use of traditional medicine. However, there has been no ethnopharmacological study to document quantitatively such traditional practice against communicable diseases (CD), which currently accounts for 6.61% annual death and 30.7% attendances in public hospitals. The aim of the present study was to collect, analyse, and document traditionally used medicinal plants (MP) and polyherbal formulas from key informants and traditional medicine practitioners (TMP) in Rodrigues to treat and/or manage common CD.

MATERIALS AND METHODS

Data was collected via face-to-face interviews with MP users (n=113) and TMP (n=9) from 17 key sites. Seven quantitative ethnopharmacological indices, namely family use value (FUV), use value (UV), informant agreement ratio (IAR), relative frequency of citation (RFC), fidelity level (FL), relative importance (RI), and ethnobotanicity index (EI) were calculated.

RESULTS

Ninety-seven plants belonging to 49 families were recorded to be in common use as monotherapy (80 plants) and/or as part of polyherbal preparation (23 plants) for the treatment and/or management of 16 different CD. Thirteen MPs were found to have a maximum FL of 100% for CD. The highest IAR (0.98) was observed for diseases of the eye and adnexa and skin and subcutaneous tissue. The highest FUV was for Arecaceae. Ayapana triplinervis (Vahl) R.M. king et H.Rob. scored the highest UV (UV=2.72). Seven endemic medicinal plants have been recorded to be employed in cultural rituals for the management of common CDs, whereas 14 polyherbal preparations were used to treat and/or manage 6 different types of CDs. Side effects were also reported following use of some these medicinal plants.

CONCLUSION

Given the dearth of updated information on traditional medicine from Rodrigues, this work has provided an opportunity to establish valuable primary information on the different MP used by the local people. Further research is needed to probe into the possible active constituents that could open new perspectives for further pharmacological research and hence be the basis of an evidence-based investigation to discover new drugs.

The use of medicinal herbs in gynecological and pregnancy-related disorders by Jordanian women: a review of folkloric practice vs. evidence-based pharmacology

Context National statistical reports in Jordan indicate a decrease in the total fertility rate along with a parallel increase in contraceptive use. The folkloric use of medicinal herbs in gynecological disorders has been growing in Jordan, despite of deficient reports on the evidence-based safety and efficacy of these practices. Objective The aim of this comprehensive article is to review medicinal plants with claimed ethnonpharmacological usage in various gynecological and pregnancy-related issues in Jordan, and to assess their evidence-based pharmacological studies as well as their phytochemistry. Methods The published literature was surveyed using Google Scholar entering the terms "ethnopharmacology AND Jordan AND infertility AND gynecology OR gestation". We included ethnopharmacological surveys in Jordan with available full-text. Results Twelve articles were reviewed. Plant species which are commonly used for female gynecological issues such as Artemisia monosperma Del. and A. herba-alba Asso. (Asteraceae) have been found to exert an antifertility effect. Ricinus communis L. (Euphorbiaceae) and Citrullus colocynthis (L.) Schrad. (Cucurbitaceae) had antifertility effects in male rats, but Nigella sativa oil L. (Ranunculaceae) and Cinnamon zeylanicum J. Presl (Lauraceae) were found to enhance it. Conclusion Using plants for gynecological disorders is a common practice in Jordan. Many of them, whether utilised for gynecological or non-gynecological conditions equally, were found to have detrimental effects on female or male fertility. Thus, couples planning pregnancy should be discouraged from the consumption of these herbs. Further local studies are warranted to confirm the appreciable beneficial pharmacological effects and safety of these plants.

Characterization and evaluation of antibacterial and antiproliferative activities of crude protein extracts isolated from the seed of Ricinus communis in Bangladesh

BACKGROUND

Ricinus communis (Euphorbiaceae) has previously been reported to possess analgesic, antihistamine, antioxidant and anti-inflammatory activities. This study was designed for isolation, characterization and evaluation of antibacterial and anti-proliferative activities of R. communis seed protein.

METHODS

The concentration and molecular weight of R. communis seed protein were estimated by SDS-PAGE and spectrophotometric analysis, respectively. Lectin activity was evaluated by hemagglutination assay on mice blood. In vitro susceptibility of four human pathogenic bacteria including Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes and Staphylococcus aureus was detected using disk diffusion assay, and minimum inhibitory concentration (MIC) value was determined using micro-dilution method. A total of twenty four Swiss albino mice containing Ehrlich's ascites carcinoma (EAC) cells were treated with the crude protein of R. communis at 50 and 100 μg/ml/d/mouse for 6 days. Growth inhibitory activity of R. communis seed protein on EAC cells was determined by haemocytometer counting using trypan blue dye and DAPI (4΄,6-diamidino-2-phenylindole) staining was used to assess apoptotic cells.

RESULTS

The protein concentration of six R. communis (castor) varieties ranged between 21-35 mg/ml and molecular weight between 14-200 kDa. Castor protein agglutinated mice blood at 3.125 μg/wall. The seed protein shows considerable antimicrobial activity against E. coli, P. aeruginosa and S. aureus, exhibiting MIC values of 250, 125 and 62.5 μg/ml, respectively. Administration of seed protein led to 54 % growth inhibition of EAC cells at 100 μg/ml. DAPI staining indicates marked features of apoptosis including condensation of cytoplasm, nuclear fragmentation and aggregation of apoptotic bodies etc.

CONCLUSION

Our study suggests that the lectin rich R. communis seed protein has strong antibacterial and anticancer activities.

Modification of sleep-waking and electroencephalogram induced by vetiver essential oil inhalation

Background:

Essential oils (EOs) have been claimed to modulate mental functions though the most of data were obtained from subjective methods of assessment. Direct effects of EO on brain function remained largely to be confirmed with scientific proof. This study aimed to demonstrate quantifiable and reproducible effects of commercial vetiver (Vetiveria zizanioides) EO inhalation on sleep-waking and electroencephalogram (EEG) patterns in adult male Wistar rats. The experiments were conducted during November 2013 - February 2014.

Materials and Methods:

The following electrode implantation on the skull, control, and treated animals were subjected for EEG recording while inhaling water and vetiver EO (20 and 200 µl), respectively. Fast Fourier transform was used for analysis of EEG power spectrum.

Results:

One-way ANOVA analysis confirmed that vetiver EO inhalation significantly increased total waking and reduced slow-wave sleep time. Moreover, EO inhalation decreased alpha and beta1 activity in both frontal and parietal cortices and increased gamma activity in the frontal cortex. Changes in these frequencies began almost from the start of the inhalation.

Conclusion:

These data suggest refreshing properties of vetiver EO on electrical brain activity and alertness.

Evaluation of leishmanicidal activity and cytotoxicity of Ricinus communis and Azadirachta indica extracts from western Kenya: in vitro and in vivo assays

BACKGROUND

Despite advances to targeted leishmanicidal chemotherapy, defies around severe toxicity, recent emergence of resistant variants and absence of rational vaccine still persist. This necessitates search and/or progressive validation of accessible medicinal remedies including plant based. The study examined both in vivo and in vitro response of L. major infection to combined therapy of Ricinus communis and Azadirachta indica extracts in BALB/c mice as the mouse model. A comparative study design was applied.

RESULTS

BALB/c mice, treated with combination therapy resulted in significantly (p < 0.05) larger reduction of lesion than those treated with monotherapies. The spleno-somatic index was found to be significantly low with combination therapy than monotherapies. Antiparasitic effect of A. indica and R. communis on amastigote with a 50 % inhibitory concentration (IC50) was of 11.5 and 16.5 µg mL(-1) respectively while combination therapy gave 9.0 µg ml(-1) compared to the standard drugs, Pentostam and amphotericin B which had an IC50 of 6.5 and 4.5 µg ml(-1) respectively. Optimal efficacy of A. indica and R. communis was 72 and 59.5 % respectively, combination therapy gave 88 %, while Pentostam and amphotericin B had 98 and 92 % respectively against amastigotes. Against promastigotes A. indica and R. Communis gave an IC50 of 10.1, 25.5 µg mL(-1) respectively, while combination, 12.2 µg mL(-1) against 4.1 and 5.0 µg ml(-1) for Pentostam and amphotericin B respectively. The optimal efficacy of the compounds against promastigotes was 78.0, 61.5 and 91.2 % (A. indica, R. communis and A. indica + R. communis respectively) against 96.5 and 98 % for Pentostam and amphotericin B respectively. The concentrations at optimal efficacy were significantly different (p < 0.05) among the test compounds. An evaluation of the IC50 values of the combination therapies clearly reveals synergistic effects.

CONCLUSION

Combination therapy of A. indica and R. communis had best antileishmanial activity than the monotherapies. The active ingredients of both R. communis and A. indica need to be fractionated, and studied further for activity against Leishmania parasites.

Ethnopharmacological analysis of medicinal plants used against non-communicable diseases in Rodrigues Island, Indian Ocean

ETHNOPHARMACOLOGICAL RELEVANCE

Rodrigues is an autonomous outer island that form part of the Republic of Mauritius and one of three islands that constitute the Mascarene archipelago in the Indian Ocean. Though herbal medicine is in common use in Rodrigues, there has been no ethnopharmacological study to document quantitatively such traditional practise particularly against non-communicable diseases (NCD) which is currently a growing major health issue on the island. The aim of the present study was to collect, analyse and document traditionally used medicinal plants (MP) from key informants and traditional medicine practitioners (TMP) in the tropical island of Rodrigues to treat and/or manage common NCD.

MATERIALS AND METHODS

Data was collected via face-to-face interviews with MP users (n=113) and TMP (n=9). Seven quantitative ethnopharmacological indices, namely family use value (FUV), use value (UV), informant agreement ratio (IAR), relative frequency of citation (RFC), fidelity level (FL), relative importance (RI) and ethnobotanicity index (EI) were calculated.

RESULTS

Hundred and three plants belonging to 55 families were recorded for the treatment and/or management of 27 different NCD. Three of the MP (Terminalia bentzoë (L.) L.F, Sarcostemma cf. adontolepis Balf.f. and Clerodendrum laciniatum Balf.f.) recorded are endemic to Rodrigues and 2 (Carissa xylopicron Thouars., Phyllanthus casticum Willemet f.) endemic to the Mascarene Islands. The most solicited MP family was Asteraceae with a total of 8 species. Citrus aurantifolia (Christm.) Swingle scored the highest RFC (RFC=1.02) value. Ten plants were found to score 100% FL and the highest IAR (0.98) was observed for the disease category of certain conditions originating in the perinatal period. Arecaceae scored the highest FUV value and Ayapana triplinervis (Vahl) R.M. King et H.Rob highest UV (UV= 2.72).

CONCLUSION

Given the dearth of updated information on traditional medicine of Rodrigues, this study can provide an opportunity to establish valuable primary information on the different MP used by the local people and hence can open new perspectives for further pharmacological research.

Ethnopharmacological analysis of medicinal plants and animals used in the treatment and management of pain in Mauritius

ETHNOPHARMACOLOGICAL RELEVANCE

Pain is a multi-faceted and multi-factorial condition which is challenging to manage and treat. Conventional therapies such as analgesics, Non-steroidal anti-inflammatory drugs (NSAIDs), and corticosteroids amongst others have been successful to some extent in its management and treatment. Nonetheless, such therapies tend to be accompanied by undesirable effects and have a limited therapeutic range. Consequently, there is a pressing need to probe for novel analgesic and anti-nociceptive drugs from traditional medicines (TM). This study was designed to record, document and analyze herbal and animal-based therapies used for the management and treatment of pain in the tropical of Mauritius.

MATERIALS AND METHODS

Data was collected via face-to-face interviews with TM users (n=332) and practitioners (n=20). Seven quantitative ethnopharmacological indexes, namely family use value (FUV), use value (UV), informant agreement ratio (IAR), relative frequency of citation (RFC), fidelity level (FL), relative importance (RI) and ethnobotanicity index (EI) were calculated.

RESULTS

A total of 79 plant species distributed within 40 families and 20 polyherbal preparations was recorded. Interestingly, 6 indigenous/endemic plants have been reported for the first time to be in common use for pain management and treatment in Mauritius. The most significant biologically important plant family was Xanthorrhoeaceae with highest FUV. The species which ranked highest according to its UV was Morinda citrifolia L. Morinda citrifolia L. and Ricinus communis L. also scored the highest RFC. The IAR values for the disease categories were high (0.95-0.97). Based on EI, plants species which are known to be useful in TM accounted for 11.5% of the total flora in Mauritius. Coix lacryma-jobi L. (FL=100%) had highest FL for lower back ache. Morinda citrifolia L. scored highest on most of the quantitative indices calculated including RI, which is endorsed by extensive documentation on its versatility and particularly its anti-nociceptive properties. Seven animal species were recorded to be in common use.

CONCLUSION

The present ethnopharmacological study revealed a panoply of TM to be in common use for pain management and treatment in Mauritius. This study has documented for the first time medicinal plants and animal species with potential analgesic and/or anti-nociceptive properties. This study has therefore provided important baseline primary data for the discovery of new lead molecules for drug development geared towards pain management and treatment.

In Vitro Assessment of Cytotoxicity, Antioxidant, and Anti-Inflammatory Activities of Ricinus communis (Euphorbiaceae) Leaf Extracts

Ricinus communis has been utilized traditionally as medicine to treat inflammatory related diseases including wounds, sores, and boils. The leaves of R. communis were sequentially extracted with n-hexane, dichloromethane, acetone, and methanol using serial exhaustive extraction method. Antioxidant activity of all crude extracts was quantitatively measured against 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical molecules using ABTS⁺ assay. Cytotoxic effect and anti-inflammatory activity of R. communis leaves extracts were evaluated on Human Caucasian skin fibroblast and Raw 264.7 macrophage cell lines, respectively. Methanol extract had the highest percentage free radical (ABTS⁺) scavenging activity of 95% at 2.50 mg/mL, acetone 91%, dichloromethane 62%, and hexane the least (50%). Percentage scavenging activity of ABTS⁺ free radical molecules increases with increase in concentrations of the plant extracts. Hexane and dichloromethane extracts had more than 90% cell viability at 100 µg/mL after 24 and 48 hours of exposure. Methanol extract had LC₅₀ of 784 µg/mL after 24-hour exposure, hexane had 629.3 µg/mL and dichloromethane 573.6 µg/mL, and 544.6 µg/mL was the lowest with acetone extract. The study present the first report on the scavenging activity of R. communis leaf extracts against ABTS⁺ radicals and cytotoxic effects on human Caucasian skin fibroblast cell lines.