Larvicidal effects of mineral turpentine, low aromatic white spirits, aqueous extracts of Cassia alata, and aqueous extracts, ethanolic extracts and essential oil of betel leaf (Piper betle) on Chrysomya megacephala.
Sujith Prasad W Kumarasinghe, Nadira D Karunaweera, Ranjan L Ihalamulla, Lakshmi S R Arambewela, Roshinie D S C T Dissanayake
Colombo North Teaching Hospital, Ragama, Sri Lanka. firstname.lastname@example.org
BACKGROUND Many methods have been employed, with variable success, in the treatment of cutaneous myiasis caused by Chrysomya species. AIMS Experiment 1: to assess the larvicidal effect of mineral turpentine (MT) and the main ingredient of MT, low aromatic white spirits (LAWS), on Chrysomya megacephala larvae in vitro. Experiment 2: to assess the larvicidal effects of aqueous extracts of winged senna (Cassia alata), and aqueous extracts, ethanolic extracts and essential oil of betel leaf (Piper betle). METHODS In experiment 1, two samples of LAWS were obtained from two industrialists (samples 1 and 2). Adult flies of C. megacephala were bred in the insectory of the Department of Parasitology, Faculty of Medicine, University of Colombo. Petri dishes were prepared with pads of cotton wool. These cotton pads were soaked separately in MT, LAWS samples 1 and 2, and normal saline as a control. Ten larvae were placed in each Petri dish. The activity of the larvae was observed and recorded half-hourly. MT and the two samples of LAWS were analyzed by chromatography. In experiment 2, volatile essential oil of betel was prepared using a standard steam distillation process. An ethanolic extract of betel was obtained after boiling the crushed leaf with water, and mixing the stock with ethanol. Betel oil dilutions of 1-4% were prepared using 1% Tween 80 (v/v aq) as a solvent, with 0.05 g/100 mL sodium lauryl sulphate (as stabilizer) and 0.01 g/100 mL methyl paraben (as a preservative). Cotton wool swabs soaked in 1, 2, 3 and 4% essential oil of betel in 1% Tween 80 (v/v aq) prepared as above, 1, 2, 3 and 4% ethanolic extract of betel, 50 and 25% aqueous extract of C. alata, and 50 and 25% aqueous extract of betel were placed in separate Petri dishes. Ten larvae were placed in each Petri dish. 1% Tween 80 solvent with the stabilizer and the preservative, but without betel essential oil, was used as a negative control and MT was used as a positive control. Larval motility was assessed as before. RESULTS MT and the two LAWS samples killed the larvae in vitro within 4 h. Chromatography showed more unidentified constituents in MT than in pure LAWS, indicating additional substances in MT. The 4 and 3% preparations of the essential oil of betel were effective in killing 100% of the larvae of Chrysomya within 3 h 30 min. The 2% extract of betel essential oil killed 96.7% of larvae in 4 h. Ethanolic and aqueous extracts of betel, the aqueous extract of C. alata, normal saline and the Tween 80 solvent were not larvicidal. CONCLUSIONS MT and LAWS, the main ingredient of MT, were effective in killing Chrysomya larvae. Essential oil obtained from betel leaves also showed a dose-dependent larvicidal effect on Chrysomya larvae. This natural product may be effective in the treatment of wound myiasis.
L S R Arambewela, L D A M Arawwawala, K G Kumaratunga, D S Dissanayake, W D Ratnasooriya, S P Kumarasingha
Industrial Technology Institute, Bauddhaloka Mawatha, Colombo 7, Sri Lanka (currently at Royal Perth Hospital, Perth, Australia).
Piper betle is an economically important plant cultivated in Sri Lanka. Although more than 12 cultivars of betel are reported in Sri Lanka, very few scientific investigations have been carried out on them. Studies on the chemical constituents indicated that safrole is the major constituent, followed by chavibitol acetate, in the essential oil of common betel leaves of Sri Lanka. Investigations on the bioactivities of P. betle revealed the presence of antimicrobial, insecticidal, antioxidant, antinociceptive, antidiabetic and gastroprotective activities. In addition, P. betle was found to be safe in terms of hepatotoxicity, renotoxicity, hematotoxicity, gross morphology, weights of organs, stress or aversive behaviors in rats. The above findings indicate the vast potential of P. betle yet to be harnessed for the benefit of mankind and the betel industry of Sri Lanka.
Laboratoire de Pharmacognosie, E.A. 1043, Université de Lille 2, Faculté de Pharmacie B.P. 83, 59006 Lille cedex (France).
A review is made of chemical, ethnopharmacological and pharmacological papers dealing with Senna alata (L.) Roxb., a plant that belongs to the Creole traditional system of medicine and that has recently been introduced in the French Pharmacopoeia. The proofs existing for its various usages are presented. The species is mainly used against constipation and skin diseases. The laxative activity is supported by scientific findings. In contrast the dermatologic use requires further investigation. The species can be considered as safe for short-term or topical use.
The insecticidal activity of four medicinal plants against the blowfly Lucilia sericata (Diptera: Calliphoridae).
Department of Parasitology, Faculty of Veterinary Medicine, Benha University, Moshtohor, Egypt. email@example.com
BACKGROUND The larvae of Lucilia sericata induce myiasis and transmit mycobacterial infections to humans and animals. Consequently, the blowfly should be controlled for human welfare and economic reasons. METHODS The insecticidal effect of fenugreek (Trigonella foenum-graecum), celery (Apium graveolens), radish (Raphanus sativus), and mustard (Brassica compestris) against the third larval instars of L. sericata was evaluated, for the first time, through ingestion assays. The effect of sublethal concentrations on certain biological aspects, such as the pupation rates and adult emergence, was revealed. RESULTS The LC(50) values were 2.81, 4.60, 6.93, and 7.92% for fenugreek, celery, radish, and mustard, respectively. The adverse effects on larval treatment also included the survival of pupae and adults. The pupation rate was strongly decreased after treatment with 16% fenugreek and celery. Moreover, adult emergence was suppressed after treatment of larvae with 8% mustard, 12% radish, and 16% fenugreek and celery oils. The number of emerged males exceeded the number of females, which could lead to population decline. Morphologic abnormalities of larvae, pupae, and adults were recorded after treatment with all tested oils. CONCLUSION The results suggest that oils may represent new and safe potential insecticides for the control of blowflies.
Department of Preventive Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA. firstname.lastname@example.org
Myiasis is the infestation of living tissue by the larvae of flies in the order Diptera. Cutaneous involvement is the most common type of myiasis. Cutaneous myiasis can be subdivided into furuncular, migratory, and wound myiasis. Each subtype is reviewed with discussion of the larvae involved, presenting signs and symptoms, clinical differential diagnoses, and treatment. Preventive measures are also described. LEARNING OBJECTIVES: At the conclusion of this learning activity, participants should be familiar with the causal agents, clinical manifestations, and treatment of human cutaneous myiasis.
Other papers by authors:
Malar J. 2012 Aug 20;11 (1):281 22905743
Genetic polymorphisms associated with antimalarial antibody levels in a low and unstable malaria transmission area in southern Sri Lanka.
Rajika L Dewasurendra, Prapat Suriyaphol, Sumadhya D Fernando, Richard Carter, Kirk Rockett, Patrick Corran, Dominic Kwiatkowski, Nadira D Karunaweera
ABSTRACT: BACKGROUND: The incidence of malaria in Sri Lanka has significantly declined in recent years. Similar trends were seen in Kataragama, a known malaria endemic location within the southern province of the country, over the past five years. This is a descriptive study of anti-malarial antibody levels and selected host genetic mutations in residents of Kataragama, under low malaria transmission conditions. METHODS: Sera were collected from 1,011 individuals residing in Kataragama and anti-malarial antibodies and total IgE levels were measured by a standardized ELISA technique. Host DNA was extracted and used for genotyping of selected SNPs in known genes associated with malaria. The antibody levels were analysed in relation to the past history of malaria (during past 10 years), age, sex, the location of residence within Kataragama and selected host genetic markers. RESULTS: A significant increase in antibodies against Plasmodium falciparum antigens AMA1, MSP2, NANP and Plasmodium vivax antigen MSP1 in individuals with past history of malaria were observed when compared to those who did not. A marked increase of anti-MSP1(Pf) and anti-AMA1(Pv) was also evident in individuals between 45-59 years (when compared to other age groups). Allele frequencies for two SNPs in genes that code for IL-13 and TRIM-5 were found to be significantly different between those who have experienced one or more malaria attacks within past 10 years and those who did not. When antibody levels were classified into a low-high binary trait, significant associations were found with four SNPs for anti-AMA1(Pf); two SNPs for anti-MSP1(Pf); eight SNPs for anti-NANP(Pf); three SNPs for anti-AMA1(Pv); seven SNPs for anti-MSP1(Pv); and nine SNPs for total IgE. Eleven of these SNPs with significant associations with anti-malarial antibody levels were found to be non- synonymous. CONCLUSIONS: Evidence is suggestive of an age-acquired immunity in this study population in spite of low malaria transmission levels. Several SNPs were in linkage disequilibrium and had a significant association with elevated antibody levels, suggesting that these host genetic mutations might have an individual or collective effect on inducing or/and maintaining high anti-malarial antibody levels.
Distribution pattern of Plasmodium falciparum chloroquine transporter (pfcrt) gene haplotypes in Sri Lanka 1996-2006.
Jenny J Zhang, Tharanga N Senaratne, Rachel Daniels, Clarissa Valim, Michael Alifrangis, Priyanie Amerasinghe, Flemming Konradsen, Rupika Rajakaruna, Dyann F Wirth, Nadira D Karunaweera
Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, USA. email@example.com
Widespread antimalarial resistance has been a barrier to malaria elimination efforts in Sri Lanka. Analysis of genetic markers in historic parasites may uncover trends in the spread of resistance. We examined the frequency of Plasmodium falciparum chloroquine transporter (pfcrt; codons 72-76) haplotypes in Sri Lanka in 1996-1998 and 2004-2006 using a high-resolution melting assay. Among 59 samples from 1996 to 1998, we detected the SVMNT (86%), CVMNK (10%), and CVIET (2%) haplotypes, with a positive trend in SVMNT and a negative trend in CVMNK frequency (P = 0.004) over time. Among 24 samples from 2004 to 2006, we observed only the SVMNT haplotype. This finding indicates selection for the SVMNT haplotype over time and its possible fixation in the population.
Industrial Technology Institute, Colombo, Sri Lanka.
Antioxidant and antifungal activity were determined for the essential oil of Alpinia calcarata Roscoe (Zingiberaceae) rhizomes. Its antioxidant properties were investigated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay and thiobarbituric acid reactive substances (TBARS) assay. Butylated hydroxy toluene (BHT) and vitamin E served as positive controls. Antifungal activities were investigated against crop pathogens Curvularia spp. and Colletorichum spp. using the agar plate method. Fifty percent effective concentration (EC(50)) and % antioxidant index of the essential oil were 45 ± 0.4 and 16.1 ± 0.2 for DPPH and TBARS assays, respectively. The degree of, the essential oil's inhibition of the growth of crop pathogens Curvularia spp. and Colletorichum spp. varied with time period its effects were higher than greater than for the positive control, daconil. In conclusion, the essential oil of A. calcarata rhizomes possess moderate antioxidant property and promising antifungal activity.
Single-nucleotide polymorphism, linkage disequilibrium and geographic structure in the malaria parasite Plasmodium vivax: prospects for genome-wide association studies.
Pamela Orjuela-Sánchez, Nadira D Karunaweera, Mônica da Silva-Nunes, Natal S da Silva, Kézia K G Scopel, Raquel M Gonçalves, Chanaki Amaratunga, Juliana M Sá, Duong Socheat, Rick M Fairhust, Sharmini Gunawardena, Thuraisamy Thavakodirasah, Gawrie L N Galapaththy, Rabindra Abeysinghe, Fumihiko Kawamoto, Dyann F Wirth, Marcelo U Ferreira
Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, Brazil.
Geographic Structure of Plasmodium vivax: Microsatellite Analysis of Parasite Populations from Sri Lanka, Myanmar, and Ethiopia.
Sharmini Gunawardena, Nadira D Karunaweera, Marcelo U Ferreira, Myatt Phone-Kyaw, Richard J Pollack, Michael Alifrangis, Rupika S Rajakaruna, Flemming Konradsen, Priyanie H Amerasinghe, Mette L Schousboe, Gawrie N L Galappaththy, Rabindra R Abeyasinghe, Daniel L Hartl, Dyann F Wirth
Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts; Department of Parasitology, Faculty of Medicine, University of Colombo, Colombo, Sri Lanka; Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Parasitology Research Division, Department of Medical Research (Lower Myanmar), Myanmar; Centre for Medical Parasitology, Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark; Departments of Infectious Diseases and Clinical Microbiology, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark; Department of Zoology, University of Peradeniya, Peradeniya, Sri Lanka; International Water Management Institute, Delhi, India; Anti-Malaria Campaign, Ministry of Health, Colombo, Sri Lanka; Department of Organismic and Evolutionary Biology, Harvard University, Cambrige, Massachusetts.
Genetic diversity and population structure of Plasmodium vivax parasites can predict the origin and spread of novel variants within a population enabling population specific malaria control measures. We analyzed the genetic diversity and population structure of 425 P. vivax isolates from Sri Lanka, Myanmar, and Ethiopia using 12 trinucleotide and tetranucleotide microsatellite markers. All three parasite populations were highly polymorphic with 3-44 alleles per locus. Approximately 65% were multiple-clone infections. Mean genetic diversity (H(E)) was 0.7517 in Ethiopia, 0.8450 in Myanmar, and 0.8610 in Sri Lanka. Significant linkage disequilibrium was maintained. Population structure showed two clusters (Asian and African) according to geography and ancestry. Strong clustering of outbreak isolates from Sri Lanka and Ethiopia was observed. Predictive power of ancestry using two-thirds of the isolates as a model identified 78.2% of isolates accurately as being African or Asian. Microsatellite analysis is a useful tool for mapping short-term outbreaks of malaria and for predicting ancestry.
Department of Parasitology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo 08, Sri Lanka. firstname.lastname@example.org
Research involving leishmaniasis, a newly established disease in Sri Lanka, has focused mostly on parasitological and clinical factors, with inadequate understanding of other aspects, including its epidemiology and vector. The escalation in the spread of cutaneous leishmaniasis cases within Sri Lanka and the close resemblance (genotypic and phenotypic) between the local parasite Leishmania donovani MON-37 and the parasite causing visceral leishmaniasis in India (L. donovani MON-2), underscored by the more recent case reports of autochthonous cases of visceral and mucocutaneous-like disease, are clear warnings to the health authorities, scientists and policy makers. An effective control strategy is needed to contain further spread of cutaneous disease and avert a more-virulent form of leishmaniasis becoming endemic in Sri Lanka.
Nadira D Karunaweera, Marcelo U Ferreira, Anusha Munasinghe, John W Barnwell, William E Collins, Christopher L King, Fumihiko Kawamoto, Daniel L Hartl, Dyann F Wirth
Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115, USA.
The population structure of Plasmodium vivax remains elusive. The markers of choice for large-scale population genetic studies of eukaryotes, short tandem repeats known as microsatellites, have been recently reported to be less polymorphic in P. vivax. Here we investigate the microsatellite diversity and geographic structure in P. vivax, at both local and global levels, using 14 new markers consisting of tri- or tetranucleotide repeats. The local-level analysis, which involved 50 field isolates from Sri Lanka, revealed unexpectedly high diversity (average virtual heterozygosity [H(E)], 0.807) and significant multilocus linkage disequilibrium in this region of low malaria endemicity. Multiple-clone infections occurred in 60% of isolates sampled in 2005. The global-level analysis of field isolates or monkey-adapted strains identified 150 unique haplotypes among 164 parasites from four continents. Individual P. vivax isolates could not be unambiguously assigned to geographic populations. For example, we found relatively low divergence among parasites from Central America, Africa, Southeast Asia and Oceania, but substantial differentiation between parasites from the same continent (South Asia and Southeast Asia) or even from the same country (Brazil). Parasite relapses, which may extend the duration of P. vivax carriage in humans, are suggested to facilitate the spread of strains across continents, breaking down any pre-existing geographic structure.
H V Yamuna D Siriwardana, Harry A Noyes, Nicholas J Beeching, Michael L Chance, Nadira D Karunaweera, Paul A Bates
Liverpool School of Tropical Medicine, Liverpool, United Kingdom.
To investigate the relationship of cutaneous leishmaniasis isolates from Sri Lanka to known species, we performed DNA sequencing and microsatellite analyses. We identified Leishmania donovani as the agent of Sri Lanka cutaneous leishmaniasis and showed that these parasites are closely related to those causing visceral leishmaniasis in the Indian subcontinent.
Marcelo U Ferreira, Nadira D Karunaweera, Monica da Silva-Nunes, Natal S da Silva, Dyann F Wirth, Daniel L Hartl
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
Understanding the genetic structure of malaria parasites is essential to predict how fast some phenotypes of interest originate and spread in populations. In the present study, we used highly polymorphic microsatellite markers to analyze 74 Plasmodium vivax isolates, which we collected in cross-sectional and longitudinal surveys performed in an area of low malaria endemicity in Brazilian Amazonia, and to explore the transmission dynamics of genetically diverse haplotypes or strains. P. vivax populations are more diverse and more frequently comprise multiple-clone infections than do sympatric Plasmodium falciparum isolates, but these features paradoxically coexist with high levels of inbreeding, leading to significant multilocus linkage disequilibrium. Moreover, the high rates of microsatellite haplotype replacement that we found during 15 months of follow-up most likely do not result from strong diversifying selection. We conclude that the small-area genetic diversity in P. vivax populations under low-level transmission is not severely constrained by the low rates of effective meiotic recombination, with clear public health implications.
Sujith Prasad W Kumarasinghe, Suat Hoon Tan, Steven Thng, Thomas Paulraj Thamboo, Shen Liang, Yoke Sun Lee
National Skin Center, Singapore, Department of Pathology, Faculty of Medicine, National University of Singapore, Singapore. email@example.com
INTRODUCTION Progressive macular hypomelanosis (PMH), a condition of uncertain etiology, is characterized by asymptomatic hypopigmented macules predominantly located on the trunk. To date, there are no reports from South-East Asia concerning this condition. We sought to record the clinical features of PMH in Asian patients, identify etiologic factors, and study the structural and ultrastructural features of melanocytes in this disorder. METHODS Patients who presented to the National Skin Center with acquired, hypopigmented macules on the trunk, without a history of inflammation or infection, were recruited. Erythrocyte sedimentation rate (ESR), complete blood count, fasting blood glucose, liver function tests, skin scrapings for fungi, and skin biopsy specimens (from lesional and normal skin) were obtained. Biopsies were stained with hematoxylin and eosin (H&E), Fontana Masson, an immunohistochemical panel for identification of melanocyte differentiation antibodies (HMB 45, Melan A, and S100) and CD 68. Electron microscopy (EM) was also performed. The patients were evaluated every 3 months. RESULTS During a 9 month period, eight patients (all Chinese) presented with hypopigmented, ill-defined, confluent macules involving the lower aspect of the trunk. There were four men and four women, and the mean age was 25.9 years (range 19-45 years). Skin scrapings were negative for fungi and laboratory tests were normal. Microscopic evaluation of skin biopsy specimens showed reduced pigmentation of lesional as compared with normal appearing skin, but H&E-stained sections revealed only minimal histologic differences between lesional and normal skin. EM demonstrated a statistically significant (P = 0.047, Wilcoxon Signed Rank Test, Wilcoxon 95% CI 0.02-0.62) higher ratio of stage IV and late stage III (dark) melanosomes in normal vs. lesional skin. CONCLUSIONS PMH may occur among young adults in Singapore. Its etiology is uncertain. The melanin content of lesional skin appears to be less than that in normal sites. EM shows a higher ratio of immature melanosomes in lesional vs. normal skin.
Latest similar papers:
PLoS One. 2011 ;6 (12):e29521 22206019
A fly in the ointment: evaluation of traditional use of plants to repel and kill blowfly larvae in fermented fish.
Department of Systematic Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
In rural areas in Laos, fly larvae infestations are common in fermenting fish. Blowflies (Chrysomya megacephala, Diptera: Calliphoridae) are attracted to oviposit (and/or larviposit) onto fermenting fish which results in infestations with fly larvae. Knowledge of traditional use of plants to repel larvae during the production of fermented fish is common and widespread in Lao PDR. How effective are the most salient species in repelling, and killing fly larvae in fermenting fish? The three plant species most frequently reported to repel fly larvae during an ethnobotanical survey throughout Lao PDR were tested for repellence and larvicidal activity of fly larvae infesting fermented fish. The lethality and repellence of Tadehagi triquetrum (L.) H. Ohashi (Fabaceae), Uraria crinita (L.) Desv. ex DC.(Fabaceae) and Bambusa multiplex (Lour.) Raeusch. ex Schult.& Schult. f.(Poaceae) were tested in an experimental design using fermenting fish in Vientiane, Lao PDR. The repellent effect of fresh material of T. triquetrum and U. crinita, and the larvicidal effect of fresh B. multiplex, is significantly more effective than that of dried material of the same species, and the total effect (repellence and larvicidal effect combined) for each of the three species was significantly more effective for fresh than for dry material. Fresh material of T. triquetrum, U. crinita, or B. multiplex added on top of the fermenting fish repelled 50%, 54%, 37%, and killed 22%, 28%, and 40% of fly larvae. The total effect was not significantly different per species at 72%, 82%, and 77%, respectively. The three most salient species are effective in repelling and killing fly larvae in the production of fermented fish, and may be essential to augment food safety during traditional fermentation in open jars.
Comparison of tea and sesame seed oils as two natural antioxidants in a fish oil model system by radical scavenging activity.
Food Technology Department, College of Agriculture, Tarbiat Modares University, Tehran, Iran.
Tea and sesame seed oils, two natural antioxidants at 5% and 10% levels, were added to carp (Cyprinus caprio) and common kilka (Clupeonella cultiventris caspia) oils, and the peroxide value and thiobarbituric acid were evaluated after 13 days at 60 degrees C (oven test). The results showed that the antioxidant effects of tea and sesame seed oils in the two aforementioned fish oils were statistically similar. In addition, the radical scavenging activity (RSA) of tea and sesame seed oils (extracted with two solvents:n-hexane and benzene) and their methanolic extract (methanol-soluble phase), ethanolic extract (ethanol-soluble phase) and lipid fraction (non-soluble in methanol or ethanol) were evaluated by the 2,2-diphenyl-1-picrylhydrazyl radical method. The results revealed that the RSA of sesame seed oil was higher than that of tea seed oil (IC(50)= 52 mg and 45 mg, respectively). In addition, among ethanolic and methanolic extracts, the RSA of the ethanolic extract of sesame seed oil (IC(50)= 65 ml and 68 ml in n-hexane and benzene solvents, respectively) and of the ethanolic extract of tea seed oil in benzene solvent (IC(50)= 73 ml) were the highest. Also, the RSA in the lipid fraction, non-soluble phase of sesame seed oil was the highest (IC(50)= 74 mg and 81 mg in n-hexane and benzene solvents, respectively). Furthermore, after 6 days at 60 degrees C the RSA values of tea and sesame seed oils were the same.
Evaluation of sanitizing efficacy of acetic acid on Piper betle leaves and its effect on antioxidant properties.
Department of Biotechnology and Environmental Sciences, Thapar University, Patiala, Punjab, India.
The sanitizing efficacy of acetic acid and its effect on health beneficial properties of Piper betle leaves were determined. Betel leaves artificially inoculated with Aeromonas, Salmonella and Yersinia were subjected to organic acid (citric acid, acetic acid and lactic acid) treatment. Pathogen populations reduced by 4 log upon individual inoculation and up to 2 log in a mixed cocktail following treatment with 2% acetic acid during storage up to 20 h at 28 degrees C, indicating a residual antimicrobial effect on pathogen during storage. Antioxidant potential ethanolic extracts of both raw and treated P. betle leaves were assayed for free radical scavenging activities against 2,2-diphenyl-1-picryhydrazyl. Polyphenols, flavonoids and the reducing power of treated and untreated P. betle were also compared. No significant (P>0.05) changes were observed in antioxidant status; flavonoids, polyphenols and reducing power of treated betel leaves. Results indicate the feasibility of a simple intervention strategy for inactivating pathogens in edible leaves of P. betle.
Department of Biomedical Science, International Islamic University Malaysia, 25200 Kuantan Pahang Darul Makmur, Malaysia. firstname.lastname@example.org
This study was carried out to evaluate the antibacterial activity of aqueous and organic extracts of Thymus capitatus L.(Lamiaceae) leaves and stems. Dried ground powder leaves and stems were extracted with water (aqueous extracts), ethanol, dichloromethane and hexane (Soxhlet extracts). The antibacterial activity of these extracts was evaluated against bacteria using disc diffusion method. The result obtained showed that the leaves had stronger antibacterial activity than the stems extracts. The ethanolic extract had the highest yield products and the high antibacterial activity than all other solvents. The results suggest that essential oil as non-polar organic compounds could be the main active compounds in this plant. Therefore the antibacterial activity of leaves ethanol extracts (LEE) was compared with essential oils leaves extracts (LEO) of T. capitatus. The LEO showed greater antibacterial activity than LEE. The LEO showed a broad spectrum of antibacterial activity and the Pseudomonas aeruginosa was the most sensitive bacteria.
Antibacterial activities of crude extract of Aloe barbadensis to clinically isolated bacterial pathogens.
Department of Biotechnology, Institute of Allied Health (Paramedical) Services, Education and Training, Uttarakhand Forest Hospital Trust, Rampur Road, Haldwani, 263139, Uttarakhand, India.
The antibacterial activity of Aloe barbadensis was tested on clinically isolated bacterial pathogens i.e. Enterococcus bovis, Staphylococcus aureus, Escherichia coli, Proteus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa, Morganella morganii, and Klebsiella pneumoniae causing infection in human being. Ethanolic and aqueous extracts were used for the antibacterial effect, which was measured by the appearance of zone of inhibition. Relatively higher MIC concentrations were obtained for gram negative bacteria E. coli and K. pneumoniae, with ethanol extract; however, no inhibitory effect was noted for aqueous extract. Ethanolic extract possesses great inhibitory activity for gram positive bacteria, E. bovis followed by S. aureus. Among gram negative bacteria, highest inhibitory effect was observed with P. aeruginosa, followed by M. morganii, P. mirabilis, and P. vulgaris, which was significant (p < 0.01) than E. coli and K. pneumoniae. Antimicrobial activity tests of crude extract of A. barbadensis were carried out to validate the use of traditional medicinal herbal and results of this study tend to give credence to the common use of A. barbadensis gel and leaf.
[Larvicidal activity of Anacardium humile Saint Hill oil on Aedes aegypti (Linnaeus, 1762)(Diptera, Culicidae)]
Karla Rejane de Andrade Porto, Antonia Railda Roel, Márcia Marlene da Silva, Rosemary Matias Coelho, Eloty Justina Dias Scheleder, Alex Haroldo Jeller
Curso de Nutrição, Universidade Católica Dom Bosco, Campo Grande, MS, Brazil.
The objective of this study was to evaluate the potential of Anacardium humile (monkey nuts) against Aedes aegypti larvae. Hexane, ethanol and aqueous extracts and oil from leaves were obtained from plant material collected from the Brazilian savanna. These were tested at concentrations of 1%, 0.5%, 0.25%, 0.125%, 0.05% and 0.0125%, diluted in 1% dimethyl sulfoxide. The dead larvae were counted 24 hours later. The Probit analysis method was used to obtain the LC(50) and the respective confidence intervals. The conclusion was that only the oil extracted from Anacardium humile leaves caused 100% mortality among fourth-instar Aedes aegypti larvae, using concentrations of up to 0.125%. This seems to indicate that the active ingredients are present in the most apolar phase. This indicates that this plant has potential use as a larvicide against Aedes aegypti. However, new tests should be carried out using other plant organs, as well as using other methods and solvents for the extraction.
Mosquito larvicidal properties of various extract of leaves and fixed oil from the seeds of Caesalpinia bonduc (L) Roxb.
Department of Pharmacognosy, Madurai Medical College, Madurai-20, Tamil Nadu, India.
A Preliminary laboratory trial was undertaken to determine the efficacies of petroleum ether, ethanolic, aqueous extracts of dried leaves and fixed oil from the seeds of Caesalpinia bonduc (L). Roxb (Family: Caesalpiniaceae) at various concentrations against the fourth instar larvae of Culex quinquefasciatus by following the WHO guidelines. Hundred per cent mortality was observed in 1% concentration of petroleum ether and ethanolic extract of leaf, whereas it was 55% in 2.5% concentration of aqueous extract and 92.6% in 2.5% concentration of fixed oil. The active constituent responsible for the mortality is to be isolated to come up with a promising larvicidal agent, which will be economic, non pollutant and ecofriendly.
Med Princ Pract. 2007 ;16 (1):47-52 17159364
Department of Pharmacognosy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand.
OBJECTIVE To develop a TLC-densitometric method for the determination of barakol content in Senna siamea leaf and flower extracts, and to compare the barakol content in mature leaves, young leaves and young flowers of the plant which are consumed as a vegetable in curry. MATERIALS AND METHODS The extraction of pure barakol was performed by boiling the fresh young leaves of S. siamea with 0.5% sulfuric acid followed by chloroform extraction. The extract was further purified and recrystallized from absolute ethanol. Authentic sample of barakol was used for the validation of the TLC-densitometric method. Chromatography was performed on a TLC aluminium plate precoated with silica gel 60 F(254)as a stationary phase and chloroform-methanol (85:15 v/v) as a solvent system. Fifteen percent ethanolic extracts of mature leaves, young leaves and flowers of S. siamea were analyzed and compared for barakol content using the validated TLC-densitometric method. Both the validation and analysis of barakol by TLC-densitometry were carried out at the absorbance mode of 366 nm. RESULTS Barakol was extracted as pure lemon-yellow crystals from young S. siamea leaves with 0.1% yield. Linearity was found over the range of 200-900 ng/spot (r(2)= 0.997). The developed method gave high precision (%RSD < 0.50) and accuracy (average 101.12%). The limit of detection and limit of quantitation were 8 and 50 ng, respectively. Barakol content in young leaves, mature leaves and young flowers were 1.67, 0.78 and 1.43% dry weight, respectively. R(f) value of the barakol in young leaves, young flowers and authentic sample was the same: 0.45 +/- 0.03. CONCLUSION The TLC-densitometric method was simple, precise and convenient; hence it is an effective procedure for the simultaneous determination of barakol in plant extracts.
Larvicidal activity of extracts of Ginkgo biloba exocarp for three different strains of Culex pipiens pallens.
Department of Parasitology, Nanjing Medical University, Jiangsu Province Key Lab of Modern Pathogen Biology, Nanjing 210029, People's Republic of China.
Ethanolic extracts from the Ginkgo biloba L. exocarp from the Chinese ginkgo were assayed against larvae of three strains of Culex pipiens pallens Coquillett. The chemical compositions were detected using a Hewlett-Packard 6890/5973 mass spectrometric detector. The larvicidal bioassay was carried out according to the recommendations of the World Health Organization. The analysis of the essential oil of ginkgo exocarp showed that its major components are ginkgo acid (85.3%) and ginkgo phenolic (5.69%). The larvicidal bioassay showed that extracts of ginkgo exocarp have LC50 of 18.6, 12.7, and 25.0 mg/liter for deltamethrin-susceptible, deltamethrin-resistant, and field strains, respectively. The acute toxicity concentrations of the ginkgo extracts that killed 50%(LD50) of Wistar rats within 2 wk and young carp within 96 h were 4947.2 mg/kg and 557.9 mg/liter, respectively. These results are promising in creating new, effective, and affordable approaches to mosquito control.
S F Mbatchi, B Mbatchi, J T Banzouzi, T Bansimba, G F Nsonde Ntandou, J-M Ouamba, A Berry, F Benoit-Vical
Centre d’Etude et de Recherche Médecins d’Afrique (CERMA), B.P. 45, Brazzaville, Congo; Service de Parasitologie et Mycologie, Hôpital de Rangueil, CHU Toulouse, 1 Avenue Jean Poulhes, TSA 50032, 31059 Toulouse Cedex 9, France.
Sixty-six extracts of 18 plants commonly used by traditional healers in Congo Brazzaville for the treatment of malaria have been investigated for in vitro antiplasmodial activity. Ethanolic and dichloromethane extracts of 7 among the 18 studied plants were moderately active (10mug/ml<IC(50)<50mug/ml). These extracts concerned Cassia siamea (bark), Cogniauxia podolaena (root), Landolphia lanceolata (root and leaves), Millettia versicolor (leaves), Pseudospondias microcarpa (leaves), Uapaca paludosa (leaves) and Vernonia brazzavillensis (leaves). These results support their traditional use as antimalarial plants. The bark extract of Uapaca paludosa showed a good activity (<10mug/ml) and the extracts from Quassia africana (root and leaves) even exhibited IC(50) values less than 1mug/ml. Except for Quassia africana, for which the three solvents (water, ethanol and dichloromethane) present an effective extraction, no aqueous extract was highly active. The cytotoxicity of aqueous, DCM and ethanol extracts of Quassia africana was tested on KB cell lines.