Antibacterial activity of plant extracts from northwestern Argentina

Isolation and characterization of Streptococcus agalactiae inducing mass mortalities in cultured Nile tilapia (Oreochromis niloticus) with trials for disease control using zinc oxide nanoparticles and ethanolic leaf extracts of some medicinal plants

BACKGROUND

Streptococcus agalactiae (Group B streptococcus, GBS) induces a serious infection that can harm not only aquatic life but also humans and other animals. In a fish farm in southern Egypt, Nile tilapia (Oreochromis niloticus) has developed an epidemic with clinical symptoms resembling piscine streptococcosis.

RESULTS

Initial microscopic inspection of the affected fish brain and kidney indicated the presence of Gram-positive cocci. S. agalactiae was effectively isolated and identified using nucleotide homology of the 16S rRNA and species-specific PCR. The partial 16S rRNA sequence was deposited in the GenBank database at the NCBI and given the accession number MW599202. Genotyping using RAPD analysis indicated that the isolates in the present study belonged to the same genotypes and had the same origin. The challenge test, via immersion (9.2 × 107, 9.2 × 106, and 9.2 × 105 CFU/ml for 1 h) or intraperitoneal injection (4.6 × 107, 4.6 × 106, and 4.6 × 105 CFU/fish), elicited clinical symptoms resembling those of naturally infected fish with a mortality rate as high as 80%. The ability to create a biofilm as one of the pathogen virulence factors was verified. Zinc oxide nanoparticles and the ethanolic leaf extracts of nine medicinal plants demonstrated considerable antibacterial activities against the tested S. agalactiae strain with low minimum bactericidal concentrations (MBC) and minimum inhibitory concentrations (MIC). The ethanolic leaf extracts from Lantana camara and Aberia caffra showed potent antibacterial activity with MBC values of 0.24 and 0.485 mg/ml, and MIC values of 0.12 & 0.24 mg/ml, respectively.

CONCLUSION

This study isolated S. agalactiae from O. niloticus mortalities in a fish farm in Assiut, Egypt. The pathogen persists in fish environments and can escape through biofilm formation, suggesting it cannot be easily eliminated. However, promising findings were obtained with in vitro control employing zinc oxide nanoparticles and medicinal plant extracts. Nevertheless further in vivo research is needed.

Analysis of Antibiofilm Activities of Bioactive Compounds from Honeyweed (Leonurus sibiricus) Against P. aeruginosa: an In Vitro and In Silico Approach

Leonurus sibiricus (Red verticilla, honeyweed) is a type of herbaceous plant predominantly found in Asian subcontinents as weed in crop fields and is widely used for treating diabetes, bronchitis, and menstrual irregularities. However, there is a dearth of study in the application of the plant phytocompounds for treating biofilm-associated chronic infections. The bioactive compounds mainly comprise of tri-terpenes, di-terpenes, phenolic acid, and flavonoids which may have potential role as antimicrobial and antibiofilm agents. Acute and chronic infection causing microbes usually form biofilm and develop virulence factors and antibiotic resistance through quorum sensing (QS). In this study, the bioactive compounds leosibirin, sibiricinone A, leosibirone A, leonotin, quercetin, lavandulifolioside, and myricetin were identified using GC-MS analysis. These were used for analyzing the antibiofilm and anti-quorum sensing activities (rhamnolipid, AHL assay, swarming motility assay) against the biofilm formed by Pseudomonas aeruginosa, the most significant nosocomial disease-causing bacteria. The compounds were able to bring about maximum inhibition in biofilm formation and QS. Although the antibiofilm activity of the phytoextract was found to be higher than that of individual phytocompounds at a concentration of 250 µg/mL, quercetin and myricetin showed highest antibiofilm activity against Pseudomonas aeruginosa, respectively, at MIC values of 135 µg/mL and 150 µg/mL against P aeruginosa. FT-IR study also revealed that the active ingredients were able to bring about the destruction of exopolysaccharides (EPS). These observations were further validated by molecular docking interactions that showed the active ingredients inhibit the functioning of QS sensing proteins by binding with them. It was observed that myricetin showed better interactions with the QS proteins of P. aeruginosa. Myricetin and quercetin show considerable inhibition of biofilm in comparison to the phytocompounds. Thus, the present study suggests that the active compounds from L. sibiricus can be used as an alternate strategy in inhibiting the biofilm formed by pathogenic organisms.

Selective extraction of antimicrobial agents from Jodina rhombifolia by supercritical fluid carbon dioxide: phytochemical profile

The goals of this study were to determine the phytochemical profile of Jodina rhombifolia and to evaluate the ability of supercritical fluids (ScFCO₂) to selectively extract the metabolites responsible for the bioactivity. This species has simple aromatic compounds and lignan monomers, as well as glycerides containing epoxidized saturated fatty acids. Regarding the extraction by ScFCO₂, the extracts showed a higher antimicrobial activity against human pathogenic strains, with respect to the ethanolic extracts obtained from plant residues after extraction by ScFCO₂. Furthermore, the bioactive compounds were concentrated in just 1% P/P of the weight of the dry plant material. Extraction by ScFCO₂ was carried out under different conditions of pressure and temperature, with the best results being obtained at 30 °C and 30 MPa. The results obtained demonstrate the advantages of ScFCO₂ extractions over classical solvent extractions, in terms of improved safety and the ability to selectively extract the compounds of interest.

A new antiprotozoal compound from Calendula officinalis

A new phytoconstituent; (6Z,9Z)-heptadeca-6,9-diene-5,11-dione (1) was isolated from Calendula officinalis methanol extract. The structure of 1 was determined based on the analysis of NMR spectra and HRESIMS. It was tested for antimicrobial and antiprotozoal activities. Compound 1 showed leishmanicidal activity against L. donovani amastigote with an IC₅₀ of 16.4394 µM and IC₉₀ of 28.9015 µM and a weak antitrypanosomal activity with an IC₅₀ of 37.6136 µM. The cytotoxicity of 1 was evaluated using standard experimental procedures against THP1 cells and no cytotoxicity was observed indicating its selectivity and safety.Supplemental data for this article can be accessed here.

Enhancing recovery of bioactive compounds from Cosmos caudatus leaves via ultrasonic extraction

Cosmos caudatus (C. caudatus) is a medicinal plant that is high in bioactive compounds such as phenolics. In this study, an ultrasound extraction method was used to optimise the extraction of bioactive compounds from C. caudatus leaves. Response surface methodology (RSM) based on a Box-Behnken design (BBD) was applied to obtain the optimum extraction parameters which is solid–liquid ratio (10–30 g/mL), particle size (180–850 µm) and extraction time (20–30 min) for maximal quercitrin and total phenolic content (TPC) yields. Analysis of antimicrobial activity was performed against two human pathogenic microbes: Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) by the agar well diffusion method. The optimal ultrasonic extraction condition was as follow: solvent-liquid ratio of 1:28 (g/mL), particle size of 485 µm, and duration of 30 min, respectively. Remarkably, extraction using ultrasonic method had recovered more bioactive content and antioxidant activity than the Soxhlet method. The extract also exhibited good antimicrobial activities. Due to the above findings, the ultrasonic extraction was found to be suitable to improve recovery extraction of quercitrin and TPC from C. caudatus leaves. It also opens the possibility that the plant extract can be used for functional food and antimicrobial agents in various applications.

Phytoconstituents screening and antimicrobial activity of the invasive species Nicotiana glauca collected from Al-Baha region of Saudi Arabia

Nicotiana glauca belonging to the family Solanaceae is an exotic perinnial bushy species that recently has invaded the mountainous areas of Al-Baha region at the south-west of Saudi Arabia, causing degredation to soil and vegetation composition of those mountains. Accordingly, this plant must be either removed or exploited as a source of useful products such as medicines as it has been proven to contain many effective compounds with therapeutic properties. Thus, the current study aimd to screening N. glauca preliminary phytoconsitiuents and its anticmicrobial activity. Results showed that varying amounts of alkaloids, steroid, tannins, flavonoid, were present in the extracts of N. glauca leaves, stems and flowers. Saponins were present only in the flowers extract. However, all previuos bioactive compounds were absent in the roots except alkaloids, therefore, roots posses lesser amount of the phytoconstituents compared to the other parts of the plants. Leaves extracts inhibited the growth of E. coli (16.3 ± 0.71 mm) and also inhibited the growth of S. aureus (11.0 ± 0.23 mm), while, the flower extracts also inhibited the growth of E. coli (6.7 ± 0.65 mm), and also inhibited the growth of S. aureus (15.8 ± 0.52 mm). This result coincide with the previous results of the screening of N, glauca phytochemicals where the highest amounts found in leaves and flowers extracts. The inhibition zone of the antibiotic gentamycin (reference control) were 32 mm in S. aureus and 38 mm in E. coli. The inhibition zone of gentamycin (reference control) were 32 mm in S. aureus and 38 mm in E. coli. The minimum inhibitory concentration (MIC) of ethyl acetate was ranged (1.5–2 mg/ml). The lower MIC is an indication of high effectiveness of extract. Therefore, such bioactive property would support the idea that removing N. glauca from the mountainous areas of Al-Baha, Saudi Arabia, is not the only solution, but the plant can be exploited as a beneficial source of medicinal and economic purposes such as; antibacterial, antifungal and insecticidal, however, further comprehensive exploration is recommended to confirm such propreties.

Impact of the invasive plant species "Nicotiana glauca" toxins on the larvae of the invasive insect species "Rhynchophorus ferrugineus": A damaging pest of date palm trees in Saudi Arabia

The wild tree tobacco (Nicotiana glauca) is an alien species that invaded vast areas of the Southwestern region of Saudi Arabia. While, the Red Palm Weevil (RPW) (Rhynchophorus ferrugineus) is considered to be the most damaging invasive insect species of palm trees all over the kingdom of Saudi Arabia, causing major economic losses to farmers and the economy of the country. Using conventional insecticides to control harmful insects such as RPW has undesirable effects on the environment and human health. Alternatively, using biocontrol agents such as poisonous extracts from N. glauca might be a better approach in pest management and can be considered as an eco-friendly, cost-effective, and safe alternative. Therefore, the current study aimed to evaluate the larvicidal effect of N. glauca aqueous extracts against the red palm weevil larvae. The plant specimens were collected from Al-Baha region in the Southwest of Saudi Arabia. Each single test consisted of 20 larvae, and N. glauca preparations were; 1, 1.5, 2, 2.5, and 3 ml, besides the control test. Results obtained for the effect of botanical extracts; leaf, flower, stem and root against R. ferrugineus larvae for an exposure period of 24 hr. at the concentrations of 2.8, 4.2, 6.0, 7.0 and 8.0 ppm. The concentrations for N. glauca extracts reflected an LC₅₀ of 2.7 ppm for leave, 2.6 ppm for flower, 2.8 ppm for stem and 7.00 ppm for root. While, the same concentrations extracts reflected an LC₉₅of 11 ppm for leaf, 9.6 ppm for flower, 8.9 ppm for stem and 13.00 ppm for root. These results showed that N. glauca extracts have a remarkable potentiality as insecticidal substances that can be used as an ecofriendly integrated approach for the management of R. ferrugineus.

Sophorolipid Biosurfactant Can Control Cutaneous Dermatophytosis Caused by Trichophyton mentagrophytes

Trichophyton mentagrophytes, a zoophilic species, is one of the most frequently isolated dermatophytes in many parts of the world. This study investigated the efficacy of a sophorolipid (SL-YS3) produced by Rhodotorula babjevae YS3 against dermatophytosis caused by T. mentagrophytes. SL-YS3 was characterized by gas chromatography–mass spectrometry (GC–MS) and ultra-performance liquid chromatography, coupled with electrospray mass spectrometry (UPLC-ESI-MS). SL-YS3 comprised of six different fatty acids as the hydrophobic components of constituent congeners and sophorose as the hydrophilic component. Inhibitory effects of purified SL-YS3 against hyphal growth was found to be 85% at a 2 mg ml^–1 concentration, and MIC was 1 mg ml^–1. Microscopic examination with scanning electron microscopy (SEM), atomic force microscopy, and confocal laser scanning microscopy (CLSM) revealed that SL-YS3 exerts its effect by disrupting cell membrane integrity causing cell death. SL-YS3 was also effective in reducing the biofilms formed by T. mentagrophytes, which was observed spectrophotometrically with crystal-violet staining and further validated with SEM and CLSM studies of treated biofilms. In vivo studies in a mouse model of cutaneous dermatophytosis involving macroscopic observations, percent culture recovery from skin samples, and histopathological studies showed that SL-YS3 could effectively cure the infected mice after 21 days of topical treatment. Terbinafine (TRB) was used as a standard drug in the experiments. We demonstrate, for the first time, the antidermatophytic activity of a sophorolipid biosurfactant. The findings are suggestive that SL-YS3 can be formulated as a novel antifungal compound to treat cutaneous mycoses caused by T. mentagrophytes.

Antibacterial activity of Syzygium aromaticum (clove) against uropathogens producing ESBL, MBL, and AmpC beta-lactamase: Are we close to getting a new antibacterial agent?

Introduction

The present study was done to access the antibacterial activity of clove (Syzygium aromaticum) against extended-spectrum beta-lactamase (ESBL), metallo-beta-lactamase (MBL), and AmpC beta-lactamase-producing gram-negative bacteria causing urinary tract infection.

Methods

A total of 221 gram-negative uropathogens were isolated and screened for beta-lactamase (ESBL, MBL, and AmpC) production and further tested against ethanolic extract of clove (S. aromaticum) for its antibacterial activity.

Results

Clove was effective against all gram-negative isolates but the best antibacterial activity was shown against Proteus species with 19 mm zone of inhibition, 0.39 mg/ml minimum inhibitory concentration (MIC) and 0.19 mg/ml minimum bactericidal concentration (MBC).

Conclusions

Clove extract showed different antibacterial potential against all gram-negative uropathogens. Clove activity for particular strain was found to be similar between isolates producing beta-lactamase and non beta-lactamase.

Methanol soluble fraction of fruits of Annona muricata possesses significant antidiarrheal activities

Medicinal plants are the major sources of traditional treatment of disease in Indian subcontinent due to abundant presence of plants and vast side effects of synthetic drug. The present study was subjected to observe in vitro thrombolytic, antibacterial, and in vivo antidiarrheal activities of methanol soluble fraction of fruits of Annona muricata. In thrombolytic activity assay, various concentrations (2 ─ 10 mg/ml) of methanol soluble fraction was used and dose dependently less potent activity was found. The maximum clot lysis 18.33% (p* < 0.05) was achieved at 10 mg/ml of methanolic fruit extract, whereas standard drug streptokinase showed 55.50% (p*** < 0.001) clot lysis. In antibacterial assay, disc diffusion method was used comprising two gram positive (S. aureus and Micrococcus luteus) and two gram negative (E. coli and P. aeruginosa) bacteria. None of four (0.25, 0.5, 1, and 5 mg/disc) concentration of fruit extract showed antibacterial potentiality, whereas standard amikacin (3 mg/disc) revealed strong antibacterial activities (=~ 23 ─ 24 mm of MIC). To evaluate antidiarrheal activity, castor oil induced diarrhea was created in Swiss albino mice and different doses (100, 200, and 400 mg/kgbw) of fruit extract was introduced post orally. All of three different doses of fruit extract showed significant (p < 0.05 ─ 0.001) antidiarrheal activities. Notably, the percent inhibition of diarrhea by methanolic extract of fruits of Annona muricata was found to be 58.38% at a dose of 400 mg/kgbw. The effect of vehicle saline (10 ml/kgbw) was considered as control and loperamide (5 mg/kgbw) as standard that provided 67.01% inhibition of diarrhea. The results suggest that, the fruits of Annona muricata possess potent antidiarrheal properties, providing scientific basis of using the plant parts in the treatment of diarrheal disease.

Plant odors trigger clearing behavior in foraging trails- do they represent olfactory obstacles?

Foraging trails of leaf-cutting ants may be exposed to plant material that interferes with foragers' flux either by physically blocking it or due to secondary metabolites which affect insect behavior. We hypothesized that plant secondary metabolites such as plant volatiles may interfere with pheromone communication, triggering clearing behavior. We impregnated small pieces of paper with different plant odors from native and exotic species and placed them in the middle of foraging trails of the leaf-cutting ant Acromyrmex lobicornis. As a control, we used papers impregnated with trail odor. The paper used as substrate for the odors did not constitute a physical obstacle based on its small surface area. Papers treated with trail odor did not interfere with ant flux and were not removed from the trail. However, when papers were treated with plant odors, they were removed from the trail in most of the cases and ant flux was reduced significantly by 15-28%. We found that ants tapped the tip of their gaster against the ground around the treated papers only when they were impregnated with foreign odors. The number of gaster tappings as well as the time between the placement of the paper and its removal increased with plant odor concentration. However, the decision to remove the paper was not correlated with the number of gaster tappings. Interestingly, clearer ants were smaller than forager ants, suggesting there is morphological differentiation in clearing behavior of the trail. Results from the current study also suggest that odors trigger clearing behavior on foraging trails and affect trail marking behavior. Our results provide information about the potential for plant compounds to constitute obstacles, even when they do not physically obstruct the trail. We conclude that odors may trigger clearing behavior by interfering with pheromone communication.

A comparative study of phytoconstituents and antibacterial activity of in vitro derived materials of four Passiflora species

Passiflora species are well known for their common use in popular medicine for the treatment of several diseases, such as insomnia, anxiety, and hysteria, in addition to their anti-inflammatory, antioxidant, analgesic and antibacterial potential. However, few data about the chemical composition and the medicinal potential of in vitro derived materials are available. Therefore, the goal of this work was to compare, for the first time, the phytoconstituents of in vitro derived materials of four Passiflora species, and evaluate the antibacterial potential of their extracts against 20 Gram-positive and negative strains. Chromatographic analysis indicated the presence of saponins in roots extracts from all studied species, whereas leaf extracts presented both saponins and flavonoids. Extracts from leaves and roots of P. alata and P. foetida exhibited a selective inhibitory activity against B. thuringiensis and S. pyogenes, which might be related to the presence of a high concentration of secondary metabolites, including flavonoids and saponins.

Microbiological Assessment of Moringa Oleifera Extracts and Its Incorporation in Novel Dental Remedies against Some Oral Pathogens

AIM:

To assess the antibacterial and antifungal potentials of different parts of Moringa oleifera plant using different extraction methods in attempts to formulate natural dental remedies from this plant.

MATERIAL AND METHODS:

Three solvents extracts (Ethanol, acetone, and ethyl acetate) of different parts of Egyptian Moringa tree were prepared and tested against oral pathogens: Staphylococcus aureus, Streptococcus mutans, and Candida albicans using disc diffusion method; As well as to incorporate the plant extract to formulate experimental toothpaste and mouthwash. The two dental remedies were assessed against the same microbial strains. Statistical analysis was performed using One-Way ANOVA test to compare the inhibition zone diameter and t-test.

RESULTS:

Ethanol extracts as well as leaves extracts demonstrated the highest significant mean inhibition zone values (P ≤ 0.05) against Staphylococcus aureus and Streptococcus mutans growth. However, all extracts revealed no inhibition zone against Candida albicans. For dental remedies, experimental toothpaste exhibited higher mean inhibition than the mouthwash against Staphylococcus aureus, Streptococcus mutans and only the toothpaste revealed antifungal effect against Candida albicans.

CONCLUSION:

The different extracts of different parts of Moringa showed an antibacterial effect against Staphylococcus aureus and Streptococcus mutans growth. The novel toothpaste of ethanolic leaves extract has antimicrobial and antifungal potential effects all selected strains.

Antioxidant, antidiarrheal, hypoglycemic and thrombolytic activities of organic and aqueous extracts of Hopea odorata leaves and in silico PASS prediction of its isolated compounds

Background

Hopea Odorata, locally known as Telsur (Bangladesh), has some traditional uses as folk medicine. This study aims to investigate the antioxidant, antidiarrheal, hypoglycemic and thrombolytic activities of H. odorata leaf extracts as new therapeutic prospects predicting the activity of some of the isolated compounds of this plant.

Methods

Leaves of Hopea odorata was extracted with pure methanol (MEHO), ethanol (EEHO) and water (AEHO). The extract was tested for antioxidant activity by using reducing power and H₂O₂ scavenging assay. Antidiarrheal effects were assayed by three standard methods of bioassay: Castor oil-induced diarrhea, Castor oil induced enteropooling and gastrointestinal transit test. Hypoglycemic effect was determined by normoglycemic model of mice. Thrombolytic activity was evaluated by clot lyses test for human and mice blood. In silico PASS prediction was applied for phytoconstituents namely Balanocarpol, Hopeaphenol and Ampelopsin H isolated from this plant.

Result

Among the all extracts, MEHO exhibited strong antioxidant activity in both reducing power and H₂O₂ scavenging assay. Phenol content of MEHO was 297.22 ± 0.78 mg/g and flavonol content was 91.53 ± 1.82 mg/g. All the experiment of extracts at dose of 200 and 400 mg/kg and the standard drug loperamide (5 mg/kg) showed significant (p < 0.001) inhibition against castor oil induced diarrhea and castor oil induced enteropooling in mice. There were also significant (p < 0.01) reduction in gastrointestinal motility in the charcoal meal test. Leaf extract showed no significant (P < 0.01) decrease of blood glucose compared to Glibenclamide in normoglycemic mice. Using an in vitro thrombolytic model, MEHO showed the highest and significant clot lysis of human and mice blood compared to Streptokinase. PASS predicted the wide range of antioxidant, free radical scavenger, Nitric oxide scavenger, cardioprotectant, hepatoprotectant, thrombolytic, fibrinolytic, antibacterial, antifungal, anticarcinogenic, anthelmintic and anti-inflammatory activity of examined phytoconstituents.

Conclusion

These findings suggest that the plant may be a potential source of new antidiarrheal, thrombolytic and antioxidative agents but it is found to have no antidiabetic capability. PASS prediction matched with present study for the extracts. Further study needs to identify the PASS predicted biological actions of the phytoconstituents.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1461-x) contains supplementary material, which is available to authorized users.

Wound Healing Activity of a Traditionally Used Poly Herbal Product in a Burn Wound Model in Rats

BACKGROUND

Burns are known as one of the most common and destructive forms of injury with a vast spectrum of consequences. Despite the discovery of various antibacterial and antiseptic agents, burn wound healing still has remained a challenge to modern medicine. Plants, with a valuable traditional support, have been considered as potential agents for prevention and treatment of disorders in recent years. However, modern scientific methods should be applied to validate the claims about the therapeutic effects of the herbal products.

OBJECTIVES

This study was conducted to evaluate the wound-healing activity of a poly herbal cream (PHC), retrieved from Iranian Traditional Medicine (ITM), in a rat burn wound model in Iran.

MATERIALS AND METHODS

In this experimental study, PHC containing aqueous extracts of Malva sylvestris and Solanum nigrum leaves and oily extract of Rosa damascena petals was used. Second-degree burn wounds were induced in four groups of five rats each. Group 1 received no treatment while groups 2, 3 and 4 were given cream base, silver sulfadiazine (SS) 1% and PHC, respectively to compare the efficacy of PHC with the negative and positive control groups. The percentage of wound healing on days 2, 6, 10 and 14 and histopathological parameters of healed wounds on the 14th day were assessed. Antioxidant and antimicrobial activities of PHC were evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and micro-dilution methods, respectively.

RESULTS

There was a significant improvement in healing percentage of PHC-treated rats in comparison to the other groups at the end of the treatment period (87.0% ± 2.1% for PHC in comparison to 32.2% ± 1.6%, 57.0% ± 5.3% and 70.8% ± 3.5% for the control, cream base and SS groups, respectively). Moreover, the healed wounds in PHC-treated animals contained less inflammatory cells and had desirable re-epithelialization with remarkable neovascularization. In addition to the antioxidant activity, PHC exhibited antibacterial effect against Staphylococcus aureus.

CONCLUSIONS

Poly herbal cream experimentally and histopathologically revealed a burn wound healing activity probably due to the antioxidant, anti-inflammatory and antimicrobial activities of its phytochemical contents. Therefore, this study confirms the use of M. sylvestris, S. nigrum and R. damascena in burn prescriptions in ITM.

Antifungal activity of 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone against Candida albicans: evidence for the antifungal mode of action

The main secondary metabolite of Senecio nutans is 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone (4HMBA). The antifungal activity of this compound and three derivatives was assessed using Candida albicans. 4HMBA exhibited the highest antifungal activity among the assayed compounds. The Fractional Inhibitory Concentration (FIC = 0.133) indicated a synergistic fungicidal effect of 4HMBA (5 mg L(-1)) and fluconazole (FLU) (0.5 mg L(-1)) against the C. albicans reference strain (ATCC 10231). Microscopy showed that 4HMBA inhibits filamentation and reduces cell wall thickness. Our findings suggest that 4HMBA is an interesting compound to diminish resistance to commercial fungistatic drugs such as fluconazole.

Antimicrobial activity of Anonna mucosa (Jacq.) grown in vivo and obtained by in vitroculture

Brazilian flora includes numerous species of medicinal importance that can be used to develop new drugs. Plant tissue culture offers strategies for conservation and use of these species allowing continuous production of plants and bioactive substances. Annona mucosa has produced substances such as acetogenins and alkaloids that exhibit antimicrobial activities. The widespread use of antibiotics has led to an increase in multidrug-resistant bacteria, which represents a serious risk of infection. In view of this problem, the aim of this work was to evaluate the antibacterial potential of extracts of A. mucosa obtained by in vitro techniques and also cultured under in vivo conditions. Segments from seedlings were inoculated onto different culture media containing the auxin picloram and the cytokinin kinetin at different concentrations. The calluses obtained were used to produce cell suspension cultures. The materials were subjected to methanol extraction and subsequent fractionation in hexane and dichloromethane. The antimicrobial activity against 20 strains of clinical relevance was evaluated by the macrodilution method at minimum inhibitory and minimum bactericidal concentrations. The extracts showed selective antimicrobial activity, inhibiting the growth of Streptococcus pyogenes and Bacillus thuringiensis at different concentrations. The plant tissue culture methods produced plant materials with antibacterial properties, as well as in vivo grown plants. The antibacterial activity of material obtained through biotechnological procedures of A. mucosa is reported here for the first time.

Ultraviolet-B radiation effects on phenolic profile and flavonoid content of Kalanchoe pinnata

Ultraviolet-B radiation is an important abiotic factor that can stimulate the production of secondary metabolites, including polyphenolic compounds. Kalanchoe pinnata (Crassulaceae) is a medicinal plant popularly used in Brazil for treating wounds and inflammation. This species is rich in phenolic compounds, which could account for some of its biological activities, including antileishmanial, antihypertensive and antibacterial properties. We investigated the effects of supplemental UV-B radiation on the phenolic profile, antioxidant activity and total flavonoid content of leaves of K. pinnata. Plants were grown under white light (W - control) and supplemental UV-B radiation (W+UVB). Supplemental UV-B radiation enhanced the total flavonoid content of the leaf extracts, without affecting the antioxidant activity or yield of extracts. Analysis by TLC and HPLC of W and W+UVB leaf extracts revealed quantitative and qualitative differences in their phenolic profiles. W+UVB extracts contained a higher diversity of phenolic compounds and a larger amount of quercitrin, an important bioactive flavonoid of this species. This is the first report of the use of ImageJ® program to analyze a TLC visualized by spraying with NP-PEG reagent. UV-B radiation is proposed as a supplemental light source in K. pinnata cultivation in order to improve its flavonoid composition.

Quercetin induces endoplasmic reticulum stress to enhance cDDP cytotoxicity in ovarian cancer: involvement of STAT3 signaling

There is an urgent need to make cisplatin (cDDP) more effective and less toxic in the treatment of ovarian cancer for its systemic side effects and high resistance rate. In this study, we investigated the effect of quercetin (Qu) pretreatment on the potentiation of cDDP in ovarian cancer. We found that Qu pretreatment significantly enhanced cDDP cytotoxicity in an ovarian cancer cell line and primary cancer cells. In addition, we demonstrated that Qu elicited obvious endoplasmic reticulum stress (ERS) and activated all three branches of ERS in ovarian cancer. Specific inhibitors of each ERS pathway, as well as the general ERS stabilizer tauroursodeoxycholic acid, notably diminished such enhancing effects. Furthermore, Qu notably suppressed STAT3 phosphorylation, leading to downregulation of the BCL-2 gene downstream of STAT3. Moreover, blocking ERS restored the protein levels of phosphorylated STAT3 as well as BCL-2 expression, thus abolishing the chemosensitization potency of Qu; these results revealed that Qu affected the STAT3 pathway to enhance cDDP cytotoxicity, and this effect involved ERS signaling. In a xenograft mouse model of ovarian cancer, Qu enhanced the antitumor effect of cDDP. Tumors from mice treated with cDDP in combination with Qu pretreatment had repressed STAT3 phosphorylation, lower BCL-2 and higher apoptosis levels compared with those from the other groups. Meanwhile, Qu markedly reduced the elevation of blood creatinine during cDDP intervention. These data indicate that Qu pretreatment potentiates the antitumor effects of cDDP in ovarian cancer while protecting the kidneys against damage. Therefore the strategy of Qu pretreatment may be beneficial in enhancing the therapeutic efficacy of cDDP against ovarian cancer.

Fungicidal activity of AKWATON and in vitro assessment of its toxic effects on animal cells

Acquired superficial fungal infections are among the most common infections. It is necessary to create new effective and non-toxic disinfectants. AKWATON is a new disinfectant of the polymeric guanidine family. Its fungicidal activity against Trichophyton mentagrophytes and its in vitro toxicity assessment were determined in this study. The MIC, minimum fungicidal concentration (MFC) and time required for its fungicidal activity at the MFC were evaluated using the official methods of analysis of the Association of Official Analytical Chemists, with modifications as recommended by the Canadian General Standards Board. The toxic effects of AKWATON and of four commercial disinfectants were evaluated on rat pancreatic (C2C12) and muscle (RnM5F) cells, using the trypan blue and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] methods. The MIC, MFC and time required for the fungicidal activity of AKWATON at the MFC were 0.025 % (w/v), 0.045 % (w/v) and 2.5 min, respectively. Cell cultures and the different tests carried out showed that the AKWATON-based disinfectant killed fewer cells than the commercial disinfectants, sparing 80 % of C2C12 cells and 65 % of RnM5F cells, whilst some of the well-known disinfectants currently on the market killed 85-100 % of cells. This study demonstrates that AKWATON has great potential as an odourless, colourless, non-corrosive and safe disinfectant for use in hospitals, the agriculture industry, farming and household facilities.

Rhubarb tannins extract inhibits the expression of aquaporins 2 and 3 in magnesium sulphate-induced diarrhoea model

Tannins, a group of major active components of Chinese rhubarb and widely distributed in nature, have a significant antidiarrhoeal activity. Aquaporins (AQPs) 2 and 3 play important roles in regulating water transfer during diarrhoea. The present study aims to determine the effect of the total tannins extract of rhubarb on aquaporins (AQPs) 2 and 3 in diarrhoea mice and HT-29 cells both induced by magnesium sulphate (MgSO₄). Our results showed that rhubarb tannins extract (RTE) significantly decreased the faecal water content in colon and evaluation index of defecation of diarrhoea mice. Interestingly, RTE could markedly reduce the mRNA and protein expression levels of AQPs 2 and 3 in apical and lateral mucosal epithelial cells in the colons of diarrhoea mice and HT-29 cells both induced by MgSO₄ in a dose-dependent manner. Furthermore, RTE suppressed the production of cyclic monophosphate- (cAMP-) dependent protein kinase A catalytic subunits α (PKA C-α) and phosphorylated cAMP response element-binding protein (p-CREB, Ser133) in MgSO₄-induced HT-29 cells. Our data showed for the first time that RTE inhibit AQPs 2 and 3 expression in vivo and in vitro via downregulating PKA/p-CREB signal pathway, which accounts for the antidiarrhoeal effect of RTE.

Antibacterial activities of Ligaria cuneifolia and Jodina rhombifolia leaf extracts against phytopathogenic and clinical bacteria

Six plant extracts prepared from Ligaria cuneifolia and Jodina rhombifolia were screened for their potential antimicrobial activities against phytopathogens and clinically standard reference bacterial strains. Bioautography and broth microdilution methods were used to study samples antibacterial activities against 7 bacterial strains. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of samples were attained. An antibacterial activity guided isolation and identification of active compounds was carried out for L. cuneifolia methanolic extract (LCME). Both methanolic and aqueous extracts from L. cuneifolia showed inhibitory activities against phytopathogenic bacteria, with MICs ranging from 2.5 to 156 μg mL(-1) for LCME and 5 mg mL(-1) for the aqueous extract. None of the three J. rhombifolia extracts showed significant antibacterial activities against phytopathogenic strains (MIC > 5 mg mL(-1)), except for the aqueous extracts against Pseudomonas syringae (MIC = 312 μg mL(-1)). Only LCME showed bactericidal activities against phytopathogenic strains (MBCs = 78 μg mL(-1)). The LCME exhibited significant inhibitory activity against reference clinical strains: Escherichia coli (MIC = 156 μg mL(-1)) and Staphylococcus aureus (MIC = 78 μg mL(-1), MBC = 312 μg mL(-1)). LCME active compounds were identified as flavonol mono and diglycosides, and gallic acid. The antibacterial activity of purified compounds was also evaluated. A synergistic effect against S. aureus was found between gallic acid and a quercetin glycoside. Hence, anti-phytopathogenic bacteria potential compounds isolated from L. cuneifolia could be used as an effective source against bacterial diseases in plants.

Quercitrin and taxifolin stimulate osteoblast differentiation in MC3T3-E1 cells and inhibit osteoclastogenesis in RAW 264.7 cells

Flavonoids are natural antioxidants that positively influence bone metabolism. The present study screened among different flavonoids to identify biomolecules for potential use in bone regeneration. For this purpose, we used MC3T3-E1 and RAW264.7 cells to evaluate their effect on cell viability and cell differentiation. First, different doses of chrysin, diosmetin, galangin, quercitrin and taxifolin were analyzed to determine the optimum concentration to induce osteoblast differentiation. After 48h of treatment, doses ≥100μM of diosmetin and galangin and also 500μM taxifolin revealed a toxic effect on cells. The same effect was observed in cells treated with doses ≥100μM of chrysin after 14 days of treatment. However, the safe doses of quercitrin (200 and 500μM) and taxifolin (100 and 200μM) induced bone sialoprotein and osteocalcin mRNA expression. Also higher osteocalcin secreted levels were determined in 100μM taxifolin osteoblast treated samples when compared with the control ones. On the other hand, quercitrin and taxifolin decreased Rankl gene expression in osteoblasts, suggesting an inhibition of osteoclast formation. Indeed, osteoclastogenesis suppression by quercitrin and taxifolin treatment was observed in RAW264.7 cells. Based on these findings, the present study demonstrates that quercitrin and taxifolin promote osteoblast differentiation in MC3T3-E1 cells and also inhibit osteoclastogenesis in RAW264.7 cells, showing a positive effect of these flavonoids on bone metabolism.

In vitro and in vivo antidermatophytic activity of the dichloromethane-methanol (1:1 v/v) extract from the stem bark of Polyscias fulva Hiern (Araliaceae)

Background

During the last decades, the number of people suffering from dermatophytoses has seriously increased, mainly due to the development of resistant strains of microorganisms to a range of formally efficient antibiotics. Polyscias fulva, a medium size tree which grows in the West Region of Cameroon is traditionally used for local application against dermatoses and orally against venereal infections. The dichloromethane-methanol (1:1 v/v) extract from the stem bark of Polyscias fulva was evaluated for its in vitro and in vivo antifungal activities.

Methods

The plant extract was prepared by maceration of its stem bark powder in CH₂Cl₂-MeOH (1:1 v/v). The extract obtained was successively partitioned in hexane, ethyl acetate and n-butanol. Phytochemical screening was performed using standard methods. In vitro antidermatophytic activity was assayed by the well diffusion and broth microdilution methods. The degree of dermal irritation of the crude extract was determined in guinea pigs using the occluded dermal irritation test method. The in vivo antidermatophytic activity of the extract-oil formulation (1.25, 2.5 and 5% w/w concentrations) was evaluated using Trichophyton mentagrophytes-induced dermatophytosis in a guinea pigs model.

Results

Phytochemical screening indicated that, the crude extract, ethyl acetate, n-butanol and residue fractions contain in general saponins, tannins, alkaloids, anthraquinones and phenols while the hexane fraction contains only alkaloids. The ethyl-acetate, n-butanol and residue fractions displayed higher antifungal activities (MIC = 0.125-0.5 mg.mL^-1) against eight dermatophytes as compared to the crude extract (MIC = 0.5-1 mg.mL^-1). This latter appeared to have slight perceptible erythema effects on guinea pigs as the primary irritation index (PII) was calculated to be 0.54. In vivo, the antidermatophytic activities of the extract-oil formulations were dose-dependent. Griseofulvin-oil 5% at 0.01 g/kg and formulated extract-oil (5%) at 0.1 g/kg eradicated the microbial infection after thirteen and fourteen days of daily treatment respectively.

Conclusions

The results of preclinical in vitro and in vivo evaluations indicate that the extract-oil formulation at 5% may constitute an alternative means to alleviate fungal infections caused by dermatophytes.

Quercitrin protects skin from UVB-induced oxidative damage

Exposure of the skin to ultraviolet B (UVB) radiation causes oxidative damage to skin, resulting in sunburn, photoaging, and skin cancer. It is generally believed that the skin damage induced by UV irradiation is a consequence of generation of reactive oxygen species (ROS). Recently, there is an increased interest in the use of natural products as chemopreventive agents for non-melanoma skin cancer (NMSC) due to their antioxidants and anti-inflammatory properties. Quercitrin, glycosylated form of quercetin, is the most common flavonoid in nature with antioxidant properties. The present study investigated the possible beneficial effects of quercitrin to inhibit UVB irradiation-induced oxidative damage in vitro and in vivo. Our results showed that quercitrin decreased ROS generation induced by UVB irradiation in JB6 cells. Quercitrin restored catalase expression and GSH/GSSG ratio reduced by UVB exposure, two major antioxidant enzymes, leading to reductions of oxidative DNA damage and apoptosis and protection of the skin from inflammation caused by UVB exposure. The present study demonstrated that quercitrin functions as an antioxidant against UVB irradiation-induced oxidative damage to skin.

Protective effect of 70% ethanolic extract of Lindera obtusiloba Blume on tert-butyl hydroperoxide-induced oxidative hepatotoxicity in rats

Lindera obtusiloba Blume, a native plant of East Asia, has traditionally been used as a folk medicine for liver disease. We studied the in vitro antioxidant and in vivo hepatoprotective activities of a 70% ethanolic extract of L. obtusiloba (LOE) containing 62.9% quercitrin and 22.0% afzelin. LOE prevented tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in HepG2 cells. Along with its high antioxidant potency in vitro, our animal study confirmed that pretreatment with LOE (500 or 2000 mg/kg) for 7 days prior to a single dose of t-BHP (i.p.: 0.5 mmol/kg) significantly lowered the serum levels of alanine and aspartate aminotransferases. In addition, glutathione levels were increased in the liver, and lipid peroxidation levels were decreased in a dose-dependent manner. The histopathological examinations of rat livers showed that LOE significantly reduced the incidence of liver lesions induced by t-BHP. Therefore, we concluded that LOE has merit as a potent candidate to protect the liver against oxidative damage.

Akwaton, polyhexamethylene-guanidine hydrochloride-based sporicidal disinfectant: a novel tool to fight bacterial spores and nosocomial infections

Bacterial spores are of continuing interest to the food and medical industries. In efforts to eliminate bacterial spore contamination, a number of sporicidal agents have been developed. Most of these compounds must be used carefully in very specific circumstances as they are toxic to humans. The sporicidal activity of Akwaton, a polyhexamethylene-guanidine hydrochloride (PHMGH)-based disinfectant, was tested against Bacillus subtilis spores. PHMGH is a colourless, odourless, non-corrosive and non-irritating antimicrobial biocide of the guanidine family. Spores suspended in distilled water and spores placed on solid surfaces (stainless steel and glass) were used to determine the log(10) reduction after exposure to varying concentrations of Akwaton. The minimum sporostatic concentration, the minimum sporicidal concentration and the time required for sporicidal activity corresponded to 0.06% (w/v), 0.08 % (w/v) and 8.5 min, respectively. Disinfectant concentrations of 0.24 % (w/v) and 0.44 % (w/v) killed all spores suspended in distilled water within 3 min and 90 s, respectively. The sporicidal activity against suspended spores was linearly dependent with respect to the concentration of PHMGH and contact time (y(3 min) = 40x-1.6 and y(90 s) = 20x-0.8 thus y(3 min) = 2y(90 s)). Spores placed on surfaces were more resistant to the effect of the disinfectant and the positive linear correlation between the sporicidal activity and concentration was not observed. The concentration required to kill all spores placed on a surface (stainless steel or glass) corresponded to 0.52 % (w/v) for 90 s of contact and 0.36 % (w/v) for 3 min. This study demonstrated that PHMGH is an effective sporicidal disinfectant with great potential for use in hospitals, laboratories, food industries and households.

Antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds from stem bark of Albizia adianthifolia (Mimosoideae)

BACKGROUND

Albizia adianthifolia is used traditionally in Cameroon to treat several ailments, including infectious and associated diseases. This work was therefore designed to investigate the antioxidant and antimicrobial activities of ethyl acetate extract, fractions and compounds isolated from the stem bark of this plant.

METHODS

The plant extract was prepared by maceration in ethyl acetate. Its fractionation was done by column chromatography and the structures of isolated compounds were elucidated using spectroscopic data in conjunction with literature data. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) and trolox equivalent antioxidant capacity (TEAC) assays were used to detect the antioxidant activity. Broth micro-dilution method was used for antimicrobial test. Total phenol content was determined spectrophotometrically in the extracts by using Folin-Ciocalteu method.

RESULTS

The fractionation of the extract afforded two known compounds: lupeol (1) and aurantiamide acetate (2) together with two mixtures of fatty acids: oleic acid and n-hexadecanoic acid (B₁); n-hexadecanoic acid, octadecanoic acid and docosanoic acid (B₂). Aurantiamide acetate was the most active compound. The total phenol concentration expressed as gallic acid equivalents (GAE) was found to vary from 1.50 to 13.49 μg/ml in the extracts. The antioxidant activities were well correlated with the total phenol content (R² = 0.946 for the TEAC method and R² = 0.980 for the DPPH free-radical scavenging assay).

CONCLUSIONS

Our results clearly reveal that the ethyl acetate extract from the stem bark of A. adianthifolia possesses antioxidant and antimicrobial principles. The antioxidant activity of this extract as well as that of compound 2 are being reported herein for the first time. These results provide promising baseline information for the potential use of this plant as well as compound 2 in the treatment of oxidative damage and infections associated with the studied microorganisms.

Antimicrobial activities of polyhexamethylene guanidine hydrochloride-based disinfectant against fungi isolated from cocoa beans and reference strains of bacteria

This study was conducted to assess the antibacterial and the antifungal activity of a polyhexamethylene guanidine hydrochloride (PHMGH)-based disinfectant and to determine if it could be used as a disinfectant for the treatment of cocoa beans. The activity of PHMGH was tested in vitro for efficacy against five reference strains of pathogenic bacteria and six strains of fungi isolated from cocoa beans. All the strains tested were sensitive to the disinfectant. The MICs reported were between 0.01 and 1.9 mg/ml and equal to the MBC or minimum fungicidal concentration (MFC) regardless of the strains of those microorganisms. The bacteria were more sensitive to PHMGH than were the fungi. Enterobacter cloacae was the most sensitive bacterium with a MIC and MBC of 0.01 mg/ml, whereas the genus Aspergillus was the least susceptible of the microorganisms tested, with a MIC and MFC from 1.0 to 1.9 mg/ml. The time required for the activity of PHMGH varies from 2 min for Enterobacter cloacae to 12 min for Aspergillus tamarii and generally increases with the MBC or the MFC. Through this in vitro study, the PHMGH has been proved to be bactericidal and fungicidal on the strains studied. Hence, it could probably serve as a fungicidal disinfectant for the treatment of cocoa beans after harvesting.

Antidiarrheal activity of extracts and compound from Trilepisium madagascariense stem bark

Objective:

The present study was performed to evaluate the preventive and curative antidiarrheal effects of the methanol extract, fractions and compound from the stem bark of Trilepisium madagascariense in rats.

Materials and Methods:

The methanol extract from the stem bark of T. madagascariense, its fractions (n-hexane, ethyl acetate, n-butanol and aqueous residue) and compound (obtained from further column chromatography of the ethyl acetate fraction) were evaluated for the antidiarrheal activity in rats. These test samples (at 100, 200 and 400 mg/kg for the extract and fractions and 2.5 mg/kg for compound) were assayed on the latent periods, purging indices and fecal frequencies in castor oil-induced diarrhea. Gastrointestinal transit and castor oil-induced enteropooling assays were conducted. Shigella-induced diarrhea was assayed. Blood chemistry and fecal Shigella load were examined.

Results:

The fractionation of the ethyl acetate fraction from the methanol extract of T. madagascariense afforded a known compound [isoliquiritigenin (1)]. Compound 1 increased the latent period of diarrhea induction (179.40 min) compared to the saline control (60.80 min). The purging indices, fecal frequencies and intestinal enteropooling decreased with an increase in the dose of test samples. The blood cell counts, sera creatinine and fecal Shigella load decreased significantly (P ≤ 0.05) in the plant extract-treated rats compared to the saline control.

Conclusion:

The results of our study, being reported for the first time, provide clear evidence that the methanol extract, fractions and isoliquiritigenin from T. madagascariense stem bark possess antidiarrheal activities.

Protective effect of quercitrin against hydrogen peroxide-induced dysfunction in osteoblastic MC3T3-E1 cells

The protective effect of quercitrin on the response of osteoblastic MC3T3-E1 cells to oxidative stress was evaluated. Osteoblasts were incubated with H(2)O(2) and/or quercitrin, and markers of osteoblast function and oxidative damage were examined. Quercitrin treatment reversed the cytotoxic effect of H(2)O(2) significantly (P<0.05). This effect was blocked by ICI182780 and LY294002, suggesting that quercitrin's effect might be involved in estrogen action and results from PI3K mediated signaling pathway. Pretreatment of quercitrin increased collagen content, alkaline phosphatase (ALP) activity, and calcium deposition of osteoblasts compared with H(2)O(2) treated cells and these effects were blocked by ERKs and p38 mitogen-activated protein kinases (MAPKs) inhibitors such as PD98059 and SB203580, respectively. These suggest that quercitrin-induced protective effect against osteoblast dysfunction by oxidative stress is associated with increased activation of ERKs and p38 MAPK. Pretreatment with quercitrin also reduced the increase in bone-resorbing factor, receptor activator of nuclear factor-kB ligand (RANKL) and oxidative damage markers (malondialdehyde, protein carbonyl, and nitrotyrosine) induced by H(2)O(2). These results suggest that quercitrin may be protective against H(2)O(2)-induced dysfunction in osteoblasts.

Free radical scavenging activities and inhibition of inflammatory enzymes of phenolics isolated from Tripodanthus acutifolius

ETHNOPHARMACOLOGICAL RELEVANCE

Leaf extracts from Tripodanthus acutifolius (Ruiz and Pavón) Van Tieghem have long been used in Argentinean traditional medicine as anti-inflammatory, however, there is no scientific evidence which supports this use in the literature.

AIM OF THE STUDY

The present study was conducted to evaluate the ability of five phenolic compounds purified from infusion prepared from Tripodanthus acutifolius leaves to inhibit key enzymes in inflammatory processes. As anti-inflammatory compounds frequently possess free radical scavenging activities, purified substances were comparatively evaluated to asses their free radical scavenging properties. Genotoxic effects were also evaluated.

MATERIALS AND METHODS

Compounds were evaluated on their ability to inhibit hyaluronidase and cyclooxygenase-2 (COX-2) activities to assess their anti-inflammatory capacities. Free radical scavenging activity was assessed by: 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH), superoxide anion assay and the inhibition on lipid peroxidation. Genotoxicity was evaluated by Bacillus subtilis rec assay.

RESULTS

Fractionation of Tripodanthus acutifolius infusion yielded a novel phenylbutanoid derivative (tripodantoside) and four known flavonoid glycosides (rutin, nicotiflorin, hyperoside and isoquercitrin). Flavonoids produced higher inhibition on hyluronidase activity (IC(50) approximately 1.7 mM) than tripodantoside (IC(50)=27.90 mM). A similar COX-2 inhibition activity was exerted by tripodantoside and monoglycosilated flavonoids (IC(50) approximately 50 microM). Compounds were strong radical scavengers, with effective concentration 50 (EC(50)) values for DPPH in the range of 2.7-6.3 microg/mL, and for superoxide anion in the range of 3.9-8.7 microg/mL. All compounds scavenged peroxyl radicals in the lipid peroxidation assay. The substances showed no genotoxic effects.

CONCLUSIONS

The anti-inflammatory effects, free radical scavenging activities and lack of genotoxicity of purified compounds may support the folk use of infusion from Tripodanthus acutifolius leaves as anti-inflammatory.