Promising Extracts Research Articles

Isolation and synthesis of pygmanilines, phenylurea derivatives from the Northeastern Atlantic lichen Lichina pygmaea

A library of 864 extracts prepared from Irish marine organisms was screened in the search for novel antioxidants. Chemical investigation of the most promising extract obtained from the common lichen Lichina pygmaea led to the isolation of five resorcinol derivatives. An unusual urea moiety was found embedded in two of these compounds, pygmanilines A (1) and B (2) and their structures were confirmed by one-step chemical syntheses.

In vitro antibacterial activity and in vivo therapeutic effect of Sesbania grandiflora in bacterial infected silkworms

Context: Antibiotic resistance is a serious problem worldwide. Searching for new potential agents is, therefore, essential. The bark of Sesbania grandiflora (L.) Pers. (Fabaceae) has been used in folk medicine against various diseases. Objective: To investigate the antibacterial activity of S. grandiflora bark and explore the therapeutic effect of the highest potent fraction. Materials and methods: Bacteria and healthy silkworms were exposed to three fractionated extracts (3.1–400 mg/mL) of S. grandiflora bark from hexane (HXF), chloroform (CFF), and ethyl acetate (EAF). The sets of bacteria were incubated at 37 °C while silkworms were kept at 27 °C for 24 h. To evaluate the therapeutic effect, silkworms infected with bacteria were exposed to the extracts (0.5–60 mg/mL) and incubated at 27 °C for 52 h. Qualitative analysis of the most potent extract was done using HPLC. Results: EAF showed the highest activity with MIC against methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci (VRE) of 1.6 and 0.4 mg/mL, respectively, and against Gram-negative Escherichia coli and Pseudomonas aeruginosa of 6.2 and 3.1 mg/mL, respectively. It is nontoxic to silkworms with LC50 >400 mg/mL and has high therapeutic effect on infected silkworms with EC50 of 1.9 mg/mL. EAF consists of at least five major compounds, one of them is gallic acid. The activity of EAF is higher than the sum of individual activities of separated compounds. Discussion and conclusion: These results suggest that EAF is a promising antibacterial extract, suitable for further investigation in rodents infected with drug resistant bacteria.

Effects of Caesalpinia sappan on pathogenic bacteria causing dental caries and gingivitis.

The present study explores antimicrobial activities of Caesalpinia sappan extracts against three strains of oral pathogenic bacteria; Streptococcus mutans DMST9567 (Smu9), Streptococcus mutans DMST41283 (Smu4), and Streptococcus intermedius DMST42700 (Si). Ethanol crude extract of C. sappan (Cs-EtOH) was firstly compared to that of other medicinal plants using disc diffusion method. Cs-EtOH showed significantly higher effective inhibition against all tested strains than other extracts and 0.12% chlorhexidine with the inhibition zone of 17.5 ± 0.5, 18.5 ± 0.0, and 17.0 ± 0.0 mm against Smu9, Smu4, and Si, respectively. Three fractionated extracts of C. sappan using hexane, ethyl acetate, and ethanol, respectively, were further investigated. The fractionated extract from ethanol (F-EtOH) presented the strongest activities with the minimum bactericidal concentration (MBC) of 125-250 µg/mL. Killing kinetics of F-EtOH was depended on the bacterial species and the concentration of F-EtOH. Two-fold MBC of F-EtOH could kill all tested strains within 12 h whereas its 4-fold MBC showed killing effect against Si within 6 h. Separation of F-EtOH by column chromatography using chloroform/methanol mixture as an eluent yielded 11 fractions (F1-F11). The fingerprints of these fractions by high-performance liquid chromatography at 280 nm revealed that F-EtOH consisted of at least 5 compounds. F6 possessed the significantly highest antimicrobial activity among 11 fractions, however less than F-EtOH. It is considered that F-EtOH is the promising extract of C. sappan for inhibiting oral pathogenic bacteria and appropriate as natural antiseptic for further develop of oral hygiene products.

Potential of Piper betle extracts on inhibition of oral pathogens.

In the present study, antimicrobial activity of Piper betle crude ethanol extract against 4 strains of oral pathogens; Candida albicans DMST 8684, C. albicans DMST 5815, Streptococcus gordonii DMST 38731 and Streptococcus mutans DMST 18777 was compared with other medicinal plants. P. betle showed the strongest antimicrobial activity against all tested strains. Fractionated extracts of P. betle using hexane, ethyl acetate, and ethanol, respectively, were subjected to antimicrobial assay. The result revealed that the fractionated extract from ethyl acetate (F-EtOAc) possessed the strongest antimicrobial activity against all tested strains. Its inhibition zones against those pathogens were 23.00 ± 0.00, 24.33 ± 0.58, 12.50 ± 0.70 and 11.00 ± 0.00 mm, respectively and its minimum inhibitory concentrations were 0.50, 1.00, 0.50 and 1.00 mg/mL, respectively. Interestingly, the minimum concentration to completely kill those pathogens was the same for all strains and found to be 2.00 mg/mL. Killing kinetic study revealed that the activity of F-EtOAc was dose dependent. HPLC chromatograms of P. betle extracts were compared with its antimicrobial activity. An obvious peak at a retention time of 4.11 min was found to be a major component of F-EtOAc whereas it was a minor compound in the other extracts. This peak was considered to be an active compound of P. betle as it was consistent with the antimicrobial activity of F-EtOAc, the most potential extract against the tested pathogens. It is suggested that F-EtOAc is a promising extract of P. betle for inhibition of oral pathogens. Separation and structure elucidation of the active compound of this extract will be further investigated.

The correlation between antimutagenic activity and total phenolic content of extracts of 31 plant species with high antioxidant activity.

BackgroundAntimutagenic activity of plant extracts is important in the discovery of new, effective cancer preventing agents. There is increasing evidence that cancer and other mutation-related diseases can be prevented by intake of DNA protective agents. The identification of antimutagenic agents present in plants presents an effective strategy to inhibit pathogenic processes resulting from exposure to mutagenic and/or carcinogenic substances present in the environment. There are no reports on the antimutagenic activities of the plant species investigated in this study. Many mutations related to oxidative stress and DNA damage by reactive oxygen species (ROS) and reactive nitrogen species (RNS) have been identified in numerous human syndromes. Oxidative DNA damage plays a significant role in mutagenesis, cancer, aging and other human pathologies. Since oxidative DNA damage plays a role in the pathogenesis of several chronic degenerative diseases, the decrease of the oxidative stress could be the best possible strategy for prevention of these diseases. Antioxidant compounds can play a preventative role against mutation-related diseases, and thus have potential antimutagenic effects.MethodsThe number of antioxidant compounds present in methanol leaf extracts of 120 plant species was determined using a combination of Thin Layer Chromatography (TLC) and spraying with 2, 2-diphenyl-1-picrylhydrazyl (DPPH). The 31 most promising extracts were selected for further assays. The quantitative antioxidant activity was determined using DPPH free radical scavenging spectrophotometric assay. Total phenolic contents were determined using the Folin-Ciocalteu colorimetric assay. The mutagenicity of 31 selected extracts was determined in the Ames test using Salmonella typhimurium strains TA98 and TA100. The antimutagenicity of the plant extracts against 4-nitroquinoline 1-oxide (4-NQO) was also determined using the Ames test.ResultsOf the 120 plant extracts assayed qualitatively, 117 had some antioxidant activity. The selected 31 extracts contained well defined antioxidant compounds. These species had good DPPH free radical antioxidant activity with EC50 values ranging from 1.20 to 19.06 μg/ml. Some of the plant extracts had higher antioxidant activity than L-ascorbic acid (vitamin C). The total phenolic contents ranged from 5.17 to 18.65 mg GAE (gallic acid equivalent)/g plant extract). The total phenolic content of the plant extracts correlated well with the respective antioxidant activity of the plant extracts. No plant extract with good antioxidant activity had mutagenic activity. Several extracts had antimutagenic activity. The percentage inhibition of 4-NQO ranged from 0.8 to 77% in Salmonella typhimurium TA98 and from 0.8 to 99% in strain TA100. There was a direct correlation between the presence of antioxidant activity and antimutagenic activity of the plant extracts. Although no plant extract had mutagenic activity on its own, some of the plant extracts enhanced the mutagenicity of 4-NQO, a phenomenon referred to as comutagenicity.ConclusionsSome of the plant extracts investigated in this study had potential antimutagenic activities. The antimutagenic activities may be associated with the presence of antioxidant polyphenols in the extracts. From the results plant extracts were identified that were not mutagenic, not cytotoxic and that may be antimutagenic in the Ames test. For most plant extracts, at the highest concentration used (5 mg/ml), the level of antimutagenicity was below the recommended 45% to conclude whether plants have good antimutagenic activity. However, in most screening studies for antimutagenesis, a 20% decrease in the number of revertants must be obtained in order to score the extract as active. Psoralea pinnata L. had the highest percentage antimutagenicity recorded in this study (76.67 and 99.83% in S. typhimurium TA98 and TA100 respectively) at assayed concentration of 5 mg/ml.The results indicate that investigating antioxidant activity and the number of antioxidant compounds in plant extracts could be a viable option in searching for antimutagenic compounds in plants.Electronic supplementary materialThe online version of this article (doi:10.1186/s12906-016-1437-x) contains supplementary material, which is available to authorized users.

The Fractionated Toona sinensis Leaf Extract Induces Apoptosis of Human Osteosarcoma Cells and Inhibits Tumor Growth in a Murine Xenograft Model.

Background: Osteosarcoma is a malignant bone tumor prevalent in adolescents with poor prognosis. Toona sinensis showed potent antiproliferation effect on lung, melatonin, ovary, colon, and liver cancers. However, the effects of the species on osteosarcoma cells are rarely investigated. Results: In this study, we found fraction 1 of Toona sinensis leaf (TSL-1) resulted in inhibition of cell viability in MG-63, Saos-2, and U2OS osteosarcoma cell lines, while it only caused a moderate suppressive effect on normal osteoblasts. In addition, TSL-1 significantly elevated lactate dehydrogenase leakage and induced apoptosis and necrosis in Saos-2 cells. TSL-1 increased mRNA expression of pro-apoptotic factor Bad. Most important, TSL-1 significantly suppressed Saos-2 xenograft tumor growth in nude mice by increasing caspase-3. The IC-50 of TSL-1 for the 3 tested osteosarcoma cells is around 1/9 of that for lung cancer cells. Conclusion: We demonstrated that TSL-1, a fractionated extract from TSL, caused significant cytotoxicity to osteosarcoma cells due to apoptosis. In vivo xenograft study showed that TSL-1 suppressed the growth of osteosarcoma cells at least in part by inducing apoptosis. Our results indicate that TSL-1 has potential to be a promising anti-osteosarcoma adjuvant functional plant extract.

Macroalgal activity against multiple drug resistant Aeromonas hydrophila: A novel treatment study towards enhancement of fish growth performance

ObjectiveThe aim of this study was to evaluate the efficiency of macroalgal extracts as antibacterial agent against multidrug-resistant (MDR) bacteria isolated from Nile tilapia (Oreochromis niloticus) as well as to enhance the fish growth performance by macroalgae diet application. MethodsA total of 50 swabs were collected from the diseased organs of tilapia fish including gills, skin, spleen, intestine, liver, kidney and muscle. The isolated bacteria were identified and then confirmed by using VITEK 2. Eight macroalgal species were collected from Abu-Qir, Alexandria coast, Egypt. After determination of their biomass, three solvents were used to prepare algal extracts. The antibacterial activities of different macroalgal extracts were measured against MDR Aeromonas hydrophila 6 (MDRAH6) using well-diffusion method. The mechanism by which macroalgal extract affects MDR bacteria was conducted by using transmission electron microscope (TEM). To evaluate the safety of the promising algal extract, GC-MS was performed to detect the composition of S. vulgare extract. In addition, growth performance was measured as an application of algal extracts into fish feed. ResultsBetween eight collected macroalgal species, Sargassum vulgare showed the highest biomass production (53.4 g m−2). In addition, its ethanolic extract showed the highest significant antibacterial activity with MIC value of 250 μg ml−1. TEM examination showed distinctive changes in the treated MDRAH6 cells including rupture of the cell wall, leakage of cytoplasmic contents, alterations in the cytoplasm density in addition to totally cell deformation. In addition, GC-MS analysis revealed eleven identified components in S. vulgare ethanolic extract, in which 9,12-octadecadienoyl chloride and hexadecanoic acid methyl ester were dominant (46.6 and 19.7 %, respectively). Furthermore, dietary replacement of fish meal with S. vulgare ethanolic extract significantly enhanced the growth performance and survival of Nile tilapia with a significant reduction in the total bacterial count. ConclusionEthanol extract of the brown macroalga S. vulgare could be a promising antibacterial and a new active agent against MDR A. hydrophila, which could be a major causative agent of Nile tilapia fish diseases. In addition, this study recommended S. vulgare as a natural and effective source to enhance the growth performance of Nile tilapia. In fact, isolation and examination of the individual antibacterial active compounds of the S. vulgar ethanolic extract are under investigation.

Evaluation of therapeutic potentials of plant extracts against poultry bacteria threatening public health.

BackgroundPlant extracts were evaluated on poultry bacteria known to be threatening public health. This is to develop better bio-therapeutic agents from plant origin.MethodsBacteria were isolated from water, feed, crop, gizzard and faeces of layer chicken. Isolates of interest (Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa and Klebsiella oxytoca) were subjected to antibiotic susceptibility test. Resistant strains were further evaluated against different plant extracts in comparison to Meropenem (control) using agar diffusion method.Results E. coli had the highest occurrence (53 %), followed by P. aeruginosa (25 %) and then S. enteritidis (13 %) while the least was K. oxytoca (9 %). Virtually all the isolates exhibited multi-antibiotic resistance (MAR) with gross resistance to Amoxicillin, Erythromycin and Cefuroxine. P. aeruginosa (75 %), S. enteritidis (75 %) and E. coli (63 %), had the highest MAR. Out of the 11 (100 %) plant extracts evaluated, 7 (64 %) were outstanding and showed varied levels of antibacterial activity. Specifically, methanol extract of Mangifera indica Julie cultivar leaf (MJLM) had the highest antibacterial activity, followed by Euadenia trifoliata stem bark (TB03) and Euadenia eminens leaf (TB05). P. aeruginosa was highly susceptible (81.81 %) to the extracts, followed by S. enteritidis (63.64 %) and then E. coli (27.27 %).ConclusionsMJLM and other extracts have proven to be promising extracts in which to search for bioactive components that can be developed into therapeutic drugs. This may help in the management of antibiotic resistant bacterial isolates from poultry chicken threatening public health.

Green Extraction from Pomegranate Marcs for the Production of Functional Foods and Cosmetics.

The aim of this study was to investigate the potential of retrieving polyphenolic antioxidants directly from wet pomegranate marcs: the fresh by-products obtained after pomegranate juice processing. These by-products mainly consist of internal membranes (endocarp) and aril residues. Even if they are still edible, they are usually discharged during juice production and, thus, they represent a great challenge in an eco-sustainable industrial context. Green technologies, such as ultrasound assisted extraction (UAE) and microwave assisted extraction (MAE), have been employed to convert these organic residues into recycled products with high added value. UAE and MAE were used both in parallel and in series in order to make a comparison and to ensure exhaustive extractions, respectively. Water, as an environmentally friendly extraction solvent, has been employed. The results were compared with those ones coming from a conventional extraction. The most promising extract, in terms of total polyphenol yield and radical scavenging activity, has been tested both as a potential natural additive and as a functional ingredient after its incorporation in a real food model and in a real cosmetic matrix, respectively. This study represents a proposal to the agro-alimentary sector given the general need of environmental “responsible care”.

Extraction, characterization and evaluation of Kaempferia galanga L. (Zingiberaceae) rhizome extracts against acute and chronic inflammation in rats

Ethnopharmacological relevanceThe rhizomes of an acaulescent perennial herb, Kaempferia galanga Linn (Family: Zingiberaceae), used as traditional ayurvedic herb to get relief from indigestion, swelling, pain, high blood pressure and dyslipidemia. Aim of the studyTo prepare and characterize various extracts of Kaempferia galanga (K. galanga) for their comparative evaluation for the identification of the most efficacious extract and its possible pharmacological implication in acute and chronic inflammatory paradigm. Materials and methodsDried and powdered rhizome of K. galanga was subjected to alcoholic extraction as well as successive extractions with various solvents. After phytochemical characterization, all the extracts were standardized for the presence of ethyl-p-methoxycinnamate. The extracts, and the isolated compound, were tested against carrageenan-induced acute inflammation in rats. The most promising extract was tested against adjuvant-induced chronic inflammation in rats. Further, local myeloperoxidase (MPO) levels were investigated to establish the possible mechanism of action. ResultsAmong the extracts, petroleum ether extract (SKG-1) and crude alcoholic extract (KG) had the maximum quantity of ethyl-p-methoxycinnamate. SKG-1 (300mg/kg) was found effective against acute inflammation in rats. Further, SKG-1 (100mg/kg) reversed the inflammation and elevated MPO levels found in the chronic model. ConclusionsThe results suggest that among all the extracts of K. galanga, SKG-1 effectively suppresses the progression of acute and chronic inflammation in rats by inhibition of neutrophil infiltration.

Evaluation of Ajuga bracteosa for antioxidant, anti-inflammatory, analgesic, antidepressant and anticoagulant activities.

BackgroundAjuga bracteosa has been extensively used traditionally for the treatment of a variety of diseases. The aim of the study was to scientifically validate the wide-scale exploitation of A. bracteosa in folk medicine various in vitro and in vivo assays. Moreover, these activities were related to the intrinsic biologically active phytoecdysteroids of A. bracteosa.MethodsAerial and root parts of A. bracteosa were first extracted separately with chloroform (AbCA and AbCR) and the residue was again extracted with methanol (AbMA and AbMR). Total flavonoid and phenolic contents were assayed as quercetin (QE) and gallic acid equivalents (GAE), respectively. These extracts were analyzed for in vitro antioxidant assessment including DPPH and H2O2 (% inhibition of free radicals), and reducing power and phosphomolybdenum methods (ascorbic acid equivalents AAE mg/g DW). Further, these extracts were assayed in vivo in separate groups of Sprague–Dawley rats for carrageenan induced rat paw edema inhibition, hotplate antinociception, forced swim antidepression and anticoagulation. Dose of each crude extract and standard drug given to rats was 200 mg/Kg- and 10 mg/10 mL/Kg body weight respectively. Plant extracts and standard drugs were administered orally, 60 min prior to the conduction of assays. Moreover, biologically active phytoecdysteroids were screened in A. bracteosa with the help of RP-HPLC.ResultsAbMA represented highest values of flavonoids (QE 1.98 % DW) and phenolic contents (GAE 5.94 % DW), significantly scavenged DPPH radicles (IC50 36.9) and reduced ferric ions with 718.4 mg ascorbic acid equivalent/g (AAE). Highest total antioxidant capacity was expressed by AbMR (927 mg AAE) with an IC50 value 19.1 μg/mL. The extracts which were found potent anti-oxidants, were also good at in vivo activities. AbMA significantly reduced edema in all the three hours of treatment (67.9, 70.3 and 74.3 %). AbMA also showed maximum nociceptor suppression in analgesic assay by delaying the time to start licking of paws in rats (57.7 ± 4.9 s). In addition, maximum anti-coagulation was also exhibited by AbMA (89.3 s), while all extracts were found strong antidepressants (≤15.66 s immobility time). Screening of biologically active phytoecdysteroids revealed the presence of 20-hydroxyecdysone (20-HE), makisterone (MKA), cyasterone (CYP) and ajujalactone (AJL). Total phytoecdysteroid content found in A. bracteosa was 1232.5 μg/g DW and 20-HE was most abundant (1232.5 μg/g DW) as compared to other phytoecdysteroids.ConclusionBased on the tested in vitro and in vivo activities, AbMA was found to be a promising bioactive extract. These activities can be attributed to the intrinsic polyphenols and phytoecdysteroids contents of A. bracteosa.

In vitro antibacterial and antifungal activities of twelve sponges collected from the Anambas Islands, Indonesia

ObjectiveTo evaluate antimicrobial activities in methanolic extracts of twelve sponges collected from the Anambas Islands, Indonesia. MethodsThe antibacterial activity of methanolic extracts was tested against two Gram-positive bacteria, viz. Bacillus subtilis (ATCC 6633) and Staphylococcus aureus (ATCC 25923), and two Gram-negative bacteria, viz. Eschericia coli (ATCC 25922) and Vibrio anguillarum (ATCC 19264) using the disk diffusion assay. The antifungal activity was similarly tested against Candida albicans (ATCC 10231) and Aspergillus niger (ATCC 16404). The minimum inhibitory concentrations of promising sponges extracts were determined by the microdilution technique. ResultsAll the sponge species in this study showed antimicrobial activities against at least one of the test strains. Antibacterial activities were observed in 66.7% of the sponges extracts, while 30.0% of the extracts exhibited antifungal activities. Among them, the extracts of the sponges Stylissa massa and Axinyssa sp. were the most active against four tested bacteria and the yeast Candida albicans. The sponge Theonella swinhoei and two species of Xestospongia also displayed significant activities against two fungal pathogens Candida albicans and Aspergillus niger. ConclusionsAntimicrobial activities were demonstrated in extracts from various marine sponges collected from the Anambas Islands, Indonesia. The most promising sponges among them were Stylissa massa and Axinyssa sp. This is the first report of antimicrobial activity in extracts of marine sponges from the Indonesian Anambas Islands.

Comparative analyses and evaluation of the cosmeceutical potential of selected Chlorella strains

In the present study, aqueous extracts from eight Chlorella strains were evaluated towards selected cosmeceutical properties such as enzymatic and non-enzymatic antioxidant capacity, glutathione content, inhibition potency towards skin regulatory enzymes, and cytotoxic effect on human cell lines. The results showed that the Chlorella strains display wide catalytic diversity with different strains exhibiting quite varied antioxidant enzymatic activities. The enzymes glutathione reductase, peroxidase, and superoxide dismutase were found in all strains, whereas only Chlorella minutissima displays glutathione transferase activity. Total antioxidant capacity (TAC) measurements, using the FRAP, ABTS, and DPPH assays, indicated significant differences among strains suggesting a large chemical diversity of antioxidants in Chlorella species. Chlorella minutissima extract showed high inhibitory potency with IC50 23.3 ± 2.5 and 29.2±2.7 μg towards tyrosinase and elastase, respectively, suggesting a potential activity in controlling skin aging, inflammatory process, and pigmentation. Furthermore, the effect of C. minutissima extract on a human hepatoma cell line (Huh-7) was evaluated using cell proliferation assay and qRT-PCR to analyze the expression of marker genes (SOD1, GPx1, GPx2) involved in oxidative stress response. The results established the absence of cytotoxic effects of the aqueous extracts. SOD1, GPx1, and GPx4 expression levels showed a specific profile and appear to be slightly upregulated, downregulated, and remained unaffected, respectively. Taken together, these results demonstrate that Chlorella species can provide promising extracts rich in antioxidants, anti-aging, and skin-whitening ingredients with the potential for use as raw material in cosmetics industry.

Angelica dahurica Extracts Improve Glucose Tolerance through the Activation of GPR119.

G protein-coupled receptor (GPR) 119 is expressed in pancreatic β-cells and intestinal L cells, and is involved in glucose-stimulated insulin secretion and glucagon-like peptide-1 (GLP-1) release, respectively. Therefore, the development of GPR119 agonists is a potential treatment for type 2 diabetes. We screened 1500 natural plant extracts for GPR119 agonistic actions and investigated the most promising extract, that from Angelica dahurica (AD), for hypoglycemic actions in vitro and in vivo. Human GPR119 activation was measured in GeneBLAzer T-Rex GPR119-CRE-bla CHO-K1 cells; intracellular cAMP levels and insulin secretion were measured in INS-1 cells; and GLP-1 release was measured in GLUTag cells. Glucose tolerance tests and serum plasma insulin levels were measured in normal C57BL6 mice and diabetic db/db mice. AD extract-treated cells showed significant increases in GPR119 activation, intracellular cAMP levels, GLP-1 levels and glucose-stimulated insulin secretion as compared with controls. In normal mice, a single treatment with AD extract improved glucose tolerance and increased insulin secretion. Treatment with multiple doses of AD extract or n-hexane fraction improved glucose tolerance in diabetic db/db mice. Imperatorin, phellopterin and isoimperatorin were identified in the active fraction of AD extract. Among these, phellopterin activated GPR119 and increased active GLP-1 and insulin secretion in vitro and enhanced glucose tolerance in normal and db/db mice. We suggest that phellopterin might have a therapeutic potential for the treatment of type 2 diabetes.

Screening of Botanical Extracts for Repellence against Western Corn Rootworm Larvae

The ability of western corn rootworm (WCR) (Diabrotica virgifera virgifera LeConte) to develop resistance to various management practices requires the development of new management options. Repellent extracts can act as efficacy enhancing agents in WCR control. The present study investigated the potential repellence of garlic (Allium sativum L.), pepper (Capsicum sp. L), cape aloe (Aloe ferox Mill.), neem (Azadirachta indica A. Juss) and turmeric (Curcuma longa L.) derived extracts against WCR larvae in a no-choice bioassays. In initial screenings garlic and turmeric were evaluated as the most promising extracts as WCR larvae avoided garlic / turmeric treated soil. Turmeric was further evaluated in a rhizotron set up to quantify larval distribution and behavioral changes over time. WCR larvae avoided turmeric treated soil up to 0.05 m from its application in the root system, resulting in an increased dispersal and the formation of multiple clusters in the rhizotron. The proportion of larvae actively moving in the soil subsequently increased, whereas larval feeding significantly decreased. The spatial and behavioral alterations in the soil lead to the conclusion that turmeric is a repellent extract for WCR larvae. Turmeric repellence might further be exploited for WCR management through a synergy with insecticidal substances or microbial antagonists.

Antibacterial and Anticancer Properties of Boswellia carteri Birdw. and Commiphora molmol Engl. Oleo-Resin Solvent Extractions

Background: Boswellia carteri Birdw. (frankincense) and Commiphora molmol Engl. (myrrh) oleo-resins have traditionally been used for the growth inhibition of bacteria associated with skin diseases, urinary tract infections, respiratory infections, wound healing, dental disease and gastrointestinal disorders. Despite this, many bacterial pathogens are yet to be screened for susceptibility to frankincense and myrrh extracts. This study was undertaken to test extracts prepared from frankincense and myrrholeo-resins for the ability to inhibit microbial and cancer cell growth. Materials and Methods: Frankincense and myrrhresins were extracted and tested for antimicrobial activity using modified disc diffusion and MIC methods. Inhibitory activity against CaCo2 and HeLa cancer cell lines was evaluated using colorimetric cell proliferation assays. Toxicity was evaluated using an Artemia franciscana nauplii bioassay. The most promising inhibitory extracts were investigated using non-targeted GC-MS head space analysis (with screening against a compound database) for the identification and characterisation of individual components in the crude plant extracts. Results: The frankincense and myrrh extracts displayed broad spectrum antibacterial activity, inhibiting the growth of all of the bacteria screened against. The frankincense extracts were generally more potent growth inhibitors than were the corresponding myrrh extracts. The growth inhibition of the methanolic, ethyl acetate and hexane frankincense extracts against Salmonella salford was particularly noteworthy, with MIC values of 462, 258 and 293 µg/mL respectively. The frankincense and myrrh extracts were both approximately equally effective against gram positive and gram negative bacteria. The majority of the extracts also proved effective at blocking the proliferation of the colorectal cancer cell line CaCo2 and HeLa cervical cancer cell growth, although the aqueous and ethyl acetate frankincense extracts generally had the greatest efficacy (IC50 values 1600-1900 µg/mL). All extracts were non-toxic, with LC50 values substantially > 1000 µg/mL. Conclusion: These studies validate traditional usage of frankincense and myrrh in the treatment of several bacterial illnesses and some cancers, and indicate that they are safe for therapeutic usage.

Inhibitory Action of Biofungicide Physcion on Initial and Secondary Infection of Magnaporthe oryzae

AbstractRice blast, caused by the ascomycete fungus Magnaporthe oryzae, is one of the most destructive plant diseases in the world and a serious threat to global food security. Biofungicide physcion, extracted from roots of Chinese traditional herb rhubarb, has been commercialized to control cucumber powdery mildew (Podosphaera fuliginea) in China as a new active and environmentally‐friendly ingredient. This study investigated its bioactivity on rice blast and impact on the infection of M. oryzae. Physcion was effective on M. oryzae with 50% inhibition concentration of 18.19 mg/l on the fungus mycelium growth in vitro and provided 86 and 98% control efficacy in vivo at the concentrations of 40 and 60 mg/l, respectively. It inhibited the initial infection of M. oryzae by inhibiting growth of mycelia, the germination of conidia and the formation of appressoria. Moreover, it inhibited the secondary infection of the fungus at the concentration of 40 mg/l, but had no influence at the low concentrations of 1.25–20 mg/l. So physcion might be a promising natural plant extract that is worthy of being explored to apply on the control of rice blast.

In Vitro Activity of Selected West African Medicinal Plants against Mycobacterium ulcerans Disease.

Buruli ulcer (BU) is the third most prevalent mycobacteriosis, after tuberculosis and leprosy. The currently recommended combination of rifampicin-streptomycin suffers from side effects and poor compliance, which leads to reliance on local herbal remedies. The objective of this study was to investigate the antimycobacterial properties and toxicity of selected medicinal plants. Sixty-five extracts from 27 plant species were screened against Mycobacterium ulcerans and Mycobacterium smegmatis, using the Resazurin Microtiter Assay (REMA). The cytotoxicity of promising extracts was assayed on normal Chang liver cells by an MTT assay. Twenty five extracts showed activity with minimal inhibitory concentration (MIC) values ranging from 16 µg/mL to 250 µg/mL against M. smegmatis, while 17 showed activity against M. ulcerans with MIC values ranging from 125 µg/mL to 250 µg/mL. In most of the cases, plant extracts with antimycobacterial activity showed no cytotoxicity on normal human liver cells. Exception were Carica papaya, Cleistopholis patens, and Polyalthia suaveolens with 50% cell cytotoxic concentrations (CC50) ranging from 3.8 to 223 µg/mL. These preliminary results support the use of some West African plants in the treatment of Buruli ulcer. Meanwhile, further studies are required to isolate and characterize the active ingredients in the extracts.

In vitro immunomodulatory activity, cytotoxicity and chemistry of some central European polypores

Context Some mushrooms of the order Polyporales are known for their immunomodulatory actions.Objective The objective of this study is to evaluate the in vitro phagocytic and cytotoxic effects of extracts from polyporales native to Central Europe.Materials and methods The effects of ethanol extracts from 27 polypore species on opsonized zymosan-induced phagocytosis of isolated human neutrophils were tested by a chemiluminescence method. Colon epithelial cell lines, Caco-2 and HT-29, were used for cytotoxicity assays, and extracts were chemically characterized in terms of total phenolic and β-glucan content.Results We observed phagocytosis or respiratory burst enhancing activity in 17 extracts, of which five species, namely Aurantiporus fissilis (Berk. & M.A. Curtis) H. Jahn ex Ryvarden, Trametes gibbosa (Pers.) Fr., Piptoporus betulinus (Bull.) P. Karst, Neolentinus lepideus (Fr.) Redhead & Ginns, Polyporus squamosus (Huds.) Fr., significantly increased phagocytosis in granulocytes by 205, 181, 158, 155 and 141%, respectively. The β-glucan content of the three most potent extracts was 58, 42 and 74 mg/g, respectively, and the polyphenol content was 155.6, 133.5 and 155.2 μmol of gallic acid equivalent/g, respectively. Some extracts showed cytotoxic activity, with higher cytotoxicity in Caco-2 than in HT-29 cells. Pycnoporus cinnabarinus (Jacq.) P. Karst. extract was cytotoxic to both cell lines, with IC50 values of 81 and 31 μg/mL, respectively.Discussion and conclusion The most promising extracts were from N. lepideus and Polyporus squamosus, which are edible species and may be considered safe. Our findings support their use as culinary preparations or food supplements for various immunological gut disorders.

Taraxacum officinale dandelion extracts efficiently inhibited the breast cancer stem cell proliferation

Background: Breast cancer stem cells (BCSCs) play an important role in breast cancer initiation, metastasis, recurrence, and drug resistance. Therefore, targeting BCSCs is an essential strategy to suppress cancer growth. This study aimed to evaluate the effects of dandelion Taraxacum officinale extracts on BCSC proliferation in vitro in 2D and 3D cell culture platforms. Materials and Methods: The BCSCs were maintained under standard conditions, verified for expression of CD44 and CD24 surface markers, and transfected with GFP before use in experiments. In the 2D model, the BCSCs were cultured as adherent cells in standard culture plates; in the 3D model, the BCSCs were cultured on low-adherent plates to form spheroids. The effect of Dandelion extracts on proliferation of BCSC was assessed by evaluating induction of cell death, expression of genes of death receptor signaling pathways, and production of reactive oxygen species (ROS) by BCSCs. Results: BCSCs formed spheroids as microtumors in vitro and exhibited some in vivo characteristics of tumors, such as increased expression of N-cadherin and Slug, decreased expression of E-cadherin, capacity to invade into the extracellular matrix (ECM), and presence of a hypoxic environment at the core of tumor spheroids. The dandelion extracts significantly inhibited BCSC proliferation in both two-dimensional (2D) and three-dimensional (3D) models of BCSCs. However, the IC50 value of dandelion extracts in BCSCs in the 3D model was much higher than that in the 2D model. The results also demonstrated that BCSCs treated with Dandelion extracts showed increased expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TRAIL receptor 2 (TRAILR2; i.e. death receptor 5; DR5). Moreover, treatment induced expression of DR4. Treatment with methanol dandelion extract enhanced production of ROS in BCSCs. Conclusion: Dandelion extracts are promising extracts for the treatment of breast tumors. The effect of methanol extract (with dandelion extract) was better than that for ethanol extract. Importantly, BCSCs in 3D exhibited stronger drug resistance than those in 2D. In summary, our results indicate the strong potential of dandelion extracts as anti-cancer agents and rational use for drug development.