Activity Of Plant Extracts Research Articles

Comparison of Antibacterial activity and medicinal properties of ginger (Zingiber officinale) and garlic (Allium sativum) between native and international genera

Human societies have always a golden sign to show the noticeable spectacles of coexistence with their environments, precisely the impact of plants in every phases of their life. Several qualitative as well as quantitative approaches are taken into account to emphasize the effective integration of plants into a medical system. Therefore this experiment was designed to standardize and evaluate the health of active plant-extract and their dynamic use in healthcare system to open a new era in drug designing. In order to maintain this knowledge, plant extract of ginger and garlic from native and hybrid source were chosen (July 2018 to July 2019 from different zone of Bangladesh) in this experiment and sensitivity pattern of these extracts against two enteric disease causing organisms Bacillus cereus and Vibrio cholerae were conducted to investigate the role of these natural sources as medicinal plants. To compare the authenticity and efficacy of the plant extracts, selected strains were also challenged with conventional antibiotics. Finally, the results portrayed that the ethanoic and methanoic extract of both native garlic and ginger extracts showed more prominent sensitivity towards the gram negative organisms as compared to the foreign plants of same genera.

Evaluation of antimitotic activity of herbal extracts using plant-based model systems and their cytotoxic potential against human colon carcinoma cells.

The aim of this study was to screen plant extracts for antimitotic activity using Vigna radiata germination inhibition assay, followed by Allium cepa root tip assay and evaluation of their cytotoxic potential on colon carcinoma (HCT-116) cell lines. Aqueous extracts of Aconitum heterophyllum, Terminalia bellirica, Bauhinia variegata, Vanda roxburghii, and Cassia angustifolia were prepared by maceration method, and preliminary screening studies to check their antimitotic activity were done by V. radiata germination inhibition assay, followed by A. cepa root tip assay. Furthermore, cytotoxic actions were evaluated by cell proliferation assay. Effect of T. bellirica aqueous extract was analyzed to induce morphological changes, cell death, lactate dehydrogenase release, and cell survival of HCT-116 cells. The data represented were analyzed by Student's t-test using SigmaStat 2.0 statistical analysis software. The normality of data was tested by the Shapiro-Wilk test before the Student's t-test. P values *P ≤ 0.05, **P ≤ 0.01, and ***P ≤ 0.001 were considered as statistically significant. All the plant extracts showed promising antimitotic activity. Out of all, T. bellirica was highly effective on HCT-116 cells and promising effect on cell proliferation assay and Annexin-propidium iodide staining revealed that T. bellirica efficiently induces apoptosis. T. bellirica inhibits cancer cell growth and induces apoptotic cell death. Collectively, it may hold potential for cancer therapeutics.

Phagocytosis, Degranulation and Extracellular Traps Release by Neutrophils-The Current Knowledge, Pharmacological Modulation and Future Prospects.

Neutrophils are crucial elements of innate immune system, which assure host defense via a range of effector functions, such as phagocytosis, degranulation, and NET formation. The latest literature clearly indicates that modulation of effector functions of neutrophils may affect the treatment efficacy. Pharmacological modulation may affect molecular mechanisms activating or suppressing phagocytosis, degranulation or NET formation. In this review, we describe the role of neutrophils in physiology and in the course of bacterial and viral infections, illustrating the versatility and plasticity of those cells. This review also focus on the action of plant extracts, plant-derived compounds and synthetic drugs on effector functions of neutrophils. These recent advances in the knowledge can help to devise novel therapeutic approaches via pharmacological modulation of the described processes.

REVIEW ON ANTIMICROBIAL AND ANTI ACNE POTENTIAL OF KAEMPFERIA SPP.

Acne is a general but somber skin disease, which affects approximately 80% adolescents and young adults in 11–30 age groups. 42.5 % of men and 50.9 % of women keep onto suffer from this disease into their twenties. Bacterial resistance is now at the alarming stage due to the irrational use of antibiotics. Hence, search for new lead molecule/bioactive and rational delivery of the existing drug (for better therapeutic effect) to the site of action is the need of the hour. Plants and plant-derived products have been an integral part of health care system since time immemorial. Therefore, plants that are currently used for the treatment of acne and those with a high potential are summarized in the present review. Most active plant extracts, namely, P. granatum, M. alba, A. anomala, and M. aquifolium exhibit minimum inhibitory concentration (MIC) in the range of 4–50 µg/mL against P. acnes, while aromatic oils of C. obovoides, C. natsudaidai, C. japonica, and C. nardus possess MICs 0.005–0.6 ?L/mL and phytomolecules such as rhodomyrtone, pulsaquinone, hydropulsaquinone, honokiol, magnolol, xanthohumollupulones, chebulagic acid and rhinacanthin-C show MIC in the range of 0.5–12.5 ?g/mL. Novel drug delivery tant plant leads in the treatment of acne have also been discussed.

Efficacy of Cuscuta campestris Yunck. (Solanales: Convolvulaceae) and Lupinus albus L. (Fabales: Fabaceae) crude extracts against nymphs and adults of Orosanga japonica (Melichar, 1898) (Hemiptera: Ricaniidae)

The planthopper, Orosanga japonica (Melichar, 1898) (Hemiptera: Ricaniidae), is an important agricultural pest of grapevine, kiwifruit and tea in Asia and in some countries of Eastern Europe. The efficacy of the crude extracts of Cuscuta campestris Yunck. (Solanales: Convolvulaceae) and Lupinus albus L. (Fabales: Fabaceae) plants was evaluated under laboratory conditions for control of O. japonica nymphs and adults collected in 2019 from Rize (Turkey). Their toxic efficacies were investigated by two different methods. Fixed-dose death rates were used for LT50 calculation and dosage test results were used for LC50 calculation. Also, the phenolic constituents of active plant extracts were examined using HPLC-DAD. Generally, the LT50 values obtained using ethyl acetate extracts were lower than those with methanol extracts. LT50 values of adults were found lower than in nymphs. The test plants crude extracts had high activity at and below 2 g/L (LC90) for two different plants. HPLC-DAD results showed that the high concentration of kaempferol and quercetin for each extract. Extracts of both plants gave promising results for use in O. japonica control, but more detailed studies on the active constituents of these candidate plants need to be undertaken.

Use of plant-derived drugs in the prevention and treatment of dairy cow mastitis

Dairy cow mastitis is one of most seriously diseases affecting dairy herds. The prevention and treatment of this pathology is especially done through antimicrobials, but the increasing antimicrobial resistance of pathogens to this disease may affect the efficiency of conventional drugs. Plant extracts are increasingly being valued by livestock producers because of their wide sources, low toxic and side effects, and high environmental affinity. Thereby, a lot of research has been conducted on the control of dairy cow mastitis by plant-derived drugs in recent years. This review summarizes the current of the plant types, main active ingredients, and the mechanism of action of plant extracts for preventing and treating dairy cow mastitis. Finally, a review was carried out to prospect the future development of plant extracts in the treatment of dairy cow mastitis.

Natural Antioxidants in Anemia Treatment.

Anemia, characterized by a decrease of the hemoglobin level in the blood and a reduction in carrying capacity of oxygen, is a major public health problem which affects people of all ages. The methods used to treat anemia are blood transfusion and oral administration of iron-based supplements, but these treatments are associated with a number of side effects, such as nausea, vomiting, constipation, and stomach pain, which limit its long-term use. In addition, oral iron supplements are poorly absorbed in the intestinal tract, due to overexpression of hepcidin, a peptide hormone that plays a central role in iron homeostasis. In this review, we conducted an analysis of the literature on biologically active compounds and plant extracts used in the treatment of various types of anemia. The purpose of this review is to provide up-to-date information on the use of these compounds and plant extracts, in order to explore their therapeutic potential. The advantage of using them is that they are available from natural resources and can be used as main, alternative, or adjuvant therapies in many diseases, such as various types of anemia.

Effects of 22 traditional anti-diabetic medicinal plants on DPP-IV enzyme activity and glucose homeostasis in high-fat fed obese diabetic rats

The present study investigated the effects of hot water extracts of 22 medicinal plants used traditionally to treat diabetes on Dipeptidyl peptidase-IV (DPP-IV) activity both in vitro and in vivo in high-fat fed (HFF) obese-diabetic rats. Fluorometric assay was employed to determine the DPP-IV activity. For in vivo studies, HFF obese-diabetic rats were fasted for 6 h and blood was sampled at different times before and after the oral administration of the glucose alone (18 mmol/kg body weight) or with either of the four most active plant extracts (250 mg/5 ml/kg, body weight) or established DPP-IV inhibitors (10 μmol/5 ml/kg). DPP-IV inhibitors: sitagliptin, vildagliptin and diprotin A, decreased enzyme activity by a maximum of 95–99% (P<0.001). Among the 22 natural anti-diabetic plants tested, Anogeissus Latifolia exhibited the most significant (P<0.001) inhibitory activity (96 ± 1%) with IC50 and IC25 values of 754 and 590 μg/ml. Maximum inhibitory effects of other extracts: Aegle marmelos, Mangifera indica, Chloropsis cochinchinensis, Trigonella foenum-graecum and Azadirachta indica were (44 ±7%; 38 ± 4%; 31±1%; 28±2%; 27±2%, respectively). A maximum of 45% inhibition was observed with >25 μM concentrations of selected phytochemicals (rutin). A. latifolia, A. marmelos, T. foenum-graecum and M. indica extracts improved glucose tolerance, insulin release, reduced DPP-IV activity and increased circulating active GLP-1 in HFF obese-diabetic rats (P<0.05–0.001). These results suggest that ingestion of selected natural anti-diabetic plants, in particular A. latifolia, A. marmelos, T. foenum-graecum and M. indica can substantially inhibit DPP-IV and improve glucose homeostasis, thereby providing a useful therapeutic approach for the treatment of T2DM.

Is AMF inoculation an alternative to maximize the in vitro antibacterial activity of Libidibia ferrea extracts?

Arbuscular mycorrhizal fungi (AMF) are known to provide plant species with several benefits, such as an increased production of bioactive compounds. However, it is yet to be defined whether extracts of mycorrhizal plants are more efficient in vitro antibacterial actions when compared to non-mycorrhizal plants. We tested the hypothesis of whether or not, methanolic extracts of Libidibia ferrea fruits, from plants established in the field and inoculated with AMF, have higher antibacterial action when inoculated with Acaulospora longula, Claroideoglomus etunicatum or Gigaspora albida. In addition, native L. ferrea fruits collected from the Caatinga area were also tested. The extracts of L. ferrea fruits inoculated with A. longula had higher in vitro antibacterial action in relation to the extracts of fruits from non-inoculated plants (p &lt;0.05) thus characterizing the first record of different antibacterial actions of plant extracts due to inoculation with AMF. The extracts of L. ferrea fruits inoculated with A. longula were more efficient in inhibiting growth of Gram-negative bacteria. The zone diameters of inhibition ranged from 2.48 % to 7.56 % larger than the zones of the non-inoculated L. ferrea fruit extracts. The inoculation of L. ferrea with AMF may represent an alternative way of producing fruits with different antibacterial activity.

In vitro antibacterial and antibiotic-potentiation activities of five edible plant extracts and mode of action against several MDR Gram-negative phenotypes

Abstract Background: Bacterial infections involving the multidrug resistant (MDR) strains are among the top leading causes of death throughout the world. Healthcare system across the globe has been suffering from an extra-ordinary burden in terms of looking for the new and more potent antimicrobial compounds. The aim of the present study was to determine the antibacterial activity of some Cameroonian edible plants (Garcinia lucida bark, Phoenix dactylifera pericarps, Theobroma cacao pod, Solanum macrocarpon leaves and Termitomyces titanicus whole plant) and their antibiotics-potentiation effects against some MDR Gram-negative bacteria phenotypes expressing efflux pumps (Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae, Pseudomonas aeruginosa and Providencia stuartii strains). Methods: The antibacterial activities of plant extract alone and in combination with usual antibiotics were carried out using the micro-dilution method. The effects of the most active plant extract (Garcinia lucida bark) on H+-ATPase-mediated proton pumps and on bacterial growth kinetic were performed using experimental protocols, while qualitative reference methods were used to highligh the major groups of secondary metabolites present in the extracts. Results: Qualitative phytochemical screening of plant extracts indicated that all analysed secondary metabolites were present in Theobroma cacao and Termitomyces titanicus while one (saponins) of them was absent in Garcinia lucida and Solanum macrocarpon. Only three of them (polyphenols, flavonoids and saponins) were detected in Phoenix dactylifera. Antibacterial essays showed that G. lucida was the most active plant as it inhibited the growth of all studied bacteria with strong activity (MIC&lt;100 µg/mL) against E. coli ATCC8739, significant activity (100≤MIC≤512 µg/mL) against 80% of bacteria and moderate activity (512&lt;MIC≤2048 µg/mL) against E. coli AG100A and E. aerogenes (EA289 and CM64). It was followed by T. cacao and S. macrocarpon extracts which exhibited an antibacterial potential against 95% and 80% of bacterial strains, respectively. These three extracts exhibited a bactericidal effect on a few bacteria. Extracts from T. titanicus and P. dactylifera were less active as they moderately (512&lt;MIC≤2048 µg/mL) inhibited the growth of 35% and 10% of bacteria. All extracts selectively potentiated the activities of all antibiotics with improvement activity factors (IAF) ranging from 2 to 256. G. lucida, T. cacao and S. macrocarpon potentiated the activities of 100%, 89% and 67% of antibiotics respectively against more than 70%, suggesting that they contain bioactive compounds which could be considered as efflux pumps inhibitors. Whereas T. titanicus and P. dactylifera improved the activities of almost 40% and 20% of antibiotics, respectively. This increase of activities also characterizes synergistic effects between antibiotics and these bioactive compounds. G. lucida extract at all tested concentrations, strongly inhibited the growth of bacterial strain E. coli ATCC8739 and exhibited an inhibitory effect on this bacterial H+-ATPase-mediated proton pumps increasing the pH of the medium. Conclusion: The overall results indicated that food plants among which G. lucida, T. cacao and S. macrocarpon could have a benefit interest in combatting resistant types of bacteria. Keywords: Food plants; infectious diseases; MDR bacteria; efflux pumps; antibiotics; secondary metabolites.

A comparative evaluation of Juniperus species with antimicrobial magistrals.

The objective of this study was to evaluate the in vitro bioactivity of the active ingredient in selected antimicrobial magistral drug formulations and plant extracts used in folk medicine, comparatively. The active ingredients of magistrals such as; boric acid, balsam of Peru, zinc oxide, Calendula tincture, thymol, resorcinol, crystal violet were used as well as fruit or leaf extracts of Juniperus excelsa (Je), J. sabina (Js), J. foetidissima (Jf), J. communis ssp. nana (Jcsn), and J. oxycedrus spp. oxycedrus ripe (Joso) to determine the antimicrobial activity against gram positive bacteria (S. pyogenes, S. aureus, S. epidermidis, E. faecalis), gram negative bacteria (K. pneumoniae, H. influenza, P. aeruginosa, A. baumannii, E. coli), and fungi (Candida. albicans, C. tropicalis, C. parapsilosis, C. krusei) by using microdilution method. The inhibition end point of the minimum inhibition concentrations (MICs) were determined as μ mL-1. The active ingredient and plant extracts have shown antibacterial and antifungal activities with a MIC values of 1-&gt;128μmL-1. The active ingredient crystal violet (MIC; 1 μ mL-1) as well as Je- fruit ethanol, Jf-leaf and fruit ethanol, Joso-leaf and fruit ethanol extracts (MIC; 16μ mL-1) have exhibited the highest antimicrobial activities (MIC; 16μ mL-1). Although ingredients of magistrals seem to exert similar antifungal activity against C. albicans, C. tropicalis, and C. parapsilosis (MIC; 32μmL-1), thymol and resorcinol were observed to be more active against C. krusei (MIC; 16μ mL-1). Extracts were more pronounced against P. aeruginosa, A. baumannii, and S. epidermidis (MIC ranging from 16 to 32). In the mine time, the extracts showed equal antifungal activity against C. albicans and C. parapsilosis (MIC; 16μ mL-1). In our study, antimicrobial activity of the natural compounds and ingredients of selected magistrals have found to be promising with MIC values of 16-32μ mL-1. According to the results of our antimicrobial activity studies, utilization of Juniperus extracts in antimicrobial magistral formulations can be suggested.

Assessment of in vitro and in vivo antimalarial efficacy and GC-fingerprints of selected medicinal plant extracts

A hallmark of mortality and morbidity, malaria is affecting nearly half of the world's population. Emergence of drug-resistant strains of malarial parasite prompts identification and evaluation of medicinal plants and their constituents that may hold the key to a new and effective anti-malarial drug. In this context, nineteen methanolic extracts from seventeen medicinal plants were evaluated for anti-plasmodial potential against Plasmodium falciparum strain 3D7 (Chloroquine (CQ) sensitive) and INDO (CQ resistant) using fluorescence based SYBR-Green assay and for cytotoxic effects against mammalian cell lines. Leaf extract of two plants showed promising in vitro anti-malarial activity (Pf3D7 IC50 ≤ 10 μg/ml); one plant extract showed good activity (Pf3D7 IC50 = 10.1–20 μg/ml); seven were moderately active (IC50 = 20.1–50 μg/ml), four plant extracts showed poor activity (PfD7 IC50 = 50.1–100 μg/ml) and five extracts showed no activity up to IC50 = 100 μg/ml. Further, six extracts were found equipotent to PfINDO (resistance index ranging 0.4–2) and relatively nontoxic to mammalian cell lines HEK293 (cytotoxicity index ranging 1.4–12.5). Based on good resistance and selectivity indices, three extracts were evaluated for in vivo activity in Plasmodium berghei ANKA infected mice at a dose of 500 mg/kg and they showed significant suppression of P. berghei parasitemia. Further, these active plant extracts were fractionated using silica-gel chromatography and their fractions were evaluated for anti-plasmodial action. Obtained fractions showed enrichment in antimalarial activity. Active fractions were analyzed by gas chromatography and mass-spectrometery. Results suggests that the three active plant extracts could serve as potent source of anti-malarial agent and therefore require further analysis.

Antimicrobial activity of mono- and polynuclear platinum and palladium complexes

Introduction. Infectious diseases remain a serious threat to humanity worldwide as bacterial pathogens grow more diverse. Bacteria, fungi, and parasites develop resistance to clinically approved antimicrobials, which reduces the efficacy of available drugs and treatment measures. As a result, there is an ever growing demand for new highly effective pharmaceuticals. This review describes mono- and polynuclear platinum and palladium complexes with antimicrobial properties. We compared several groups of antibacterial agents: antibiotics, antioxidant biologically active substances, antimicrobial nanoparticles, nanocomposite materials, biopolymers, micellar systems, and plant extracts.&#x0D; Study objects and methods. The review covered relevant articles published in Web of Science, Scopus, and Russian Science Citation Index for the last decade. The list of descriptors included such terms as mononuclear and binuclear complexes of platinum, palladium, and antimicrobial activity.&#x0D; Results and discussion. Chelates of platinum, palladium, silver, iridium, rhodium, ruthenium, cobalt, and nickel are popular therapeutic agents. Their antimicrobial activity against pathogenic microorganisms can be enhanced by increasing their bioavailability. Metalbased drugs facilitate the transport of organic ligands towards the bacterial cell. The nature of the ligand and its coordination change the thermodynamic stability, kinetic lability, and lipophilic properties of the complex, as well as the reactivity of the central atom. Polynuclear platinum and palladium complexes contain two or more bound metal (coordinate) centers. Covalent bonding with bacterial DNA enables them to form a type of DNA adducts, which is completely different from that of mononuclear complexes.&#x0D; Conclusion. Metal-based drugs with functional monodentate ligands exhibit a greater antimicrobial effect compared to free ligands. Poly- and heteronuclear complexes can increase the number of active centers that block the action of bacterial cells. When combined with other antibacterial agents, they provide a synergistic effect, which makes them a promising subject of further research.

PHYTOCHEMICAL AND BIOLOGICAL STUDIES ON SOME MEDICINAL PLANTS

Biological studies on thirteen ethanolic plant extracts (Rosmarinus officinalis ,Ocimum basilicum , Moringa oleifera, Zingiber officinale, Curcuma longa, Nigella sativa ,Cinnamomum verum ,Salvia officinalis, Lepidium sativum, Foeniculum vulgare, Anethum graveolens, Ficus benghalensis and Cinnamomum camphora )revealed that four of them (Rosmarinus officinalis , Zingiber officinale, Cinnamomum verum and Cinnamomum camphora) were the best active against two bacterial species ; E. coli , S .aureus and one fungus species C. albicans. Also, their synergistic effects against E. coli, S. aureus and C. albicans were studied .So, the phytochemical studies were completed on these four plants . This study aimed to evaluate the chemical composition of the best active plant extracts. The chemical major content of Rosmarinus officinalis was eucalyptol (7.48%) , Zingiber officinale was gingerol (12.73%) , Cinnamomum verum was (E)- cinnamaldehyde (25.55 % ) and Cinnamomum camphora was eugenol ( 27 .35% ) . The minimum inhibitory concentration (MIC) values varied from 0.625 to 2.5 mg/ml, for the S. aureus (gram positive bacteria) affected by Rosmarinus officinali, Zingiber officinale, Cinnamomum verum and Cinnamomum camphora. Respectively. C. albicans was the most effective microorganism by Cinnamomum verum and the least effective microorganism by Rosmarinus officinalis and Cinnamomum camphora. ethanolic extracts, as MIC ranged from 0.15 to 1.25 mg/ml.

BIOLOGICAL ACTIVITIES OF SOME SELECTED NEPALESE MEDICINAL PLANTS AND ISOLATION OF CHEMICAL CONSTITUENTS FROM CALLICARPA MACROPHYLLA

Objective: The main objectives of this study was to analyze the phytochemicals, determine the total flavonoid content, brine shrimp toxicity, antibacterial activity, evaluate the antioxidant, antimicrobial, anti-diabetic activities of nine medicinal plants Callicarpamacrophylla, Bauhinia purpurea, Plumeriarubra, Girardiniadiversifolia, Acacia nilotica, Woodfordiafruticosa (Bark) Woodfordiafruticosa (flower), Terminaliaalata, and Premnabarbata. &#x0D; Methods: The cold percolation method was adopted for the extraction of secondary metabolites in methanol. The preliminary phytochemical analysis was performed by colour differentiation methods. The radical scavenging activity was evaluated by DPPH (2,2-diphenyl-1-picrylhydrazyl) method. The antidiabetic activity was performed by α-amylase enzyme inhibition activity. The chemical constituent was isolated by column chromatography from the biologically active plant fraction.&#x0D; Results: The phytochemical investigation has shown plants are the rich source of secondary metabolites as quinones, saponins, terpenoids and glycosides. Among the nine tested plants, Terminaliaatalia showed the highest radical scavenging activity 96.41±0.47 with IC50 value 6.353 µg/ml, followed by Girardiniadiversifolia 97.26±0.67 with IC50 value 11.52 µg/ml whereas ascorbic acid has 39.85 µg/ml as standard. Bauhinia purpurea showed significant inhibition to the α-amylase enzyme having inhibitory concentration IC50 17.05±13.00 SD in a dose-dependent manner. Woodfordiafruticosa demonstrated significant toxicity to A. salina with LC50 value of 457.08 µg/ml. Callicarpamacrophylla bark showed a potential inhibitory activity against the growth of Straphylococcusaureus as compared to standard chloramphenicol. Active plant extract of Callicarpamacrophylla was subjected for column chromatography. Conclusion: Out of nine plant samples Terminaliaatalia showed the highest radical scavenging activity. The plant extract of Bauhinia purpurea showed significant inhibition to the α-amylase enzyme inhibition. Woodfordiafruticosa demonstrated significant toxicity to A. salina, whereas Callicarpamacrophylla showed the potent antibacterial activity. The active plant extract was subjected for column chromatography and different fractions were collected in solvent polarity basis.&#x0D; Conclusion: The phytochemical investigations showed that plant extracts are the rich sources of secondary metabolites such as alkaloids, flavonoids, saponins, glycosides, polyphenols, coumarins and reducing sugars which showed they are supposed to be responsible for different biological activities. IC50 values showed the varied degree of antioxidant property of which Plumeriarubra and Acacia nilotica exhibit good antioxidant property with IC50 value close to the standard ascorbic acid.

Dynamic profiles of fermentation characteristics and bacterial community composition of Broussonetia papyrifera ensiled with perennial ryegrass

Broussonetia papyrifera (B. papyrifera) has been proposed to improve silage fermentation due to its high content of protein and abundant active plant extracts. Thus, dynamic profiles of fermentation quality and bacterial community of B. papyrifera mixing with perennial ryegrass in different ratios: 100:0, 90:10, 80:20, 70:30, 60:40, and 50:50 were examined during 60-d fermentation. Results showed that adding perennial ryegrass increased soluble carbohydrate content and lactic acid production in silage and decreased pH and population of epiphytic microorganisms. Adding ryegrass exerted a remarkable effect on the silage bacterial community with a dramatic decrease in the abundance of Enterobacter. Spearman’s rank correlation showed that silage lactic acid concentration was positively correlated with Lactobacillus and Stenotrophomonas abundance, while ammonia nitrogen concentration was positively correlated with the abundance of Enterobacter. In conclusion, B. papyrifera ensiled with perennial ryegrass could improve B. papyrifera silage quality and provide high-quality forage resources for sustainable ruminant livestock production.

Combating antibiotic resistance using plant‐derived compounds

Bacteria have steadily developed defenses against antibiotics since the world’s first fleet of antibacterial drugs was introduced. One strategy that bacteria can use to become multi‐drug resistant involves the overexpression of large, membrane‐embedded efflux pumps, such as the AcrAB‐TolC pump found in Escherichia coli (E. coli) and other Gram‐negative bacteria. This large efflux pump gives the bacterium the capability of transporting a wide variety of compounds out of the cell, including antibiotics that we use to combat bacterial infections. Overexpression of efflux pumps has been shown to lead to multidrug resistance in clinically important bacterial pathogens. Here, I have sought to identify novel inhibitors of bacterial efflux pumps by screening methanolic plant extracts for efflux pump inhibitory activity using an ethidium bromide‐based fluorescence assay. I have determined that yerba maté extract causes accumulation of ethidium bromide in live E. coli bacterial cells. To determine the ability of yerba maté extract to cause accumulation of clinically relevant antibiotics, I used growth curve analysis of E. coli in the presence of the plant extract with levofloxacin and carbenicillin. I have concluded that the combination of yerba maté and antibiotics enhances the susceptibility of bacteria. This research could open up a new avenue in the treatment of multi‐drug resistant bacterial infections.Support or Funding InformationClare Boothe Luce Research Scholars Program

Combination effect of three anti-HSV-2 active plant extracts exhibiting different modes of action

The emergence of multidrug-resistant viruses leads to discover a novel source of drugs or a new strategy to overcome this obstacle. Combined herbal therapies are becoming a promising approach for a better efficiency. In this study, Pistacia lentiscus and Peganum harmala were investigated for their anti HSV-2 activity. Twenty eight organic extracts from different organs were evaluated for their cytotoxicity on Vero cells and their anti HSV-2 activity using the MTT test and the plaque reduction assay, respectively. Peganum harmala methanol seeds extract, Pistacia lentiscus methanol stem and dichloromethane fruit extracts were active on HSV-2 with selectivity index values of 13.19, 51.23 and 10.23, respectively. These active extracts exhibited different mode of action: (1) Peganum harmala methanol seeds extract showed a virucidal action before virus adsorption and penetration, and on the newly formed virions before their release outside infected cells—(2) Pistacia lentiscus methanol stem extract exhibited virucidal effect only before virus adsorption and penetration—(3) Pistacia lentiscus dichloromethane fruit extracts demonstrated virus inhibition up to 7 h post infection. The binary combination of the three active extracts did not improve their individually activity. This report could contribute to prove that combination of active extracts do not necessary increase the initial activity.

Polymeric nanoparticles containing Tithonia diversifolia (hemsl) a. Gray flowers alcoholic extract and coated by hyaluronic acid_ development, synthesis, and characterization

Nanoparticles are systems formed by biodegradable, synthetic or natural polymers, that have gained significant importance in different industry segments, as well as being the highlight of essential researches. These tiny particles present various promising characteristics, such as: site-specific and gradual drug release and improvement of active principle solubility and stability. The combination of nanotechnology with medicinal plants could be able to enhance the action of plant extracts, such so that many innovative drug carriers have emerged, including polymeric nanoparticles. The objective of this study was to synthesize and characterize polymeric nanoparticles coated with hyaluronic acid, containing Tithonia diversifolia (Hemsl) A. Gray flowers alcoholic extract, aiming to improve the nanoparticle’s stability, for possible future applications. The synthesis occurred through emulsion polymerization, where the monomer n-butyl-cyanoacrylate was incorporated with Dextran® into an aqueous HCl solution, with posterior addition of the alcoholic plant extract and neutralization reaction with NaOH. Stability parameters, such as hydrodynamic diameter, polydispersity index, zeta potential, spectroscopy (IV), Scanning Electron Microscopy (SEM), thermogravimetry (TG) and Differential Exploration Calorimetry (DSC) were analysed. The nanoparticle system was evaluated taking into consideration particle stability prior and posterior to the addition of the extract, as well as coated and uncoated particles. The results demonstrated the good reactivity of the monomers of cyanoacrylates, as well as effectiveness of hyaluronic acid in relation to the proposed objective, evidenced in the results obtained by Infrared Spectroscopy, by SEM, DSC and, also, TG. The study demonstrated that there are possible future applications for this method.

Antioxidant and Antimicrobial Studies of Some Hemi-parasitic West African Plants

The study investigated the antioxidant and antimicrobial activities of some West African hemi-parasitic plants, which comprised Tapinanthus bangwensis (TB), Tapinanthus globiferus (TG) and Globimetula braunii (GB), used in Nigerian ethnomedicine for the management of skin and other microbial infections. This was with a view to determining the most active plant extract and fraction. The leaf and stem of each plant was separately air-dried, powdered and macerated in ethanol-H20 (8:2). The extracts were subjected to in vitro antioxidant tests such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), Fe2+ chelating ability (FIC) and total antioxidant capacity (TAC) assays, with L-ascorbic acid, quercetin and ethylenediaminetetraacetic acid (EDTA) as positive controls. The antimicrobial test was carried out using micro-broth dilution method against reference strains of methicillin-resistant Staphylococcus aureus (MRSA), Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans, where ciprofloxacin and ketoconazole were the positive controls. An activity-guided fractionation approach was adopted in the study. The most active GB leaf extract was fractionated to obtain n-hexane, dichloromethane, ethylacetate, n-butanol and aqueous fractions, and were subsequently tested. The results showed that the extract of GB leaf demonstrated the highest bioactivities with inhibitory concentration (IC50) of DPPH at 31.21±1.11 µg/mL, FRAP value of 109.30±0.76 mg AAE/g, TAC value of 178.15±3.54 mg AAE/g and MIC of 5.0 – 10.0 mg/mL. The Ethylacetate fraction of GB leaf demonstrated the highest bioactivities, which were four-times, thrice and twice better than its GB leaf extract in the DPPH, TAC and antimicrobial studies respectively. The EtOAc fraction (IC50 = 8.58±1.39 µg/mL) was comparable (P &gt; 0.05) in antioxidant activity with quercetin (IC50 = 7.72±0.88 µg/mL). The EtOAc fraction also exhibited broad-spectrum antimicrobial activity with inhibitory concentration of 1.25 mg/mL against MRSA and C. albicans. In conclusion, the extract of G. braunii leaf demonstrated considerable bioactivities and the moderately polar EtOAc fraction was the most active fraction; hence, validates the folkloric use G. braunii leaf as a remedy for microbial infections.