Increasing Extract Concentration Research Articles

Azardirachta Indica Leaves Ark’s as Green Corrosion Inhibitor for Aluminum in HCl Solutions

The purpose of this paper to find out the effect of Azardirachta indica (Neem) leaves ark’s on the corrosion of aluminum in 0.4, 0.5 and 0.6M hydrochloric acid (HCl), and elucidates the mechanism of the inhibition system. Gravimetric and galvanostatic polarization methods were used to investigate the effect of aluminum corrosion in HCl solutions. The outcome revealed that maximum inhibitor efficiency which corresponds to the lowest corrosion rate was obtained at most favorable inhibitor concentration of 1.25% with reduction in the corrosion rate observed to follow in order of increasing extract concentration. The adsorption study promote that Langmuir isotherm best described the metal surface interaction with the Azardirachta indica (Neem) leaves ark’s with the best exposure time for the Azardirachta indica (Neem) leaves ark’s to adsorb to the metal surface at all concentrations. Polarization study reveals that the inhibitors functions as a mixed inhibitor.

Biocorrosion inhibition of mild steel in crude oil-water environment using extracts of Musa paradisiaca peels, Moringa oleifera leaves, and Carica papaya peels as biocidal-green inhibitors: kinetics and adsorption studies

Biocorrosion inhibition of mild steel in the crude oil-water environment was investigated in the absence and presence of Carica papaya peel extract, Musa paradisiaca peel extract, and Moringa oleifera leaf extract as potential biocidal-green inhibitors using gravimetric, polarization, and surface analysis (Inverted metallurgical microscope and Fourier transform infra-red spectroscopy) methods. Kinetics and adsorption behaviors of the extracts were determined and evaluated. Results revealed that each of the extracts functioned as biocidal-green inhibitors in the crude oil-water environment and that biocorrosion inhibition efficiency (IE%) of each extract increased with increase in extract concentration and exposure time. Maximum IE% of 97.7, 96.5, and 99.2% was achieved with Musa paradisiaca peel extract, Moringa oleifera leaf extract, and Carica papaya peel extract, respectively, at 4000 mg/l extract concentration and 35 d exposure time. Polarization studies indicated that each of the extracts acts as a mixed-type inhibitor. Mild steel susceptibility to biocorrosion was significantly reduced by each of the extracts through biofilm development suppression and extract adsorption onto the mild steel surface which obeyed Langmuir, Freundlich, Temkin, and Flory-Huggins isotherm models. Kinetics of mild steel biocorrosion inhibition followed a Monod form of kinetics (Type A). Gibbs free energy of adsorption values for Musa paradisiaca peel extract (−9.65 kJ/mol), Moringa oleifera leaf extract (−9.57 kJ/mol), and Carica papaya peel extract (−9.71 kJ/mol) showed that each extract adsorption was spontaneous and of physical adsorption.

IN VITRO STUDY OF ANTITRYPANOSOMAL ACTIVITY OF ETHANOLIC LEAF EXTRACT OF GARCINIA KOLA AGAINST TRYPANOSOMA BRUCEI BRUCEI

Objective: The study was aimed at evaluating in vitro antitrypanosomal activity of Garcinia kola against Trypanosoma brucei brucei.Methods: The plant materials were extracted and screened for phytochemicals. The antitrypanosomal activity of 70% and 100% G. kola extracts against the parasite was determined in vitro.Results: Both extracts contained saponins, tannins, carbohydrates, cardiac glycosides, and flavonoids. However, anthraquinones and alkaloids were undetected. The parasites were seen to be actively motile within the first 30 min post-incubation period in 70% hydroethanolic G. kola extract and were found dead at 40–60 min in a higher concentration of extract. After 10 min post-incubation of the parasites in 100% ethanolic extract of G. kola, the parasites were observed to be active at lower concentration but at higher concentrations of the extracts, no trypanosomes were seen.Conclusion: 100% extract induces ceasing of motility at the lesser time compared to 70% ethanolic extract. Similarly, the effect increases with increase in extract concentration. Further research should be carried out to elucidate the bioactive compounds present to have a broad knowledge on the mode of action of the compounds.

Allelopathic effects of Cynara cardunculus L. leaf aqueous extracts on seed germination of some Mediterranean weed species

It is known that the presence of weeds causes serious losses to the agricultural production, both in quantitative and qualitative terms. The major problem in modern agriculture is the environmental impact of synthetic herbicides and the increase in herbicide- resistant weed species. Allelopathic compounds can be used to develop a sustainable weed management system based on natural products. The objective of this study was to evaluate the allelopathic potential of leaf aqueous extracts (40 and 80%) obtained from Cynara cardunculus L. plant species on seed germination and mean germination time of six common weeds in Mediterranean agroecosystems: Amaranthus retroflexus L., Diplotaxis erucoides (L.) DC., Portulaca oleracea L., Lavatera arborea L., Brassica campestris L. and Solanum nigrum L. Effects varied with the weed species and the concentrations of the extracts. On average, the aqueous leaf extracts significantly reduced the final percentage of seed germination compared to the control for A. retroflexus (–58.1%), D. erucoides (–43.9%) and P. oleracea (–42.5%). The rate of germination decreased with increasing extract concentration. In C. cardunculus L. var. sylvestris the autoallelopathic activity also was demonstrated. These results are very promising in order to produce a bioherbicide based on C. cardunculus allelochemicals.

Antibacterial properties of parasitic mistletoe - Scurrula ferruginea (Jack) Danser of Brunei Darussalam

Natural products especially from plants have become subject of much interest in drug discovery. Scurrula ferruginea is parasitic mistletoe used traditionally to treat various illnesses. The aim of this study is to investigate the potential antibacterial effect of Scurrula ferruginea native to Brunei Darussalam. The plants were collected from Brunei-Muara district air-dried, pulverized into powder, extracted by water maceration and freeze dried. Later, the extract was screened by disc-diffusion assay for two bacterial strains. The positive controls were Gentamycin and Ampicillin for Staphylococcus aureus while Sulphamethoxazole was used for Escherichia coli. Dimethyl sulfoxide was the negative control for both strains. 100, 200 and 500 mg/ml of the extract were used for the assays. The extracts did not show any inhibition activity against Escherichia coli, while sulphamethoxazole, showed inhibition of 24 mm. Ampicillin, Gentamycin, 100 and 500 mg/ml extract exhibited 29, 20, 8.3 and 10.7 mm inhibition zone, respectively against Staphylococcus aureus. There was an increase in zone of inhibition on Staphylococcus aureus strain with increase in extract concentration. Further investigations including Minimum Inhibition Concentration and Minimum Bactericidal Concentration methods as well as investigation on additional bacterial strains will be conducted for confirmation of antibacterial effect of the extract.

2-Methoxystypandrone, a potent phytotoxic substance in Rumex maritimus L.

Herbicide use has raised concerns which results in the need to find an alternative approach, using natural methods, of controlling weeds. Phytotoxic substances released from plants have been used to manage weeds biologically. Rumex maritimus, belonging to the Polygonaceae family, is well known to have a wide range of biological properties. However, the phytotoxic properties of R. maritimus is not well documented. Thus, we conducted an investigation into the phytotoxic potential of R. maritimus and attempted to find out its phytotoxic substances. Leaf, stem and root extracts of R. maritimus exhibited a strong inhibitory effects on root and shoot length of Lactuca sativa L., Medicago sativa L., Lolium multiflorum Lam., Phleum pratense L. With increasing extract concentration, inhibition increased. One substance, 2-methoxystypandrone, was purified after a series of chromatography and characterized by spectral data. 2-Methoxystypandrone reduced the seedling length of Lepidium sativum at concentration ≥ 3 μM. The required 50% growth inhibition concentration of Lepidium sativum seedling for 2-methoxystypandrone was ranged 5.8–11.8 μM. Therefore, it is suggested that the phytotoxic effects of R. maritimus on the test plants may be caused due to the presence of 2-methoxystypandrone.

Antifungal effects of three medicinal crops on Phytophthora nicotianae

Tobacco black shank is one of the most harmful soil-borne diseases infected by Phytophthora parasitica. In order to probe the control method to this disease, in this study, the mycelial growth rate method was employed to investigate the antifungal effects of extracts from stem-leaf and root, root exudates, and their combination of Scrophularia ningpoensis, Chuanmingshen violaceum and Pinellia ternata The results showed that: ①Stem-leaf and root extracts of S. ningpoensis, C. violaceum and P. ternata exhibited different antifungal activities, and the inhibition increased with the increase of extract concentration. The antifungal effect of S. ningpoensis extracts at 0.5 g•mL⁻¹ was the strongest than other medicinal plants, the inhibition rate of steam-leaf and root extracts reached 74.88%, 69.27%, respectively. The inhibitory effect of C. violaceum and P. ternata was relatively lower, however, there is a significant gain effect after combination of steam-leaf and root extracts of C. violaceum. ②The root exudates of S. ningpoensis, C. violaceum and P. ternata showed fungistasis to Phytophthora nicotianae, and fungistasis was enhanced with the increase of root exudate concentration. The antifungal effect in the order of C. violaceum > S. ningpoensis > P. ternata. ③The antifungal activity of combination of extract and root exudate from S. ningpoensis was similar with the effect of C. violaceum, they were both stronger than P. ternata, and the antifungal activity for three combination were located between the antifungal activity of their extracts and root exudates. S. ningpoensis and C. violaceum can be potentially applied to prevent and control the tobacco black shank.

Asymmetric dumbbell-shaped silver nanoparticles and spherical gold nanoparticles green-synthesized by mangosteen (Garcinia mangostana) pericarp waste extracts.

Mangosteen (Garcinia mangostana) pericarp waste extract was used to synthesize gold and silver nanoparticles by a green strategy. The extract was both a reducing and stabilizing agent during synthesis. Phytochemical screening of the extract was conducted to obtain information regarding the presence/absence of primary and secondary metabolites in the extract. The in vitro antioxidant activity results demonstrated that the extract had excellent antioxidant activity, which was comparable to a standard (butylated hydroxy toluene). Spherical gold nanoparticles (gold nanoparticles green synthesized by mangosteen pericarp extract [GM-AuNPs]) with an average size of 15.37±3.99 to 44.20±16.99 nm were observed in high-resolution transmission electron microscopy (HR-TEM) images. Most interestingly, the silver nanoparticles (silver nanoparticles green synthesized by mangosteen pericarp extract [GM-AgNPs]) had asymmetric nanodumbbell shapes where one tail grew from a spherical head. The average head size was measured to be 13.65±5.07 to 31.08±3.99 nm from HR-TEM images. The hydrodynamic size of both nanoparticles tended to increase with increasing extract concentration. Large negative zeta potentials (−18.92 to −34.77 mV) suggested that each nanoparticle solution possessed excellent colloidal stability. The reaction yields were 99.7% for GM-AuNPs and 82.8% for GM-AgNPs, which were assessed by inductively coupled plasma optical emission spectroscopy. A high-resolution X-ray diffraction pattern confirmed the face-centered cubic structure of both nanoparticles. Based on phytochemical screening and Fourier transform infrared spectra, the hydroxyl functional groups of carbohydrates, flavonoids, glycosides, and phenolic compounds were most likely involved in a reduction reaction of gold or silver salts to their corresponding nanoparticles. The in vitro cytotoxicity (based on a water-soluble tetrazolium assay) demonstrated that GM-AgNPs were toxic to both A549 (a human lung cancer cell) and NIH3T3 (a mouse fibroblast cell). The cytotoxicity of GM-AgNPs on A549 cells was related to apoptotic cell death. However, GM-AuNPs did not show any significant cytotoxicity to either cell. These results suggest that GM-AuNPs have the potential to be drug delivery vehicles or carriers for pharmaceutical and biomedical applications.

English

Garcinia cola also known as “bitter cola” (Guttiferae) is a plant with a wide usage of its parts for various medicinal purposes. The seeds are chewed as aphrodisiac and for the treatment of coughs, dysentery and liver inflammation. Morinda lucida (Rubiaceae) commonly called “great morinda” has been shown to have antimalarial and anti-pyretic activities. This study aimed at evaluating the anti-infective and antioxidant properties of G. cola and M. lucida and to justify their folkloric uses. Ethanol extracts of the stem barks of G. cola (GCB) and M. lucida (MLB) were evaluated for their antimicrobial, anthelmintic and antioxidant activities. Antimicrobial activity was evaluated by determining the minimum inhibitory concentrations (MIC) using the micro broth dilution method against strains of Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Candida albicans. Anthelmintic activity was evaluated by determining the effects of the extracts on the paralytic and death times of Pheretima posthuma at concentrations of 50, 20 and 10 mg/mL using piperazine citrate (PZN) (15 mg/mL) and albendazole (ABZ) (20 mg/mL) as references. Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity using ascorbic acid (ASA) as reference standard. The results reveal that the extracts from both plants demonstrated antimicrobial activity with MIC values ranging from 50 to 80 mg/mL and 10 to 30 mg/mL for GCB and MLB, respectively. Both extracts also demonstrated a concentration dependent anthelmintic activity with decrease in paralytic and death times upon an increase in extract concentrations. GCB and MLB extract showed antioxidant activities with IC50 values, 6.830 and 342.1 µg/mL, respectively. Phytochemical screening of both extracts revealed the presence of tannins, glycosides, alkaloids and flavonoids. These findings may justify the folkloric uses of these plants. Key words: Garcinia cola, antioxidant, Morinda lucida, antimicrobial, anthelmintic.

Ganoderma lucidum and Agaricus blazei and its effects in pregnant rats with streptozotocin-induced diabetes: A morphological study of the fetuses

Nanomaterials are one of the most popular topics of technological applications in the last decade, thus it is crucial to synthesize these materials with eco-friendly methods. In the present study, ZnO nanoparticle has been biologically synthesized by using Ganoderma lucidum extract with various concentrations, and its structural, optical, morphological, and elemental characteristics are determined with XRD, UV–visible spectrometer, and SEM-EDS analyses. As well, nanofertilizer properties on Lepidium sativum (garden cress) have been investigated. It is found that structural properties of ZnO NPs have pure wurtzite phase with p63 mc space group. Optical bandgaps of nanoparticles which have not differed with the increasing extract concentration is about 3.24 eV. In SEM-EDS analysis, three different hexagonal shapes (discs, rods, and pyramidals) of nanoparticles have been observed with stoichiometric Zn and O ratios. The radicle, plumule lengths, fresh and, dry weights contents of L. sativum have been increased at rates of 45 %, 41 %, 16 %, 33 % at 250 ppm of green synthesized ZnO NPs with 25 ml extract concentration, respectively. This study is the first report on the utilization of green synthesized ZnO with G. lucidum extracts as a nano-nutrient.

Antioxidant polymeric nanoparticles containing standardized extract of Ilex paraguariensis A. St.-Hil. for topical use

Although various compounds from Ilex paraguariensis present high antioxidant activity, limitations in terms of chemical stability may be found, impacting on the formulation step. In this context, nanotechnology may be alternatively used to provide an additional protection for these compounds, avoiding degradative reactions. Different formulation parameters (eg. particle size, zeta potential, internal phase fraction) were assayed to maximize a local antioxidant action. Firstly, the extraction procedure for obtaining increased concentrations of antioxidant compounds was optimized. High stirring speed and ethanol as extractor liquid were defined as key parameters. Nanoparticles were prepared by double emulsion solvent evaporation technique. Polycaprolactone-based nanoparticles showed to be more stable than poly(lactic-co-glycolic acid)-based nanoparticles. Instead of poly(vinyl alcohol), Pluronic® was selected as surfactant because it avoids aggregate formation and provides smaller particle size. While higher polymer content contributes positively to maintaining both reduced size particle and distribution, an increased extract concentration impacted negatively on these parameters. Stability studies were also performed using skin extracts and homogenates and confirmed that nanostructures provide an additional protection. Moreover, the incorporation of Ilex extract in nanoparticles significantly reduced the amount of chlorogenic acid permeated through the skin (no ex vivo permeation until 12h for this system), extending its topical antioxidant effect.

Antioxidative capacity of hydrolyzed rapeseed cake extract and oxidative stability of fish oil-in-water emulsion added with the extract

Rapeseed cake was extracted with 80% ethanol and then fractionated with H2O (fraction I) as well as with 30% (II), 50% (III), 70% (IV), and 100% ethanol (V). Total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric-reducing antioxidant potential, and Trolox equivalent antioxidant capacity were in the order of fractions II > III > I > IV > V. The three fractions with high antioxidant activities and TPC (I, II, and III) were pooled and hydrolyzed by NaOH solution, resulting in 18.97 mg sinapic acid/g hydrolyzed extract and 21- and 2.2-fold increases in TPC and DPPH radical scavenging activity, respectively. Hydrolyzed rapeseed cake extracts (200, 500, and 1,000 ppm) and catechin (200 ppm) as a comparison were added to 10% fish oil-in-water emulsion, and their effects on oxidative stability were investigated by measuring hydroperoxide values (PV) during refrigerated storage. PVs were significantly lower in the emulsions with added hydrolyzed extract as compared to the control (p<0.05) and significantly decreased with increasing extract concentration (p<0.05) over a period of 29 days. The emulsion added with hydrolyzed extract showed higher PV than that added catechin at the same concentration (200 ppm) during 13-22 days (p<0.05), but after then, the PV was not significantly different (p>0.05). This study indicates that hydrolyzed rapeseed cake extract rich in sinapic acid may inhibit oxidation in a fish oil-in-water emulsion in a concentration-dependent manner.

Antioxidant and cytotoxic activity of Tecoma stans against lung cancer cell line (A549)

Human have been constantly using plants and plant products to overcome many diseases. The antioxidant property of the plant sources is studied to obtain an efficacious drug against cancer. The objectives of the present study is to evaluate the antioxidant and cytotoxic activity of the Tecoma stans extracts against lung cancer cell line in comparison with vincristine drug. The antioxidant activity was studied using the standard DPPH assay and the cytotoxic activity using MTT assay. DPPH assay results show that methanolic extract of T. stans in higher concentration show better antioxidant potential than the standard L-ascorbic acid. They exhibited strong antioxidant potential at 20 µg/mL concentration. The absorbance at 517 nm showed that in the range of 0.201-0.0203 compared to that of absorbance of ascorbic acid at 0.023.Cytotoxic activity was studied using MTT assay which showed that the increase in concentration of extract increases the cell death. At 100µg/mL concentration there is an increased cytotoxic activity, i.e., 99% of cell inhibition. The results of antioxidant and anticancerous activity may be positively correlated.

English

Newcastle disease virus is a paramyxovirus which causes Newcastle disease in birds. Investigation was done on the effect of leaf extract of Phyllanthus amarus against Newcastle disease virus (NDV) using an in-ovo assay. Nine to eleven day-old viable embryonated chicken eggs (ECE) were used for the assay, these were divided into six groups of six eggs each. Methanol, aqueous and n-hexane extracts of the plant leaves were administered to the various groups at concentrations varying from 50 to 5 mg/ml. Embryonated eggs were incubated and embryo survival was monitored daily. Negative control and diluents control groups received phosphate buffer saline (PBS) and dimethly suphoxide (DMSO), respectively. The other group was uninoculated while a virus control group received 100 EID50/0.1 ml NDV alone. Bacteria free allantoic fluid from the embryonated eggs in different treatment groups were harvested and collected for spot hemagglutination (HA) test and HA assay to detect the presence of NDV viral particles and the viral titre, respectively. Leaf extracts were assayed for presence of phytochemicals and antioxidant potentials. It was observed from the results that the extract was toxic to the embryo at a concentration above 50 mg/ml and further results showed that the HA viral titre reduction was directly proportional to increasing extract concentration. The phytochemical assays of leaf extract revealed the presence of phytochemicals including alkaloids, tannins, saponins, flavonoids, phenols, steroids, glycosides. The current findings have demonstrated that leaf extract from P. amarus has potentials of medicinal value as well as antiviral activity against NDV in-ovo. Further experimental assays using live animal models are recommended to validate the use of P. amarus plant extract in therapeutic measure in chickens. Key words: Antiviral, Phyllanthus amarus, Newcastle disease virus (NDV), embryonated chicken eggs (ECE).

Gel Formulation of Ethanol Extract of Mangosteen Peel (Garcinia mangostana L.) as A Medication for Burns in Wistar Rats

Background : Mangosteen peel (Garcinia mangostana L.) has been shown to stimulate the regeneration of damaged body cells and have an antimicrobial activity that can be beneficial in healing burns. Therefore, it is necessary to make it into a gel dosage form that has the advantages of being easily washed with water, high adhesion, cooling of the skin, and good drug release. Objective : To determine the effect of varying concentrations of ethanol extract of mangosteen peel in a gel formulation on wound healing in burns and the physical properties of the gel. Methods : Mangosteen peel extract was obtained by maceration method using ethanol 70%. This extract was formulated in a gel dosage form with variations of extract concentration, namely F I (5%), F II (10%), and F III (15%). The gels were then tested for their physical properties (organoleptic, homogeneity, pH, spreadability, adhesiveness, and physical stability) and their activity against burns experimentally using mice as test animals. Burns were made by using a hot plate with an area of 2 cm x 2 cm. Results : The increase of extract concentration could increase spreadability (p>0.05), adhesiveness (p>0,05), and percentage of healing activity against burns as shown by a significant difference between FI and FIII. On the other hand, the difference in the concentration of the extract did not affect pH (all formulations have pH of 3.5); all formulas also remained homogenous and stable after centrifugation. Conclusion : The best physical properties and wound healing activity for burns was shown by the gel with the ethanol extract of mangosteen peel at a concentration of 15%.

Evaluation of phytotoxic potential and identification of phytotoxic compounds in Rumex maritimus

Rumex maritimus (Polygonaceae) is an annual herb and is well known for its use in medicinal treatments. Although the pharmacological properties of R. maritimus are well documented, no phytotoxic activity of R. maritimus has yet been found. Therefore, we investigated the phytotoxic potential of R. maritimus to identify phytotoxic compounds. Inhibitory activity was found in aqueous methanol extracts of R. maritimus on the seedling growth of cress, rapeseed, barnyard grass, and foxtail fescue, in which inhibition increased with increasing extract concentration. Two compounds were isolated using chromatography, and using spectroscopy their structure was determined as 5,7-dihydroxyphthalide and altechromone A. 5,7-Dihydroxyphthalide significantly inhibited cress seedling growth by 27.2–43.0% of control seedlings at 3 mM, whereas altechromone A inhibited seedling growth by 65.4–66.3% at 0.01 mM. The concentrations required for 50% inhibition of cress seedling growth were 1.73–2.48 mM for 5,7-dihydroxyphthalide and 0.66–1.41 mM for altechromone A. These results indicate that the compounds 5,7-dihydroxyphthalide and altechromone A may contribute, to a certain extent, to the phytotoxic activity of R. maritimus.

Longan seed and peel as environmentally friendly corrosion inhibitor for mild steel in acid solution: Experimental and theoretical studies

Longan seed and peel were extracted and used for impeding the corrosion of mild steel in hydrochloric acid solution. Experimental analyses indicate that the water extract of Longan’s seed and peel, a mixed type inhibitor, can be chemically adsorbed onto the steel surface, and its inhibition effect rises with increasing extract concentration. To understand the adsorption mechanism and the contributions of the four main compounds of the extract to corrosion protection effect, quantum chemical methods and infrared spectrum were also employed. Theoretically, four main antioxidant compounds were regarded as effective components in the water extract of Longan’s seed and peel.

Differences in leaf functional traits and allelopathic effects on seed germination and growth of Lactuca sativa between red and green leaves of Rhus typhina

The leaves of the invader Rhus typhina are heterochromatic in different periods during its life cycle. This study aims to address the differences in leaf functional traits and allelopathic effects on seed germination and growth of Lactuca sativa between green and red leaves of R. typhina. The leaf chlorophyll and N concentrations, single-leaf wet and dry weights, and leaf thickness of green leaves of R. typhina were significantly higher than those of red leaves of R. typhina but specific leaf area and leaf moisture content demonstrated the opposite. Thus, the resource investment per unit area and per lamina of red leaves of R. typhina is significantly lower than that of green leaves of R. typhina due to the low leaf chlorophyll concentration for red leaves. Seed germination and growth of L. sativa inhibited significantly with increasing extract concentrations both of R. typhina green and red leaves. Thus, more allelochemicals may be released into the invaded ecosystems under the invasion of R. typhina with increasing invasion degree and time presumably and then trigger more noticeably allelopathic effects on the performance of associated plant species. Allelopathic effects on seed germination and growth of L. sativa of R. typhina red leaves are obviously higher than that of R. typhina green leaves. The main reason may be that the type of R. typhina red leaves is aged and the free nutrient compositions have been transported to other position but the main secondary metabolites retained in the aged leaves. The forest management for R. typhina might be better progressive in advance before the brilliant red foliage of R. typhina occurs before mid-autumn generally to obtain effective invasion prevention and control.

Isolation and identification of two potential phytotoxic substances from the aquatic fern Marsilea crenata

Organic agriculture emphasized using of biologically originated herbicides and phytotoxic substances are being considered as a replacement to chemical herbicides. Marsilea crenata is an aquatic perennial fern distributed in the South-East Asian countries and is well known for various biological properties. However, to date, there has been no report that addresses the phytotoxicity of Marsilea crenata. Therefore, we explored phytotoxic properties and phytotoxic substances from Marsilea crenata. An aqueous methanol extracts of Marsilea crenata showed inhibition on the seedling growth of cress, lettuce, alfalfa, barnyard grass, Italian ryegrass, and foxtail fescue. Inhibition increased with increasing extract concentration. The extract was purified by several chromatographic steps and two phytotoxic substances were isolated and identified by spectroscopic analysis as loliolide and isololiolide. At the concentration of 30 μM, loliolide and isololiolide inhibited seedling growth of cress and barnyard grass by 41.3 to 51.1%, and 58.15 to 87.5% of control seedlings, respectively. The concentrations required for 50% inhibition of cress and barnyard grass seedlings ranged from 32.1 to 128.5 μM for loliolide, 37.0 to 176.2 μM for isololiolide. These results suggest these compounds may be responsible for phytotoxic effects of Marsilea crenata extract and could be an important part of organic agriculture.

Investigation of Antioxidant and Antibacterial Properties of Leaf, Root, Fruit and Stem Extracts of Trichopus zeylanicus from South India

Objective: To investigate the total phenols, flavonoids and carotenoids content, antioxidant and antibacterial potential profile of leaf, root, fruit and stem extracts of the Trichopus zeylanicus with five major solvents, that is, water, methanol, chloroform, ethyl acetate, and petroleum ether. Results: The total phenols, flavonoids and carotenoids contents of fruit methanol extract of T.zeylanicus was found to be 85.15±0.223 mg catechol equivalent per gram, 165.5622±1.236 mg quercetin equivalent per gram and 84.47273 ±0.531 mg β-Carotein equivalent per gram respectively which are higher than the activity of other extracts. The methanol extracts showed more reducing power, metal chelating activity, hydrogen peroxide scavenging and phosphomolybdenum assays than other extracts and their activity increased with increasing concentration of extracts. The hydroxyl radical scavenging activity of fruit methanol extract is quite comparable to the standard mannitol of the assay and its antibacterial potential is the best way to cope with infectious action of bacteria. Conclusion: The remarkable activity showed by the plant extracts could be attributed to the synergic effect of the active compounds present in it. Among the extracts, methanol was found to be the better solvent to extract natural products to get maximum medicinal benefits.