NPC Natural Product Communications EDITOR-IN-CHIEF DR. PAWAN K AGRAWAL Natural Product Inc. 7963, Anderson Park Lane, Westerville, Ohio 43081, USA agrawal@naturalproduct.us EDITORS PROFESSOR ALEJANDRO F. BARRERO Department of Organic Chemistry, University of Granada, Campus de Fuente Nueva, s/n, 18071, Granada, Spain afbarre@ugr.es PROFESSOR ALESSANDRA BRACA Dipartimento di Chimica Bioorganicae Biofarmacia, Universita di Pisa, via Bonanno 33, 56126 Pisa, Italy braca@farm.unipi.it PROFESSOR DEAN GUO State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100083, China gda5958@163.com PROFESSOR YOSHIHIRO MIMAKI School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Horinouchi 1432-1, Hachioji, Tokyo 192-0392, Japan mimakiy@ps.toyaku.ac.jp PROFESSOR STEPHEN G. PYNE Department of Chemistry University of Wollongong Wollongong, New South Wales, 2522, Australia spyne@uow.edu.au PROFESSOR MANFRED G. REINECKE Department of Chemistry, Texas Christian University, Forts Worth, TX 76129, USA m.reinecke@tcu.edu PROFESSOR WILLIAM N. SETZER Department of Chemistry The University of Alabama in Huntsville Huntsville, AL 35809, USA wsetzer@chemistry.uah.edu PROFESSOR YASUHIRO TEZUKA Institute of Natural Medicine Institute of Natural Medicine, University of Toyama, 2630-Sugitani, Toyama 930-0194, Japan tezuka@inm.u-toyama.ac.jp PROFESSOR DAVID E. THURSTON Department of Pharmaceutical and Biological Chemistry, The School of Pharmacy, University of London, 29-39 Brunswick Square, London WC1N 1AX, UK david.thurston@pharmacy.ac.uk HONORARY EDITOR PROFESSOR GERALD BLUNDEN The School of Pharmacy & Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2DT U.K. axuf64@dsl.pipex.com ADVISORY BOARD Prof. Berhanu M. Abegaz Gaborone, Botswana Prof. Viqar Uddin Ahmad Karachi, Pakistan Prof. Øyvind M. 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All issues are dispatched by airmail throughout the world, excluding the USA and Canada. NPC Natural Product Communications Antimicrobial Activity of Crude Methanolic Extract from Phyllanthus niruri 2013 Vol. 8 No. 4 493 - 496 Darah Ibrahim, Lim Sheh Hong* and Ninthianantham Kuppan Industrial Biotechnology Research Laboratory (IBRL), School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia limshehhong77@gmail.com Received: February 7th, 2013; Accepted: February 21st, 2013 The antibacterial efficiency of the methanolic extract of Phyllanthus niruri Linn. was investigated against pathogenic bacteria responsible for common infections of skin, and urinary and gastrointestinal tracts. The extract demonstrated antibacterial activities against all the Gram-positive and Gram-negative bacteria tested. The results obtained suggested that at higher concentrations the extract would eradicate the growth of bacterial cells. The bacterial cells, after exposure to the extract, showed complete alteration in their morphology, followed by collapse of the cells beyond repair. The study revealed that the methanolic extract of P. niruri may be an effective antibacterial agent to treat bacterial infections since the extract exhibited significant antimicrobial potency, comparable with that of the standard antibiotic chloramphenicol. Keywords: Antimicrobial activity, Phyllanthus niruri, Antibiotic, Bacteria, Minimum inhibitory concentration. Although pharmacological industries have produced considerable number of commercial antibiotics but resistance in pathogens toward these drugs has risen to a point of global concern. This situation forces scientists to search for new antimicrobial substances from various sources. Therefore, there is a need to develop alternative antimicrobial drugs with diverse chemical structure and novel mechanism of action for the treatment of infectious diseases from medicinal plants in order to curb this problem. Herbal medicines have been developed not only as a way to improve ancient traditional therapeutics, but also as an alternative solution for health problems. Plants constitute an important source of active natural products which differ widely in terms of structure and therapeutic properties. The continued investigation into the secondary plant metabolites for anti-infective agents has gained importance in recent years because of the alarming increase in resistance of pathogenic microorganisms to existing antibiotics [1]. Phyllanthus niruri Linn. (Euphorbiaceae) or locally known in Malaysia as dukung anak is considered as a weed which later is accepted as a valuable medicinal plant widely used to treat various diseases. P. niruri is a small, erect annual herb that grows 30-50 cm high and are highly distributed in most tropical and sub-tropical countries. It is reported to have inhibitory effect on human immunodeficiency virus where the alkaloidal extract of P. niruri is found to exhibit sensitive inhibitory response on cytopathic effects induced by both the strains of human immunodeficiency virus on human MT-4 cells [2]. It’s extract has been used to treat microbial infections which caused diarrhea, dysentery, tuberculosis, cough and vaginitis [3] besides exhibiting anti-tumor and anticarcinogenic activities [4, 5]. Due to its various medicinal purposes, therefore the present study is focused mainly on the evaluation of methanolic extract of P. niruri leaves for its activity against pathogenic bacteria which causes infections in human. Its effect on the selected bacterial growth and structure degeneration were studied and evaluated. In this study, methanolic extract of P. niruri was selected because the extract showed good activity against the test bacteria. The higher activity of the methanolic extracts may be due to higher solubility of the active compounds in these solvents. Methanol is a polar solvent and has a higher power to extract the active antibacterial compounds in the plant which exhibited higher activity. Table 1 shows that Gram positive bacteria (B. cereus, B. subtilis and S. aureus) are more susceptible than the Gram negative bacteria (E. coli, P. rettgeri and P. aeruginosa) based on larger inhibition zones produced by them which were between 12.00 – 15.00 mm compared to 7.00 – 8.00 mm, respectively. This condition can be observed clearly on the MIC values of the extract against test bacteria (Table 1), where Gram positive bacteria exhibited lower MIC values of 3.13 – 6.25 mg/mL whereas the Gram negative bacteria exhibited higher MIC values of 25.00 mg/mL. Further study was concentrated on B. cereus since it’s showed the lowest MIC value. Table 1: Antimicrobial activity of the methanolic extract of P. niruri L. leaves on pathogenic microorganisms. Microorganism Gram positive bacteria : Bacillus cereus Bacillus subtilis Staphylococcus aureus Gram negative bacteria: Escherichia coli Proteus rettgeri Pseudomonas aeruginosa Diameter zone of inhibition (mm) Methanolic extract Chloramphenicol (100.0 mg/mL) (30 µg/mL) MIC (mg/mL) 14.0±0.3 12.0±0.4 15.0±0.3 20.00±0.3 21.00±0.2 21.00±0.3 3.13 6.25 6.25 7.0±0.3 8.0±0.5 7.0±0.2 22.00±0.2 20.00±0.3 20.00±0.4 25.00 25.00 25.00 Time-kill studies were performed over a period of 48 hours with the B. cereus cells being exposed to 1/2MIC (1.56 mg/mL), MIC (3.13 mg/mL) and 2MIC (6.25 mg/mL) values of the extract and the results are shown in Figure 1. At 1/2MIC (1.56 mg/mL) the extract demonstrated a drastic drop in OD after 12 hours, which leads to the stationary phase of the bacterial growth compared to the control. At the values of MIC (3.13 mg/mL) and 2MIC (6.25 mg/mL), the extract produced cell eradication after 12 hours. Based on the results obtained from the time-kill studies, it was obviously seen the potency of the methanolic extract of P. niruri leaves as antibacterial agents against pathogenic bacteria. 494 Natural Product Communications Vol. 8 (4) 2013 Figure 1: Effects of methanolic extract of P. ninuri leaves on the growth of Bacillus cereus at different concentration of the extract The results obtained from this study proved that P. niruri leaves methanolic extract can be used to treat bacterial infections topically as it acted straight to the cell wall of a target bacteria. In order to assure the write time of using the extract against the bacteria, we conducted a study on the effect of addition the extract to the bacterial growth profile. Figure 2 shows that the control cells grew well and achieved its logarithmic profile at 8 hours of cultivation time, then it entered the initial stationary phase at 12 hours of cultivation time, followed by a stationary phase from 20 hours onward. Therefore, the additions of the extract were done at 8, 16 and 24 hours of cultivation time in response to those phases. The results revealed that the growth of the treated cells decreased once the extract was added without having any exception on the time of addition. This condition is good in the sense that the extract can be used at any time of the bacterial growth to treat its infection. Figure 2: Effect of addition the methanolic extract of P. niruri leaves (at MIC value of 3.13 mg/mL) on the growth profile of Bacillus cereus. Arrows indicated the time of extract addition to the bacterial culture. To have a clearer view of what happening in time-kill studies, the SEM studies were performed and the results revealed that the extract produced considerable morphological changes in the bacterial cells. Figures 3A -3D represent the morphological changes of the non- treated and treated B. cereus. Figure 3A shows the SEM micrographs of bacterial cells without the methanolic extract treatment. The figure revealed the normal rod shape cell structure without any shrinkage or cavity formation as the surface was smooth and regular. Figure 2B shows the morphology of the cell after 12 hours of treatment with the extract. The bacterial cells started to show multiple defects with many of cells exhibited crumpled or shrunken cell surface. Figure 3C revealed more formation of crumpled cells and some the cells formed cavities. After 36 hours of exposure (Figure 3D, the bacterial cells were seemed to be totally deformed and collapsed cells were seen. The cells were collapsed, clumping together and hence lost their original rod shape as compared to the control cells in Figure 3A. Ibrahim et al. A B C D Figure 3: SEM micrographs of the untreated and treated Bacillus cereus cells after exposure to methanolic extract P. niruri. (A) Control, the untreated cells, (B) 12, (C) 24 and (D) 36 hours of treatment. The use of crude extracts of plants parts and phytochemicals of known antimicrobial properties can be of great significance in the therapeutic treatments. In fact, many plants have been used due to their antimicrobial properties which are actually the secondary metabolites synthesize by the plants. The present study has shown that methanolic extract of P. niruri leaves has promising antibacterial activity and this is probably why the plant is widely used in traditional medicine [6]. Generally, the methanol extract was more active than other extracts [7]. This may be attributed to the polarity of methanol and it capability to extract more compound from the plant samples especially phenolic and polyphenolic group of compounds [8, 9]. Even though there were reports that methanol extract demonstrated inhibitory effects to B. subtilis, P. aeruginosa, and S. aureus but not E. coli [10], but recent research activities on antibacterial activities of crude extracts have implicated the methanol extract for being more active than the other solvents extracts [11, 12]. The activity of the plant against both Gram positive and Gram negative bacteria can be indicative of the presence of broad spectrum antibiotic compounds or simply general metabolic toxins in the plant. The antimicrobial activity of the extracts of P. niruri may be due to the presence of lignans (like phyllanthin and hypophyllanthin), flavonoids (like quercetin), astragalin, triterpenoids, glycosides, and tannins (ellagitannins), in the plant extract [13, 14]. Phytochemical constituents like flavonoids are known to prevent gastric ulcer due to the astringent and antimicrobial properties, which appear to be responsible for gastroprotective activity, as reported by Okolo et al. [15]. P-cymene, a monoterpenoid has also reported to have good antimicrobial properties [6, 16]. In this study three Gram positive (B. cereus, B. subtilis and S. aureus) and three Gram negative (E. coli, P. rettgeri and P. aeruginosa) were used as test microorganisms. All these are pathogenic bacteria that are known to cause several diseases and infections in humans and animals. For instance, S. aureus and P. aeruginosa are most common pathogens causing serious infections while E. coli is an opportunistic pathogen at the site of cut wound. Antimicrobial activity of Phyllanthus niruri The MIC values of the extract against all the test bacteria were determined using agar diffusion method and the results showed that MIC values for Gram positive bacteria were between 3.13 to 6.25 mg/mL which were more susceptible than Gram negative bacteria which exhibited the MIC values of 25.00 mg/mL. In the present study Gram positive bacteria were found to be more susceptible to the plant extract than Gram negative bacteria which corroborated the previous reports that plant extracts are more active against Gram positive bacteria [17-19]. This may be attributed to the fact that these two groups differ in their structure of the cell wall components. The same characteristics were observed in other antimicrobial studies of plant extract against pathogenic bacteria [18, 19]. Hyde et al. [20] suggested that the morphological changes of the antibiotic-treated bacteria occur when the antimicrobial agent attacked the cell membrane. In this case, the bioactive compound of the methanolic extract of P. niruri leaves that locked on the cell surface structure had permeabilized the bacterial membranes. Any disruption in cell wall integrity will have a great influence in bacterial growth. This prediction was coincided well with the findings of Sasidharan et al. [21] who reported the methanolic extract of macroalgae Gracilaria changii exerted its inhibitory effect on the cell wall of the bacterial cells which led to the complete damage of the cells. Various studies were reported to investigate the mechanism of actions involved in bacterial killing process. Among them are the interactions of antibacterial compound with the cell membrane [22]. Gram-negative bacteria are considered to be more resistant due to their outer membrane which acting as a barrier to many environmental substances including antibiotics [23]. This outer membrane includes the asymmetric distribution of the lipids with phospholipids and lipopolysaccharide (LPS) located in the inner and outer leaflets, respectively [24]. This characteristic that is absent in the Gram- positive bacteria might have acted as the additional barrier that hinders the movement of foreign substance into the cell [25]. In addition, the cell wall of Gram- positive bacteria contains lipotheichoic acids (LTA) that represent unique and essential structural components to the cells and should be good drug targets to the bioactive compounds of P. niruri. The results of the study show that the methanolic extract of P. niruri leaves exhibited appreciable antibacterial properties inhibiting growth of Gram positive and negative bacteria. It could serve as useful source for new antimicrobial agents. Experimental Collection, processing and extraction of plant sample: The fresh sample of P. niruri leaves was collected around the Penang Island and brought back immediately to the laboratory in a sterile plastic bags. The leaves were rinsed thoroughly under running tap water and the clean samples were then dried in an oven at 45C for 4-7 days until they were completely dried before grinding them into powder form. Approximately 40 g of dried powder form of the plant sample was soaked in 400 ml of 100% methanol at room temperature (30±2C) for three consecutive days. The mixture was filtered using a muslin cloth and followed by Whatman No. 1 filter paper. The filtrate was then concentrated in a rotary evaporator under reduced pressure until oily paste formed and kept at cool dry place until further used. Microorganisms and cultural maintenance: Six pathogenic bacteria species which consisted of three Gram positive (Bacillus cereus, B. subtilis and Staphylococcus aureus) and three Gram negative (Escherichia coli, Proteus rettgeri and Pseudomonas Natural Product Communications Vol. 8 (4) 2013 495 aeruginosa) bacteria which were obtained from the Industrial Biotechnology Research Laboratory Culture Collection, School of Biological Sciences, Universiti Sains Malaysia were used throughout the study. The bacterial cultures were maintained on nutrient agar slants at 37C for 24 h. All the cultures were kept at 4C until further used. Subculturing was done at every four weeks to maintain their viability. Antibacterial activity: The antibacterial activity of the extract against the test bacteria were determined following the method described by Tong et al. [26] with slight modifications. Test bacteria were cultured on nutrient agar plates and incubated at 37º C for 24 hours. Bacterial suspensions were prepared by inoculating one loopful of a pure colony into 5.0 mL of sterile distilled water. Sufficient inoculums were added until the turbidity equal to 0.5 McFarland standards which approximately equivalent to 1.5x105 cells per mL. One milliliter of the suspension was added into 15.0 mL of sterilized molten nutrient agar aseptically. The mixtures were mixed well by swirling the plates left and right and then they were left on the bench to solidify. The commercial antibiotic disk GF A (Whatman) with 6.0 mm diameter was used to screen the antibacterial activity. Each of the sterile disks was then impregnated with 20 µL of the extracts, which corresponding to 100.0 mg/mL of extract stock. Chloramphenicol at the concentration of 30 µg/mL was used as a positive control. On the other hand, 100% methanol was used as a negative control. All the impregnated disks were air dried before placing them on the agar surface. The plates were incubated at 37C for 24 h and the antibacterial activity was determined by measuring the diameter of the inhibition zones formed around the disks. Determination of minimum inhibitory concentrations: The determination of minimum inhibitory concentration (MIC) was performed using macrodilution method [27]. Briefly, different extract preparations were subjected to a serial dilution using sterile nutrient broth medium as a diluents to give final crude extract concentrations between 1.275 and 200.000 mg/mL. The tubes were inoculated with the bacterial suspension (20 µL/mL broth), homogenized, and incubated at 37°C for 24 h. The lowest dilution of the extract that retained its inhibitory effect resulting in no growth (absence of turbidity) of a microorganism was recorded as the MIC value of the extract. The bacterial growth was indicated by the turbidity. Each test was performed in triplicate and repeated twice. A control experiment was run in parallel to study the impact of the solvent itself (without plant component) on growth of the test bacteria. Time-kill study of Bacillus cereus in the presence of methanolic extract of Wedelia chinensis leaves: Bacterial suspension of B. cereus was prepared as described previously and was harvested by centrifugation, washed twice with sterile distilled water and resuspended in sterile distilled water. The suspension was adjusted using the McFarland standard. The extract was added in to 25 mL of nutrient broth in a 50 mL Erlenmeyer flask to achieve concentrations of 0 (control), 1.56 (1/2MIC), 3.13 (MIC) and 6.25 (2MIC) mg/mL after addition of the inocula [28]. The experiments were conducted in triplicate and all the flasks were incubated in a shaker (Infors HT Ecotron) incubator at 37C with agitation at 150 rpm. One milliliter of the mixture within each flask was withdrawn at every 4 hourly intervals starting from 0 hour until 48 hours of cultivation and the bacterial cell growth was monitored by measuring optical density at 540 nm. 496 Natural Product Communications Vol. 8 (4) 2013 Scanning electron microscope observations: The bacterial suspension was prepared as described previously. To each sample, 1.0 mL of the 24 h old bacterial suspension was inoculated in a 50.0 mL conical flask containing 30.0 mL of sterilized nutrient broth and incubated in a shaker at 37C, 150 rpm for 18 h. The bacterial suspension was then added to the extract stock solution (the final concentration in each flask was at the MIC value) and incubated at the required incubation time (12, 24 and 36 h). As for a negative Ibrahim et al. control, a conical flask containing bacterial suspension was added with 1.0 mL of 100% methanol. 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Sirat, NorAzah Mohamad Ali and Azrina Aziz Effect on Emotional Behavior and Stress by Inhalation of the Essential oil from Chamaecyparis obtusa Hikaru Kasuya, Erika Hata, Tadaaki Satou, Masaki Yoshikawa, Shinichiro Hayashi, Yoshinori Masuo and Kazuo Koike Chemical Composition and Antibacterial Activity of Rhizome Oils from Five Hedychium Species Ratchuporn Suksathan, Siriwoot Sookkhee, Somboon Anuntalabhochai and Sunee Chansakaow Chemical Composition and Antimicrobial Activity of Three Essential Oils from Curcuma wenyujin Jingjing Zhu, Agnieszka D. Lower-Nedza, Meng Hong, Song Jiec, Zhimin Wang, Dong Yingmao, Christine Tschiggerl, Franz Bucar and Adelheid H. Brantner Essential Oil Composition and Antimicrobial Activity of Aerial Parts and Ripe Fruits of Echinophora spinosa (Apiaceae) from Italy Daniele Fraternale, Salvatore Genovese and Donata Ricci Composition and in vitro Anticancer Activities of the Leaf Essential Oil of Neolitsea variabillima from Taiwan Yu-Chang Su, Kuan-Ping Hsu, Eugene I-Chen Wang and Chen-Lung Ho 509 513 515 519 523 527 531 Review/Account Natural Products from Marine Algae of the Genus Osmundaria (Rhodophyceae, Ceramiales) Kelvin Osako and Valéria Laneuville Teixeira Phenols, Alkaloids and Terpenes from Medicinal Plants with Antihypertensive and Vasorelaxant Activities. A Review of Natural Products as Leads to Potential Therapeutic Agents Francesco Maione, Carla Cicala, Giulia Musciacco, Vincenzo De Feo, Anibal G. Amat, Armando Ialenti and Nicola Mascolo Diosmin – Isolation Techniques, Determination in Plant Material and Pharmaceutical Formulations, and Clinical Use Anna Bogucka – Kocka, Michał Woźniak, Marcin Feldo, Janusz Kocki and Katarzyna Szewczyk 533 539 545 Natural Product Communications 2013 Volume 8, Number 4 Contents Original Paper Anti-melanogenesis Constituents from the Seaweed Dictyota coriacea Ryeo Kyeong Ko, Min-Chul Kang, Sang Suk Kim, Tae Heon Oh, Gi-Ok Kim, Chang-Gu Hyun, Jin Won Hyun and Nam Ho Lee Methyl Carnosate, an Antibacterial Diterpene Isolated from Salvia officinalis Leaves Elisa Climati, Fabio Mastrogiovanni, Maria Valeri, Laura Salvini, Claudia Bonechi, Nilufar Zokirzhonovna Mamadalieva, Dilfuza Egamberdieva, Anna Rita Taddei and Antonio Tiezzi Cytotoxicity of Meroterpenoids from Sargassum siliquastrum against Human Cancer Cells Jung Im Lee, Myoung K. Kwak, Hee Y. Park and Youngwan Seo Isolation of Methyl 27-caffeoyloxyoleanolate – A New Oleanane Triterpenoid from the Roots of Hibiscus vitifolius Duraisamy Ramasamy and Ariamuthu Saraswathy Synthesis and Cytotoxic Activity of New Betulin and Betulinic Acid Esters with Conjugated Linoleic Acid (CLA) Barbara Tubek, Paweł Mituła, Natalia Niezgoda, Katarzyna Kempińska, Joanna Wietrzyk and Czesław Wawrzeńczyk Analysis of Pyrrolizidine Alkaloids and Evaluation of Some Biological Activities of Algerian Senecio delphinifolius (Asteraceae) Soukaina Tidjani, Philippe N. Okusa, Amar Zellagui, Laetitia Moreno Y Banuls, Caroline Stévigny, Pierre Duez and Salah Rhouati Berbanine: a New Isoquinoline-isoquinolone Alkaloid from Berberis vulgaris (Berberidaceae) Anna Hošťálková, Zdeněk Novák, Milan Pour, Anna Jirošová, Lubomír Opletal, Jiří Kuneš and Lucie Cahlíková Dicentrine Production in Callus and Cell Suspension Cultures of Stephania venosa Tharita Kitisripanya, Jukrapun Komaikul, Nirachara Tawinkan, Chuennapha Atsawinkowit and Waraporn Putalun New Flavan and Alkyl α,β-Lactones from the Stem Bark of Horsfieldia superba Nabil Ali Al-Mekhlafi, Khozirah Shaari, Faridah Abas, Ethyl Jeyaseela Jeyaraj, Johnson Stanslas, Shaik Ibrahim Khalivulla and Nordin H. Lajis New Flavonol Triglycosides from the Leaves of Soybean Cultivars Yoshinori Murai, Ryoji Takahashi, Felipe Rojas Rodas, Junichi Kitajima and Tsukasa Iwashina Melitidin: A Flavanone Glycoside from Citrus grandis ‘Tomentosa’ Wei Zou, Yonggang Wang, Haibin Liu, Yulong Luo, Si Chen and Weiwei Su Two New Chalcones from the Flowers of Clerodendrum inerme Shaik Khadar Shahabuddin, Rachakunta Munikishore, Golakoti Trimurtulu, Duvvuru Gunasekar, Alexandre Deville and Bernard Bodo A Novel Phenolic Compound from Phyllanthus emblica Gaimei She, Ruiyang Cheng, Lei Sha, Yixia Xu, Renbin Shi, Lanzhen Zhang and Yajian Guo Anti-austeric Activity of Phenolic Constituents of Seeds of Arctium lappa Yasuhiro Tezuka, Keiichi Yamamoto, Suresh Awale, Feng Li, Satoshi Yomoda and Shigetoshi Kadota Bioactive Lignans from the Leaves and Stems of Schisandra wilsoniana Guang-Yu Yang, Rui-Rui Wang, Zhong-Hua Gao, Yin-Ke Li, Liu-Meng Yang, Xiao-Nian Li, Shan-Zhai Shang, Yong-Tang Zheng, Wei-Lie Xiao and Han-Dong Sun Antioxidative / Acetylcholinesterase Inhibitory Activity of Some Asteraceae Plants Ivana Generalić Mekinić, Franko Burčul, Ivica Blažević, Danijela Skroza, Daniela Kerum and Višnja Katalinić Antioxidant and Antimicrobial Activities, and Phenolic Compounds of Selected Inula species from Turkey Alper Gökbulut, Onural Özhan, Basri Satılmış, Kadir Batçıoğlu, Selami Günal and Engin Şarer Two New Dihydrostilbenoid Glycosides Isolated from the Leaves of Litsea coreana and their Anti-inflammatory Activity Wenjian Tang, Weili Lu, Xiaoqing Cao, Yilong Zhang, Hong Zhang, Xiongwen Lv and Jun Li Inhibitory Activity of Benzophenones from Anemarrhena asphodeloides on Pancreatic Lipase Yang Hee Jo, Seon Beom Kim, Jong Hoon Ahn, Qing Liu, Bang Yeon Hwang and Mi Kyeong Lee Identification and Quantification of Furanocoumarins in Stem Bark and Wood of Eight Algerian Varieties of Ficus carica by RP-HPLC-DAD and RP-HPLC-DAD-MS Samia Rouaiguia-Bouakkaz, Habiba Amira-Guebailia, Céline Rivière, Jean-Claude Delaunay, Pierre Waffo-Téguo and Jean-Michel Mérillon UPLC-Q-TOF/MS Coupled with Multivariate Statistical Analysis as a Powerful Technique for Rapidly Exploring Potential Chemical Markers to Differentiate Between Radix Paeoniae Alba and Radix Paeoniae Rubra Nian-cui Luo, Wen Ding, Jing Wu, Da-wei Qian, Zhen-hao Li, Ye-fei Qian, Jian-ming Guo and Jin-ao Duan Antimicrobial Activity of Crude Methanolic Extract from Phyllanthus niruri Darah Ibrahim, Lim Sheh Hong and Ninthianantham Kuppan Cellulose Contents of Some Abundant Indian Seaweed Species Arup K. Siddhanta, Sanjay Kumar, Gaurav K. Mehta, Mahesh U. Chhatbar, Mihir D. Oza, Naresh D. Sanandiya, Dharmesh R. Chejara, Chirag B. Godiya and Stalin Kondaveeti Anti-inflammatory Potential of Silk Sericin Pornanong Aramwit, Pasarapa Towiwat and Teerapol Srichana Composition of Essential Oil from Aerial and Underground Parts of Geum rivale and G. urbanum Growing in Poland Aleksandra Owczarek, Jan Gudej and Agnieszka Kice Continued Inside backcover View publication stats Page 427 429 431 433 435 439 441 443 447 453 457 459 461 463 467 471 475 479 481 485 487 493 497 501 505