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Antimicrobial Activity Of Phyllanthus Muellerianus (Kuntze) Excell Stem Bark: From Crude Extrac To Bioactive Compound
No full textInitial characterization of stem bark extracts from Phyllanthus muellerianus as source of new natural entities with anti-cholinesterase properties
No full textChromatographic approaches for the characterization of stem bark extracts from phyllanthus muellerianus (Kuntze) excel.
No full textINTRODUCTION
[The plants of the genus Phyllanthus (Euphorbiaceae) are widely distributed in most tropical and subtropical countries, and have long been used in folk medicine to treat kidney and urinary bladder disturbance, intestinal infections, diabetes and hepatitis B [1]. Phyllanthus muellerianus (Kuntze) Excell is a medicinal plant widespread in the tropical region of West Africa and the Baka pygmies from Cameroon prepare a water decoction of Phyllanthus muellerianus stem bark which is used as a remedy for tetanus and wound infections [2,3].] In our previous work [4] the antimicrobial properties of P. muellerianus stem bark methanol extract have been demonstrated against different micro-organisms such as Clostridium sporogenes, Streptococcus mutans and Streptococcus pyogenes. Bioassay-guided isolation together with preliminary phytochemical investigations suggested the presence of a basic fraction responsible for the biological activity.
MATERIALS AND METHODS
[Amberlite IR120-H resin was used for a preliminary purification process. HPLC method based on RP-18 analytical column with a binary mobile phase water/acetonitrile (TFA 0,05%) under gradient elution. A second analytical method based on a cation-exchange column with a binary mixture of 80% ammonium acetate buffer (20 mM) and 20% acetonitrile was developed. The separation procedure was carried out under isocratic elution at a flow rate of 0.7 ml/min. UV detection was fixed at 254 nm for both methods.]
RESULTS AND DISCUSSION
[The basic fraction has been preliminary purified by means of a 'catch and release' process: the crude methanol extract was dissolved in methanol and Amberlite IR120-H resin was added. The purification process was followed by HPLC on RP-18. The chromatographic analysis of the basic fraction, after releasing from the resin by treatment with ammonia solution, highlighted the success of the purification procedure. On the other hands, ion-exchange interactions between the basic analytes and the residual acidic silanol on the surface of the stationary phase provoked poor separation and massive peak tailing. Thus, a different analytical method was developed , based on a cation-exchange analytical column, as described in a previous section, in order to improve the separation.]
CONCLUSIONS
[Based on our experiments, advantages and limitations of the employed analytical methods will be discussed.
Isolation and characterization of bioactive compounds from plant resources: the role of analysis in the ethnopharmacological approach
No full textThe phytochemical research based on ethnopharmacology is considered an effective approach in the discovery of novel chemicals entities with potential as drug leads. Plants/plant extracts/decoctions, used by folklore traditions for treating several diseases, represent a source of chemical entities but no information are available on their nature. Starting from this viewpoint, the aim of this review is to address natural-products chemists to the choice of the best methodologies, which include the combination of extraction/sample preparation tools and analytical techniques, for isolating and characterizing bioactive secondary metabolites from plants, as potential lead compounds in the drug discovery process. The work is distributed according to the different steps involved in the ethnopharmacological approach (extraction, sample preparation, biological screening etc.), discussing the analytical techniques employed for the isolation and identification of compound/s responsible for the biological activity claimed in the traditional use (separation, spectroscopic, hyphenated techniques, etc.). Particular emphasis will be on herbal medicines applications and developments achieved from 2010 up to date
Polyphenols and antioxidant activity: comparison of extraction techniques by means of principal component analysis
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Antimicrobial properties of stem bark extracts from Phyllanthus muellerianus (Kuntze) Excell
No full textAim of the study: To investigate the antimicrobial properties of Phyllanthus muellerianus (Kuntze) Excell (family Euphorbiaceae) stem bark used in Cameroon by pygmies Baka as a remedy for wound healing and tetanus.
Materials and methods: Aqueous and methanol extracts with and without defatting treatment, were prepared and their activity against Clostridium sporogenes ATCC 3584, Staphylococcus aureus ATCC 6538, Streptococcus mutans ATCC 25175, Streptococcus pyogenes ATCC 19615, Escherichia coli ATCC 10536, Candida albicans ATCC 10231, was evaluated on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal-fungicidal concentration (MBC-MFC) by the macrodilution method.
Results: Water extract showed a weak activity against Clostridium sporogenes ATCC 3584 (MIC 900 μg/mL) but resulted almost inactive against all the other microorganisms; the defatted methanol extract, almost inactive against Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 10536, Candida albicans ATCC 10231 exhibited a very interesting activity against the other tested micro-organisms, particularly against Clostridium sporogenes ATCC 3584 (MIC 100 μg/mL).
Conclusions: The activity against streptococci and Clostridium sporogenes ATCC 3584, showed by stem bark extracts of Phyllanthus muellerianus, traditionally used by pygmies Baka to treat wound infections and tetanus, is reported for the first time
Isolation and characterization of the alkaloid Nitidine responsible for the traditional use of Phyllanthus muellerianus (Kuntze) Excell stem bark against bacterial infections
Get PDFChemical composition and antimicrobial activity of Phyllanthus muellerianus (Kuntze) Excel essential oil
No full textEthnopharmacological relevance:Phyllanthusmuellerianus (Kuntze)Excel(family Euphorbiaceae) stem
bark isusedinCameroonbyBakapygmiesasaremedyforwoundhealingandtetanus.
Aim ofthestudy: To characterizethechemicalcompositionandtoevaluatetheantimicrobialproperties
of theessentialoiloftheplant.
Materialsandmethods: The essentialoilwasextractedfromthestembarkbydynamicheadspaceand
by hydrodistillationandcharacterizedbyGCandGC-MSanalyses.Theantimicrobialactivitywas
evaluatedonthebasisoftheminimuminhibitoryconcentration(MIC)andtheminimumbactericidal–
fungicidalconcentration(MBC–MFC)bythemicroandmacrodilutionmethods.Thefollowingbacteria
and fungiwereused: Clostridiumsporogenes ATCC 3584, Staphylococcusaureus ATCC 6538, Streptococcus
mutans ATCC 25175, Streptococcuspyogenes ATCC 19615, Escherichiacoli ATCC10536, Candidaalbicans
ATCC10231, Candidaalbicans LM 450, Trichophytonmentagrophytes LM 230, Trichophytonrubrum LM
237, Microsporumcanis LM 324.
Results: The hydrodistillationafforded0.06%(dryweightbasis)ofpaleyellowoil.Thirty-eight
compoundsrepresenting90.69%wereidentified.Themajorcomponent(36.40%)wasfoundtobe
(E)-isoelemicin,identifiedbycomparisonofits 1H-NMR experimentaldata,withliteraturedata.Theoil
showedgoodantibacterialactivityagainst ClostridiumSporogenes, StreptococcusmutansandStrepto-
coccuspyogenes with MICrangingfrom13.5to126 mg/ml.Aweakantifungalactivity(MIC250 mg/ml)
was foundagainst Trichophytonrubrum, only.
Conclusions: The antimicrobialactivityandthechemicalcompositionof Phyllanthusmuellerianus stem
bark essentialoilarereportedforthefirsttime
Application of Chromatographic Methods in the Study and the Characterization of Stem Bark Extracts from Phyllanthus muellerianus (Kuntze) Excell
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