Antimicrobial guaianolide sesquiterpenoids from leaves of the Saudi Arabian plant Anvillea garcinii.

Anvillea garcinii is a medicinal plant used in the Arab region for intestinal diseases, lungs and liver diseases, digestive problems, and as an anti-diabetic. Repeated chromatographic purifications of A. garcinii leaves led to the isolation of two undescribed guaiane sesquiterpene lactones (1-2), along with four known germacranolides (3-6). The structures of the new compounds were established using spectroscopic (1D, 2D NMR) and spectrometric methods (ESIMS). Compounds 1 and 2 were shown to possess hydroxyl substituents at position 9, a structural feature rarely reported in guaianolide-type sesquiterpenes. The antimicrobial activity of 1-6 was screened against five different gram-positive/negative bacteria and the fungi Candida albicans and C. parapsilosis. Compounds 1 and 2 displayed remarkable antifungal effect against C. albicans and C. parapsilosis and potent antibacterial activities against Staphylococcus aureus.

GC quantitative analysis of benzyl isothiocyanate in Salvadora persica roots extract and dental care herbal products.

An accurate, sensitive, precise and simple method was developed utilizing Gas Chromatography for the quantitative analysis of benzyl isothicyanate in Siwak extract and dental care herbal products claimed to contain Siwak. Rtx (30.0 m × 0.25 mm ID, 25 µm thickness) column was used and helium as carrier gas at a flow rate of 0.74 mL/min. The retention time of standard benzyl isothicyanate was 13.470 min under the described conditions. Linear regression data analysis indicated a good linear relationship between peak height measurement and concentration of benzyl isothiocyanate in the range of 10-50 µg/ml (R2 = 0.9971). The regression equation was y = 11,471x. The developed GC method was subjected to validation requirements set by the ICH for precision, accuracy, and robustness. The entitled GC analyses expected to be valuable for the determination of benzyl isothiocyanate in Siwak extracts and other formulations containing Siwak extract. The amount of benzyl isothiocyanate reflects the efficacy of the products.

Hepatoprotective and cytotoxic activities of Anvillea garcinii and isolation of four new secondary metabolites.

Anvillea garcinii is a medicinal plant traditionally used for the treatment of dysentery, gastrointestinal troubles, hepatitis, lung disease, colds, digestive problems and pulmonary affections and in liver diseases. Four new sesquiterpene lactones, garcinamines A-D, along with seven known compounds, were isolated from the leaves of A. garcinii. This is the first report of the isolation of amino acid analogues of parthenolide-type sesquiterpene lactones from the family Asteraceae. Total ethanol extract of leaves as well as the chloroform and n-butanol fractions were tested for their hepatoprotective effect using the carbon tetrachloride liver toxicity model. The chloroform fraction, at a dose of 400 mg/kg, demonstrated a significant hepatoprotective effect comparable to silymarin in all serum and tissue parameters. The cytotoxicity of all extracts and compounds were evaluated against five human cancer cell lines: MCF-7, HCT-116, HepG2, Hela and A-549. The results indicated that the chloroform and n-butanol fractions and compounds 3, 4, 7 and 8 displayed significant cytotoxic activity against these cell lines.

Quantitative Analysis of Benzyl Isothiocyanate in Salvadora persica Extract and Dental Care Herbal Formulations Using Reversed Phase C18 High-Performance Liquid Chromatography Method.

CONTEXT: Benzyl isothiocyanate is the active antimicrobial agent in Salvadora persica (siwak) widely used in Islamic countries for oral hygiene. AIMS: Quantification of benzyl isothiocyanate in the ethanol extract of S. persica and some dental care herbal formulations labeled to contain siwak. SETTINGS AND DESIGN: Simple and sensitive high-performance liquid chromatography method was designed. SUBJECTS AND METHODS: Separation was achieved on reverse phase C18 (250 mm × 4.6 mm, 5 µ) column with a mobile phase comprising acetonitrile and water (1:1). The detection was carried out at 190 nm using ultra violet-visible detector. The flow rate was kept at 1 mL/min. RESULTS: A sharp and well-defined peak was obtained at the retention time of 9.322 ± 0.3 min. Linear regression analysis data for the calibration plot showed a good linear relationship between response and concentration in the range of 0.5-500 µg/mL with a regression coefficient (r2) of 0.9977. The method was validated for accuracy, precision, robustness, and sensitivity. All the parameters examined met the current recommendations for the International Conference on Harmonization guidelines for method validation. CONCLUSIONS: The method was applied for the quantification of benzyl isothiocyanate in siwak extract, dental care powder, mouth wash, and toothpaste claimed to contain siwak. The developed method was found specific, simple, selective, and reliable for routine use in quality control analysis of different commercially available herbal care products. SUMMARY: A simple, accurate and precise method was developed for the analysis of the antimicrobial agent benzyl isothiocyanate in Salvadora persica (Siwak) extract and selected dental care herbal formulations using RP18 HPLCAmount of benzyl isothiocyanate will indicate the efficacy of Siwak productsThe method subject to ICH validation guidelines. Abbreviations used: RP18: Reversed phase C18, HPLC: High performance liquid chromatography, UV: Ultra violet, r2: regression coefficient, ICH: international conference on harmonization, TLC: Thin layer chromatography, CHCl3: Chloroform, v/v: volume/volume, RSD: Relative standard deviation, LOD: Limit of detection, LOQ: Limit of quantification.

Densitometric HPTLC method for qualitative, quantitative analysis and stability study of Coenzyme Q10 in pharmaceutical formulations utilizing normal and reversed-phase silica gel plates.

Two simple, precise and stability-indicating densitometric HPTLC method were developed and validated for qualitative and quantitative analysis of Coenzyme Q10 in pharmaceutical formulations using normal-phase (Method I) and reversed phase (Method II) silica gel TLC plates. Both methods were developed and validated with 10×20 cm glass-backed plates coated with 0.2 mm layers of either silica gel 60 F254 (E-Merck, Germany) using hexane-ethyl acetate (8.5:1.5 v/v) as developing system (Method I) or RP-18 silica gel 60 F254 (E-Merck, Germany) using methanol-acetone (4:6 v/v) as mobile phase (Method II). Both analyses were scanned with a densitometer at 282 nm. Linearity was found in the ranges 50-800 ng/spot (r(2)=0.9989) and 50-800 ng/spot (r(2)=0.9987) for Method I and Method II respectively. Stability of Coenzyme Q10 was explored by the two methods using acid, base, hydrogen peroxide, temperature and different solvents. Due to the efficiency of the method in separating Coenzyme Q10 from other ingredients including its degradation products, it can be applied for quality control, standardization of different pharmaceutical formulations and stability study.

Quantitative estimation of pulegone in Mentha longifolia growing in Saudi Arabia. Is it safe to use?

Our TLC study of the volatile oil isolated from Mentha longifolia showed a major UV active spot with higher Rf value than menthol. Based on the fact that the components of the oil from same plant differ quantitatively due to environmental conditions, the major spot was isolated using different chromatographic techniques and identified by spectroscopic means as pulegone. The presence of pulegone in M. longifolia, a plant widely used in Saudi Arabia, raised a hot debate due to its known toxicity. The Scientific Committee on Food, Health & Consumer Protection Directorate General, European Commission set a limit for the presence of pulegone in foodstuffs and beverages. In this paper we attempted to determine the exact amount of pulegone in different extracts, volatile oil as well as tea flavoured with M. longifolia (Habak) by densitometric HPTLC validated methods using normal phase (Method I) and reverse phase (Method II) TLC plates. The study indicated that the style of use of Habak in Saudi Arabia resulted in much less amount of pulegone than the allowed limit.

Antioxidant study of flavonoid derivatives from the aerial parts of Rhus natalensis growing in Saudi Arabia.

Phytochemical study of the CH(2)Cl(2) soluble fraction of the aerial parts of R. natalensis resulted in the isolation and identification of six flavonoid derivatives, ß-amyrin and ß-sitosterol glucoside (daucosterol). The isolated compounds were identified utilizing physical, chemical and different spectral methods including UV, 1D- 2D-NMR and MS. The compounds were identified as four flavanones; 7-O-methyl hesperetin (1), 7-O-methyl naringenin (4), (-)-homoeriodictyol (eriodictyonone) (5), eriodictyol-7-methyl ether (6) and two flavones; 7-O-methyl isokaemferide (2) and genkwanin (3). The isolated compounds as well as some available standards representing structurally similar flavones and flavanones were used to study their antioxidant potential using DPPH and try to explore the impact of structures on the antioxidant activity. In other assays flavanones were less active than flavones as antioxidant due to lack of the C-4 carbonyl group in conjugation with 2,3-double bond. However, in DPPH assay based on the ability of molecules to donate hydrogen flavanones were found more active than flavones.

Isolation of flavonoids from Delonix elata and determination of its rutin content using capillary electrophoresis.

Delonix elata (L.) Gamble (Fabaceae) is an important, traditionally used plant in Saudi Arabia. It is used to relieve rheumatic pain, flatulence and the seeds are employed as purgatives. The aim of the present study was to isolate chemical constituents of the n-butanol fraction (BF) of D. elata and to find out, by capillary electrophoresis (CE), percentage of rutin present in this BF. Three quercetin glycosides and one kaempferol rutinoside were isolated from the BF of aerial parts of D. elata; namely, Quercetin 3-O-rutinoside-7-O-glucoside (1), Quercetin 3,7-diglucoside (2), Quercetin 3-O-rutinoside (RUT) (3) and Kaempferol 3-O-rutinoside (4). Rutin, an active constituent has been reported to possess good pharmacological as well as therapeutic potentials. A sensitive and rapid procedure for quantitative determination of RUT by capillary electrophoresis was developed and its content was found to be 7.349 mg/gm, relative to n-butanol fraction and 18.373 mg%, relative to the dry powder of D. elata. The method could be recommended for approval and use in the pharmaceutical and food industries.

Phytochemical and biological evaluation of Buddleja polystachya growing in Saudi Arabia.

Several Buddleja species were the target of phytochemical and biological studies; however, nothing was reported concerning the chemistry of Buddleja polystachya Fresen. growing in Saudi Arabia. Sixteen constituents were isolated from the aerial parts of B. polystachya using various chromatographic techniques and were identified by the help of different spectral techniques including 1D, 2D NMR and mass spectrometry. Moreover, the different fractions were evaluated for their anti-inflammatory and hypoglycemic activities. The isobenzofuranone derivative (4-hydroxy-7-methylisobenzofuranone) (4), has been isolated for the first time from this natural source, B. polystachya, along with fifteen known compounds namely; phenolic fatty acid ester, 1'(4-hydroxyphenyl) ethanol ester of docosanoic (1), uvaol (2), sakuranetin (3), kumatakenin (5), cirsimaritin (6), 5-hydroxy-3,7,4'-trimethoxyflavone (7), oleanolic acid (8), herbacetin 3,7,8-trimethyl ether (9), ursolic acid (10), verbascoside (11), linarin (12), luteolin 7-O-ß-D-glucoside (13), luteolin 7-(6"-caffeoyl)-O-ß-D-glucopyranoside (14), luteolin (15), and 6-O-α-L-(4''-O-trans-cinnamoyl) rhamnopyranosylcatalpol (16). Regarding the biological activities investigated, the ethyl acetate fraction showed the most significant anti-inflammatory activity, followed by the n-butanol and the aqueous fractions. As for the petroleum ether and dichloromethane fractions, their anti-inflammatory effects were moderate. The highest hypoglycemic activity was possessed by the ethyl acetate fraction, followed by the dichloromethane fraction and the n-butanol fraction showed the weakest activity.

Phytochemical and pharmacological study of Ficus palmata growing in Saudi Arabia.

Phytochemical study of the aerial parts of Ficus palmata utilizing liquid-liquid fractionation and different chromatographic techniques resulted in the isolation of a new isomer of psoralenoside namely, trans-psoralenoside (5) in addition to, one triterpene: germanicol acetate (1), two furanocoumarins: psoralene (2), bergapten (3), one aromatic acid vanillic acid (4) and the flavone glycoside rutin (6). Structures of the isolated compounds were established through physical, 1D- and 2D-NMR and MS data. The total extract and fractions of the plant were examined in vivo for its possible effects as hepatoprotective, nephroprotective, antiulcer and anticoagulant activities in comparison with standard drugs. Hepatoprotective activity was assessed via serum biochemical parameters including aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transpeptidase (GGT), alkaline phosphatase (ALP) and total bilirubin. Tissue parameters such as non-protein sulfhydryl groups (NP-SH), malonaldehyde (MDA) and total protein (TP) were also measured. In addition to tissue parameters, nephroprotective effect was evaluated by measuring the serum levels of sodium, potassium, creatinine and urea. Histopathological study for both liver and kidney cells was also conducted. Antiulcer activity was explored by observing stomach lesions after treatment with ethanol. Whole blood clotting time (CT) was taken as a measure for the anticoagulant activity of the extract. Antioxidant activity of the total extract and fractions of the plant was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and ascorbic acid as standard.

Phytochemical and pharmacological study of Ficus cordata growing in Saudi Arabia.

Phytochemical study of the aerial parts of Ficus cordata utilizing liquid-liquid fractionation and different chromatographic techniques resulted in the isolation of four furanocoumarins: psoralene (1), hydroxy isoimperatorin (2), oxypeucedanin hydrate (3) and dorsteniol (4), the flavone glycoside rutin (5), b-sitosterol and sucrose. Structures of the isolated compounds were established through physical, 1D- and 2D-NMR and MS data. The total extract of the plant was examined in vivo for its possible effects as hepatoprotective, nephroprotective, antiulcer and anticoagulant in comparison with standard drugs. Hepatoprotective activitys were accessed via serum biochemical parameters including aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transpeptidase (GGT), alkaline phosphatase (ALP) and total bilirubin. Tissue parameters such as non-protein sulfhydryl groups (NP-SH), malonaldehyde (MDA) and total protein (TP) were also measured. In addition to tissue parameters, nephroprotective effect was evaluated by measuring the serum levels of sodium, potassium, creatinine and urea. Histopathological study for both liver and kidney cells was also conducted. Antiulcer activity was explored by observing stomach lesions after treatment with ethanol. Whole blood clotting time (CT) was taken as measure for the anticoagulant activity of the extract. All the studied parameters indicated that the total extract of Ficus cordata at 500mg/kg possess moderate hepatoprotective effect, good protection against ethanol induced ulcer and weak nephroprotective effect. The CT was about one quarter of that of warfarin.

Study of the hepatoprotective effect of Juniperus phoenicea constituents.

Different fraction obtained from the aerial parts of Juniperus phoenicea showed significant activity as hepatoprotective when investigated against carbon tetrachloride induced liver injury. The hepatoprotective activity was evaluated through the quantification of biochemical parameters and confirmed using histopathology study. Phytochemical investigation of the petroleum ether, chloroform and methanol fractions utilizing different chromatographic techniques resulted in the isolation of five known diterpenoids namely: 13-epicupressic acid (1), imbricatolic acid (2), 7α-hydroxysandaracopimaric acid (3), 3ß-hydroxysandaracopimaric acid (4), isopimaric acid (5), four flavonoid derivatives: cupressuflavone (6), hinokiflavone (7), hypolaetin-7-O-ß-xylopyranoside (9), (-) catechin (10), inaddition to sucrose (8). Both physical and spectral data were used for structure determination and all isolates were evaluated for their hepatoprotective activity. Compounds 2 and 6 were effective, however; 7 was the most active. Hepatoprotective activity of 7 is comparable with the standard drug silymarin in reducing the elevated liver enzymes and restoring normal appearance of hepatocytes. Hepatoprotective effect of combination of 6, 7 and silymarin with the diterpene sugiol was also explored.

Terpenoids from Juniperus procera with hepatoprotective activity.

The petroleum ether fraction of Juniperus procera showed significant activity as hepatoprotective when investigated against carbon tetrachloride induced liver injury. The hepatoprotective activity was evaluated through the quantification of biochemical parameters and confirmed using histopathology analysis. Phytochemical investigation of the petroleum ether fraction utilizing different chromatographic techniques resulted in the isolation of six known diterpenoids namely: 4-epi-abietol (1), ferruginol (2), hinokiol (3), sugiol (4), Z-communic acid (5) and hinokiol-1-one 3ß,12-dihydroxyabieta-8,11,13-triene-1-one) (6), in addition to the sesquiterpene 8α-acetoxyelemol (7). Both physical and spectral data were used for structure determination and all isolates were evaluated for their hepatoprotective activity. Compounds 1 and 4 were the most effective in reducing the elevated liver enzymes as indication for liver protection.

Hepatoprotective constituents from Cleome droserifolia.

The effect of ethanol extract from aerial parts of Cleome droserifolia was investigated against carbon tetrachloride induced liver injury. The hepatoprotective activity was evaluated through the quantification of biochemical parameters and confirmed using histopathology analysis. Efficient hepatoprotective effect was achieved by crude extract, fractions and some pure compounds. The phytochemical studies showed that the petroleum ether fraction afforded two known guaiane sesquiterpenes buchariol (1) and teucladiol (2) in addition to daucosterol (beta-sitosterol glucoside) (3). The CHCl(3) fraction afforded three known flavonoid derivatives; 5,3'-dihydroxy-3,6,7,4',5'-pentamethoxyflavone (4), 5'-hydroxy-3,6,7,3',4',5'-hexamethoxyflavone (5) and luteolin (6) and a known dolabellane diterpene (1R,2R,3E,7E,11R,12S)-2-O-acetyl-16-O-(3-hydroxy-3-methylglutaryl)-dolabella-3,7-dien-2,16,18-triol (7). The active parts of the MeOH fraction afforded the previously unreported 3'-methoxy-3,5,4'-trihydroxy flavone-7-neohesperidoside (8) and a known megastigmane norterpene; (6S,9R)-roseoside (9).