Antimutagenic activity of phenylpropanoids from clove (Syzygium aromaticum)

A new herbal anesthetic agent for common carp (Cyprinus carpio) sedation and anesthesia: nutmeg (Myristica fragrans) essential oil

In aquaculture, interest in natural essential oils is increasing alongside synthetic anesthetic agents. In this context, the anesthetic efficacy of nutmeg essential oil, which had not been previously tested, was investigated in common carp (Cyprinus carpio). The study, conducted using three different concentrations (800 μL/L "LC", 1,200 μL/L "MC", and 1,400 μL/L "HC"), found that induction times were <3 min for MC and HC, while LC had a longer induction time, exceeding acceptable levels. Within the first 4 h, white blood cells, red blood cells, hemoglobin, and hematocrit levels increased to >5 103/μL, >1 106/μL, >6 g/dL, and >12%, respectively. However, they returned to control levels after 8 h. Histological signs were more severe with higher concentrations, and necrosis was only observed in the HC group. Alkaline comet assay results showed DNA migration only in the HC group. According to the PROMETHEE multi-criteria decision-making model, the LC concentration is suitable for sedation, while the MC concentration should be used for deep anesthesia. The current study demonstrates that nutmeg essential oil can be used as an alternative to commercial synthetic anesthetic agents.

Anti-inflammatory naphthoquinone-monoterpene adducts and neolignans from Eugenia caryophyllata

A phytochemical investigation on the buds of edible medicinal plant, Eugenia carvophyllata, led to the discovery of seven new compounds, caryophones A-G (1-7), along with two biogenetically-related known ones, 2-methoxy-7-methyl-1,4-naphthalenedione (8) and eugenol (9). Compounds 1-3 represent the first examples of C-5-C-1' connected naphthoquinone-monoterpene adducts with a new carbon skeleton. Compounds 4-7 are a class of novel neolignans with unusual linkage patterns, in which the C-9 position of one phenylpropene unit coupled with the aromatic core of another phenylpropene unit. The chemical structures of the new compounds were determined based on extensive spectroscopic analysis, X-ray diffraction crystallography, and quantum-chemical calculation. Among the isolates, compounds (-)-2, 3, 6, and 9 showed significant in vitro inhibitory activities against respiratory syncytial virus (RSV)-induced nitric oxide (NO) production in RAW264.7 cells.

Clove Buds Volatile Compounds: Inhibitory Activity on Mycobacterium Growth and Molecular Docking on Mmr Efflux Pump Drug Resistance

Syzygium aromaticum is used in traditional and modern medicine for its various and outstanding pharmacological properties. Here, we studied the chemical composition of hexane extract and non-polar fractions (NPF) obtained from the maceration and fractionation of clove buds, in order to evaluate their in vitro antimycobacterial activity, as well as their contribution against efflux pump (EP) resistance through molecular docking experiments. The gas chromatography-mass spectrometry (GC-MS) analysis of the volatile profiles revealed the presence of eugenol, followed by eugenyl acetate, and β-caryophyllene as common major compounds. According to Resazurin microtiter assay (REMA), Mycobacterium tuberculosis H37 Rv strain was sensitive to all volatile samples at concentration range between 10 and 100 μg/mL. The NPF of ethanol extract was the best inhibitor with a MIC=10 μg/mL. The in silico study revealed a strong binding affinity between eugenol and Mmr EP protein (-8.1 Kcal/mol), involving two binding modes of hydrogen bond and π-alkyl interactions. The non-polarity character of clove volatile constituents, and their potential additive or synergistic effects could be responsible for the antimycobacterial activity. In addition, these findings suggest the benefic effect of eugenol in the management of mycobacterium drug resistance, whether as potential inhibitor of Mmr drug EP, or modulator during combination therapy.

Chemical Synthesis Enables the Configurational Determination of Myristriol, a Highly Oxygenated Phenylpropanoid from Myristica fragrans Houtt

A new phenylpropanoid, myristriol (1), along with 11 known ones were isolated from the seed kernel of Myristica fragrans Houtt. Their chemical structures were clearly elucidated by extensive spectroscopic analysis. In which, the relative configuration of 1 was finally determined as erythro-1 by comparison the NMR data of two synthetic erythro- and threo-diastereoisomers with that of natural 1.

Racemic norneolignans from the resin of Ferula sinkiangensis and their COX-2 inhibitory activity

Five new norneolignans sinkianlignans G-K (1-5), one phenolic compound ferulagenol A (6) and seven known compounds (7-13) were isolated from Ferula sinkiangensis. All the norneolignans were racemic mixtures, and chiral HPLC was used to further separate them. Their structures were assigned, including absolute configurations, using spectroscopic and computational methods. Biological evaluation showed that compounds 1-9 had significant COX-2 inhibitory activity with IC₅₀ values ranging from 3.00 μM to 23.19 μM.

Syzysamalactone, an Unusual 11-Carbon δ-Lactone Derivative from the Fresh Ripe Fruits of Syzygium samarangense (Wax Apple)

To study the chemical constituents from the ripe fresh fruits of Syzygium samarangense (wax apple) and their potential health effects, a phytochemical investigation was undertaken. A new δ-lactone derivative, syzysamalactone (1), along with a known biogenetically related δ-lactone derivative, 6-pentyl-α-pyrone (2), were isolated from the fresh ripe fruits of S. samarangense. Syzysamalactone (1) is an unusual 11-carbon δ-lactone derivative, and its chemical structure and absolute configuration were elucidated by spectroscopic data analysis. A plausible biogenetic pathway for 1 was also proposed. Furthermore, the potential neuroprotective effects of compounds 1 and 2 were assessed. As a result, compounds 1 and 2 displayed notable neuroprotective effects with EC₅₀ values of 0.29 ± 0.03 and 1.28 ± 0.06 μM, respectively, using the SH-SY5Y human neuroblastoma cell line. This is the first report of δ-lactone derivatives showing significant neuroprotective activities.

Isolation of secondary metabolites from Syzygium aromaticum (L.) Merr. & L.M.Perry. (cloves), and evaluation of their biological activities

Phytochemical investigation of dried flower buds of Syzygium aromaticum (L.) Merr. & L.M.Perry. (clove) led to the isolation and identification of fourteen known compounds, oleanolic acid (1), betulinic acid (2), para methyl benzoic acid (3), sabrinic acid (4) eucalyptolic acid (5), nigricin (6), 3-O-trans-para-coumaroylmaslinic acid (7), methyl maslinate (8), maslinic acid (9), 3, 4, 5-trimethoxy-3',4'-O,O-methylideneflavellagic acid (10), lantanone (11) 3,4,3'-trimethoxyellagic acid (12), 11-oxo-oleanolic acid (13), and β-sitosterol-3-O-β-D-glucopyranoside (14). Their structures were identified by ¹H NMR, ¹³C NMR, Mass spectroscopic techniques, and comparison with the literature data. Compounds 3, and 7-9 showed a strong mortality against root knot nematode, Meloidogyne incognita at 0.125% concentration after 72 hours (88-92% inhibition). Compound 4 showed a good anti-glycation activity with IC₅₀ = 142.0 ± 1.8 µM when compared with standard, i.e. rutin (IC₅₀ = 54.59 ± 2.20 µM). Compound 10 showed a comparable urease inhibitory activity (IC₅₀ = 26.1 ± 0.19 µM) with the positive control thiourea (IC₅₀ = 24.5 ± 0.34 µM).

Microwave-Assisted Extraction of Anticancer Flavonoid, 2′,4′-Dihydroxy-6′-Methoxy-3′,5′-Dimethyl Chalcone (DMC), Rich Extract from Syzygium nervosum Fruits

2′,4′-Dihydroxy-6′-methoxy-3′,5′-dimethyl chalcone (DMC) is a biological flavonoid that is present in the fruits of Syzygium nervosum (Ma-Kiang in Thai). Microwave-assisted extraction (MAE), which utilizes microwave radiation to heat the extraction solvent quickly and effectively, was used to recover DMC-rich extract from Syzygium nervosum fruit. To determine the DMC content, a highly accurate and precise HPLC technique was developed. The influences of MAE conditions, including the solid–liquid ratio, microwave power, and microwave duration on the content of DMC, were sequentially employed by a single factor investigation and response surface methodology (RSM) exploratory design. The predicted quadratic models were fitted due to their highly significant (p < 0.0001) and excellent determination coefficient (R² = 0.9944). The optimal conditions for producing DMC-rich extract were a ratio of sample to solvent of 1:35 g/mL, a microwave power of 350 W, and a microwave time of 38 min. Under the optimal MAE setting, the DMC content reached 1409 ± 24 µg/g dry sample, which was greater than that of the conventional heat reflux extraction (HRE) (1337 ± 37 µg/g dry sample) and maceration (1225 ± 81 µg/g dry sample). The DMC-rich extract obtained from MAE showed stronger anticancer activities against A549 (human lung cancer cells) and HepG2 (human liver cancer cells) than the individual DMC substance, which makes MAE an effective method for extracting essential phytochemicals from plants in the nature.

Oleuropein and Verbascoside - Their Inhibition Effects on Carbonic Anhydrase and Molecular Docking Studies

Recently, carbonic anhydrase (CA, E.C.4.2.1.1) inhibitors from natural product have paved the way for novel drug design in the treatment and prevention of some global diseases such as glaucoma, diabetes, and cancer. For this purpose, the inhibition effects of oleuropein and verbascoside from olive (Olea europaea L.) oil on human carbonic anhydrase I, and II (hCA I, and II) isoenzymes were evaluated in the current study. The inhibition effects of both natural compounds were determined by the esterase activity (in vitro). IC₅₀ value of oleuropein and verbascoside was calculated as 1.57 and 1.73 µM for hCA I isoenzyme, respectively. At the same manner, K _i values were determined as 1.25 ± 0.42 and 2.00 ± 0.42 µM, respectively. Then, IC₅₀ value of each compound for hCA II isoenzyme was calculated as 2.23 and 1.90 µM, respectively. Similarly, K _i values were determined as 2.37 ± 0.87 µM and 1.49 ± 0.33 µM, respectively. Also, the inhibitory effects and potent binding mechanisms of oleuropein and verbascoside on hCA I, and II isoenzymes were realized by molecular docking studies. Consequently, both natural phenolic compounds demonstrated the potent inhibition profiles against the both isoenzymes. Therefore, we believe that these results may break new ground in the drug development for the treatment of some global disorders.

Elaeocarpus floribundus Bl. seeds as a new source of bioactive compounds with promising antioxidant and antimicrobial properties

The fruits of Elaeocarpus floribundus Bl. (Elaeocarpaceae) are edible and are normally prescribed for treatment of diseases. The medicinal uses of the fruit create considerable quantities of seeds as wastes. In an attempt to valorise this biomass, we studied the antimicrobial and antioxidant activities of the ethanolic seed extract. The extract inhibited the growth of the tested pathogens and was also a very strong scavenger of DPPH free radicals. Consequently, the extract was phytochemically investigated and this study reports the initial isolation of five phenolic compounds from this source. The structures of the isolated compounds were elucidated by spectra analyses including HR-ESI-MS, 1D and 2D NMR experiments. The isolated compounds exhibited a wide range of antimicrobial activities against the tested pathogens. Gallic acid (4) showed the most activity against Bacillus subtilis with a minimum inhibitory concentration (MIC) value of 30 µg/mL, while the MIC values of the antimicrobial standards range between 10 and 35 µg/mL. Compound 4, crude ethanolic extract, and the ethyl acetate fraction were more a potent free radical scavenger of DPPH compared to ascorbic acid. Hence, the seeds of E. floribundus could be considered as a new source of bioactive compounds for pharmaceutical and food-related industries.

Electrospinning of Essential Oils

The extensive and sometimes unregulated use of synthetic chemicals, such as drugs, preservatives, and pesticides, is posing big threats to global health, the environment, and food security. This has stimulated the research of new strategies to deal with bacterial infections in animals and humans and to eradicate pests. Plant extracts, particularly essential oils, have recently emerged as valid alternatives to synthetic drugs, due to their properties which include antibacterial, antifungal, anti-inflammatory, antioxidant, and insecticidal activity. This review discusses the current research on the use of electrospinning to encapsulate essential oils into polymeric nanofibres and achieve controlled release of these bioactive compounds, while protecting them from degradation. The works here analysed demonstrate that the electrospinning process is an effective strategy to preserve the properties of essential oils and create bioactive membranes for biomedical, pharmaceutical, and food packaging applications.

L, Cacciola F, Lakhssassi N. Development of a Millet Starch Edible Film Containing Clove Essential Oil

Medicinal plants contain various secondary metabolites. The present study analyzed the essential oil of buds from clove (Syzygium aromaticum L.; Family: Myrtaceae) using gas chromatography-mass spectrometry (GC-MS). GC-MS analysis showed the presence of six major phytoconstituents, such as eugenol (66.01%), caryophyllene (19.88%), caryophyllene oxide (5.80%), phenol, 2-methoxy-4-(2-propenyl)-acetate (4.55%), and humulene (3.75%). The effect of clove essential oils (CEO) at 0%, 1%, 2%, and 3% (w/w) on the mechanical and barrier properties of starch films was evaluated. The tensile strength (TS) and elongation (E) of films with clove essential oil were 6.25 ± 0.03 MPa and 5.67% ± 0.08%, respectively. The antioxidant activity of the films significantly increased the millet starch film and presented the lowest antioxidant activity (0.3%) at a 30 minute incubation for the control sample, while increasing CEO fraction in the starch film lead to an increase in antioxidant activity, and the 3% CEO combined film presented the highest antioxidant activity (15.96%) at 90 min incubation. This finding could be explained by the incorporation of clove oil containing antioxidant properties that significantly increased with the incorporation of CEO (p < 0.05). A zone of inhibition ranging from 16 to 27 mm in diameter was obtained when using a concentration of CEO ranging from 1% to 3%. We also observed the presence of an antimicrobial activity on several tested microorganism including Escherichia coli, Pseudomonas aeruginosa, Enterobacter sp, Bacillus cereus, Staphylococcus aureus, and Trichoderma fungi. Thus, the current study reveals the possibility of using a millet starch edible film as a preservation method.

Biochemical characterization, anti-inflammatory properties and ulcerogenic traits of some cold-pressed oils in experimental animals

CONTEXT

Cold-pressed oils (CPO) are commercially available in the market and characterized by their health-promoting properties.

OBJECTIVE

Clove oil (CLO), coriander seed oil (COO) and black cumin oil (BCO) were evaluated for their bioactive lipids. Pharmacological screening was performed to evaluate acute toxicity, anti-inflammatory and ulcerogenic effects as well as histopathological changes in tissues of albino rats fed with CPO.

MATERIALS AND METHODS

Fatty acids, tocols and total phenolics were analyzed. The acute toxicity test for each CPO was estimated during 14 d. Carrageenan-induced rat paw oedema was used for assessment of anti-inflammatory activity of CPO. Animals were fasted overnight, and via oral gavage given indomethacin (10 mg/kg) or CPO (400 mg/kg) to investigate ulcerogenecity. Histopathological changes in liver, kidney, heart, spleen and stomach were screened.

RESULTS

Amounts of α-, β-, γ- and δ-tocopherols in CLO were 1495, 58, 4177 and 177 mg/kg oil, respectively. In COO, α, β, γ and δ-tocopherols were 10.0, 18.2, 5.1 and 34.8%, respectively. In BCO, β-tocotrienol was the main constituent. CLO, COO and BCO contained 4.6, 4.2 and 3.6 mg GAE/g, respectively. Acute toxicity test determined that 400 mg/kg of CPO to be used. In the carrageenan model of inflammation, pretreatment of rats with indomethacin (10 mg/kg) or CLO (400 mg/kg) induced a significant (p < 0.05) reduction by 31.3 and 27.4%, respectively, in rat paw oedema as compared with the carrageenan-treated group. Indomethacin induced a significant ulcerogenic effect with an ulcer index of 19. Oral treatment of CPO showed no ulcerogenic effect, wherein no histopathological changes were observed.

CONCLUSIONS

CPO, particularly CLO, could minimize acute inflammation.

Antitrypanosomal activity and evaluation of the mechanism of action of dehydrodieugenol isolated from Nectandra leucantha (Lauraceae) and its methylated derivative against Trypanosoma cruzi

BACKGROUND

From a previous screening of Brazilian biodiversity for antiprotozoal activity, the hexane extract from leaves of Nectandra leucantha (Nees & Mart.) (Lauraceae) demonstrated activity against Trypanosoma cruzi. Chromatographic separation of this extract afforded bioactive dehydrodieugenol (1). Furthermore, methylated derivative 2 (dehydrodieugenol dimethyl ether) was prepared and also tested against T. cruzi.

PURPOSE

To examine the therapeutical potential of compounds 1 and 2 against T. cruzi as well as to elucidate the mechanism of action of bioactive compound 1 against T. cruzi.

METHODS/STUDY DESIGN

Crude hexane extract from leaves was subjected to chromatographic steps to afford bioactive compound 1. In order to analyze the effect of additional methyl group in the antiparasitic activity of 1, derivative 2 was prepared (both are no pan-assay interference compounds - PAINS). These compounds were evaluated in vitro against T. cruzi (trypomastigote and amastigote forms) and analyzed for the potential effect in host cells through the production of nitric oxide and reactive oxygen species. Finally, the plasma membrane effect of the most potent compound 1 was investigated in T. cruzi trypomastigotes.

RESULTS

Compounds 1 and 2 displayed activity against amastigotes of T. cruzi. Although both compounds promoted activity against intracellular amastigotes, the production of nitric oxide and reactive oxygen species of host cells were unaltered, suggesting an antiparasitic activity other than host cell activation. Considering 1 the most effective compound against T. cruzi, the interference in the plasma membrane of the trypomastigotes was investigated using the fluorescent probe SYTOX^® Green. After a short-term incubation, the fluidity and integrity of the plasma membrane was completely altered, suggesting it as a primary target for compound 1 in T. cruzi.

CONCLUSION

Compounds 1 and 2 selectively eliminated the intracellular parasites without host cell activation and could be important scaffolds for the search of new hit compounds.

Effects of clove essential oil and eugenol on quality and browning control of fresh-cut lettuce

This study confirmed the inhibitory effects of clove essential oil (CEO) and eugenol (EUG) on the browning and relevant enzymes of fresh-cut lettuce, and examined associated mechanisms by inhibition kinetics and computational docking analysis. Fresh-cut lettuce was treated with 0.05% CEO and 0.05% EUG solutions, resulting in inhibition of the deterioration of texture quality and browning of the lettuce surface and interior. Compared with the controls, CEO and EUG significantly inhibited the activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO), and peroxidase (POD, all p<0.05). EUG suppressed PAL, PPO, and POD in vitro in a dose-dependent manner, with IC50 values of 5.4±0.9, 29.5±3.5, and 61.9±6.7mM, respectively. The binding and inhibition effects of EUG on PAL, PPO, and POD, determined by inhibition kinetics and computational docking analysis, established EUG as a competitive inhibitor of these browning-relevant enzymes.

Hepatoprotective effect of cold-pressed Syzygium aromaticum oil against carbon tetrachloride (CCl4)-induced hepatotoxicity in rats

Contexts: Exposure to environmental pollutants such as carbon tetrachloride (CCl4) causes liver injuries. There are claims that extracts from Syzygium aromaticum (Linn.) Merrill & L.M.Perry, (Myrtaceae) protects from such injuries.

OBJECTIVE

This study investigates the protective effects of cold-pressed S. aromaticum oil (CO) against CCl4-induced liver toxicity in rats.

MATERIALS AND METHODS

CO was orally administered to rats in two doses (100 and 200 mg/kg) along with CCl4 (1 mL/kg in olive oil) for 8 weeks. Indices of liver and kidney functions, lipid profile, and peroxidation were evaluated in rats' serum and tissues. Fatty acids and bioactive lipids of CO were analyzed.

RESULTS

High levels of monounsaturated fatty acids (39.7%) and polyunsaturated fatty acids (42.1%) were detected in CO. The oil contained high amounts of tocols and phenolics. The LD50 value at 24 h was approximately 5950 mg/kg. Treatment with 200 mg/kg CO resulted in a decrease of creatinine, urea, and uric acid levels to 0.86, 32.6, and 2.99 mg/dL, respectively. Levels of TL, TC, TAG, LDL-C, and VLDL-C were decreased to 167, 195.3, 584.5, 74.6, and 39.0 mg/L, respectively, after 8 weeks of treatment. Hepatic malondialdehyde levels were reduced and glutathione levels were elevated in CO-treated rats. CO reduced the activities of AST, ALT, and ALP as well as kidney function markers, protein, and lipid profiles, respectively. Histopathological examination of liver indicated that CO treatment reduced fatty degenerations, cytoplasmic vacuolization, and necrosis.

CONCLUSION

CO possessed a protective effect against CCl4-induced hepatotoxicity in rats, mediated possibly by the antioxidant properties of the oil.

Synthesis and Antileishmanial Activity of Natural Dehydrodieugenol and Its Mono- and Dimethyl Ethers

The study of chemistry of naturally occurring compounds and the synthesis of their derivatives is fundamentally important for the development of new drugs. In this work, dehydrodieugenol (DHDE) was obtained through oxidative coupling of eugenol, promoted by an aqueous mixture of potassium ferricyanide (K3 [Fe(CN)6 ]) and NH3  · H2 O. The partial methoxylation of DHDE with MeI and K2 CO3 mainly resulted in the molecular-shaped monomethyl ether (DHDE-1MeO) and its dimethyl ether derivative (DHDE-2MeO). The products from the reactions were characterized by (1) H- and (13) C-NMR spectroscopy. Additionally, these studies have reported the antileishmanial activity of DHDE against Leishmania amazonensis (IC50 value of 42.20 μg ml(-1) ) and shown that partial methoxylation of DHDE results in a significant increase in its antiparasitic activity (IC50 value of 13.68 μg ml(-1) ). Based on in vitro bioassays, DHDE-1MeO has shown the highest leishmanicidal activity in promastigota form. Production by direct one-step synthesis of this monomethoxylated compound can be considered to be a cost-effective and environmentally friendly method with a short reaction time.

Two new secoiridoids and other anti-hepatitis B virus active constituents from Swertia patens

Two new secoiridoids, swerpatic acid (1) with an unusual C8 skeleton and swerpalactone (2), were isolated along with ten known compounds (3-12) from the whole plants of Swertia patens. Their structures were elucidated by comprehensive spectroscopic analyses. Eight compounds were evaluated for their anti-hepatitis B virus (HBV) activities on Hep G 2.2.15 cell line in vitro. Compounds 4 and 10 showed moderate inhibitory activities on the secretion of HBsAg with IC50 values of 1.96 and 0.50 mM.

Isolation, Characterization, Crystal Structure Elucidation of Two Flavanones and Simultaneous RP-HPLC Determination of Five Major Compounds from Syzygium campanulatum Korth

Two flavanones named (2S)-7-Hydroxy-5-methoxy-6,8-dimethyl flavanone (1), (S)-5,7-dihydroxy-6,8-dimethyl-flavanone (2), along with known chalcone, namely, (E)-2ʹ,4ʹ-dihydroxy-6ʹ-methoxy-3ʹ,5ʹ-dimethylchalcone (3) and two triterpenoids, namely, betulinic and ursolic acids (4 and 5), were isolated from the leaves of Syzygium campanulatum Korth (Myrtaceae). The structures of compounds (1 and 2) were determined on the basis of UV-visible, FTIR, NMR spectroscopies and LC-EIMS analytical techniques. Furthermore, new, simple, precise, selective, accurate, highly sensitive, efficient and reproducible RP-HPLC method was developed and validated for the quantitative analysis of the compounds (1–5) from S. campanulatum plants of five different age. RP-HPLC method was validated in terms of specificity, linearity (r² ≤ 0.999), precision (2.0% RSD), and recoveries (94.4%–105%). The LOD and LOQ of these compounds ranged from 0.13–0.38 and 0.10–2.23 µg·mL⁻¹, respectively. Anti-proliferative activity of isolated flavanones (1 and 2) and standardized extract of S. campanulatum was evaluated on human colon cancer (HCT 116) cell line. Compounds (1 and 2) and extract revealed potent and dose-dependent activity with IC₅₀ 67.6, 132.9 and 93.4 µg·mL⁻¹, respectively. To the best of our knowledge, this is the first study on isolation, characterization, X-ray crystallographic analysis of compounds (1 and 2) and simultaneous RP-HPLC determination of five major compounds (1–5) from different age of S. campanulatum plants.

Eugenol-rich Fraction of Syzygium aromaticum (Clove) Reverses Biochemical and Histopathological Changes in Liver Cirrhosis and Inhibits Hepatic Cell Proliferation

Background:

Dried flower bud of Syzygium aromaticum (clove) is rich in eugenol, an antioxidant and antiinflammatory compound that can protect liver against injury. Clove, besides eugenol, also contains other pharmacologically active phytochemicals such as β-sitosterol and ascorbic acid. This study reports the effect of eugenol-rich fraction (ERF) of clove on liver cirrhosis induced by thioacetamide.

Methods:

Cirrhosis of the liver, which predisposes to hepatocellular carcinoma, was induced by administering thioacetamide (0.03%) in drinking water for 16 weeks. Cirrhotic animals were divided into two groups; the treated group was administered ERF for 9 weeks, one week after discontinuation of thioacetamide, while the other group received normal saline for a similar duration of time.

Results:

The treatment with ERF, as determined by histopathology and through a battery of biochemical markers of hepatic injury, oxidative stress and drug metabolizing enzymes, significantly ameliorated the signs of liver cirrhosis. It lowered the elevated levels of alkaline phosphatase, γ-glutamyl transferase and other biochemical changes in liver cirrhosis. Histopathology of the liver corroborated the effect of ERF with biochemical findings. ERF treatment further inhibited cell proliferation, as demonstrated by reduced [³H]-thymidine uptake.

Conclusions:

Data provide evidence supporting the protective action of ERF on liver cirrhosis. The study assumes significance because cirrhosis predisposes the liver to cancer, which is characterized by abnormal cell proliferation. ERF in this study is reported to inhibit hepatic cell proliferation and at the same time decrease oxidative stress, which might be the mechanism of protection against liver cirrhosis.

Anti-bacterial and anti-oxidant activities of leaf extracts of Combretum vendae (Combretecacea) and the isolation of an anti-bacterial compound

BACKGROUND

Combretum vendae A.E. van Wyk (Combretaceae) is used for the treatment of bacterial related infections and oxidative related diseases by indigenous people of South Africa. Dried leaves extracts of C. vendae were investigated for bioactivity against a variety of bacterial strains and their antioxidant potential evaluated.

MATERIALS AND METHODS

Constituents of leaf material were serially extracted using solvents of varying polarities, TLC chromatograms of the fractions were sprayed with 2,2 diphenyl-1-picrylhydrazyl (DPPH) to determine the presence of antioxidant compounds. Bio-autography was used to determine the number of antibacterial compounds active against Staphylococcus aureus, Enterococcus faecalis, Eschericha coli and Pseudomonas aeruginosa. Minimum inhibitory concentration (MIC) values were determined using serial microplate dilution method. The chloroform fraction was subjected to bio-assay guided column chromatography to isolate the active compound.

RESULTS

The mass extracted by different solvents was below 10% dry weight. MIC values for different extracts against different pathogens ranges from 0.08 to 0.64 mg/ml. The compound isolated was identified as acacetin having an Rf value of 0.28 following elution in the Ethanol: Methanol: Water [E: M: W (10: 1.35: 1 v/v). Acacetin had MIC values ranging from 0.16 to 0.35 mg/ml.

CONCLUSION

We report for the first time the isolation of acacetin as the main antibacterial compound from the leaves of Combretum vendae.

Bioactive lipids, radical scavenging potential, and antimicrobial properties of cold pressed clove (Syzygium aromaticum) oil

Health promoting cold pressed oils may improve human health and prevent certain diseases. It is hard to find any research concerning the composition and functional properties of cold pressed clove (Syzygium aromaticum) oil (CO). Cold pressed CO was evaluated for its lipid classes, fatty acid profiles, and tocol contents. In addition, antiradical and antimicrobial properties of CO were evaluated. The amounts of neutral lipids in CO was the highest (∼94.7% of total lipids), followed by glycolipids and phospholipids. The main fatty acids in CO were linoleic and oleic, which comprise together ∼80% of total fatty acids. Stearic and palmitic acids were the main saturated fatty acids. α- and γ-tocopherols and δ-tocotrienol were the main detected tocols. CO had higher antiradical action against DPPH• and galvinoxyl radicals than virgin olive oil. The results of antimicrobial properties revealed that CO inhibited the growth of all tested microorganisms. CO had a drastic effect on the biosynthesis of proteins and lipids in cells of Bacillus subtilis. In consideration of potential utilization, detailed knowledge on the composition and functional properties of CO is of major importance.

Aldose reductase inhibitory activity of compounds from Zea mays L

Aldose reductase (AR) inhibitors have a considerable therapeutic potential against diabetes complications and do not increase the risk of hypoglycemia. Through bioassay-guided fractionation of an EtOH extract of the kernel from purple corn (Zea mays L.), 7 nonanthocyanin phenolic compounds (compound 1-7) and 5 anthocyanins (compound 8-12) were isolated. These compounds were investigated by rat lens aldose reductase (RLAR) inhibitory assays. Kinetic analyses of recombinant human aldose reductase (rhAR) were performed, and intracellular galactitol levels were measured. Hirsutrin, one of 12 isolated compounds, showed the most potent RLAR inhibitory activity (IC(50), 4.78 μ M). In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/substrate concentration, hirsutrin showed competitive inhibition against rhAR. Furthermore, hirsutrin inhibited galactitol formation in rat lens and erythrocytes sample incubated with a high concentration of galactose; this finding indicates that hirsutrin may effectively prevent osmotic stress in hyperglycemia. Therefore, hirsutrin derived from Zea mays L. may be a potential therapeutic agent against diabetes complications.

Antidiabetic Potentials of a Novel Polyherbal Preparation Formulated According to Principles of Siddha System of Medicine

According to the principles of Siddha system of medicine, the following polyherbal preparation consisting of 5 plant parts in equal ratio namely, Asparagus racemosus, Emblica officinalis, Salacia oblonga, Syzygium aromaticum, and Tinospora cordifolia was formulated to treat experimental type 2 diabetic rats. So, using plants having aphrodisiac property in the formulation is a rational approach and first of its kind, as there have been no reports so far. Phenolics and other bioactive compounds present in polyherbal preparation may be responsible for lipid-lowering effects and strong antioxidant activity. Polyherbal preparation treatment reverted the activities of glycolytic and gluconeogenic enzymes that are disturbed in diabetic rats. It is concluded that polyherbal preparation treatment improves deranged lipid profile, antioxidant status, glycogen content, and decreases lipid peroxidation, which provides stability to membrane integrity and thus favors insulin receptor to achieve better glucose tolerance through a holistic approach.

Enantioselective total synthesis of (+)-galbulin via organocatalytic domino Michael-Michael-aldol condensation

A concise and practical enantioselective synthesis of (+)-galbulin has been achieved using organocatalytic domino Michael-Michael-aldol condensation and organocatalytic kinetic resolution as the key steps.

Activity and stability studies of verbascoside, a novel antioxidant, in dermo-cosmetic and pharmaceutical topical formulations

We here report the results of our investigations carried out on verbascoside, a phenylpropanoid glycoside known for its antioxidant, anti-inflammatory and photoprotective actions. Verbascoside was obtained from Buddleia davidii meristematic cells, obtained in turn using a sustainable biotechnology platform which employs an in vitro plant cell culture technology. Verbascoside was first investigated to assess the behaviour of the active ingredient in solution or in finished preparations, in view of its potential topical use, especially in skin protection. Stability studies were performed by HPLC, and a PCL assay was adopted to determine the radical scavenging activity toward superoxide anion. The high hydrophilic character of verbascoside, suggested in a somewhat limited range of possible applications, leading us to explore its derivatization to obtain the semi-synthetic derivative VPP, an acyl derivative of verbascoside, with an improved range of applications due to its lower hydrophilic profile. Alone, VPP revealed increased antioxidant activity, both as an active ingredient and in dermocosmetic preparations. Stability studies showed a greater stability of VPP in lipophilic vehicles, whereas the parent verbascoside proved more stable in an O/W emulsions. Verbascoside was also stable in suppositories, an interesting pharmaceutical form for possible applications in treatment of inflammation of the intestinal mucosa.