Phenolic composition and biological activities of Juniperus drupacea Labill. berries from Turkey

The Precious Potential of the Sacred Tree Chamaecyparis obtusa (Siebold & Zucc.) Endl. as a Source of Secondary Metabolites with Broad Biological Applications

Chamaecyparis obtusa (Siebold & Zucc.) Endl., which belongs to the Cupressaceae family, occurs naturally in North America and Asia, especially in Korea, Taiwan and Japan, where it is an evergreen, coniferous, sacred, ethnic tree. It has many useful varieties that are widespread throughout the world and grown for decorative purposes. It is most commonly used as an ornamental plant in homes, gardens or parks. It is also widely used in many areas of the economy; for example, its wood is used in architecture as well as furniture production. In addition, oil extracted from Chamaecyparis obtusa is increasingly used in cosmetology for skin care. Due to its wide economic demand, mainly in Japan, it represents the largest area of plantation forest. Despite this, it is on the red list of endangered species. Its use in ethnopharmacology has led to more and more research in recent years in an attempt to elucidate the potential mechanisms of its various biological activities, such as antimicrobial, antioxidant, anticancer, antidiabetic, antiasthmatic, anti-inflammatory, antiallergic, analgesic and central nervous system effects. It has also been shown that Chamaecyparis obtusa can be used as an insect repellent and an ingredient in plant disease treatment. This thesis provides a comprehensive review of the biological studies to date, looking at different areas of the economic fields of potential use of Chamaecyparis obtusa.

Mineral composition, the profile of phenolic compounds, organic acids, sugar and in vitro antioxidant capacity, and antimicrobial activity of organic extracts of Juniperus drupacea fruits

Juniperus drupacea fruit is widely used in traditional and complementary medicine in Turkey for the treatment of different diseases in various forms such as molasses and tar. This study was carried out to evaluate the phenolic compounds, organic acid, sugar, and macro- and micromineral distributions of methanol and water extracts of J. drupace fruit, as well as their antioxidant and antimicrobial potential. For this purpose, total phenolic content by spectrophotometer, phenolics, organic acids, and sugars distributions by HPLC in extracts of J. drupacea fruits, and macro- and micromineral element content by ICP-AES in fruit were determined. 2,2-diphenyl-l-picrylhydrazyl assay (DPPH assay) was used to evaluate in vitro antioxidant activity in extracts. The antimicrobial potential of J. drupacea fruit methanol extract against some gram-positive and gram-negative pathogenic bacteria was evaluated using disk diffusion and minimum inhibitory concentration (MIC) methods. The potassium macroelement and the iron microelement were found at high content in J. drupacea fruit. The total phenolic content in the methanol extracts was higher than the water extracts. Among the individual phenolic compounds, catechin, a flavonoid that was the highest in both extractions, was determined as 300.49 μg/g in methanol extract and 314.88 μg/g in water extract. DPPH scavenging activity was higher in methanol extracts. While the methanol extract of J. drupacea had no-inhibitory effect on the gram-negative bacteria tested, it exhibited a strong inhibition on the gram-positive bacteria Listeria innocua, Listeria monocytogenes, Staphylococcus carnosus, and Enterococcus faecalis.

(Poly)phenol intake, plant-rich dietary patterns and cardiometabolic health: a cross-sectional study

Diet is an important modifiable risk factor for cardiometabolic diseases. Plant foods contain a complex mixture of nutrients and bioactive compounds such as (poly)phenols. Plant-rich dietary patterns have been associated with reduced cardiometabolic risk in epidemiological studies. However, studies have not fully considered (poly)phenols as a mediating factor in the relationship. A cross-sectional analysis was conducted in 525 healthy participants, aged 41.6 ± 18.3 years. Volunteers completed the validated European Prospective Investigation into Diet and Cancer (EPIC) Norfolk Food Frequency Questionnaire (FFQ). We investigated the associations between plant-rich dietary patterns, (poly)phenol intake, and cardiometabolic health. Positive associations were found between (poly)phenols and higher adherence to dietary scores, except for the unhealthy Plant-based Diet Index (uPDI), which was negatively associated with (poly)phenol intake. Correlations were significant for healthy PDI (hPDI), with positive associations with proanthocyanidins (r = 0.39, p < 0.01) and flavonols (r = 0.37, p < 0.01). Among dietary scores, Dietary Approaches to Stop Hypertension (DASH) showed negative associations with diastolic blood pressure (DBP), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein cholesterol (Non-HDL-C) (stdBeta -0.12 to -0.10, p < 0.05). The Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) score was positively associated with flow-mediated dilation (FMD, stdBeta = 0.10, p = 0.02) and negatively associated with the 10-year Atherosclerotic Cardiovascular Disease (ASCVD) risk score (stdBeta = -0.12, p = 0.01). Higher intake of flavonoids, flavan-3-ols, flavan-3-ol monomers, theaflavins, and hydroxybenzoic acids (stdBeta: -0.31 to -0.29, p = 0.02) also showed a negative association with a 10-year ASCVD risk score. Flavanones showed significant associations with cardiometabolic markers such as fasting plasma glucose (FPG) (stdBeta = -0.11, p = 0.04), TC (stdBeta = -0.13, p = 0.03), and the Homeostasis Model Assessment (HOMA) of beta cell function (%B) (stdBeta = 0.18, p = 0.04). Flavanone intake was identified as a potential partial mediator in the negative association between TC and plant-rich dietary scores DASH, Original Mediterranean diet scores (O-MED), PDI, and hPDI (proportion mediated = 0.01% to 0.07%, p < 0.05). Higher (poly)phenol intake, particularly flavanone intake, is associated with higher adherence to plant-rich dietary patterns and favourable biomarkers of cardiometabolic risk indicating (poly)phenols may be mediating factors in the beneficial effects.

Interplay between the (Poly)phenol Metabolome, Gut Microbiome, and Cardiovascular Health in Women: A Cross-Sectional Study from the TwinsUK Cohort

BACKGROUND

Dietary (poly)phenol consumption is inversely associated with cardiovascular disease (CVD) risk in epidemiological studies, but little is known about the role of the gut microbiome in this relationship.

METHODS

In 200 healthy females, aged 62.0 ± 10.0 years, from the TwinsUK cohort, 114 individual (poly)phenol metabolites were measured from spot urine using ultra-high-performance liquid chromatography-mass spectrometry. The associations between metabolites, the gut microbiome (alpha diversity and genera), and cardiovascular scores were investigated using linear mixed models adjusting age, BMI, fibre, energy intake, family relatedness, and multiple testing (FDR < 0.1).

RESULTS

Significant associations were found between phenolic acid metabolites, CVD risk, and the gut microbiome. A total of 35 phenolic acid metabolites were associated with the Firmicutes phylum, while 5 metabolites were associated with alpha diversity (FDR-adjusted p < 0.05). Negative associations were observed between the atherosclerotic CVD (ASCVD) risk score and five phenolic acid metabolites, two tyrosol metabolites, and daidzein with stdBeta (95% (CI)) ranging from -0.05 (-0.09, -0.01) for 3-(2,4-dihydroxyphenyl)propanoic acid to -0.04 (-0.08, -0.003) for 2-hydroxycinnamic acid (FDR-adjusted p < 0.1). The genus 5-7N15 in the Bacteroidetes phylum was positively associated with the same metabolites, including 3-(3,5-dihydroxyphenyl)propanoic acid, 3-(2,4-dihydroxyphenyl)propanoic acid, 3-(3,4-dihydroxyphenyl)propanoic acid), 3-hydroxyphenylethanol-4-sulfate, and 4-hydroxyphenylethanol-3-sulfate)(stdBeta (95% CI): 0.23 (0.09, 0.36) to 0.28 (0.15, 0.42), FDR-adjusted p < 0.05), and negatively associated with the ASCVD score (stdBeta (95% CI): -0.05 (-0.09, -0.01), FDR-adjusted p = 0.02). Mediation analysis showed that genus 5-7N15 mediated 23.8% of the total effect of 3-(3,4-dihydroxyphenyl)propanoic acid on the ASCVD score.

CONCLUSIONS

Coffee, tea, red wine, and several vegetables and fruits, especially berries, are the most abundant food sources of phenolic acids that have the strongest associations with CVD risk. We found that the gut microbiome, particularly the genus 5-7N15, partially mediates the negative association between urinary (poly)phenols and cardiovascular risk, supporting a key role of the gut microbiome in the health benefits of dietary (poly)phenols.

Comparison between dietary assessment methods and biomarkers in estimating dietary (poly)phenol intake

Background: although widely used, there is limited understanding of the suitability of different dietary assessment tools to estimate (poly)phenol intake. This study aims to compare the agreement between a food frequency questionnaire (FFQ) and a 7-day food diary (7DD) in assessing (poly)phenol intake and explore their associations with the urinary and plasma (poly)phenol metabolites. Methods: healthy free-living participants aged 18-80 years (n = 413) completed a 7DD and an FFQ (EPIC-Norfolk) and provided a 24 h urine and a fasting plasma sample. A comprehensive in-house (poly)phenol database was used to estimate (poly)phenol intake. The phenolic metabolite levels were analysed using a validated LC-MS method. The agreement between dietary assessment methods and biomarkers were evaluated by intraclass correlation coefficients (ICC), weighted kappa, quartile classification, Bland-Altman plots and correlations. Results: the total (poly)phenol intake estimated from FFQ was higher than from 7DD (median 1463 and 1042 mg d^-1, respectively). The agreement between FFQ and 7DD were moderate (ICC 0.51-0.59) for total (poly)phenols, flavan-3-ols, total phenolic acids, hydroxycinnamic acids and alkylmethoxyphenols, and were poor for all the other classes and subclasses (ICC 0.00-0.48). Positive correlations with total urine phenolic metabolites were found in FFQ estimated anthocyanins, dihydroflavonols, total lignans, tyrosols, alkylmethoxyphenols, total phenolic acids, and total stilbenes and the 7DD estimated theaflavins and thearubigins (all FDR adjusted p values < 0.1). No significant correlations were found between total plasma phenolic metabolites and (poly)phenol intake. Conclusion: agreements between dietary assessment tools were moderate for the major classes of (poly)phenols, while agreements between (poly)phenol intake and biomarkers were poor. Future research using biomarker approaches to increase the accuracy of estimating (poly)phenol exposure in larger populations is needed.

Juniperus sabina L. as a Source of Podophyllotoxins: Extraction Optimization and Anticholinesterase Activities

Juniperus sabina L. (J. sabina) has been an important plant in traditional medicine since ancient times. Its needles are rich in podophyllotoxin, a precursor compound to anti-tumor drugs. However, no systematic research has been done on J. sabina as a source of podophyllotoxins or their biological action. Hence, extracts of podophyllotoxin and deoxypodophyllotoxin were the main optimization targets using the Box–Behnken design (BBD) and response surface methodology (RSM). The total phenol content and antioxidant activity of J. sabina needle extract were also optimized. Under the optimal process conditions (ratio of material to liquid (RLM) 1:40, 90% methanol, and ultrasonic time 7 min), the podophyllotoxin extraction rate was 7.51 mg/g DW, the highest level reported for Juniperus spp. distributed in China. To evaluate its biological potential, the neuroprotective acetyl- and butyrylcholinease (AChE and BChE) inhibitory abilities were tested. The needle extract exhibited significant anti-butyrylcholinesterase activity (520.15 mg GALE/g extract), which correlated well with the high levels of podophyllotoxin and deoxypodophyllotoxin. This study shows the potential medicinal value of J. sabina needles.

Sex-Related Differences on Chemical Composition, Anatomy, Histochemistry, and Biological Activities of Juniperus rigida

Sex-related differences on phenolic profiles, chemical composition of essential oils, anatomy, histochemistry and biological activities (antioxidant and antibacterial activities) of Juniperus rigida needles collected from Yijun and Fugu region were first studied. In two regions, female and male had similar contents of total phenolic and total flavonoid. 10 phenolic compounds were analyzed by RP-HPLC, amentoflavone content was significantly higher in female than male in Yijun, and chlorogenic acid content was significantly higher in female than male in Fugu. 30 compounds (over 0.5 %) were detected in the essential oils, and the total contents of female were lower than male in Yijun. This difference mainly comes from Germacrene D, which was about twice as high in male as in female. Male needles had significantly larger mechanical tissue and phloem in Yijun. Histochemical analysis indicated that the phenols were stored in epidermal cells, sponge tissue, endodermis cells, edge of resin duct, stomatal bands, and the flavonoids were stored in epidermal cells, endodermis cells, edge of resin duct, stomatal bands. No sex-related differences were found in histochemical analysis, antioxidant activities (ABTS, FRAP) and antibacterial activities (9 strains). This preliminary study provided a reference for production practice and theoretical research of J. rigida.

Comprehensive Analysis of the Herbal Mixture Made of Juniperus oxycedrus L. Berries, Inner Bark of Betula pendula Roth., and Grains of Avena sativa L

This is the first report of the high-performance liquid chromatography and gas chromatography–mass spectrometry profile of a herbal mixture (HM) made of Juniperus oxycedrus L. (redberry juniper) berries, inner bark of Betula pendula Roth. (silver birch), and grains of Avena sativa L. (oat), and its effect on the No. of micronuclei (MN) in human lymphocytes and toxicity toward Artemia salina. Constituents represented by over 1000 µg per g of methanol dry extract were gallic acid, protocatechuic acid, and amentoflavone. The methanol extract of the HM at a concentration of 2.0 μg/mL decreased MN frequency by 38.3%, which was more than 3 times greater than that of the radioprotectant amifostine. The essential oil isolated from the HM was composed mainly of β-myrcene (32%) and showed weaker toxicity toward Artemia salina than the positive control after both incubation periods (24 h and 48 h). These findings suggest that the examined HM, beside its ethnopharmacological relevance on the elimination of renal calculi, also significantly reduces the No. of MN in human lymphocytes.

Selenium, Sulfur, and Methyl Jasmonate Treatments Improve the Accumulation of Lutein and Glucosinolates in Kale Sprouts

Kale sprouts contain health-promoting compounds that could be increased by applying plant nutrients or exogenous phytohormones during pre-harvest. The effects of selenium (Se), sulfur (S), and methyl jasmonate (MeJA) on lutein, glucosinolate, and phenolic accumulation were assessed in kale sprouts. Red Russian and Dwarf Green kale were chamber-grown using different treatment concentrations of Se (10, 20, 40 mg/L), S (30, 60, 120 mg/L), and MeJA (25, 50, 100 µM). Sprouts were harvested every 24 h for 7 days to identify and quantify phytochemicals. The highest lutein accumulation occurred 7 days after S 120 mg/L (178%) and Se 40 mg/L (199%) treatments in Red Russian and Dwarf Green kale sprouts, respectively. MeJA treatment decreased the level of most phenolic levels, except for kaempferol and quercetin, where increases were higher than 70% for both varieties when treated with MeJA 25 µM. The most effective treatment for glucosinolate accumulation was S 120 mg/L in the Red Russian kale variety at 7 days of germination, increasing glucoraphanin (262.4%), glucoerucin (510.8%), 4-methoxy-glucobrassicin (430.7%), and glucoiberin (1150%). Results show that kales treated with Se, S, and MeJA could be used as a functional food for fresh consumption or as raw materials for different industrial applications.

Enhancing the Extraction of Phenolic Compounds from Juniper Berries Using the Box-Behnken Design

Juniper berry is an important medicinal plant used in pharmaceutical and petrochemical industries thanks to its strong antioxidant potential, which is attributed to the presence of phenolic compounds. In this study, four different solvents, namely, aqueous acetone, aqueous ethanol, aqueous NaOH, and water, were used in the extraction process with a view to optimize and determine the polyphenolic contents in the juniper berry using ultraviolet (UV) spectrophotometry. Many experiments were performed at different solvent concentrations, time, temperature, and liquid-solid ratio. The models to evaluate the effects and the optimum of these variables on the polyphenols extraction using the response surface methodology (RSM) were developed. The predicted values of the polyphenol content of juniper berry were thus highly correlated with costly measured values (SECV = 0.14 and R ² = 0.97), and the optimal conditions of extraction were determined for the different solvents. Following the numerical optimization, the maximum predicted polyphenol contents obtained under the optimum extraction conditions are as follows: 17.57% for 58 °C extraction temperature, 78.5 min extraction time, 60% acetone concentration, and 29.8 liquid-solid ratio for the aqueous ethanol extraction; 20.68% for 71.46 °C extraction temperature, 79.2 min extraction time, 21.9% ethanol concentration, and 26.4:1 liquid-solid ratio for the aqueous acetone extraction; 34.51% for 96.4 °C extraction temperature, 37.7 min extraction time, 1.48% NaOH concentration, and 15.2:1 liquid-solid ratio for the aqueous NaOH extraction; and 9.8% was obtained under the optimum extraction conditions of 69 °C extraction temperature, 126 min extraction time, and 23:1 liquid-solid ratio for the water extraction. The GC-MS analysis of the chemical composition of juniper Berry revealed 60 identified components that represent 97.43% of the sample. The predominant fraction was monoterpene representing 80.87% especially for α-pinene (39.12%), β-pinene (12. 68%), and myrcene (12.92%). In the other fraction of sesquiterpene representing 16.54%, the predominant components were β-caryophyllene (4.41%) and germacrene D (4.23%).

LC-ESI-QTOF/MS Characterization of Phenolic Compounds from Medicinal Plants (Hops and Juniper Berries) and Their Antioxidant Activity

Hops (Humulus lupulus L.) and juniper berries (Juniperus communis L.) are two important medicinal plants widely used in the food, beverage, and pharmaceutical industries due to their strong antioxidant capacity, which is attributed to the presence of polyphenols. The present study is conducted to comprehensively characterize polyphenols from hops and juniper berries using liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS) to assess their antioxidant capacity. For polyphenol estimation, total phenolic content, flavonoids and tannins were measured, while for antioxidant capacity, three different antioxidant assays including the 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay, the 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical cation decolorization assay and the ferric reducing-antioxidant power (FRAP) assay were used. Hops presented the higher phenolic content (23.11 ± 0.03 mg/g dw) which corresponded to its strong antioxidant activity as compared to the juniper berries. Using LC-ESI-QTOF/MS, a total of 148 phenolic compounds were tentatively identified in juniper and hops, among which phenolic acids (including hydroxybenzoic acids, hydroxycinnamic acids and hydroxyphenylpropanoic acids) and flavonoids (mainly anthocyanins, flavones, flavonols, and isoflavonoids) were the main polyphenols, which may contribute to their antioxidant capacity. Furthermore, the HPLC quantitative analysis showed that both samples had a high concentration of phenolic acids and flavonoids. In the HPLC quantification, the predominant phenolic acids in hops and juniper berries were chlorogenic acid (16.48 ± 0.03 mg/g dw) and protocatechuic acid (11.46 ± 0.03 mg/g dw), respectively. The obtained results highlight the importance of hops and juniper berries as a rich source of functional ingredients in different food, beverage, and pharmaceutical industries.

Juniperus chinensis Fruits Attenuate Oxazolone- and 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis Symptoms in Mice

Juniperus chinensis, commonly Chinese juniper, has been used for treating inflammatory diseases. This study aimed to investigate anti-atopic dermatitis (AD) effects of standardized J. chinensis fruits extract on murine oxazolone- and 2,4-dinitrochlorobenzene (DNCB)-induced models of AD. Ear swelling, epidermis thickening, and eosinophils infiltration in the oxazolone-mediated dermatitis of BALB/c mice were significantly reduced upon topical application of J. chinensis fruits 95% EtOH extract (JCE). Besides, transdermal administration of JCE to SKH-1 hairless mice inhibited the development of DNCB-induced AD-like skin lesions by suppressing transepidermal water loss and improving skin hydration. Decreased total serum immunoglobulin E (IgE) and interleukin (IL)-4 levels could be observed in atopic dorsal skin samples of JCE-treated group. According to the phytochemical analysis, JCE was found to contain isoscutellarein-7-O-β-D-xyloside, cupressuflavone, and amentoflavone as main compounds. Therapeutic attempts with the J. chinensis fruits might be useful in the treatment of AD and related skin inflammatory diseases.

Isolation of tyrosinase and melanogenesis inhibitory flavonoids from Juniperus chinensis fruits

A new biflavonoid, amentoflavone-7-O-β-D-glucoside, and thirteen known flavonoids were isolated from the fruits of Juniperus chinensis using a bioactivity-guided method and their tyrosinase inhibitory effects were tested using a mushroom tyrosinase bioassay. Two isolates, hypolaetin-7-O-β-D-glucoside and quercetin-7-O-α-L-rhamnoside, were found to reduce tyrosinase activity at a concentration of 50 μM. Quercetin-7-O-α-L-rhamnoside attenuated cellular tyrosinase activity and melanogenesis in α-MSH plus IBMX-stimulated B16F10 melanoma cells. Molecular docking simulation revealed that quercetin-7-O-α-L-rhamnoside inhibits tyrosinase activity by hydrogen bonding with residues His85, His244, Thr261, and Gly281 of tyrosinase. Abbreviations: EtOH, ethanol; CH2Cl2, dichloromethane; EtOAc, ethylacetate; n-BuOH, n-butanol; MeOH, metanol; CHCl3,chloroform; DMSO, dimethylsulfoxide; DMEM, Dulbecco's modified Eagle's medium; FBS, fetal bovine serum; α-MSH, α-melanocyte stimulating hormone; L-DOPA, L-3, 4-dihydroxyphenylalanine.

Antibacterial and antioxidant activity of Juniperus thurifera L. leaf extracts growing in East of Algeria

Aim

This work aimed to evaluate the biological activity of the leaf extracts of Juniperus thurifera L., which is an Algerian endemic tree that belongs to the family of Cupressaceae.

Materials and Methods

The plant leaves were extracted in solvents of increasing polarity to obtain different extracts such as methanol, petroleum ether, chloroform, ethyl acetate, and aqueous extracts (MeE, PEE, ChlE, EtAE, and AqE). The antioxidant activity of four extracts (MeE, ChlE, EtAE, and AqE) was assessed by trapping test of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The evaluation of antibacterial activity of MeE, ChlE, EtAE, and PEE was done using the disk diffusion method on solid agar.

Results

The three extracts of EtAE, AqE, and MeE showed high antiradical activity toward the DPPH radical (IC₅₀=29.348 µg/mL, 37.538 µg/mL, and 52.573 µg/mL, respectively), while the lowest radical scavenging activity was expressed by the ChlE (IC₅₀=70.096 µg/mL). These extracts were active only toward the Gram-positive bacteria (Staphylococcus aureus ATCC and methicillin-resistant S. aureus) at different concentrations, and the highest activity was obtained with the ChlE with an inhibition diameter of 14 mm at the concentration of 1 g/mL. No inhibition was detected for all of these extracts against the Gram-negative tested strains (Escherichia coli ATCC, Pseudomonas aeruginosa ATCC, and Enterobacter cloacae (extended spectrum β-lactamase).

Conclusion

From this study, on the one hand, it was concluded that J. thurifera L. leaves extracts exhibited a very intense antioxidant potential toward the DPPH radical, and on the other hand, the antibacterial activity showed an action spectrum exclusively toward the Gram-positive bacteria.

Contribution of the Glucosinolate Fraction to the Overall Antioxidant Potential, Cytoprotection against Oxidative Insult and Antimicrobial Activity of Eruca sativa Mill. Leaves Extract

Background

Eruca sativa Mill. (Brassicaceae) is commonly utilized as an ingredient in salads and also as a folk remedy to treat various diseases.

Objective

The objective of this study was to establish the contribution of the glucosinolate (GLS) fraction to the overall antioxidant, cytoprotection against oxidative insult and antimicrobial properties of the hydro-alcoholic extract of E. sativa leaves from Sicily (Italy), characterized phytochemically.

Materials and Methods

The antioxidant activity was evaluated by different in vitro systems. The cytoprotective effect against hydrogen peroxide (H₂O₂)-induced oxidative stress was tested in human peripheral blood mononuclear cells (PBMCs). The antimicrobial potential against bacteria and fungi was assayed by standard methods.

Results

E. sativa extract exhibited both radical scavenging (50% inhibitory concentration [IC₅₀] 1.04 ± 0.04 mg/mL) and ferrous ions-chelating activity (IC₅₀ 0.327 ± 0.0032 mg/mL) and mild reducing power; the GLS fraction showed chelating ability only (IC₅₀ 0.225 ± 0.009 mg/mL). In the experimental model of H₂O₂-induced oxidative stress in human PBMCs, a significant cytoprotective effect and a suppression of reactive oxygen species production by both extract and GLS fraction were observed (P < 0.001). E. sativa extract displayed moderate antimicrobial activity against Gram-positive bacteria, and Staphylococcus aureus was the most sensitive strain (minimum inhibitory concentration 0.125 mg/mL), whereas the GLS fraction was not active.

Conclusion

GLSs are not involved in the primary antioxidant activity of E. sativa leaf extract but they are, almost in part, responsible for its ferrous ion-chelating properties. Iron-chelating compounds in E. sativa extract may protect cells under conditions of oxidative stress, and GLSs might play a chief role in this effect.

SUMMARY

Eruca sativa Mill. leaf extract exhibited antioxidant activity in different in vitro systems, whereas the glucosinolate (GLS) fraction showed Fe²⁺-chelating ability onlyA significant cytoprotective effect and a suppression of intracellular reactive oxygen species production by both extract and GLS fraction were observed in human peripheral blood mononuclear cellsE. sativa extract displayed moderate antimicrobial activity against Gram-positive bacteria, whereas the GLS fraction was not active. Abbreviations used: GLS: Glucosinolate; H₂O₂: Hydrogen peroxide; PBMCs: Peripheral blood mononuclear cells; IC₅₀: 50% inhibitory concentration; MIC: Minimum inhibitory concentration.

Allelopathic Effects, Physiological Responses and Phenolic Compounds in Litter Extracts of Juniperus rigidaSieb. et Zucc

The allelopathic effects of Juniperus rigida litter aqueous extract (LE) on wheat and Pinus tabuliformis were studied, as well as the physiological responses to the extract. High concentration LE (0.10 g Dw/ml) significantly inhibited the seed germination and seedling growth in receptor plants. The chlorophyll content and root activity in the wheat seedlings were reduced significantly across all treatments; however, those were more prominently reduced at high concentration (0.10 g Dw/ml) but received little stimulation at low concentration (0.025 g Dw/ml) in P. tabuliformis. The content of malonaldehyde (MDA) increased with increasing concentrations of LE, except at 0.025 g Dw/ml. Activities of antioxidant enzymes (POD, CAT and SOD) in receptor plants were all significantly inhibited at high concentrations but stimulated at low concentrations. These results demonstrate that the aqueous extract from J. rigida litter has allelopathic potential. Various phenolic compounds were identified in litter aqueous extract and litter ethanol extract by HPLC. The phenolic compound content in the aqueous extract was significantly lower than that in the ethanol extract. Chlorogenic acid and podophyllotoxin were the predominant phenolic compounds in both types of litter extracts. These findings suggest that the seed germination and seedling growth of P. tabuliformis and wheat would be inhibited when planted near large amounts J. rigida litter.

The Impact of Ozone Treatment in Dynamic Bed Parameters on Changes in Biologically Active Substances of Juniper Berries

The development of the parameters of ozone decontamination method assuring the least possible losses of biologically active substances (essential oils and polyphenols) and their activity in common juniper (Juniperus communis (L.)) berries was studied. Ozone treatment in dynamic bed was conducted 9 times. The process was conducted under different ozone concentrations (100.0; 130.0; 160.0 g O₃/m³) and times (30, 60, 90 min). After each decontamination, the microbiological profile of the juniper berries was studied, and the contaminating microflora was identified. Next to the microbiological profile, the phenolic profile, as well as antioxidant activity of extracts and essential oils were determined. The total polyphenol content (TPC), composition of essential oils, free radical-scavenging capacity, total antioxidant capacity, ferric-reducing antioxidant power (FRAP), beta-carotene bleaching test (BCB) and LC-MS polyphenol analysis were carried out. The study reveals that during short ozone contact times, higher amounts of TPC, 15.47 and 12.91 mg CE/g of extract, for samples 100/30 and 130/30, respectively, were demonstrated. Whereas samples 100/60, 130/60, 100/90, and 160/90 exhibited the lowest amount of phenolics. The highest antioxidant activity was found in the methanol extract obtained from ozonated berries which exhibited the lowest IC₅₀ in all the antioxidant assays, such as DPPH, FRAP, and BCB assays. Ozone treatment showed noteworthy potential and its usage in food manufacturing and as an alternative decontamination method should be considered.

Role of the flavonoid-rich fraction in the antioxidant and cytotoxic activities of Bauhinia forficata Link. (Fabaceae) leaves extract

Bauhinia forficata Link. is utilised as an antidiabetic in Brazilian folk-medicine; furthermore, its antioxidant properties suggest a potential usefulness in the prevention of diabetes complications associated with oxidative stress. The contribution of a flavonoid-rich fraction (FRF), HPLC-PDA-ESI-MS characterised, to the antioxidant and cytotoxic properties of B. forficata hydro-alcoholic leaves extract was evaluated for the first time. Both extract and FRF showed radical-scavenging activity and reducing power with a strong relationship with the flavonoid content found; hence, flavonoids are mainly responsible for the primary antioxidant activity of B. forficata extract. The extract significantly decreased FO-1 cell viability at the higher concentrations. FRF did not exert any effect; thus, flavonoids do not appear to be responsible for the cytotoxicity of the extract. The extract resulted virtually non-toxic against both Artemia salina and normal human lymphocytes, demonstrating potential selectivity in inhibiting cancer cell growth. Finally, no antimicrobial activity was observed against the bacteria and yeasts tested.

Brine shrimp cytotoxic activity of methanolic extracts of Juniperus communis L. berries

Methanolic extracts from Juniperus communis L. berries collected from five different localities in the Republic of Macedonia were evaluated for their cytotoxicity by Brine shrimp lethality assay. The obtained cytotoxic activity is descending as follows: Pelister (128 μg/ mL) > Jakupica (221 μg/mL) > Prilep (662 μg/mL) > Demir Hisar (863 μg/mL) > Makedonski Brod (969 μg/mL). Berries collected from mountain areas (Pelister and Jakupica) demonstrated prominent cytotoxic effects, while berries collected from localities near urban areas exhibited lower cytotoxicity. Variations in their bioactivity are probably due to their complex phytochemical composition, which may vary with different ecological and geographical conditions.

Two New Compounds from Gorgonian-associated Fungus Aspergillus sp

One new γ-lactone derivative 5-hydroxy-3-isopropyl-4-methoxyfuranone (1) and one new lactam derivative dehydrated-marinamide (2), along with two known compounds marinamide (3) and marinamide methyl ester (4) were isolated from the fermentation broth of the marine gorgonian-associated fungus Aspergillus sp. SCSGAF0093. Their structures were elucidated on the basis of spectroscopic and spectrometric analysis. Compound 1 showed significant toxicity to brine shrimp (Artemia salina) with a median lethal concentration (LC50) of 1.25 μM, and 3 inhibited protein tyrosine phosphatase 1B (PTPlB) with a half maximal inhibitory concentration (IC50) of 23.3 μg/mL.

Antibacterial activities of almond skins on cagA-positive and-negative clinical isolates of Helicobacter pylori

BACKGROUND

Helicobacter pylori is known to be a gastric pathogen of humans. Eradication regimens for H. pylori infection have some side effects, compliance problems, relapses, and antibiotic resistance. Therefore, the need for alternative therapies for H. pylori infections is of special interest. We have previously shown that polyphenols from almond skins are active against a range of food-borne pathogens. The aim of this study was to evaluate the antibacterial effects of natural almond skins before and after simulated human digestion and the pure flavonoid compounds epicatechin, naringenin and protocatechuic acid against H. pylori.

RESULTS

H. pylori strains were isolated from gastric biopsy samples following standard microbiology procedures. Also, cagA and vacA genes were identified using PCR. Susceptibility studies on 34 strains of H. pylori, including two reference strains (ATCC 43504, ATCC 49503), were performed by the standard agar dilution method.

CONCLUSIONS

Polyphenols from almond skins were effective in vitro against H. pylori, irrespective of genotype status and could therefore be used in combination with antibiotics as a novel strategy for antibiotic resistance.

In vitro antimicrobial activity of pistachio (Pistacia vera L.) polyphenols

We investigated the antimicrobial properties of polyphenol-rich fractions derived from raw shelled and roasted salted pistachios. American Type Culture Collection (ATCC), food and clinical isolates, of Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Pseudomonas mirabilis), Gram-positive bacteria (Listeria monocytogenes, Enterococcus hirae, Enterococcus faecium, Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus aureus), the yeasts Candida albicans and Candida parapsilosis and the fungus Aspergillus niger were used. Pistachio extracts were active against Gram-positive bacteria with a bactericidal effect observed against L. monocytogenes (ATCC strains and food isolates), S. aureus and MRSA clinical isolates. Extracts from raw shelled pistachios were more active than those from roasted salted pistachios. The bactericidal activity of pistachio extracts could be used to help control the growth of some microorganisms in foods to improve safety and may find application as a topical treatment for S. aureus.