GC/MS analysis and antimicrobial and antioxidant activities of essential oil of Eucalyptus radiata

BACKGROUND: The essential oil from Eucalyptus radiata leaves collected in Tunisia was extracted by steam distillation and analysed by gas chromatography/flame ionisation detection and gas chromatography/mass spectrometry. Its antioxidant and antiradical properties were evaluated by the 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2′‐azinobis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS) assays. The antimicrobial activity of the oil was examined in vitro against two plant‐pathogenic bacteria (four strains each of Agrobacterium tumefaciens and Pseudomonas savastanoi pv. savastanoi) and two plant‐pathogenic fungi (Fusarium solani and Rhizoctonia solani). RESULTS: Thirty‐five compounds were identified and quantified in the essential oil, the major ones being 1,8‐cineole (69.53%), α‐pinene (11.94%) and trans‐pinocarveol (4.81%). Medium antioxidant activity was found in the ABTS assay (IC₅₀ = 484.3 ± 17.3 mg L^?1), whereas no significant free radical‐scavenging activity was detected in the DPPH assay (IC₅₀ > 10 000 mg L^?1). The antimicrobial assays showed that the oil exhibited a high level of activity against A. tumefaciens and R. solani, with minimum inhibitory concentrations ranging between 750 and 1000 µL L^?1. However, it was less efficient against P. savastanoi pv. savastanoi and F. solani. CONCLUSION: The results indicate that the essential oil of E. radiata, with a high content of terpenic compounds, exhibits significant antimicrobial activity against strains of A. tumefaciens and the fungus R. solani and may therefore be useful for their control. Copyright © 2009 Society of Chemical Industry     

Chemical composition and antimicrobial activity of the essential oil of Amomum tsao‐ko

BACKGROUND: The chemical composition of the essential oil obtained by hydrodistillation from the dried fruits of Amomum tsao‐ko was analysed by gas chromatography/mass spectroscopy (GC/MS). The antimicrobial activity of the oil was evaluated against 16 micro‐organisms using agar disc diffusion and broth microdilution methods. RESULTS: Seventy‐three compounds, constituting about 97.56% of the total oil, were identified. The main components were 1,8‐cineole (45.24%), ρ‐propylbenzaldehyde (6.04%), geraniol (5.11%), geranial (4.52%), α‐terpineol (3.59%) and α‐phellandrene (3.07%). The essential oil showed a broad spectrum of antimicrobial activity against all the tested micro‐organisms, including Gram‐positive and Gram‐negative bacteria, and fungi. The oil exerted the strongest bactericidal activity against Staphylococcus aureus CCTCC AB91118, with minimum inhibitory and bactericidal concentrations of 0.20 g L^?1. CONCLUSION: Our study suggests that the Amomum tsao‐ko essential oil could be one of new medicinal resources for antibacterial and antifungal agents. Copyright © 2008 Society of Chemical Industry     

Biological activities of the essential oil and methanolic extract of Micromeria fruticosa (L) Druce ssp serpyllifolia (Bieb) PH Davis plants from the eastern Anatolia region of Turkey

The in vitro antimicrobial and antioxidant activities of the essential oil and methanolic extract of Micromeria fruticosa ssp serpyllifolia as well as the composition of the essential oil were examined. The essential oil exhibited activity against 14 bacteria, three fungi and a yeast, with minimal inhibitory concentration (MIC) values ranging from 31.25 to 125 µl ml^?1, whilst the methanolic extract was inactive. Antioxidant activity was measured by two methods, namely scavenging of the free radical DPPH and inhibition of linoleic acid oxidation. The methanolic extract exhibited significant antioxidant activity in both assays, providing 50% inhibition at 70.9 ± 0.5 µg ml^?1 concentration in the DPPH assay and inhibiting linoleic acid oxidation to 59% at 2 mg ml^?1 concentration, whilst the essential oil showed activity only at higher concentrations. The gallic acid equivalent total phenolic content of the methanolic extract was found to be 55.2 ± 2.00 µg mg^?1 dry weight extract (5.5% w/w). The chemical composition of the hydrodistilled essential oil was analysed by means of GC/MS. Twenty‐nine constituents were identified, the main ones being piperitenone (50.61%) and pulegone (29.19%). Copyright © 2004 Society of Chemical Industry     

Volatile compounds and antimicrobial and antioxidant activities of the essential oils of the needles of Pinus densiflora and Pinus thunbergii

BACKGROUND: To investigate the volatile compounds and the antibacterial and antioxidant effects of the essential oils of Pinus densiflora needles (EPDN) and Pinus thunbergii needles (EPTN), the volatile compounds of steam‐distilled essential oils were analysed by gas chromatography–mass spectrometry. Antibacterial activities were analysed by performing disc‐agar diffusion assay and determining the minimum inhibitory concentrations (MICs) of the essential oils. Antioxidant activities were analysed via radical‐ and nitrite‐scavenging activity assays. RESULTS: The yields of EPDN and EPTN were 0.304% (v/w) and 0.296% (v/w), respectively. In the antibacterial activity assay, the MICs of EPDN and EPTN for Klebsiella pneumoniae, Shigella flexneri and Proteus vulgaris were < 0.4 mg mL^?1. In the antioxidant activity assay, the 50% inhibitory concentrations (IC₅₀) of EPDN and EPTN were 120 and 30 µg mL^?1, respectively. At 1680 µg mL^?1, both EPDN and EPTN exhibited > 50% nitrite‐scavenging activity. CONCLUSION: EPDN can be used as a natural antimicrobial substance. Copyright © 2011 Society of Chemical Industry     

Chemical composition,antioxidant and cytotoxicity activities of the essential oils of Myristica fragrans and Morinda citrifolia

BACKGROUND: In this study the chemical composition, antioxidant activities and cytotoxic effect of the essential oils of Myristica fragrans (nutmeg) and Morinda citrifolia (mengkudu) were determined. RESULTS: Thirty‐eight compounds in nutmeg oil and six compounds in mengkudu oil were identified by gas chromatography–mass spectrometry. The free radical scavenging activity of nutmeg oil was superior of that mengkudu oil. The MTT assay of nutmeg oil on human colorectal carcinoma (HCT‐116) and human breast carcinoma (MCF‐7) cell lines showed IC₅₀ values of 78.61 and 66.45 µg mL^?1, respectively. The mengkudu oil exhibited IC₅₀ values of 91.46 and 78.15 µg mL^?1 for HCT‐116 and MCF‐7, respectively. CONCLUSION: The results showed that nutmeg oil can be developed as potent anti‐cancer and antioxidant drugs. Copyright © 2011 Society of Chemical Industry     

The influence of organ,season and drying method on chemical composition and antioxidant and antimicrobial activities of Juniperus phoenicea L. essential oils

BACKGROUND: Juniperus phoenicea is an important medicinal plant. In the present study, essential oils (18 samples) from leaves and berries of Juniperus phoenicea L. (Cupressaceae), obtained by various drying methods and in different collection months, were analysed by gas chromatography–mass spectrometry and also evaluated for in vitro antimicrobial and antioxidant activities. Correlations were studied between antimicrobial activity and the chemical composition of essential oils. RESULTS: Sixty‐seven compounds were identified in essential oils, representing 97.7–100%. Essential oils were dominated by monoterpenes and sesquiterpenes, which presented 35.0–93.3% and 6.7–62.0%, respectively, depending of organ, season and drying method. Antimicrobial tests showed that essential oils strongly inhibited the growth of Gram‐positive microorganisms and Mucor ramamnianus, but was inactive against Gram‐negative strains. Antioxidant activity was tested using the ABTS radical‐scavenging assay. Most samples showed good activity (the best IC₅₀ = 41.7 ± 1.5 mg L^?1). CONCLUSIONS: It could be concluded that drying of leaves of J. phoenicea in the sun and berries in oven‐drying was more suitable and was recommended for obtaining higher essential oil yield, but for a higher percentage of some special components such as α‐pinene and δ‐3‐carene shade‐drying was more suitable. Copyright © 2009 Society of Chemical Industry     

Chemical composition,antioxidant activity and anti‐lipase activity of Origanum vulgare and Lippia turbinata essential oils

This study reported the chemical composition, phenolic content, antioxidant and anti‐lipase activity of oregano and Lippia essential oils. The major compounds found in oregano essential oil were γ‐terpinene (32.10%), α‐terpinene (15.10%), p‐cymene (8.00%) and thymol (8.00%). In Lippia essential oil, α‐limonene (76.80%) and 1,8‐cineole (4.95%) represented the major compounds. Oregano essential oil had higher phenolic content (12.47 mg gallic acid mL^?1) and DPPH scavenging activity (IC₅₀ 0.357 μg mL^?1) than Lippia essential oil (7.94 mg gallic acid mL^?1 and IC₅₀ 0.400 μg mL^?1, respectively). Both essential oils had similar antioxidant indexes (about 1.2) determined by Rancimat. Moreover, oregano essential oil had also higher anti‐lipase activity (IC₅₀ 5.09 and 7.26 μg mL^?1). Higher phenolic content in the essential oils was related with higher scavenging and anti‐lipase activities. Oregano and Lippia essential oils could be used as natural antioxidants on food products.     

Bioactivities of essential oil and extract of Thymus argaeus,Turkish endemic wild thyme

BACKGROUND: Thymus argaeus Boiss. & Bal. (Lamiaceae), an endemic plant species of Turkey known as wild thyme, is traditionally used as a spice and a wild tea in the Inner Anatolia region of Turkey. In this study the composition of the essential oil and the antimicrobial and antioxidant effects of the methanolic extract and essential oil of T. argaeus were determined. RESULTS: The main components of the essential oil were linalool (499 g kg^?1), α‐terpineol (150 g kg^?1), linalyl acetate (97 g kg^?1) and thymol (94 g kg^?1). The total phenolic, flavanol and flavonol contents of the extract were 83.31 ± 0.59 mg gallic acid equivalent g^?1, 6.26 ± 0.00 mg catechin equivalent g^?1 and 28.81 ± 0.21 mg rutin equivalent g^?1 respectively. The antioxidant activities of the extract and essential oil determined by the 2,2‐diphenyl‐1‐picrylhydrazyl radical‐scavenging method were 830.18 ± 0.42 and 20.47 ± 2.3 mg g^?1 respectively. The antimicrobial activities of the extract and essential oil against 13 bacteria and two yeasts were studied by the agar diffusion method. The micro‐organisms most sensitive to the essential oil were Aeromonas hydrophila and Pseudomonas aeruginosa, while the micro‐organism most sensitive to the extract was P. aeruginosa. CONCLUSION: Only the extract of T. argaeus could be used as a natural antioxidant, while both the extract and the essential oil could be useful as natural antimicrobial agents in food preservation. Copyright © 2009 Society of Chemical Industry     

Chemical composition and in vitro control of agricultural plant pathogens by the essential oil and various extracts of Nandina domestica Thunb.

BACKGROUND: The aims of this study were to examine the chemical composition of the essential oil isolated from the floral parts of Nandina domestica Thunb. by hydrodistillation, and to test the efficacy of essential oil and various leaf extracts (n‐hexane, chloroform, ethyl acetate and methanol) as an antifungal potential against a panel of agricultural plant pathogens. RESULTS: The GC‐MS analysis determined that 79 compounds, which represented 87.06% of total oil, were present in the oil containing mainly 1‐indolizino carbazole (19.65%), 2‐pentanone (16.4%), mono phenol (12.1%), aziridine (9.01%), methylcarbinol (4.6%), ethanone (3.3%), furfural (2.96%), 3,5‐dimethylpyrazole (1.29%) and 2(5H)‐furanone (1.32%). The oil (1000 ppm disc^?1) and the leaf extracts (1500 ppm disc^?1) revealed remarkable antifungal effect against Fusarium oxysporum, Fusarium solani, Phytophthora capsici, Colletotrichum capsici, Sclerotinia sclerotiorum, Botrytis cinerea and Rhizoctonia solani in the growth inhibition range of 53.3–64.3% and 33.3–56.0%, respectively, along with their respective values for mimimum inhibitory concentration (MIC) ranging from 125 to 1000 µg mL^?1 and 500 to 2000 µg mL^?1. The values for minimal fungicidal concentration (MFC) of the oil and extracts were obtained in the range of 125 to 1000 µg mL^?1 and 500 to 2000 µg mL^?1, respectively. The essential oil also had a strong detrimental effect on spore germination of all the plant pathogens tested along with concentration as well as time‐dependent kinetic inhibition of B. cinerea. CONCLUSION: The results obtained in this study demonstrate that N. domestica mediated oil and extracts could become potential alternatives to synthetic fungicides for controlling certain important agricultural plant pathogenic fungi. Copyright © 2008 Society of Chemical Industry     

Chemical Composition,Antimicrobial, and Antioxidant Activities of Essential Oil and Ethanol Extract of Coriandrum sativum L. Leaves from Turkey

This study reports the chemical composition, antioxidant, and antimicrobial activity of the essential oil and ethanol extract of Coriandrum sativum L. leaves. Gas chromatography/mass spectrometry analysis identified 19 compounds representing 95.30% of the oil. (E)-2-decenal (29.87%), linalool (21.61%), (E)-2-dodecenal (7.03%), dodecanal (5.78%), (E)-2-undecenal (3.84%), (E)-2-tridecenal (3.56%), (E)-2-hexadecenal (2.47%), tetradecenal (2.35%), and α-pinene (1.64%) were the main components identified in the essential oil. The samples were screened for their antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl radical scavenging and β-caroten bleaching assay. IC₅₀ value for ethanol extract of C. sativum was determined as 74.87 ± 0.03 μg/mL. Total antioxidant activity value for C. sativum ethanol extract was 85.85 ± 0.04%. Total phenolic content for ethanol extract of the plant was determined as 14.97 ± 0.05 mg gallic acid equivalents/g dry weight. The essential oil and ethanol extract were also tested for antimicrobial activity against 28 different foodborne microorganisms, including 19 bacteria, 7 fungi, and 2 yeast species. The ethanol extract of the plant showed weak antimicrobial activities against microbial strains in both disc diffusion and minimal inhibition concentration tests. This study suggested that Coriandrum sativum L. leaves may be used as a potential source of food flavoring, and for their antioxidants and antimicrobial properties.     

Chemical composition,antibacterial and antifungal activities of seed essential oil of Ferulago angulata

The aim of this study was to determine the chemical composition and the in vitro antimicrobial effects of seed essential oil of Ferulago angulata. The oil analyses by GC and GC/MS resulted in the identification of 39 compounds representing 91.07% of the oil. The major constituents were (Z)-β-ocimene (19.93%), α-pinene (15.50%), p-cymene (7.67%), sabinene (7.49%), β-phellandrene (5.5%), and α-phellandrene (4.95%). The oil was also screened for its antimicrobial properties against six bacteria (Erwinia amylovora, Xanthomonas oryzae, Pseudomonas syringae, Pectobacterium carotovorum, Ralstonia solanacearum, Bacillus thuringiensis) and six fungi (Alternaria alternata, Culvularia fallax, Macrophomina phaseolina, Fusarium oxysporum, Cytospora sacchari, Colletotrichum tricbellum). According to the results of antibacterial activity, B. thuringiensis (with 8 µL mL^?1 minimal inhibitory concentration (MIC) and 15 µL mL^?1 minimum bactericidal concentration (MBC)) was the most sensitive bacterium; P. carotovorum and R. solanacearum (with 20 µL mL^?1 MIC and 30< MBC) were the most resistant bacteria. Additionally, a broad differentiation against all of the tested fungi showed that the most susceptible and resistant fungi after 6 days at the highest concentration (800 µL L^?1) were F. oxysporum (100.0 ± 0.00%) and C. tricbellum (52.50 ± 1.67%) of growth inhibition, respectively.     

Phytochemicals content,antioxidant and hypoglycaemic activities of commercial nutmeg mace (Myristica fragrans L.) and pimento (Pimenta dioica (L.) Merr.)

Commercially dried powder of nutmeg mace (Myristica fragrans) and pimento (Pimenta dioica) spices was investigated for their high performance liquid chromatography phenolic profile and their antioxidant and hypoglycaemic properties by α‐amylase and α‐glucosidase inhibition tests. Generally, mace showed the most promising activity. An interesting protection of lipid peroxidation with an IC₅₀ value of 7.7 μg mL^?1 was found. A significant result was also obtained in ferric reducing ability power assay if compared to the positive control butylated hydroxytoluene (IC₅₀ value of 68.7 μg mL^?1 vs. 63.2 μg mL^?1, respectively). Mace also exhibited the highest carbohydrate‐hydrolysing enzyme inhibitory activity with IC₅₀ values of 62.1 and 75.7 μg mL^?1 against α‐amylase and α‐glucosidase, respectively. Overall, these results support the use of these spices not only as flavouring agent but also as food preservative and functional ingredients.     

Antioxidant and antimicrobial activities of essential oil and various oleoresins of Elettaria cardamomum (seeds and pods)

BACKGROUND: This paper describes the chemical analysis of the essential oil and various oleoresins of Elettaria cardamomum (seeds and pods) by gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) techniques. It also compares the effects of the different extraction solvents used (chloroform, methanol, ethanol and diethyl ether) on the antioxidant and antimicrobial activities of the essential oil and oleoresins. RESULTS: The essential oil was found to contain 71 compounds. The major components were α‐terpinyl acetate (44.3%), 1,8‐cineole (10.7%), α‐terpineol (9.8%) and linalool (8.6%). The chloroform and methanol oleoresins both contained α‐terpinyl acetate (21.8 and 25.9% respectively) as the main component, while 5‐hydroxymethylfurfural (28.9%) was the most abundant compound in the ethanol oleoresin. However, very few components (total 0.61%) were found in the diethyl ether oleoresin. The antioxidant activities of the essential oil and oleoresins, studied in mustard oil by monitoring the peroxide value of the oil substrate, were comparable to those of the synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) at 0.02% concentration. The essential oil exhibited strong antibacterial activity against the micro‐organisms Staphylococcus aureus, Bacillus cereus, Escherichia coli and Salmonella typhi at 3000 ppm by the agar well diffusion method. Antifungal activity was tested against the food‐borne fungi Aspergillus terreus, Penicillium purpurogenum, Fusarium graminearum and Penicillium madriti. The methanol and ethanol oleoresins gave the best results against A. terreus at 3000 ppm by the poison food method. CONCLUSION: This study provides important information about the chemistry and antioxidant and antimicrobial properties of E. cardamomum. Copyright © 2007 Society of Chemical Industry     

Antioxidant and antimicrobial activity of Satureja montana L. extracts

BACKGROUND: This study aimed to evaluate the antioxidant and antimicrobial activity of extracts (aqueous, ethanolic and essential oil) from Satureja montana and to characterise the chemical composition of its essential oil. RESULTS: Satureja montana L. essential oil had relatively high antimicrobial activities against the seven species of bacteria tested. In contrast, aqueous extracts did not reveal antibacterial activity, and the ethanol extract was not effective against Salmonella typhimurium. The major volatile constituents of the essential oil were carvacrol (306 g L^?1), thymol (141 g L^?1), and carvacrol methyl ether (63 g L^?1). The strongest antioxidant capacity was obtained with the hot water extracts of S. montana, whereas the plant essential oil revealed the highest phenolic content. CONCLUSION: The findings indicate that the bioactive extracts of S. montana have strong potential for use as natural antimicrobials and antioxidants in the preservation of processed food. Copyright © 2011 Society of Chemical Industry     

Chemical composition,antioxidative capacity and interactive antimicrobial potency of Satureja khuzestanica Jamzad essential oil and antimicrobial agents against selected food‐related microorganisms

This study aimed to determine the chemical composition, antimicrobial and antioxidative activity of Satureja khuzestanica Jamzad essential oil. The oil was analysed by GC and GC/MS. Twenty‐eight constituents were identified. The oxygenated monoterpenes (78.22%) were the principal compound group. Among them, carvacrol (53.86%) and thymol (19.84%) were the most abundant constituents. The oil exhibited an acceptable antimicrobial activity against most of the tested microorganisms. The checkerboard method was applied to determine fractional inhibitory concentration indices (FICIs) to interpret the synergetic, additive, indifference or antagonistic interactions between essential oil and each of antimicrobials (lysozyme, ciprofloxacin, fluconazole and amphotericin B) against food‐related microorganisms. The synergetic phenomenon (FICI ≤ 0.5) was observed in majority of combinations with the exception of the essential oil and lysozyme. The oil exhibited good 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity (IC₅₀ = 28.71 μg mL^?1). Also, the oil had strong antioxidative activity in β‐carotene‐linoleic acid assay relative antioxidant activity (RAA% = 95.45). This study demonstrated that the essential oil has beneficial biological properties and its simultaneous application with standard antimicrobials against food‐related microorganisms result in reduction in inhibitory doses of the antimicrobials in vitro.     

Antibacterial and antioxidant activities of the essential oil and methanol extracts of Bidens frondosa Linn

Antibacterial and antioxidant potential of essential oil, extract and its fractions of Bidens frondosa Linn were evaluated. Sixty‐one components representing 95.41% of the total oil were identified. The essential oil (7.5 μL disc^?1), methanol extract and its different organic subfractions (0.5 μg disc^?1) of B. frondosa displayed a great potential of antibacterial activity against Staphylococcus aureus (ATCC 6538 and KCTC 1916), Listeria monocytogenes ATCC 19116, Bacillus subtilis ATCC 6633, Pseudomonas aeruginosa KCTC 2004, Salmonella enteritidis KCTC 12021 and Enterobacter aerogenes KCTC 2190. Antioxidant activity was evaluated by using 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) assay. The free radical scavenging activity of ethyl acetate (EtOAc) fraction was superior to all other fractions (IC₅₀ = 11.96 μg mL^?1), which was higher than synthetic antioxidant butylated hydroxyanisole, (IC₅₀ = 18.27 μg mL^?1). Furthermore, the amount of total phenolic compounds was determined and its content in EtOAc fraction was the highest as compared to methanol extract or other fractions. The results indicate that the oil and extracts of B. frondosa could serve as an important bio‐resource of antimicrobial agents and antioxidants for using in the food industries.     

Antioxidant, antimicrobial and anticancer activities of three Parmelia species

BACKGROUND: Lichens are symbiotic organisms consisting of algae and fungi. They are used for human and animal nutrition and in the production of colours, perfumes and alcohol. Lichens have also been used in traditional medicine to treat diseases such as jaundice, pulmonary, stomach and cranial diseases. In this study the acetone extracts of three lichens, Parmelia caperata, Parmelia sulcata and Parmelia saxatilis, were tested for their antioxidant, antimicrobial and anticancer potential. RESULTS: Of the lichens tested, P. saxatilis had the highest free radical‐scavenging activity (55.3% inhibition). Moreover, all tested extracts showed effective reducing power and superoxide anion radical scavenging. Strong relationships between total phenolic and flavonoid contents and antioxidant effects of the tested extracts were observed. The extract of P. sulcata was most active in terms of antimicrobial ability, with minimum inhibitory concentration values ranging from 0.78 to 12.5 mg L^?1. All extracts were found to have strong anticancer activity, with IC₅₀ values ranging from 9.55 to 22.95 µg mL^?1. CONCLUSION: The present study showed that the tested lichen extracts exhibited strong antioxidant, antimicrobial and anticancer effects. This suggests that lichens may be used as possible natural antioxidant, antimicrobial and anticancer agents. Copyright © 2012 Society of Chemical Industry     

Mycotoxicogenic fungal inhibition by innovative cheese cover with aromatic plants

BACKGROUND: The use of aromatic plants and their extracts with antimicrobial properties may be compromised in the case of cheese, as some type of fungal starter is needed during its production. Penicillium verrucosum is considered a common cheese spoiler. The aim of this study was to evaluate the innovative use of certain aromatic plants as natural cheese covers in order to prevent mycotoxicogenic fungal growth (P. verrucosum). A collection of 12 essential oils (EOs) was obtained from various aromatic plants by solvent‐free microwave extraction technology, and volatile characterisation of the EOs was carried out by gas chromatography/mass spectrometry. RESULTS: The most effective EOs against P. verrucosum were obtained from Anethum graveolens, Hyssopus officinalis and Chamaemelum nobile, yielding 50% inhibition of fungal growth at concentration values lower than 0.02 µL mL^?1. All EOs showed high volatile heterogeneity, with α‐phellandrene, pinocamphone, isopinocamphone, α‐pinene, camphene, 1,8‐cineole, carvacrol and trans‐anethole being found to be statistically significant in the antifungal model. CONCLUSION: The use of these aromatic plants as natural covers on cheese can satisfactorily inhibit the growth of some mycotoxicogenic fungal spoilers. Among the volatile compounds present, α‐ and β‐phellandrene were confirmed as the most relevant in the inhibition. © 2012 Society of Chemical Industry     

Antioxidant activity of hydrolysates derived from porcine plasma

BACKGROUND: In China alone, more than 400 million pigs are slaughtered each year to provide meat. Porcine blood is rich in proteins but is usually discarded, which can cause environmental contamination. Recovering porcine blood and converting it to high‐value products is therefore economically and environmentally desirable. However, very little information on antioxidant peptides from porcine blood by‐products is currently available. In this study the antioxidant properties of porcine plasma hydrolysates PPE and PPA prepared with pepsin and papain respectively were investigated. RESULTS: Both PPE and PPA showed excellent antioxidant activity in a linoleic acid system (AL) compared with α‐tocopherol (VE) at the same concentration (P < 0.01). Their activities were respectively 3.33 and 1.83 times stronger than that of VE at a concentration of 10 µg mL^?1 and 5.4 and 5.6 times stronger at 100 µg mL^?1. The 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical‐scavenging activity (DRSA) reached 48.4 and 43.1% for PPE and PPA respectively at 500 µg mL^?1. The ferrous ion‐chelating power (FICP) of PPE at 100 µg mL^?1 was about 1.5 times stronger than that of 10 µmol L^?1 ethylene diamine tetraacetic acid (EDTA) in a 50 µmol L^?1 Fe²⁺ system, whereas the FICP of PPA at 100 µg mL^?1 was 61% that of 10 µmol L^?1 EDTA. Furthermore, PPE was separated on Resource 15RPC and Superdex peptide 10/300GL columns, and the antioxidant activity of the peptides and its relationship to their polarity and molecular weight (MW) were analysed. The hydrolysate was divided into four groups (R1–R4) with hydrophobicities ranging from weak to strong by Resource 15RPC, while it was divided into three groups (S1, MW 7–12 kDa; S2, MW 3–7 kDa; S3, MW 1–3 kDa) by Superdex peptide 10/300GL. CONCLUSION: The results showed that AL was significantly and positively correlated with the relative amounts of R1, S2 and S3 and that DRSA was dependent on R3 and S1. The fractions of PPE were not responsible for FICP. Copyright © 2009 Society of Chemical Industry     

Purification and characterisation of antioxidant and nitric oxide inhibitory peptides from Tilapia (Oreochromis niloticus) protein hydrolysate

Nitric oxide (NO)‐inhibitory and antioxidative activities of tilapia hydrolysates were prepared using ultrasound pretreatment at 70 W for 30 and 45 min, respectively, followed by Flavourzyme hydrolysis for 1 h. Both hydrolysates were fractionated using size exclusion chromatography on Sephadex G‐25 column and purified by RP‐HPLC. The amino acid sequence of the most potent and purified fractions was determined using LC/MS/MS. The antioxidant peptide (KAFAVIDQDKSGFIEEDELKLFLQNFSAGARAGDSDGDGKIGVDEFAALVK, MW: 6334.49 KDa) and NO‐inhibitory peptide (AFAVIDQDKSGFIEEDELKLFLQNFSAGARAGDSDGDGKIGVDEFAALVK, MW: 6309.49 Da) produced no cytotoxicity in RAW264.7 macrophage cell lines at the concentration of 100 mg mL^?1. The purified peptides at the concentration 100 μg mL^?1 possessed antioxidative and NO‐inhibitory activities 83.0 ± 1.1% and 40.9 ± 0.2%, respectively, which were about 100 times those of their counterpart crude hydrolysates.