Isolation and structure elucidation of phenolic compounds in Chinese olive (<Emphasis Type="Italic">Canarium album</Emphasis> L.) fruit

Chinese olive (Canarium album L.), one native and well-known tropical fruit tree in the southeast of China, contain a large amount of phenolics and possess great pharmacological activities. In this study, phenolics were extracted from Chinese olive fruit using 80% (v/v) aqueous acetone, and seven phenolic compounds were isolated and purified by Polyamide column and Toyopearl HW-40 column chromatography from crude extracts. Their structures were elucidated by high performance liquid chromatography coupled to diode array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI-MS), and where possible by ¹H NMR and ¹³C NMR spectrometry. Except gallic acid and hyperin, five phenolic compounds including methyl gallate, ethyl gallate, corilagin, kaempferol-3-glucoside and amentoflavone were first identified in Chinese olive.     

<Emphasis Type="Italic">Aronia melanocarpa</Emphasis> phenolics and their antioxidant activity

The purpose of the present study was to evaluate small and high molecular phenolics (tannins) and antioxidant activity of Aronia melanocarpa berries, juice and pomace in order to find new potential sources of natural antioxidants. The fruits of Aronia melanocarpa Elliot were collected in the middle of October at a plantation near Wroclaw, Poland. The pomace has a much higher content of phenolics in comparision to juice and fruits. Results showed that polymeric proanthocyanins, predominantly of (−)epicatechin, are the major class of polyphenolic compounds in chokeberry, represent 66% of fruits polyphenols. The average concentration ranged from 1578.79 mg/100 g of DW for chokeberry juice up to 8191.58 mg/100 g in pomace. The concentration of phenolic acids (chlorogenic and neochlorogenic acids) in juice was higher than in pomace. Anthocyanins in Aronia melanocarpa are second phenolic compound group and represent about 25% of total polyphenols, mixture of four different cyanidin glycosides: 3-galactoside, 3-glucoside, 3-arabinoside and 3-xyloside. The higher antioxidant activity expressed as TEAC was measured in pomace >fruit >juice.     

Investigations of the natural microflora of poppy seeds (<Emphasis Type="Italic">Papaver somniferum</Emphasis>) and hazelnut kernels (<Emphasis Type="Italic">Corylus avellana</Emphasis>) including microbiological decomposition

Fatty seeds of Papaver somniferum and Corylus avellana undergo a rapid microbial degradation after being ground. Those bacteria and fungi which are mainly responsible for the microbial decay were identified, and the most important growth and death processes were documented using crucial indicator-organisms. Additionally, an aflatoxin-screening was carried out in order to assess the possible risk-potential of food intoxication. The acid value (indicator for free fatty acids) of poppy seeds and hazelnut kernels was determined during their fermentation in order to document the decomposition of triglycerides.In this study it could be proved that initially a natural decay of oil seeds is caused by bacteria, yeasts and mould fungi. After the bacteria died in the course of time, yeasts and mould fungi dominated the germ spectrum. Bacteria taking part in the degradation were identified as varieties of Staphylococcus xylosus, Enterobacteriaceae and coliforms. Yeasts were identified as Pichia burtonii, and the mould fungi are associated with the genus Alternaria.On account of the absence of the genus Aspergillus in the spectrum of mould fungi, no aflatoxin was produced.     

Antitumor activities of liposome-incorporated aqueous extracts of <Emphasis Type="Italic">Anodonta </Emphasis><Emphasis Type="Italic">woodiana</Emphasis> (Lea, 1834)

To acquire the effectiveness of oral treatments, aqueous extracts of Anodonta woodiana (HB) were incorporated into liposome and its antitumor activities evaluated in vivo. The HB-loaded liposomes (HBL) were prepared at a mean size of 14.85 μm by reverse-phase evaporation method. Referring to the maximum tolerated doses test, mice with orally administrated HBL, at a 3 g/kg body weight dosage, showed no obvious acute toxic sign. Furthermore, the tumoricidal activities of HBL against C26 murine colon carcinoma, Lewis lung tumor, human QGY hepatic carcinoma and MKN-45 gastric tumor were examined, respectively. In contrast to free HB, HBL possessed remarkable antitumor activity. Simultaneously, the effect of HBL was observed in a dose-dependent manner. For C26 murine colon carcinoma and Lewis lung tumor, the inhibitory ratios of HBL were 54.36 and 51.97% at a dose of 400 mg/kg, respectively. The suppression of tumor growth and the reduction in body weight were more pronounced in human QGY hepatic carcinoma and MKN-45 gastric tumors inoculated mice by treatment of HBL during 30 days. All these promising results implied that liposome-incorporated aqueous extracts of Anodonta woodiana had a more potential application as a natural antitumor and immunomodulator formulation.     

Identification of a new phenolic compound from Chinese olive (<Emphasis Type="Italic">Canarium album</Emphasis> L.) fruit

Chinese olive (Canarium album L.), a native and a well-known tropical fruit tree in the southeast of China, contains large amount of phenolics and possesses great pharmacological activities. In this study, phenolics were extracted from Chinese olive fruit pulp using 80% (v/v) aqueous acetone, and acetone extracts were further fractioned with petroleum ether, ethyl acetate and n-butanol sequentially. From n-butanol fraction, a new phenolic compound was isolated and purified through AB-8 adsorption resin column chromatography, polyamide column chromatography and TSK Toyopearl HW-40 (S) column chromatography, and the structure of the new compound was established as 3-O-galloyl quinic acid butyl ester by electrospray ionization mass spectrometry (ESI-MS), 1D- and 2D-NMR (DEPT, COSY, HMBC, HMQC) and UV–vis techniques.     

Effects of suni-bug (<Emphasis Type="Italic">Eurygaster</Emphasis> spp.) damage on size distribution of durum wheat (<Emphasis Type="Italic">Triticum durum</Emphasis> L.) proteins

Wholemeal samples were obtained from five durum wheat cultivars at two different bug (Eurygaster spp.) damage levels (medium and high damage). The samples were incubated (60 and 120 min) and used in size exclusion high performance liquid chromatography (SE-HPLC) analyses. The results showed that the amount of larger polymeric protein (TP1) and smaller polymeric protein (TP2) obtained from total (sodium dodecyl sulfate soluble) proteins decreased significantly in the bug-damaged samples, while the amount of total larger monomeric proteins (TP3) increased. The polymeric/monomeric protein ratio of all cultivars decreased at 60 min of incubation with increasing damage level. For all cultivars, the ratio of unextractable polymeric protein (UPP%) significantly decreased at 60 min of incubation except cv. Diyarbakir. The results suggested that bug protease caused depolymerization and/or disaggregation of polymeric proteins to lower their average molecular size. The changes in protein structure as determined using SE-HPLC supported by the decreases in gluten content and gluten index values which decreased with suni-bug damage. Deteriorative effects of bug damage on durum wheat quality were found to be quite similar to those on bread wheats.     

Production of biogenic amines by<Emphasis Type="Italic"> Morganella morganii</Emphasis>,<Emphasis Type="Italic"> Klebsiella pneumoniae</Emphasis> and<Emphasis Type="Italic"> Hafnia alvei</Emphasis> using a rapid HPLC method

The histidine decarboxylating activity and production of biogenic amines by Morganella morganii (NCIMB, 10466), Klebsiella pneumoniae (NCIMB, 673) and Hafnia alvei (NCIMB, 11999) were investigated using a rapid HPLC method. Derivatisation of the bacterial samples was carried out using benzoyl chloride. A gradient elution system was used for analysis with a mixture of acetonitrile and HPLC grade water. Bacterial strains not only produce histamine in histidine-enriched broth but also the other biogenic amines. The chromatographic results show that bacterial strains are also capable of producing spermine and spermidine in histidine-enriched broth. Bacterial ammonia production by all three strains was clearly detected since ammonia is generated during the degradation of histidine. The study demonstrates that the highest histamine production was obtained by Morganella morganii, followed by Klebsiella pneumoniae, and the lowest with the Hafnia alvei. Therefore, Morganella morganii and Klebsiella pneumoniae have strong histidine decarboxylase activity since they are prolific histamine-forming bacteria     

Antioxidant activity of <Emphasis Type="Italic">Dioscorea batatas</Emphasis> Decne glycoprotein

Dioscorea batatas Decne (DBD) has been traditionally used as folk medicine and health food in Korea. One glycoprotein was isolated from DBD and confirmed to have 30 kDa molecular weight. The DBD glycoprotein was tested its antioxidative activity and characterized in various chemical conditions. The DBD glycoprotein has the optimal free radical scavenging activities in acidic and neutral pH and up to 85 °C. In the M²⁺ ions (Ca²⁺, Mn²⁺, and Mg²⁺) in the presence of EDTA, the activities of DBD glycoprotein reduced, compared to DBD glycoprotein alone without metal ion. Interestingly, the results in this study indicated that the activities of DBD glycoprotein do not depend on the presence of EDTA. Interestingly, when DBD glycoprotein was treated with deactivation agents (pronase E or NaIO₄), scavenging activity of DBD glycoprotein was decreased. The anti-oxidative effects of DBD glycoprotein on hydroxyl radicals in cell-free system revealed, and the DBD glycoprotein has remarkable scavenging effects on hydroxyl radicals generated by G/GO. Furthermore, the results in this study showed that the DBD glycoprotein (200 μg/ml) significantly inhibits intracellular ROS amounts and protects from cytotoxicity in primary mouse splenocyte culture treated with GO (30 mU/ml). Therefore, we speculate that DBD glycoprotein has an antioxidative potential as one of natural antioxidants.     

Antioxidant synergism between fruit juice and <Emphasis Type="Italic">α</Emphasis>-tocopherol. A comparison between high phenolic black chokeberry (<Emphasis Type="Italic">Aronia melanocarpa</Emphasis>) and high ascorbic blackcurrant (<Emphasis Type="Italic">Ribes nigrum</Emphasis>)

Black chokeberry juice (Aronia melanocarpa, Elliot), blackcurrant juice (Ribes nigrum, Ben Lomond) and α-tocopherol were found to protect phosphatidyl choline against oxidation in a peroxidating liposome system as evidenced by lag phases for formation of conjugated dienes. When present together, black chokeberry juice and α-tocopherol showed a clear synergistic effect on the length of the lag phase, while effects of blackcurrant juice and α-tocopherol were additive. The concentration of total phenolics in black chokeberry juice was six times higher than in blackcurrant juice (gallic acid equivalents). Ascorbic acid corresponded to 1% of total phenolics in black chokeberry juice and 10% in blackcurrant juice. Based on the length of the lag phase, the phenolics present in black chokeberry were on an average, twice efficient as scavengers of lipid peroxyl radicals as phenolics in blackcurrant. Black chokeberry was by HPLC analysis of peroxidating liposomes, in contrast to blackcurrant, found to protect α-tocopherol efficiently against oxidation to the end of the lag phase. The phenolics present in black chokeberry juice were concluded to be more efficient in regenerating or protecting α-tocopherol than ascorbic acid or the phenolics in blackcurrant. As for the phenolics, this was further evidenced by ranking of their radical scavenging activity as studied by ESR-spectroscopy.     

Modeling high pressure inactivation of <Emphasis Type="Italic">Escherichia coli</Emphasis> and <Emphasis Type="Italic">Listeria innocua</Emphasis> in whole milk

The survival curves of Escherichia coli and Listeria innocua inactivated by high hydrostatic pressure (HHP) were obtained at room temperature (∼22 °C) and at five pressure levels (400, 450, 500, 550 and 600 MPa) in whole milk. These curves were described by the Weibull model and parameters of this model were reduced from two to one with slight loss of goodness-of-fit. The logarithm of the time constant parameter (δ) of the reduced Weibull model was described with respect to high pressure (P). This approach can be used to define a z _p value analogous to the modeling of the classical D value (increase in pressure that results in one log unit decrease of δ values). The development of accurate survival models under high pressure, as presented here, can be very beneficial to food industry for designing, evaluating and optimizing HHP processes as a new preservation technology.     

Lactic acid fermentation of<Emphasis Type="Italic"> Brassica rapa</Emphasis>: chemical and microbial evaluation of a typical Italian product (<Emphasis Type="Italic">brovada</Emphasis>)

Brovada is an ancient traditional product from the northeast Italian region, included in any list of typical Italian products, which is obtained by natural fermentation of turnips (Brassica rapa). Turnips are cleaned and put in vats, alternating them with a layer of grape skins. Before covering the vat a mix of water and salt or water only is added. The vegetable fermentation is a spontaneous process caused by the microorganisms present on the various components (turnip and grape skins). A total 225 lactic acid bacteria (LAB) and 63 yeasts were isolated during this natural fermentation process. The main heterofermentative population was identified as Lactobacillus spp. while the major homofermentative LAB were Pediococcus spp., Candida spp. was the main yeast present. During the first 24 h of fermentation, the pH decreased rapidly to 3.7. At different steps of fermentation the headspace aroma compounds of brovada were analyzed by solid-phase-micro-extraction/gas chromatography/flame ionization detection to define the characteristic aroma profile of this particular product.     

Quality characteristics of different red pepper cultivars (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) for hot paprika production

Twelve hybrids obtained by crossing of different Hungarian cultivars and the Spanish ‘Jaranda’, ‘Jariza’ and ‘Jeromín’ have been studied. The aim of this work was to select those peppers with high capsaicinoids content, and good agronomic and industrial characteristics, as ‘Jeromín’, the only local cultivar used for pungent (hot) paprika, has a low and irregular pungency depending on the year. The crop productive characteristics, ASTA colour, carotenoid pigment content and pungency of the paprika has been studied and elaborated following the traditional procedure of La Vera (Extremadura, Spain). The productive characteristics and pigment concentration of the crossings were, in general, similar to that of local cultivars, and all of them could be suitable for hot paprika production, because their capsaicinoid content was higher than that of ‘Jeromín’ (78 mg kg⁻¹ dwt of total capsaicinoids). The most pungent hybrids were Kibedicsipos × Jariza, Jeromín × Szegedi178 and Jaranda × Szegedi179, with a total capsaicinoid content of 1,240, 1,107, and 997 mg kg⁻¹ dwt, respectively. Their paprikas showed a carotenoid pigment content higher than that of ‘Jaranda’, which is considered as a high quality paprika.     

Genotypic variation of mineral elements contents in rice (<Emphasis Type="Italic">Oryza sativa</Emphasis> L.)

Mineral nutrition of potassium (K), calcium (Ca), sodium (Na), magnesium (Mg), iron (Fe), zinc (Zn), copper (Cu) and manganese (Mn) are important for human health. The method of inductively coupled plasma mass spectrometry (ICP-MS) was employed to determinate the contents of K, Ca, Na, Mg, Fe, Zn, Cu and Mn in milled rice (Oryza sativa L.) of 274 rice genotypes. The results showed that the visible difference could be found for the contents of eight elements in milled rice among rice genotypes studied. It existed the possibility to select the genotype(s) with abundant of mineral nutrient from the genetic resource. Meanwhile, the contents of mineral elements in brown rice were significantly higher than those in milled rice. The averages of K, Mn and Cu contents of indica rice were significantly lower than those of japonica rice, while no significant difference was found for other five element contents between indica and japonica rice genotypes. The average contents of Na and Cu in non-glutinous rice genotypes were higher than those in glutinous ones, whereas the averages of K and Mn contents in non-glutinous rice genotypes were lower in present experiment. Additionally, the K, Ca and Mg contents of milled rice from white brown rice were significantly higher than those from red brown rice, and Ca content of milled rice from white brown rice was also visibly higher than that from black brown rice. For microelements, significant difference was observed for Zn content between milled rice from red and white brown rice, or between milled rice from red and black brown rice. Some genotypes with abundant mineral nutrient in milled rice had been selected and could be used in rice nutrient breeding.     

Efficiency of pulse pressure treatment for inactivation of <Emphasis Type="Italic">Escherichia coli</Emphasis> and <Emphasis Type="Italic">Listeria innocua</Emphasis> in whole milk

Escherichia coli ATCC 11775 and Listeria innocua ATCC 33090 in whole milk were inactivated by single- and multi-pulsed (up to 10 pulses) high hydrostatic pressure (HHP) treatments. Both bacteria showed similar resistance to single- and multi-pulsed HHP. The efficiency of pulsed pressure treatment depends on the combination of holding time of each pulse and number of pulses. It was observed that multi-pulsed pressure treatment instead of traditional single-pulsed HHP could be used to pasteurize milk at a lower pressure level. Nevertheless, an optimization is necessary between the pulse holding time, number of pulses, and pressure levels to reach the desirable log-reduction of microorganisms compatible with industrial application. This study was partly presented in Joint 21st AIRAPT and 45th EHPRG International Conference on High Pressure Science and Technology held September 17–21, 2007 in Catania (Italy).     

Detection and quantification of melatonin and serotonin in eight Sweet Cherry cultivars (<Emphasis Type="Italic">Prunus avium</Emphasis> L.)

Melatonin functions as a free radical scavenger and controls the regulation of the sleep–wake cycle in mammals, while serotonin is the main intermediate in melatonin biosynthesis. In this paper, melatonin and serotonin have been detected and quantified for the first time in eight different sweet cherry cultivars using high performance liquid chromatography with mass spectrometry detection. The limits of detection of the proposed analytical method were 4.3 ng/mL for melatonin and 3.0 ng/mL for serotonin. An inverse relation between the contents of melatonin and serotonin was observed in the studied sweet cherry cultivars. The highest melatonin amounts were found in ‘Burlat’ sweet cherries (22.4 ± 1.3 ng/100 g of fresh fruit), while the highest serotonin contents were found in the cultivar ‘Ambrunés’ (37.6 ± 1.4 ng/100 g of fresh fruit). The results presented in this research allow us to know the amount of melatonin and serotonin bring to the diet.     

Phenolic compounds in Imburana (<Emphasis Type="Italic">Amburana cearensis)</Emphasis> powder extracts

In response to the increasing demand for aged distilled spirits, wood extracts have been investigated as accelerating agents in distilled spirits. The aim of this work was to obtain and to evaluate the potential use of Amburana cearensis powder extracts as an accelerating aging agent in sugar cane distilled spirits. Wood powder was submitted to different toasting treatments using conventional drying oven and microwave oven. Instead of using the traditional reflux extraction method, the phenolic compounds were extracted by means of ultrasonic treatment using a 50% ethanolic solution with pH adjusted to 4.5. The concentration of gallic acid, 5-hydroxymethylfurfural, furfural, vanillic acid, syringic acid, vanillin, coniferaldehyde, sinapaldehyde and coumarin, determined by high performance liquid chromatography (HPLC) were used as quality parameters of powder toasting treatment and ethanolic extraction. The use of toasted wood powder combined with ultrasonic extraction showed higher yields when compared to the traditional solvent extraction method when obtaining wood extracts. The extraction method presented in this work is also less time consuming.     

Optimization of a process for enzyme-assisted pigment extraction from grape (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L.) pomace

A process for enzyme-assisted extraction of polyphenols from grape pomace was developed on laboratory and pilot-plant scale. After resuspending grape pomace in water, the skins were ground and the resulting mash was pasteurized to inactivate the deteriorative enzymes responsible for polyphenol degradation, and then pre-extracted with hot water. Subsequently, cell wall polysaccharides were hydrolyzed. The extract was separated from the solid residue by pressing, and finally spray dried. Before scaling-up, enzymatic hydrolysis was optimized on laboratory scale using a D-optimal design and analyzed by response surface methodology. A mixture of pectinolytic and cellulolytic enzyme preparations (ratio 2:1) yielded the highest amounts of phenolic compounds after 2 h of treatment, applying a dosage of 4,500 mg/kg (based on dry matter) at T = 40 °C and pH 4.0. Aqueous pre-extraction of the pomace followed by enzymatic treatment resulted in significantly improved extraction yields reaching 91.9, 92.4, and 63.6% for phenolic acids, non-anthocyanin flavonoids and anthocyanins, respectively. As the yields obtained were comparable to those from sulfite-assisted extraction, this process can be considered a suitable alternative to the application of sulfite.     

Analysis and the potential applications of essential oil and leaf extracts of <Emphasis Type="Italic">Silene armeria</Emphasis> L. to control food spoilage and food-borne pathogens

The aim of this study was to analyze the chemical composition of essential oil isolated from the floral parts of Silene armeria L. by hydrodistillation and to test the efficacy of essential oil and the various leaf extracts against a diverse range of microorganisms comprising food spoilage and food-borne pathogenic bacteria. The chemical composition of essential oil was analyzed by the GC–MS. It was determined that 28 compounds, which represented 89.03% of total oil, were present in the oil. The oil contained mainly methylamine (21.48%), β-butene (17.97%), α-butene (46.40%), coumaran (0.22%), eugenol (0.21%), α-humulene (0.07%), farnesol (0.05%) and linalool (0.12%). The essential oil (5 μl/ml, corresponding to 1,000 ppm/disc) and various leaf extracts of methanol, ethyl acetate, chloroform and hexane (7.5 μl/ml, corresponding to 1,500 ppm/disc) exhibited promising antibacterial effect against Bacillus subtilis ATCC6633, Listeria monocytogenes ATCC19166, Staphylococcus aureus KCTC1916, S. aureus ATCC6538, Pseudomonas aeruginosa KCTC2004, Salmonella typhimurium KCTC2515, Salmonella enteritidis KCTC2021, Escherichia coli O157-Human, E. coli ATCC8739, E. coli O57:H7 ATCC43888 and Enterobacter aerogenes KCTC2190. The zones of inhibition of different concentrations of essential oil and the various leaf extracts against the tested bacterial pathogens were found in the range of 10–19 and 7–13 mm, respectively, along with their respective MIC values ranging from 125 to 1,000 and 250–2,000 μg/ml. Also, the essential oil had a potential effect on the viable count of the tested bacteria. The results of this study suggest that the essential oil and leaf extracts derived from S. armeria could be used for the development of novel types of antibacterial agents to control food spoilage and food-borne pathogens.     

Effect of different technological processes on the chemical composition of myrtle (<Emphasis Type="Italic">Myrtus communis</Emphasis> L.) alcoholic extracts

Several technological processes were applied to improve the extraction efficiency in the production of myrtle (Myrtus communis L.) liqueur. The variations in the chemical composition of myrtle hydroalcoholic extracts were monitored in a laboratory scale for 40 days after the application of: double dose of berries; ultrasonic extraction; enzymes, to improve either the color or aroma extraction; and atmosphere saturated with nitrogen to improve the stability against oxidative degradations during extraction. Moreover, freezing at −20 °C was applied to myrtle berries as a technological strategy to prolong the use of berries, and macerates were obtained after 4, 8, and 12 months. Chemical investigation of macerates was performed using different analytical methods such as GC and GC-MS for the volatile compounds, HPLC-PDA for free anthocyanins, and spectrophotometric analysis for CIE L*a*b* coordinates and total anthocyanins. Dry matter and pH were also monitored during maceration. Among the different technological processes, the nitrogen-modified atmosphere was the most suitable technique to be applied in industrial scale. An industrial trial was applied with this process and alcoholic extracts and liqueurs have been obtained. The liqueur maintained a higher amount of anthocyanins, better CIE L*a*b* parameters and superior organoleptic characteristics compared to the traditional storage.