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1.
Four types of meju were made from 100%(w/w) defatted soybean (DFS), a mixture of 80%(w/w) defatted soybean, and 20%(w/w) glasswort (DFS-G), a mixture of 80%(w/w) defatted soybean and 20%(w/w) rice (DFS-R), and a mixture of 60%(w/w) defatted soybean, 20%(w/w) glasswort, and 20%(w/w) rice (DFS-GR). Four types of Korean traditional soy sauce were prepared from the 4 types of meju. Mineral and antioxidant contents in the soy sauce made of DFS-G and DFS-GR were significantly higher than others. Citric, malic, succinic, lactic, and pyroglutamic acid contents in soy sauce made of DFS-R and DFS-GR were 1.3–1.5 times higher than others. Total nitrogen and free amino acid contents in soy sauce were correlated with DFS concentration in the meju. The bacterial community in the non-fermented meju-making ingredients was replaced largely by Bacillus sp. in the fermented meju. The use of glasswort and rice in the meju-making process did not alter the bacterial community responsible for the fermentation of meju.  相似文献   

2.
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.  相似文献   

3.
The total phenolic compounds and flavonoid contents of grains as well as the antioxidant capacities were determined in 15 rice varieties. A high-performance liquid chromatography method was modified for the determination of the flavonoid subgroups in rice grains. The results showed the total phenolic compounds, flavonoid contents, and antioxidant capacities of pigmented rice were higher than in non-pigmented rice. The amounts of flavanone groups ranging from 0.04 to 0.40 mg Naringenin g?1, while flavones groups ranging from 0.08 to 0.57 mg Apigenin g?1, flavonol groups ranging from 0.16 to 1.20 mg Quercetin g?1 and anthocyanin groups ranging from 44.43 to 69.83 mg Cyanidin chloride g?1 were found in pigmented rice. The total phenolic compounds and total flavonoid contents of grains were significantly correlated with their antioxidant capacities. The results indicated that pigmented rice appeared as a good source of phenolic and flavonoid compounds and had beneficial nutritive values or antioxidant substances.  相似文献   

4.
This study aimed to identify the effects of soaking time and fermentation temperature and period on the total phenolics, total flavonoids, and antioxidant activity of maesil extract. Green maesil fruits were fermented with brown sugar at 15 or 25°C for one year. After soaking maesil for 90 days, the fruits were removed and the remaining liquid was further ripened for 275 days, whereas other samples continued to ferment with maesil until 365 days. Total phenolics, total flavonoids, and antioxidant activities of the extracts fermented with maesil for one year were higher compared with those wherein the fruits were removed at day 90. The total phenolic and total flavonoid contents were relatively higher at 15°C, whereas the ABTS and ferric-reducing antioxidant power (FRAP) activities were significantly higher at 25°C. The total phenolic and total flavonoid contents highly correlated with the antioxidant activities. These results show that fermentation temperature plays a critical role in enhancing the phenolic compounds and antioxidant activity of maesil extract.  相似文献   

5.
6.
Response surface methodology was used to predict optimum conditions for hot air roasting of barley grains (temperature, time, and amount). Antioxidant capacity in the grains was highest under optimum conditions of 250 °C, 63.5 min and 42 g (one and a half layers). A correlation of R 2 = 0.74 (p < 0.05) was found between 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic contents. Ethanol and aqueous extracts were prepared from grains roasted under optimum conditions and assessed for antioxidant capacity. Antioxidative compounds in the extracts were then identified using GC–MS. The IC50 value of ethanol extract was significantly lower (11.45 μg mL–1) than that of aqueous extract (33.54 μg mL–1) and α-tocopherol (12.6 μg mL–1) but higher than BHT (9.59 μg mL–1). The same trend was observed in linoleic acid assay. In reducing power, the ethanol extract and α-tocopherol were not significantly different. Phenolic acids p-hydroxybenzaldehyde, vallinic and gallic acids were identified as the major compounds in the extracts. The results obtained from this study show that it is possible to optimize antioxidant capacity in barley grains during roasting.  相似文献   

7.
Three varieties of Nigerian rice grains: CISADANE, OS6 and NERICA 19 were processed to obtain flours and starches. They were evaluated for their proximate composition and physicochemical properties. The grain physical dimension measurements showed that the CISADANE was slender while OS6 and NERICA 19 were bold and thick. The 1,000 grain weight was highest for CISADANE rice followed by OS6 and NERICA 19. CISADANE had the highest protein and amylose contents. Protein contents in samples ranged as follows: 5.6–6.7, 5.2–6.9 and 0.2–0.9 % in brown rice, milled rice and the rice starches, respectively. The amylose content of CISADANE (27.7–36.5 %) and OS6 (19.9–25.6 %) were high compared with NERICA 19 with negligible amylose. Swelling power and solubility generally increased with increasing temperatures (60–90 °C) for all the samples. Cooked CISADANE grain was hardest and OS6 (Faro 11) rice was softest while the stickiness was highest in OS6.  相似文献   

8.
The aim of this paper was to study the biogenic amines (histamine, tyramine, putrescine, cadaverine, agmatine, spermine and spermidine) production of selected technological important lactic acid bacteria (strains of the genera Lactococcus, Lactobacillus and Streptococcus). Three methods (ion-exchange chromatography (IEC), PCR and cultivation method with pH indicator) were used. Within the 39 strains of lactic acid bacteria tested, the production of tyramine (formed by tyrosine decarboxylase) was detected in eight strains (3 strains of Lactococcus lactis subsp. lactis, three strains of Lactococcus lactis subsp. cremoris, 1 strain of Streptococcus thermophilus and 1 strain of Lactobacillus delbrueckii subsp. bulgaricus). The other tested biogenic amines were not detected. Cultivation in decarboxylation broth seems to be the least accurate method for the detection of biogenic amines due to enhanced risk of false-positive reactions. Therefore, in order to detect bacteria producing biogenic amines, the combination of PCR and chromatographic methods (e.g. IEC) can be recommended.  相似文献   

9.
The various extracts from chamdanggui (Angelica gigas Nakai) and sogdan (Phlomis umbrosa Turcz) were evaluated for estrogenic activity and characterized according to HPLC profile. Chamdanggui and sogdan were individually extracted with 4 solvents (hot water, 70% ethanol, n-butanol, and dichloromethane) of differing polarities. Estrogenic activity was determined by E-screen using an estrogen-dependent MCF-7 BUS cell. Although almost all extracts showed estrogenic effects in a concentrationdependent manner, the hot water extract from chamdanggui (250 μg/mL) had the higher effect (138%). Among 90 fractions using HPLC separation of the hot water extract from chamdanggui, fraction 21 and 28 produced the highest estrogenic effects of 178 and 163% at 10 μg/mL, respectively. The results imply that the hot water extract from chamdanggui could be useful as an alternative hormone replacement therapy.  相似文献   

10.
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.  相似文献   

11.
Green tea has been credited with providing a wide variety of health benefits like higher total antioxidant, cancer prevention, and anti-irritant etc. Microencapsulation technology is used to prevent antioxidant loss during processing which involves entrapment of active material into carrier material. The experiments were designed using response surface methodology based on three level two factor (green tea extract, 10–25 % and drying inlet air temperature, 120, 130 and 140°C) central composite design. The feed emulsion was prepared with green tea extract as core material and 40 % maltodextrin concentration as wall material with the ratio of core to wall (1:2) and it was fed into the spray dryer at varied drying inlet air temperature to get encapsulated green tea extract powder. The quality characteristics were analysed such as moisture content, total antioxidant activity and total phenolic content and the process conditions were optimized using desirability function methodology. At optimum spray drying condition moisture content, total antioxidant activity and total phenolic content were found to be 3.1 % w.b., 72.91 % free radical scavenging activity by DPPH method, 57.81 mg/g of dry matter, expressed as gallic acid equivalent respectively with desirability value of 0.92.  相似文献   

12.
A new rapid method based on real-time PCR was developed to detect four thermophilic Campylobacter species (Campylobacter jejuni, Campylobacter coli, Campylobacter lari, and Campylobacter upsaliensis) in food samples. The assay targeted the bipA gene for C. upsaliensis and C. lari, whereas the gene encoding the ATP-binding protein CJE0832 was used to detect C. coli and C. jejuni. These genes were chosen for this assay due to their low variability and mutation rate at a species level. The multiplex PCR showed 100% inclusivity for all 25 thermophilic Campylobacter strains tested and 100% exclusivity for 38 non-targeted strains belonging to closely related species. The newly developed real-time PCR could detect down to 102 genomes/reaction and displayed efficiency above 97% for all species except for C. upsaliensis (90.1%). The method proved to be a reliable tool for food analysis, showing 100% sensitivity, 96% efficiency, and 92.45% specificity when validated against the gold standard method UNE-EN ISO 10272:2006 using 200 diverse food samples (meat, fish, fruits and vegetables, and raw milk). In artificially spiked samples, the detection limit of the method was 10 cfu/g in salad, 5 cfu/g in turkey meat, and 1 cfu/g in the rest of meat samples tested. Consequently, the newly designed molecular tool represents a quick and safe alternative to obtain reliable results concerning the presence/absence of the main thermophilic Campylobacter in any food sample.  相似文献   

13.
The aim of this research was to investigate the levels of phenolic compounds and antioxidant activities in different tissues including leaves, stems, and roots from baekseohyang (Daphne kiusiana). The highest contents of total phenolics (43.59 mg gallic acid equivalent, GAE/g) and flavonoids (15.73 mg rutin equivalents, RE/g) were observed in the 75% methanol extract of leaves. Moreover, this extract had the predominant antioxidant capacity, DPPH (85.91%) and ABTS (92.57%) radical scavenging activities as well as reducing power (7.20%) at a concentration of 5 mg/mL. The highest content of phenolic compounds was also exhibited in this extract with an increasing order in leaves, roots, and stems and their major components were vanillic acid (6.37 mg/g), tannic acid (1.91 mg/g), and p-hydroxybenzoic acid (3.96 mg/g). Thus, the strong antioxidant activities of the 75% methanol extract are correlated with high phenolic compound contents. This study suggests that baekseohyang leaves may potentially be used as an accessible source of natural antioxidants.  相似文献   

14.
Thermal inactivation of quality-related enzymes in both cauliflower crude enzyme extracts and fresh tissue samples was studied in temperature range 50–100 °C. For crude enzyme extracts, several parameters, reaction rate constants (k) and activation energy (E a) as well as decimal reduction time (D) and (z) values, were used to characterize the thermal stability. The rates of inactivation were found to follow first-order inactivation kinetics. Activation energies varied between 101.18 and 208.42 kJ mol−1 with z values of 10.59–24.09 °C. The examined kinetics indicated that lipoxygenase was the most heat resistant followed by peroxidase, polyphenol oxidase, pectin methyl esterase and ascorbic acid oxidase. Furthermore, the obtained results from the blanched fresh tissues indicated that inactivation of lipoxygenase secured disappearing of any other enzyme activities. Therefore, this study recommends using lipoxygenase as an indicator enzyme to optimize the thermal treatments of cauliflower products.  相似文献   

15.
Pigment composition of 15 black carrot cultivars (Daucus carota ssp. sativus var. atrorubens Alef.) was screened by HPLC-MS. Up to seven cyanidin glycosides, five of which were acylated with hydroxycinnamic and hydroxybenzoic acids, were identified and quantified in the roots by HPLC-DAD. Contents of individual compounds indicated great differences in the potential of anthocyanin accumulation both between different cultivars and carrots of the same cultivar. Total anthocyanin amounts ranged from 45.4 mg/kg dry matter to 17.4 g/kg dry matter. To the best of our knowledge, this is the first report on the quantification of individual anthocyanins in roots of different black carrot cultivars. The determination of color properties in the extracts under various pH conditions proved black carrot anthocyanins to be applicable as natural food colorants also for low-acid food commodities, whereas a considerable loss of color was noted under nearly neutral conditions. Additionally, relatively high saccharide contents were found in almost all cultivars which may be disadvantageous when coloring concentrates are produced from carrot roots.  相似文献   

16.
A Box–Behnken design (Extraction-time, pulse-cycle, sonication-amplitude) was employed to extract phenolic compounds from Justicia spicigera leaves by ultrasonic-assisted extraction. The muicle leaves extracts were analyzed measuring total phenolic compounds and antioxidant capacity. According to response surface methodology the optimal conditions of ultrasonic-assisted extraction to obtain the highest soluble phenolic content were 2 min (extraction time) for 0.7 s (pulse cycle) at 55% of sonication amplitude. Under these optimal conditions, the total phenolic content was higher when was used ultrasonic-assisted extraction (54.02 mg/g) than stirring (46.46 mg/g) and thermal decoction (47.76 mg/g); however, the antioxidant capacity from J. spicigera extracts did not increase by ultrasonic-assisted extraction. The extracts or aqueous infusions from J. spicigera leaves are used for therapeutic proposes, therefore the ultrasonic-assisted extraction is a useful technology to improve the extraction of phytochemicals from J. spicigera leaves.  相似文献   

17.
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.  相似文献   

18.
Food allergy has becoming the serious threat in the world for which the search of an effective anti-allergic drug is the demand of time. Keeping in view of the potentiality of seaweeds, the ethanol extracts from Sargassum tenerrimum (ST), Sargassum cervicorne (SC), and Sargassum graminifolium turn (SG) have been studied in vivo for its antiallergenicity through passive cutaneous anaphylaxis (PCA) and active cutaneous anaphylaxis (ACA) in female BALB/c mice. Intraperitoneal administration of these ethanol extracts inhibit mouse PCA and ACA in a dose-dependent manner using ovalbumin (OVA) and shrimp allergen as triggering agents to induce allergenicity over mice. The extract of ST containing phlorotannin has been found most active over the suppression of PCA triggered by OVA and shrimp with IC50 values of 25.64 and 40.98 mg/kg, respectively and an efficacy comparable to that of an anti-allergic drug disodiumcromoglycate. Similarly, ST inhibits ACA triggered by ova and shrimp allergen in the mouse, with 50% suppression at 25.5 and 43.53 mg/kg, respectively. The results presented here show that these extracts are active on the studied models among which ethanol extract of ST was the most potent, leading toward the promising development of a new class of anti-allergic drugs.  相似文献   

19.
To study the effect of fermentation on the antioxidant compounds and antioxidant capacity of Lupinus angustifolious cv. zapaton, two different types of fermentation processes were performed. Solid-state fermentations in cracked seeds carried out by Aspergillus oryzae, Rhizopus oryzae and Bacillus subtilis and liquid state fermentations in flour and cracked seeds carried out by the microbial population present in the seed (natural fermentation) or by L. plantarum inocula. Antioxidant compounds that were quantified included vitamin C by micellar electrokinetic capillary electrophoresis, vitamin E isomers by high performance liquid chromatography, total phenolic compounds (TPC) by spectrophotometry and reduced glutathione (GSH) by spectrofluorimetry. The antioxidant capacity was analysed by determining the superoxide dismutase-like activity (SOD-like activity), Peroxyl Radical-Trapping Capacity (PRTC) and Trolox Equivalent Antioxidant Capacity (TEAC) and by in vitro methods using unilamellar liposomes of egg yolk phosphatidylcholine (PC). In general, fermentation process produced a reduction in vitamin C, vitamin E activity, GSH and SOD-like activity, however TPC, PRTC, TEAC and inhibition of PC peroxidation increased under most of the fermentation conditions. Optimal results to obtain functional lupin products were achieved in cracked seeds fermented with B. subtilis where increases in TPC content, PRTC, inhibition of PC peroxidation and TEAC content of 490, 669, 492 and 224%, respectively, were found. Also, fermentation carried out with L. plantarum in lupin flours and naturally in cracked seeds caused smaller, although significant (P ≤ 0.05) increases in TPC, PRTC, inhibition of PC and TEAC (80–148, 50–90, 23 and 45–65%, respectively).  相似文献   

20.
The diversity of 87 Lactobacillus paracasei and Lactobacillus plantarum/paraplantarum strains, previously identified from different autochthonous dairy products, was investigated by phenotypic and genotypic approaches. The increased resolution obtained using phenotypic and genotypic characterization allowed the level of strain heterogeneity detection to be widened. Phenotypic diversity was evaluated by studying biochemical characteristics of technological interest, including antimicrobial and proteinase activities, resistance to nisin, aggregation ability, production of exopolysaccharides, acetoin and diacetyl, citrate utilization, and antibiotic susceptibility. Genotypic diversity was generally evaluated by PCR amplification of repetitive bacterial DNA element fingerprinting using the (GTG)5 primer [(GTG)5-PCR]. Moreover, in cases where strains were not discriminated by (GTG)5-PCR combined with phenotypic analysis, pulsed-field gel electrophoresis (PFGE) analysis was performed. The results indicate that L. plantarum/paraplantarum and L. paracasei natural isolates from artisanal dairy products are a gold mine in terms of diversity of strains and could be potentially interesting to dairy companies for the formulation of functional starter cultures in the production of innovative foods.  相似文献   

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