NATTO BACILLUS CONTAINS A LARGE AMOUNT OF WATER-SOLUBLE VITAMIN K (MENAQUINONE-7)

Bacillus natto (Bacillus subtilis natto) was cultivated, and an analysis was conducted after performing lysozyme treatment and water extraction of the culture supernatant and the B. subtilis natto cells. The intracellular existence of a large amount of water‐soluble vitamin K (Menaquinone‐7: MK‐7) was established. The existence of small amounts of other types of vitamin K2 including MK‐4 and PK was also confirmed in the culture solution (water‐soluble fractions). The amount of water‐soluble menaquinone‐7 in Bacillus was 85 µg/g wet weight of the bacteria, and the amount was equivalent to more than 100 times as much as that contained in the culture solution (0.02 µg). Gel filtration using Sephacryl S‐200HR revealed that the molecular weight of the water‐soluble menaquinone‐7 is approximately MW 200,000, and isoelectric focusing revealed a behavior similar to that of protein, with a pI of about 4.2. A rabbit antibody was prepared with this water‐soluble vitamin K as the antigen. By using the Ouchterlony method, the antibody showed a reaction (precipitation line) with the water‐soluble menaquinone‐7 prepared from both the intracellular fraction and the extracellular culture solution, and it was found through the antigen–antibody reaction that the menaquinone‐7 disappears from the supernatant of the reactant (the water‐soluble menaquinone‐7 is thus neutralized). Based on these results, it was inferred that the vitamin K produced by B. subtilis natto becomes water‐soluble by forming an intracellular complex with protein and is released in the extracellular fraction during the culture process.     

Polysaccharides from Enteromorpha tubulosa: Optimization of extraction and cytotoxicity

An ultrasound‐assisted procedure for the extraction of water‐soluble polysaccharides from Enteromorpha tubulosa was studied by using response surface methodology. Three independent variables including extraction time, extraction temperature, and ratio of liquid to raw material were investigated by single‐factor experiments. A three‐factor‐three‐level Box–Behnken design was adopted to optimize the extraction process parameters. A highly significant second‐order polynomial equation was fitted by using multiple regression analysis. The optimal extraction conditions were obtained as follows: extraction time 36 min; extraction temperature 69 °C; and ratio of liquid to raw material 45 mL/g. By experiments with these conditions, the extraction yield was 16.04%, which was well matched with the predicted value. The obtained polysaccharides were evaluated for cytotoxicity in vitro against human breast cancer cell line MCF‐7 and the results showed that the polysaccharides possessed potent cytotoxicity.

Practical applications

Seaweeds are one of the largest numbers and species of marine plants, and their bioactive compounds, especially algal polysaccharides, have become the focus of research in the field of food and medicine. Moreover, many algal polysaccharides have been gradually applied to food and medicine owing to their varied biological activities, such as antivirus, antitumor, antiradiation, antimutation, antioxidation, and enhancing immunity. However, there is no universal extraction process for polysaccharides from the different seaweeds because of the different structures of the seaweeds and the varying compositions of algal polysaccharides. In the current research, an ultrasound‐assisted procedure for the extraction of water‐soluble polysaccharides from Enteromorpha tubulosa was studied by using response surface methodology, and the optimal extraction conditions were obtained so as to provide references for the mass productions in the factories.     

Hot water bath treatments assisted by microwave energy to delay postharvest ripening and decay in strawberries (Fragaria × ananassa)

BACKGROUND: A lab‐scale approach using microwave (MW)‐assisted hot water treatments was developed and tested to assess the potential of this heating method to delay postharvest ripening and decay in strawberries. Strawberries (Fragaria × ananassa) immersed in water were exposed to microwaves at a frequency of 2450 MHz for 3 min at 514 W or 1 min 50 s at 763 W to reach an average temperature of 43.8 ± 0.6 °C at the fruit centre. Another batch was treated in hot water at 45 °C for 15 min, and a final batch was not treated (control). RESULTS: After 9 days of refrigerated storage (3 °C and 90% relative humidity), all heat‐treated strawberries showed significant retention of quality parameters such as colour and firmness and significantly lower yeast and mould populations (P < 0.05). CONCLUSION: Strawberries subjected to MW‐assisted hot water treatments showed significantly better retention of lightness compared with conventionally treated berries. A short (1 min 50 s) treatment at 763 W was the best choice to prevent strawberry decay. Copyright © 2011 Society of Chemical Industry     

The optimization of microwave-assisted extraction of decursin from Angelica gigas Nakai root

Response surface methodology was used to display the characteristics of microwave‐assisted extraction (MAE) of soluble solids and decursin from Angelica gigas Nakai root, thereby allowing MAE conditions to be optimized. These included ethanol concentration, microwave power and extraction time. The maximal solid yield was predicted to be 44.2% under conditions of 44.9% ethanol concentration, 115.6 W microwave power and 5.8 min extraction time. Decursin content of the extract was estimated to be maximal at 2.52% using 97.7% ethanol, 90.2 W microwave power, and 6.1 min extraction time. The estimated optimal MAE conditions (67% ethanol, 100 W and 6 min) to maximize both components were verified by comparing estimated values with experimental values (42.2% soluble solids, 2.2% decursin), which were higher than those (35.8% solids, 2.0% decursin) obtained by conventional reflux extraction (60% ethanol, 95 °C and 6 h).     

EFFECT OF PENTOSANASE ON DOUGH AND BREAD PROPERTIES PRODUCED BY DIFFERENT TYPES OF FLOURS

ABSTRACT

The effects of pentosanase at different doses (20, 60 and 100 ppm) on physical dough properties and bread quality were studied using three types of wheat flours. Flour A was a regular bread flour, flour B had a high hardness ratio and protein content, and flour C was prepared from the same blend of flour A but had a high extraction ratio. Regarding farinograph data, water absorption values of the high extraction (86%) flour C and high hardness (65%) blend flour B increased with introduction of pentosanase. Extensibility values of the flours increased moderately with pentosanase addition, while resistance and energy values decreased. The volume of breads made with flours C and B decreased upon addition of pentosanase. But loaf volume of breads prepared with regular bread flour A with 50% hardness and 76% extraction rate increased with high levels of pentosanase addition. In conclusion, flour A as a regular bread flour gave satisfactory results with pentosanase supplementations, whereas the harder‐blend (65%) and higher‐extraction‐rate (85%) flours from the same cultivars did not.

PRACTICAL APPLICATIONS

Pentosanase addition was more effective on soluble pentosans than on insoluble ones. Because of these effects, it enhanced the bread‐making properties of regular flour more effectively than those of the high‐extraction and harder‐blend flours of the same cultivars.

     

Ultrasound‐assisted extraction and characterization of anthocyanins from purple corn bran

Purple corn is abundant in anthocyanins, which has attractive colors and potential applications in beneficial health. This study aimed to determine the optimal ultrasound‐assisted extraction conditions for purple corn anthocyanins (PCA), and to confirm the anthocyanins from purple corn bran extracts by HPLC‐DAD‐ESI‐MS/MS. Ultrasonic‐assisted extraction (UAE) is more time‐efficient by comparison of traditional extraction. Meanwhile extraction with corn bran could save the consumption of extractant and improve the extraction yield. The optimal UAE conditions were obtained with the extraction time 35 min, the ultrasonic times 90, solid–liquid ratio 1:8, and the ultrasonic power 400 W. At these conditions, total anthocyanins content was determined as 3.625 ± 0.105 g kg^?1, and the extraction yield was 92.45%. The HPLC/MS‐MS results showed that the purple corn bran extracts consisted of six kinds of anthocyanins.

Practical applications

Purple corn is abundant in anthocyanins, which has potential applications in beneficial health, such as antioxidants. The purpose of this study was to find the optimal UAE conditions for purple corn anthocyanins using ultrasound‐assisted extraction and identify the anthocyanins from the purple corn bran. The results of this study are suitable for the industrial production of purple corn anthocyanins.     

Microwave‐assisted extraction of secoisolariciresinol diglucoside from flaxseed hull

Microwave‐assisted extraction (MAE) of secoisolariciresinol diglucoside (SDG) from defatted flaxseed hull (DFH) was studied. The effects of pre‐soaking methods and extraction parameters (ethanol concentration (0–100%, v/v), microwave energy input (50–390 W), liquid to solid ratio (5:1 to 40:1, mL g^?1) and irradiation time (10–330 s)) on the SDG yield were investigated. Response surface methodology (RSM) was applied to optimise the MAE conditions as irradiation time 90.5 s, ethanol concentration 40.9% (v/v), liquid to solid ratio 21.9:1 (mL g^?1) and microwave power 130 W. The SDG recovery from DFH with MAE was 11.7 g SECO kg^?1 DFH (on dry‐weight basis), which was significantly higher than that of stirring extraction (10.0 g SECO kg^?1 DFH) and Soxhlet extraction (7.60 g SECO kg^?1 DFH). Compared with stirring extraction and Soxhlet extraction, MAE showed its superiority in improving SDG yield and saving time and energy. Copyright © 2007 Society of Chemical Industry     

Microwave‐Assisted Extraction,Chemical Structures,and Chain Conformation of Polysaccharides from a Novel Cordyceps Sinensis Fungus UM01

Cordyceps sinensis is a well‐known tonic food with broad medicinal properties. The aim of the present study was to investigate the optimization of microwave‐assisted extraction (MAE) and characterize chemical structures and chain conformation of polysaccharides from a novel C. sinensis fungus UM01. Ion‐exchange and gel filtration chromatography were used to purify the polysaccharides. The chemical structure of purified polysaccharide was determined through gas chromatography‐mass spectrometry. Moreover, high performance size exclusion chromatography combined with refractive index detector and multiangle laser light scattering were conducted to analyze the molecular weight (M_w) and chain conformation of purified polysaccharide. Based on the orthogonal design L₉, optimal MAE conditions could be obtained through 1300 W of microwave power, with a 5‐min irradiation time at a solid to water ratio of 1:60, generating the highest extraction yield of 6.20%. Subsequently, the polysaccharide UM01‐S1 was purified. The UM01‐S1 is a glucan‐type polysaccharide with a (1→4)‐β‐d ‐glucosyl backbone and branching points located at O‐3 of Glcp with a terminal‐d ‐Glcp. The M_w, radius of gyration (R_g) and hydrodynamic radius (R_h) of UM01‐S1 were determined as 5.442 × 10⁶ Da, 21.8 and 20.2 nm, respectively. Using the polymer solution theory, the exponent (ν) value of the power law function was calculated as 0.38, and the shape factor (ρ = R_g/R_h) was 1.079, indicating that UM01‐S1 has a sphere‐like conformation with a branched structure in an aqueous solution. These results provide fundamental information for the future application of polysaccharides from cultured C. sinensis in health and functional food area.     

Effect of commercial enzymatic preparation with pectolytic activities on conventional extraction and ultrasound‐assisted extraction of oil from grape seed (Vitis vinifera L.)

Conventional solvent extraction (CE) and ultrasound‐assisted extraction (UAE) in hexane for oil from untreated and enzyme‐treated grape seeds were investigated and compared. Among the output power tested (50, 100 and 150 W) in UAE on untreated seeds, UAE at 150 W for 30 min with liquid‐to‐solid ratio 8:1 (v/w) gave oil extraction yield comparable to CE (ca. 14% w/w) for 6 h with liquid‐to‐solid ratio 12:1 (v/w). CE and UAE at 150 W did not influence the fatty acid profiles of oil. CE oil was found to be the most oxidised. The enzymatic treatments (2, 4 and 6 g per 100 g seeds of Rapidase^® Expression) prior to CE enhanced by 2.5% of the oil yield. Enzymatic treatments higher than 2 g per 100 g seeds increased relative value of some fatty acids both in CE and UAE. Enzymatic pretreatment from 2 to 4 g per 100 g seeds significantly improved some physicochemical parameters of oil quality when extracted by CE, but not by UAE.     

Optimised methodology for the extraction of protein from quinoa (Chenopodium quinoa Willd.)

Quinoa is a highly appreciated Andean pseudo‐cereal and has sparked attention worldwide due to its excellent nutritional value. The protein extraction parameters for defatted quinoa seed meal (DQSM) were optimised in this study. Initially, a Plackett–Burman design was applied to screen the factors displaying a potential effect on the quinoa protein extraction yield (Y %, g soluble protein/100 g total protein) being the main evaluated factors: pH, NaCl concentration, time, temperature, solvent type, particle size and solvent/meal ratio. Four main factors: temperature, solvent/meal ratio, pH and time selected from the screening step were optimised with a central composed design (CCD). The obtained response surface model (RSM) produced a satisfactory fitting of the results (R² = 0.9308). Optimal quinoa protein extraction conditions of 36.2 °C, solvent/meal ratio of 19.6/1 (v/w) and 90 min resulted in a protein yield of 62.1% (9.06 g of protein/100 g DQSM) which closely agree with the predicted value of 62.5%.The model was experimentally validated by extracting the quinoa protein using the optimal conditions revealed by RSM. The optimised conditions could be successfully employed in the design process of protein extraction from quinoa seed meal to obtain optimal yields.     

Studies on different combined microwave drying of carrot pieces

Three different combined microwave (MW) drying methods were compared, namely microwave‐assisted vacuum drying (MWVD), microwave‐assisted freeze drying (MWFD), microwave‐enhanced spouted bed drying (MWSD), in terms of drying rate, drying uniformity, product colour, rehydration ratio, retention of β‐carotene and vitamin C, and energy consumption. The drying rate of MWVD and MWSD were much faster than that of MWFD. The largest drying rate was obtained in MWSD with 3.5 W g^?1. In general, the colour of MWSD products was very uniform. Rehydration ratio of MWFD carrot pieces was almost the same as the freeze‐dried (FD) products and better than MWVD and MWSD products. In addition, the highest retention of carotene and vitamin C was observed in MWFD carrot pieces. No significant differences were observed in carotene and vitamin C between MWVD and MWSD products. However, the energy consumption in MWFD was the highest.     

Microwave‐assisted extraction and antioxidant activity of star anise oil from Illicium verum Hook.f

In this study, microwave‐assisted extraction with ethanol (MAEE) of star anise oil from Illicium verum Hook.f. has been optimised by response surface methodology (RSM). A maximum yield of star anise oil was obtained at an optimum condition: the ratio of solvent to sample 17 mL g^?1, extraction time 16 min and microwave power 505 W. Accordingly, the highest yield of star anise oil was about 24.98%, which was much higher than that of steam distillation (SD), 7.17%. Oxygenated organic compounds in representative of trans‐anethole are a major component in star anise oil, nearly 94.21% for SD and 86.66% for MAEE, identified and determined by GC‐MS. The oils extracted by SD and MAEE both have strong antioxidant activities that were demonstrated by the DPPH and ABTS assays.     

Mechanochemical‐assisted extraction and antioxidant activity of polysaccharides from Ganoderma lucidum spores

Mechanochemical‐assisted extraction (MCAE) method was developed to an effective method for polysaccharides extraction from Ganoderma lucidum spores. The MCAE parameters and the antioxidant activity of polysaccharides were investigated. Through response surface methodology design experiments, the processing conditions were optimised as follows: material/solid reagent (Na₂CO₃) 5 g·g^?1, milling time 20 min, solution/material ratio twenty (mL·g^?1) and extraction time 130 min. Under these conditions, the yield of polysaccharides was (5.92 ± 0.13)%, which was in close agreement with the predicted value. Compared with the heat‐reflux extraction method, the MCAE method had higher extraction yield, shorter extraction time and lower extraction temperature. In addition, the polysaccharides obtained from MCAE exhibit significant antioxidant activity.     

Antimicrobial and Antioxidant Activities of Cichorium Intybus Root Extract Using Orthogonal Matrix Design

Solvent, impregnation time, sonication repetitions, and ultrasonic power were important factors in the process of ultrasound‐assisted extraction from chicory (Cichorium intybus) root, while there were no studies about optimizing these 4 factors for extract yield, total phenolic content (TPC), antioxidant, antibacterial, and antifungal activity of the extracts using orthogonal matrix design. The present research demonstrated that the solvent composition played a significant role in the improving extract yield, TPC, antioxidant, and antibacterial activities. The other 3 factors had inequable effect on different purposes, ultrasonic power could improve TPC and antioxidant activity, but long time of extraction lowered antioxidant activity. The TPC increased from 22.34 to 27.87 mg GAE (gallic acid equivalents)/100 g (dry extracts) with increasing solvent polarity. The half inhibition concentration (IC_50, μg/mL) of the radical scavenging activity of the chicory extracts ranged from 281.00 to 983.33 μg/mL. The content of caffeoylquinic acids of root extract, which was extracted by the optimal combination was 0.104%. Several extracts displayed antibacterial activities against Escherichia coli, Staphylococcus aureus, Bacillus thuringiensis, Bacillus subtilis, and Salmonella typhi, while Penicillium sp. and Aspergillus sp. resisted against all the extracts. Combination of 70% ethanol v/v, 24‐h impregnation time, 3 sonication rounds, and 300‐W ultrasonic input power was found to be the optimal combination for the chicory extract yield, TPC, antioxidant activity, and antibacterial activity.     

笋壳多糖的微波-超声波联合辅助提取工艺优化及其抗氧化活性

目的：通过微波-超声波联合辅助提取法优化笋壳多糖提取工艺,并研究其抗氧化活性。方法：考察提取时间、料液比、微波功率、超声波功率、提取次数对笋壳多糖含量的影响,在单因素试验基础上做L9（34）正交试验优化提取工艺参数,通过测定笋壳多糖清除羟自由基、超氧阴离子自由基、1,1-二苯基-2-苦基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基的能力来评价其抗氧化活性,并同传统热水浸提法进行比较。结果：微波-超声波联合辅助提取最优工艺条件为提取时间30 min、料液比1∶30（g/mL）、微波功率200 W、超声波功率750 W,笋壳多糖得率为2.76%,粗多糖中多糖含量为37.63%;清除羟自由基、DPPH自由基和超氧阴离子自由基的半抑制浓度分别为0.17、0.43 mg/mL和大于16 mg/mL。微波-超声波联合辅助提取法的各项指标均优于热水浸提法。结论：微波-超声波联合辅助提取笋壳多糖比传统热水浸提具有耗时短、效率高等优点,笋壳水溶性多糖具有显著体外抗氧化活性。     

Optimisation of the microwave‐assisted extraction process for six phenolic compounds in Agaricus blazei murrill

An efficient microwave‐assisted extraction (MAE) technique was employed in the extraction of phenolic compounds from Agaricus blazei murrill, and phenolic compounds were quantified by High‐performance liquid chromatography (HPLC). The MAE procedure was optimised, validated and compared with other conventional extraction techniques. MAE gave the best result because of the highest extraction efficiency within the shortest extraction time. The optimal conditions of MAE were 60% ethanol, ratio of solid/liquid 1:30, temperature 110 °C, irradiation power 500 W and three extraction cycles, each 5 min. This is the first report on combining MAE with HPLC for the extraction and quantification of phenolic compounds in A. blazei murrill. The developed MAE method provided a good alternative for the extraction of phenolic compounds in A. blazei murrill as well as other materials.     

Effects of Green Tea Extract and α‐Tocopherol on the Lipid Oxidation Rate of Omega‐3 Oils,Incorporated into Table Spreads,Prepared using Multiple Emulsion Technology

Abstract: This study examined the effectiveness of fat and water soluble antioxidants on the oxidative stability of omega (ω)‐3 rich table spreads, produced using novel multiple emulsion technology. Table spreads were produced by dispersing an oil‐in‐water (O/W) emulsion (500 g/kg 85 camelina/15 fish oil blend) in a hardstock/rapeseed oil blend, using sodium caseinate and polyglycerol polyricinoleate as emulsifiers. The O/W and oil‐in‐water‐in‐oil (O/W/O) emulsions contained either a water soluble antioxidant (green tea extract [GTE]), an oil soluble antioxidant (α‐Tocopherol), or both. Spreads containing α‐Tocopherol had the highest lipid hydroperoxide values, whereas spreads containing GTE had the lowest (P < 0.05), during storage at 5 °C, while p‐Anisidine values did not differ significantly. Particle size was generally unaffected by antioxidant type (P < 0.05). Double emulsion (O/W/O) structures were clearly seen in confocal images of the spreads. By the end of storage, none of the spreads had significantly different G′ values. Firmness (Newtons) of all spreads generally increased during storage (P < 0.05). Practical Application: Lipid oxidation is a major problem in omega‐3 rich oils, and can cause off‐odors and off‐flavors. Double emulsion technology was used to produce omega‐3 enriched spreads (O/W/O emulsions), wherein the omega‐3 oil was incorporated into the inner oil phase, to protect it from lipid oxidation. Antioxidants were added to further protect the spreads by reducing lipid oxidation. Spreads produced had good oxidative stability and possessed functional (omega‐3 addition) properties.     

Physicochemical,rheological, and molecular characterization of colloidal gelatin produced from Common carp by‐products using microwave and ultrasound‐assisted extraction

The effects of ultrasound‐assisted extraction (UAE) and microwave‐assisted extraction (MAE) methods on molecular and physicochemical characteristics of the resultant gelatin were examined. Before extraction procedure, we investigated the optimum pH for swelling of Common carp by‐products, which is an important pretreatment for gelatin production. The highest swelling yield was achieved at pH 13 among pH 1–14 with unit intervals. Results indicated that the UAE gelatin has a higher gel strength, viscosity, melting point, and gelling point. The power and time of sonication showed a reverse relation with these characteristics. In addition, as the time of microwave heating was raised, the gel strength, viscosity, melting point, and gelling point were decreased. The FT‐IR spectra showed similar peaks but the Amide B in UAE gelatin slightly vanished. The electrophoretic pattern also revealed the higher gel strength and viscosity of UAE gelatin due to the higher intensity of α and β chains compared to MAE gelatin. It can be concluded from all of the results of this study that the produced gelatin using these procedures can be a good source of gelatin in food and drug industries.     

Ultrasound‐assisted extraction of ginsenosides in supercritical CO2 reverse microemulsions

Ultrasound‐assisted extraction of ginsenosides from ginseng in supercritical CO₂ reverse microemulsions formed by bis(2‐ethylhexyl) sodium sulfosuccinate (AOT) was studied. Prior to extraction the ginseng was soaked in water for 12 h. It was found that ultrasound significantly enhanced supercritical CO₂ reverse microemulsion extraction. The ginsenoside extraction yield from supercritical CO₂ reverse microemulsion with ultrasound of 20 kHz, 15.2 W cm^?2 and 3/6 s was 2.63 times that without ultrasound at 24 MPa extraction pressure, 45 °C extraction temperature, 4 h extraction time, 5 MPa separation pressure, 55 °C separation temperature and 2 L h^?1 CO₂ flow rate with 140 mL of 0.07 mol L^?1 AOT/ethanol. The maximum extraction yields of ginsenosides from different concentrations of reverse microemulsions were obtained at different ultrasonic intensities. The extraction yield with 20 kHz ultrasound was higher than that with 38 kHz ultrasound at suitably low intensity; however, it was lower at high intensity. The yield improvement may be basically attributed to the mechanical and thermal effects of ultrasound. Copyright © 2006 Society of Chemical Industry     

The effect of preultrasonic process on oil content and fatty acid composition of hazelnut,peanut and black cumin seeds

In this study, the effect of different sonication times (10, 20, and 30 min) on oil yields, extracted by using soxhlet together with preultrasonic treatment, and fatty acid composition of seed/kernels were investigated. The sonication of samples for 30 min caused the highest increase in oil yield of hazelnut (from 62.38 to 63.60%) and black cumin (from 27.90 to 31.80%) (p < .05). The appropriate sonication time for oil yield of peanut was 10 min, with the range of 51.50%. After sonication process, the dominant fatty acid contents of all samples showed a change and the major decrease in oleic acid amount of hazelnut (from 75.20 to 74.27%) and peanut oils (from 57.10 to 56.69%) and linoleic acid content of black cumin (from 58.38 to 57.50%) were determined when samples sonicated for 30 min (p < .05). Sonication process caused a decreasing in black cumin oil, and the reduction increased with sonication time.

Practical applications

Ultrasound‐assisted extraction method can be used as an alternative extraction method for conventional extraction. Ultrasonic‐assisted extraction has some advantages as being efficiency, speed and using low temperatures, which prevents thermal damage. The ultrasound process enables to greater influence of solvent into the sample matrix and increases mass transfer. Thereby, the higher extract yield, almost 23%, provided with ultrasonic‐assisted extraction in comparison to soxhlet extraction.