Purification and Concentration of the Total Saikosaponins Extracted from Radix Bupleuri using Foam Fractionation

The purpose of this study was to investigate the use of foam fractionation to recover saikosaponins. First, the solvent extraction method was applied for the extraction of saikosaponins from radix bupleuri using ethanol or deionized water. Then, the foam fractionation technique in batch mode was used for the recovery of the total saikosaponins from the extract. The effects of initial concentration, air flow rate, liquid loading volume, pH, and operating time on the process performance were investigated. The recovery percentage 77.2% and an enrichment ratio 3.68 of total saikosaponins with one-stage separation were obtained under the optimal conditions of initial saikosaponin concentration 0.18 mg/mL, air flow rate 50 mL/min, liquid loading volume 200 mL, pH 5.5, and operating time of 2 h. A two-stage foam fractionation technology was also designed, which was effective for improving both the recovery percentage and enrichment ratio simultaneously.     

Foam fractionation for effective recovery of leaf protein from alfalfa (Medicago sativa L.)

ABSTRACT

Foam fractionation for recovering leaf protein from alfalfa (Medicago sativa L.) has been investigated. The extraction yield of alfalfa leaf protein (ALP) from the dried alfalfa leaves reached 71.90% under the extraction conditions of pH 8.0, temperature 70°C, and extracting time 40 min. For strengthening foam drainage at room temperature, a novel foam fractionation column with a cross-internal component covered superhydrophobic coating was developed. By using the extraction liquor as the feeding solution, a two-stage foam fractionation had been performed. Under the suitable operation conditions, the enrichment ratio and the recovery percentage of ALP were 4.33 and 89.0%, respectively.     

Protein Recovery from Sweet Potato Starch Wastewater by Foam Separation

In this study, an inclined foam separation column was designed to effectively recover protein from sweet potato starch wastewater. The effects of the influent protein concentration, pH, air flow rate, influent volume, foaming time, and inclined column angle on foam separation performance were assessed. The optimum foam separation conditions consisted of influent protein concentration 4.51 mg/mL, pH 4, air flow rate 0.15 mL/min, influent volume 500 mL, foaming time 100 min, and inclined column angle 30°. In these conditions, protein recovery percentage and enrichment ratios were 84.1% and 1.3, respectively. The biochemical oxygen demand (BOD₅) and chemical oxygen demand (COD_Cr) of the residual solution (620 and 950 mg/mL, respectively) were lower than those of the original (influent) solution.     

泡沫分离法回收水溶液中微量钼（Ⅵ）的研究

以十六烷基三甲基氯化铵（CTAC）为表面活性剂,采用自制的泡沫分离塔回收水溶液中的微量钼（Ⅵ）,考察了溶液pH、空气流量、表面活性剂质量浓度等对钼（Ⅵ）回收率和富集率的影响,并对该过程进行动力学分析。实验结果表明：随溶液pH增加,钼（Ⅵ）的富集率和回收率均先增加后减少;随CTAC浓度增加,钼（Ⅵ）的回收率增加而富集率减少;随空气流量增加,钼（Ⅵ）的富集率减少而回收率先增加后减少。在溶液pH为9、气体流量为 200 mL/min、表面活性剂质量浓度为0.30 g/L条件下,钼（Ⅵ）的回收率达到90%,富集倍数达到10倍。动力学分析表明,泡沫分离钼（Ⅵ）的过程是零级动力学过程,拟合方程为ρ=-0.288 8t+4.290 4,R2=0.993 8。     

泡沫分离法分离纯化无患子皂苷的研究

采用泡沫分离法分离纯化无患子皂苷溶液,收集溢出分离柱的泡沫液,采用紫外分光光度计分别测定原液和泡沫液的皂苷含量,通过富集比、回收率以及纯度表征分离效果。结果表明:在进料浓度为 2.0 g/L、进料量为 150 mL、气速为 32 L/h、温度为 30 ℃、pH值为4.3条件下,富集比可达到2.153,收率与纯度分别达到 79.19 % 和 74.68 %。     

基于甘草配伍黄芩同时泡沫分离甘草酸和黄芩苷

为了同时分离甘草中有表面活性的甘草酸和黄芩中无表面活性的黄芩苷,开发了甘草配伍黄芩泡沫分离工艺。通过荧光光谱、紫外吸收光谱和红外吸收光谱分析表明,甘草酸与黄芩苷存在相互作用,并且甘草黄芩配伍强化了甘草酸和黄芩苷的提取。以甘草酸和黄芩苷的富集比和回收率为评价指标,当温度为40℃、气体体积流量为100 ml·min^-1、甘草酸初始浓度为0.2 g·L^-1、甘草黄芩质量比为3：1时,获得甘草酸的富集比和回收率分别为11.0和73.5%,黄芩苷的富集比和回收率分别为5.8和38.5%。通过甘草与黄芩配伍,利用泡沫分离获得黄芩中的黄芩苷。同时,与单独泡沫分离甘草中甘草酸相比,甘草酸的富集比提高了194.9%,回收率提高了23.3%。因此,甘草配伍黄芩能有效泡沫分离甘草酸和黄芩苷。     

Process optimization for foam separation of yak whey protein by response surface methodology

In order to recovery whey protein from yak whey wastewater effectively, a facile method of foam separation to be suitable for the local nomadic herdsmen in Qinghai-Tibet Plateau has been established in this research. The effects of the four factors, protein concentration, gas velocity, temperature and pH, on the performance of foam separation were investigated. Based on the single factor experiments, the response surface software was adopted to optimize and to investigate conditions of foam separation for whey protein, and the optimal conditions were found to be protein concentration of 120 μg/mL, gas velocity of 310 mL/min, temperature of 41°C and pH of 3.8, respectively. The as-obtained results of verification experiments, recovery percentage 88.3% and enrichment ratio 9.25 showed that foam separation technique was a simple equipment and environmental compatibility method to separate whey protein from yak whey wastewater.     

Retention Rate Enhancement of Antioxidant and Cyaniding 3-O-Glucoside Components of the Reconstituted Product from Spray-Dried Black Raspberry Juice by Optimizing Process Parameters

The effects of four operating parameters involved in the spray-drying process, including air inlet temperature (120–150°C), air flow rate (3.5–5.0 m³/h), feed flow rate (2–10 mL/min), and aspirator rate (50–70 m³/h), to produce black raspberry juice powders with the highest retention rate of healthy functional components were optimized using a response surface design. Second-order polynomial models with high R ² (0.955–0.972) values were developed using multiple linear regression analysis. Results showed that the most significant (p < 0.05) process conditions that affected the antioxidant activity and cyanidin-3-O-glucoside content (C3GLU) of powders respectively were the quadratic effects of air inlet temperature and air flow rate and quadratic terms of air and feed flow rates. Laser diffraction particle size analysis and scanning electron microscopy were used to relate the microstructure and quality features. The lowest EC₅₀ (0.0060 mL juice/g 1,1-diphenyl-2-picrylhydrazyl [DPPH]) and the highest C3GLU (4.721 mg/100 mL) values were achieved at an inlet temperature of 120.0°C, air flow rate of 4.20 m³/h, feed flow rate of 8.65 mL/min, and aspirator rate of 55.87 m³/h.     

Removal of Trace Cd2+ Using Continuous Multistage Ion Foam Fractionation: Part II—The Effects of Operational Parameters

A multistage ion foam fractionation column with bubble-cap trays was employed to study the removal of cadmium ions from simulated wastewater having low Cd concentrations (10–30 mg/L), examining the effects of foam height, air flow rate, feed flow rate, and feed Cd concentration. Sodium dodecyl sulfate (SDS) was used to generate foam in this study. An increase in foam height, which reduces liquid hold-up in the generated foam, resulted in the enhancement of the enrichment ratios of both SDS and Cd while the removal and residual factor of Cd showed insignificant change. An increase in air flow rate increased the foam generation rate, foamate volumetric ratio, and the removal efficiency of Cd but decreased the enrichment ratios of both Cd and SDS. The separation factors of both Cd and SDS decreased with increasing feed flow rate, which is mainly attributable to both the effects of the enhancement of foamate volumetric ratio and the increases in both SDS and Cd input rates. An increase in feed Cd concentration was found to increase Cd effluent concentration and SDS removal but to decrease the enrichment ratios of both Cd and SDS because of the increasing liquid entrainment in the produced foam.     

间歇式泡沫分离法回收海水中硼的研究

采用间歇式泡沫分离法研究了海水中硼的回收工艺。主要考察了表面活性剂种类及用量、溶液pH、气体流量等因素对海水中硼的分离性能的影响。实验结果表明：十二烷基三甲基氯化铵（DTAC）、十四烷基三甲基氯化铵（TTAC）、十六烷基三甲基氯化铵（CTAC）以及十八烷基三甲基氯化铵（OTAC） 4种表面活性剂中CTAC对海水中硼的分离效果最好;随溶液pH的增加,硼的回收率和富集比均先增大后减小;随CTAC用量的增加,硼的回收率逐渐增大并趋于稳定,而富集比先增大后减小;随气体流量的增加,硼的回收率先增大后减小,而富集比则逐渐减小。在实验条件范围内,当CTAC质量浓度为0.2 g/L、溶液pH为9、气体流量为200 mL/min时,硼的回收率达到90%,富集比达到8。     

Study on Riboflavin Recovery from Wastewater by a Batch Foam Separation Process

Abstract

A batch recovery of riboflavin via foam separation from industrial simulative wastewater was studied using a cationic surfactant, cetyltrimethyl ammonium bromide (CTAB). The experimental parameters examined were the surfactant concentration, air flow rate, pH, and foam height. Under optimal operating conditions obtained through an orthogonal experiment, the maximum enrichment ratio of 48.7 was achieved for riboflavin along with 99.3% removal efficiency. The optimal operating conditions had the concentration of CTAB at 0.3 g/L, air flow rate at 400 ml/min, foam height at 90 cm, and pH at 12. Therefore foam separation proved to be an effective method to recover the riboflavin in terms of the good enrichment and removal efficiency.     

Optimization of Spray-Drying Process Conditions for the Production of Maximally Viable Microencapsulated L. acidophilus NCIMB 701748

Inrecent years, the use of spray drying for the production of anhydrobiotics has gained the interest of functional food manufacturers, mainly due to cost efficiencies and enhanced product and process flexibility (e.g., enhanced shelf life). In the present work, spray-drying conditions (air inlet temperature and feed flow rate) were optimized for the microencapsulation of the thermo sensitive probiotic lactobacilli strains Lactobacillus acidophilus stabilized in a 60:20:20 (w/w) maltodextrin: whey protein concentrate: D-glucose carrier. A 2³ full-factorial experimental design was constructed with air inlet temperature (120, 140, and 160°C) and feed flow rate (6, 7.5, and 9.0 mL/min) as the independent variables and total viable counts (TVC), water activity (a _w ), and cyclone recovery (CR) defined as the dependent variables. The increase in air inlet temperature from 120 to 160°C induced a significant (p < 0.001) reduction in the TVC from 9.02 to 7.20 log cfu/g, which corresponds to a97.5% loss of the L. acidophilus viable counts. On the other hand, the increase in the feed flow rate from 6 to 7.5 mL/min significantly reduced (p < 0.001) the heat-induced viability loss. A further increase in the feeding rate did not further modify the achieved thermo protection, and a detrimental impact of cyclone recovery (reduction) and water activity (increase) of the powder was observed. Using pruned quadratic mathematical models, the optimum spray-drying conditions for the production of maximally viable microencapsulated L. acidophilus were 133.34°C and 7.14 mL/min. The physicochemical and structural characteristics of the powders produced were acceptable for application with regards to residual water content, particles mean size, and thermo physical properties to ensure appropriate storage stability under room temperature conditions, with a low inactivation rate of L. acidophilus. Microcapsules appeared partially collapsed by scanning electron microscope with a spherical shape with surface concavities.     

Experimental Study on Optimization of the Agglomeration Process for Producing Instant Sugar by Conical Fluidized Bed Agglomerator

This study was conducted to determine the optimal processing conditions for manufacturing instant sugar. The instant sugar was produced with a batch fluid bed agglomerator under the following conditions: inlet air temperature 60–90°C; water flow rate 1–3 mL min^?1; and spraying time 1–10 min. The optimal conditions were estimated using response surface methodology as follows: inlet air temperature of 74.4°C, water flow rate of 2.85 mL min^?1, and spraying time of 10 min. Subsequently, particle density of 1,550 kg m^?3, poured density of 470.13 kg m^?3, tapped density of 599.8 kg m^?3, porosity of 62.1%, mean diameter of 324.66 µm, flowing time of 6.39 s, yield percentage of 78.96%, and desirability of 0.46 were obtained as optimal amounts. The results showed that the quadratic effects of water flow rate and spraying time on flowing time and particle density as well as the effects of spraying time and inlet air temperature on mean diameter and flowing time were significant. Within the temperature range of 60–90°C, the impact of spraying time and water flow rate on instant sugar properties had preference over inlet air temperature. Moreover, the optimal instant sugar required less dissolution time compare to various industrial sugar samples.     

Study on Streptomycin Sulfate Recovery by Batch Foam Separation

The feasibility of foam separation as a technique was assessed for the recovery of streptomycin sulfate from the waste solution by using an anionic surfactant sodium dodecyl sulfate (SDS). The experimental parameters examined were SDS concentration, superficial gas velocity, initial pH, and liquid loading volume. The results showed that sodium dodecyl sulfate as the surfactant for foam separation had good foaming quality and could effectively concentrate streptomycin sulfate of the aqueous solution by technology of foam separation. The enrichment ratio and the recovery rate of streptomycin sulfate were 4.0 and 85%, respectively under the best operating conditions of sodium dodecyl sulfate concentration 0.4 g/L, superficial gas velocity 300 mL/min, liquid loading volume 300 mL and initial pH 6.0 when streptomycin sulfate concentration was 0.5 g/L.     

Protein Removal from Whey Waste by Foam Fractionation in a Batch Process

The work investigates the separation of proteins from whey waste collected from a local confectionery by the foam fractionation technique in batch mode. The purpose of this work was to evaluate performance criteria of protein separation. The effects of pH, the concentration of initial feed solution, the nitrogen flow rate, the % gas hold up, the bubble diameter, the breaking time of foam, and the optimization of the protein–surfactant ratio (1.5:1) were investigated in detail. Maximum enrichment ratio (48.189), %Rp (96.378) were observed at a gas flow rate of 330 ml/min and pH 5 that is closest to isoelectric point of observed proteins (Bovine serum albumin, β-Lactoglobulin, α-lactalbumin).     

Concentration and Drying of Tea Polyphenols Extracted from Green Tea Using Molecular Distillation and Spray Drying

The purpose of this study was to develop a method of combining molecular distillation and spray drying to concentrate and dry tea polyphenols extracts. Molecular distillation and spray drying of tea phenols extracts were performed using an orthogonal array design. The order of importance that influenced molecular distillation was distillation temperature > flux > rotational speed. The optimal conditions for concentration by molecular distillation were 70°C distillation temperature, 10 mL/min flux, and 1,200 n/min rotational speed. Inlet temperature was found to be the most important determinant of spray drying. The order of importance that influenced the spray drying was inlet temperature > feed flux > wind capacity > feed concentration. The optimal conditions for drying of tea polyphenols extracts by spray drying were determined as follows: 170°C distillation temperature, 3 mL/min feed flux, 30% feed concentration, and 30 m³/h wind capacity. Results of this study indicated that the combination of molecular distillation and spray drying was very suitable for the concentration and drying of tea polyphenols extracts. Using this approach to process tea polyphenol extracts can not only maintain the quality of tea polyphenols but also save time and energy.     

Surfactant Recovery by Foam Fractionation using the Gas-Liquid Contactor,Emulsion Venturi

Sodium dodecylbenzene sulfonate (SDBS), an anionic surfactant, was removed from its aqueous solution by foam fractionation in an emulsion venturi, a gas-liquid contactor functioning in self-aspiration. The performance of the reactor was evaluated by measuring the self-aspired gas flow and the mass transfer coefficient in the presence and the absence of SDBS. Data confirmed that both the gas flow self-aspired and the mass transfer coefficient increased with increasing the recirculated liquid flow. However, the presence of SDBS decreased the mass transfer capacity of the reactor influencing self-aspiration capacity in a positive manner. The percentage removal of SDBS in the emulsion venturi increased with increasing the recirculated liquid flow; at the highest liquid flow value used in this work (1.4 m³/h), 96% of SDBS was removed from the solution after 20 min of foam operating. The process was dependant on initial surfactant concentration. Neutral pH and temperature of 25°C were the optimal conditions for the foam separation of SDBS in the emulsion venturi.     

Separation of Bovine Serum Albumin by Foam Fractionation with Sieve Tray Column

A batch foam fractionation column with sieve trays was developed for enhancing the foam drainage. Effects of feeding concentration, air flow rate, number of stages, and sieve pore size on foam fractionation performances were investigated. The results indicated that the sieve trays enhanced the foam drainage effectively and improved enrichment ratio. At the liquid loading volume 490 mL, feeding concentration 0.1 g L^?1, and air flow rate 300 mL min^?1, the enrichment ratio reached 7.56 by using 10 stages of sieve trays with opening ratio of 38.25%, which was 1.84 times of that obtained by the control column.     

茶皂素提取条件的优化及纯化研究

以油茶茶籽粕为原料，采用乙醇水溶液提取茶皂素。在茶籽粉和乙醇料液比1 : 9(g : mL)，乙醇体积分数60%，提取温度60 ℃和提取时间3 h的最佳条件下茶皂素的提取得率达14.9%。用NKA-9型大孔吸附树脂吸附纯化茶皂素粗品，树脂静态吸附与解吸结果表明：树脂静态吸附茶皂素粗提液0.5 h基本饱和，体积分数80%乙醇解吸率为91.1%；动态吸附与解吸时，上样流速8 mL/min较佳，吸附率为66.04%，体积分数80%乙醇洗脱，洗脱流速5.0 mL/min，洗脱体积50 mL时，可使流出液中茶皂素质量浓度在1.25~1.57 g/L之间，茶皂素纯度为95%。     

Spray Drying and Process Optimization of Unclarified Pomegranate (Punica granatum) Juice

In this study, production of pomegranate juice powder using a spray dryer was investigated. To prevent stickiness, maltodextrin dextrose equivalent 6 (DE6) was used as a drying agent. While feed flow rate, feed temperature, and air flow rate were kept constant, air inlet temperature (110–140°C), percentage maltodextrin (MD; maltodextrin dry solids/100 g feed mixture dry solids; 39.08–64.12%), and feed mixture concentration (19.61–44.11 °Brix) were chosen as the independent variables. Product properties investigated included moisture content, hygroscopicity, anthocyanin content, color change, solubility, bulk density, total phenolics content, antioxidant capacity, and sensory properties. The products were produced with high yield (86%) and high antioxidant activity (77%). MD and drying temperature were found to be the most important variables in production of pomegranate juice powders. Because total color change (ΔE), bulk density, antioxidant capacity, and powder yield were affected strongly by the independent variables, these parameters were used in optimization of the process. The optimum temperature, feed mixture concentration, and percentage maltodextrin were 100°C, 30.8 °Brix, and 53.5% MD, respectively. This study revealed that by applying these optimal conditions, pomegranate juice powder with a 55% dry solids yield, 9.78 total color change, 0.35 g/mL bulk density, and 57.8% antioxidant capacity were produced.