Study on Extraction of Pectin from Orange Peels

The comparison was conducted to investigate the higher extraction rate between two methods including alcohol deposition with acid hydrolysis and micro- wave-assistant extraction technique. The experimental results showed that the former method led to a better extraction effect. For the method of alcohol deposition with acid hydrolysis, the technique parameters were optimized through I.s （34 ） orthogonal e^periment based on the results of single factor experiments, after investi- gated the effect of solid to liquid ratio, pH, extraction temperature and extraction time on the pectin extraction rate. tersrm technique was employed to extract pectin. The selected parameter was obtained by means On the basis of the optimal technical parmne- of L16 （45） orthogonal experiment after studied the effect of solid to liquid ratio, extraction temperature, microwave treatment period, pH and microwave power on pectin extraction yield. Repetitive examinations of two methods were carried out separately, pectin extraction rate with the fLrst technique was 14.57% and that with the second method was 11.62%. The charac- teristics of the pectin sample prepared by alcohol deposition with acid hydrolysis were further investigated. The research demonstrated that mass percent of pectin was 87.23%. The esterification degree of pectin was 75.66% ,and pectin sample color was from creamy white to pale yellow.

Optimization of Extraction and Characterization of Pectin from Grapefruit Peels

In this study, pectin was extracted from grapefruit peels with hydrochloric acid and precipitated with 95% ethanol solution and 5% tartaric acid. The physical and chemical properties of pectin obtained were analyzed, including color, texture, degree of esterification, and water solubility. The effects of peel to sol- vent ratio, pH of the solvent, extraction temperature and extraction duration on pectin extraction rate were investigated. On the basis of single-factor experiments, an L9 （34） orthogonal experiment was performed to screen the optimal extraction conditions. According to the results, the optimal combination of technical parame- ters was A1B3 C1 D3, i. e. , solid to liquid ratio 1：40 （g： ml）, pH 2.0, extraction duration 70 rain, extraction temperature 90 ℃. The average pectin extraction rate was 68.60% ; the color of pectin extracted under the optimal conditions varied from milky white to light yellow; the degree of esterification of pectin extracts was 65. 71% ; the extracted pectin exhibited good water solubility. Key words Pomelo peel; Pectin extraction; Optimum conditions; Esterification degree; Water solubility

Pectinmethylesterase extraction from orange solid wastes: Optimization and comparison between conventional and ultrasound-assisted treatments

During orange juice production, a half of fresh oranges weight is considered as production waste (peels, pulp, seeds, orange leaves and damaged orange fruits). An alternative for the management of these wastes is their treatment by addition of lime and a latter pressing, obtaining a press cake and a press liquor rich in sugars (10°Brix) and citric acid, protein, pectin and ethanol. For non-thermal concentration of press liquor to obtain citruss molasses (65°-70°Brix), the removal of pectin is necessary. Traditionally, depectinization of juices has been done by using pectinmethylesterase (PME) enzymes from external sources. In this work it performed the extraction of PME enzymes from orange peels to obtain the optimum extraction conditions. Two different methods of solventextraction were compared (conventional andultrasound-assisted methods). For the conventional extraction experiments, a central composite design with three variables ([NaCl], pH and time) and five replicates of the center point was used. For ultrasound-assisted extraction, experiments were done at pH = 5.5 and [NaCl] = 1.25M), varying extraction time (1-30 min). Response variables were PME activity, protein content and a ratio between them, named PME effectiveness (ηPME). At the same experimental conditions (pH =5.5, [NaCl] = 1.25 M, t = 15 min) it was found that conventional extractions led to slightly better results in terms of ηPME than ultrasound-assisted extraction method.

Viscous-flow properties and viscosity-average molecular mass of orange peel pectin

The viscous-flow properties of pectin from the residue of orange peel after extraction of essential oil and flavonoid were studied and the viscosity-average molecular mass(Mv,ave) of this kind of pectin was determined.Experimental results show that Arrhenius viscous-flow equation can be applied to describing the effect of temperature on viscosity of this kind of orange peel pectin solutions with the average viscous-flow activation energy being 17.91 kJ/mol(depending on the concentration).Neither power equation,η =K1 cA1,nor exponential equation,η=K2exp(A2c) can describe the effect of concentration on viscosity of this kind of orange peel pectin solutions well.However,it seems that exponential equation model is more suitable to describe their relation due to its higher linear correlation coefficient.Schulz-Blaschke equation can be used to calculate the intrinsic viscosity of this kind of orange peel pectin.The Mv,ave of the orange peel pectin is 1.65×105 g/mol.

Technological Conditions of Salting Out Method for Extracting Shaddock Peel Pectin

[Objective] The precipitation conditions of salting out method for extracting shaddock peel pectin were studied.[Method] Taking shaddock peel as the raw material, the optimal technological conditions for pectin precipitation were obtained by precipitating shaddock peel under dif-ferent salting-out conditions.[Result] The optimal conditions of salting out method for precipitating shaddock peel pectin were as follows: aluminum sulfate saturated solution: pectin extract 1∶1, salting out time 60 min, salting out temperature 60℃, salting out pH 4, and the extraction rate reached 6.8%.[Conclusion] Precipitation of pectin through salting out method reduced the consumption of ethanol, energy consumption and production cost.

Fast Determination of Essential Oil from Dried Menthol Mint and Orange Peel by Solvent Free Microwave Extraction Using Carbonyl Iron Powder as the Microwave Absorption Medium

An improved solvent free microwave extraction, in which a kind of microwave absorption medium （carbonyl iron powder） was used, was applied to the extraction of essential oil from dried menthol mint and orange peel without addition of any solvent and pretreatment. It took much less time of extraction （30 min） than microwave-assisted hydrodistillation （90 min） and conventional hydrodistillation （180 min）. The kinds of chemical compositions in essential oil extracted by different methods were almost the same and such improved solvent free microwave extraction can be a feasible way in extraction of essential oil from dried plant materials.

Orange Peel Extract Mediated Silver Nanofluid as Corrosion Inhibitor for X80 Steel in Simulated Oilfield Scale Dissolver

Silver nanofluid was prepared by bio-reduction reaction between orange peels extracts(OPE)and silver nitrate and characterized by spectroscopic and microscopic techniques.Colloidal nanoparticles of sizes between 40-50 nm and spherical shape were obtained.The nanofluid was applied as anticorrosion additive to inhibit corrosion of X80 steel in simulated oilfield scale dissolver solution(1.0 M HCl)at various temperatures.The nanofluid(OPE-AgNPs)was 98.9% and 84.3% efficient at 30℃ and 60 ℃ respectively as determined by weight loss measurement.In comparison with OPE,OPE-AgNPs shows better corrosion inhibition and higher resistance to thermal degradation.Some kinetic and thermodynamic models were used to characterize the inhibition process.OPE-AgNPs could be optimized and used as alternative anticorrosion additive for scale dissolution liquor in the industry.

Ultrasound-assisted extraction of pectin from Citrus limetta peels:Optimization,characterization,and its comparison with commercial pectin

With an aim of complete reuse and recycling of citrus by-products,this study investigated the pectin extraction from Citrus limetta peels employing the ultrasound-assisted extraction(UAE)technique.The extraction process was optimized using Box-Behnken Design and a maximum pectin yield of 28.82%was obtained under the optimal conditions of 40℃ temperature,37%amplitude,and 1.9 pH after 24 min sonication time,which was validated by the experimental results(28.73±0.12%).The pectin extracted under optimum conditions was characterized for its physicochemical,antioxidant,functional,structural,thermal,apparent viscosity and was compared with commercial pectin.Both commercial(CP)and ultrasound extracted pectin(UAEP)were highly esterified with degree of esterification of 59.71±0.12%and 55.29±0.51%,respectively and methoxyl content of 7.06±0.10%and 7.19±0.15%,respectively.In addition,UAEP exhibited high antioxidant and similar water/oil holding capacities and emulsifying properties as compared to CP.XRD patterns of pectin samples suggested high crystallinity of UAEP than CP,SEM exhibited smoother surface of UAEP as compared to CP,and FT-IR spectra proved the presence of GalA units in both samples.The thermal analysis by DSC and TGA showed high thermal stability of UAEP than CP.A detailed comparative study on properties of ultrasound extracted pectin from C.limetta peels and commercial pectin confirmed that the extracted pectin was of good quality as can be potentially utilized as food ingredient in food sector.

Green Synthesis of Silver Nanoparticles Using Aqueous Orange and Lemon Peel Extract and Evaluation of Their Antimicrobial Properties

Green synthesis of silver nanoparticles (AgNPs) using aqueous extracts of orange and lemon peels, as a reducing agent, and silver nitrate salts as a source of silver ions is a promising field of research due to the versatility of biomedical applications of metal nanoparticles. In this paper, AgNPs were synthetized at different reaction parameters such as the type and concentration of the extracts, metal salt concentration, temperature, speed stirring, and pH. The antibacterial properties of the obtained silver nanoparticles against E. coli, as well as the physical and chemical characteristics of the synthesized silver nanoparticles, were investigated. UV-Vis spectroscopy was used to confirm the formation of AgNPs. In addition to green biogenic synthesis, chemical synthesis of silver nanoparticles was also carried out. The optimal temperature for extraction was 65˚C, while for the synthesis of AgNPs was 35˚C. The synthesis is carried out in an acidic environment (pH = 4.7 orange and pH = 3.8 lemon), neutral (pH = 7) and alkaline (pH = 10), then for different concentrations of silver nitrate solution (0.5 mM - 1 mM), optimal time duration of the reaction was 60 min and optimal stirring speed rotation was 250 rpm on the magnetic stirrer. The physical properties of the synthesized silver nanoparticles (conductivity, density and refractive index) were also studied, and the passage of laser light through the obtained solution and distilled water was compared. Positive inhibitory effect on the growth of new Escherichia coli colonies have shown AgNPs synthesized at a basic pH value and at a 0.1 mM AgNO3 using orange or lemon peel extract, while for a 0.5 mM AgNO3 using lemon peel extract.

Removal of methyl orange from aqueous solution by Azolla filicoloides:Synthesis of Fe_3O_4 nano-particles and its surface modification by the extracted pectin of Azolla

The modified Fe3O4 nanoparticles with the extracted pectin from the cell wall of Azolla filicoloides（FNEP） can remove methyl orange as a watersoluble azo dye from waste water better than Azolla and the extracted pectin from Azolla（EPA）,alone.It could be due to more crowding the main functional groups of uptake after binding pectin with nanoparticles.Thermodynamic studies showed that adsorption equilibrium constant（KL） and maximum adsorption capacities（Q（max）） were increased with decreasing temperature（exothermic）.The maximum uptake capacity（Q（max）） of dye by FNEP in a batch reactor was 0.533,0.498 and 0.446 mmol/g at 5,25 and 50℃,respectively.The enthalpy change（△H） and entropy change（△S） were 15.31 kJ/mol and 0.02434 kJ/mol K,respectively.

Eco-Friendly Production of Silver Nanoparticles from Peel of Tangerine for Degradation of Dye

Green chemistry methods for production of nanoparticles have many advantages, such as ease of use, which makes the methods desirable and economically viable. The aim of the present work was to green synthesise silver nanoparticles (SNPs) using aqueous tangerine peel extract in different ratios (2:1, 1:1, 1:2). The formed SNPs were characterised using ultraviolet-visible (UV-Vis) spectrophotometry, and transmission electron microscopy (TEM). The UV-Vis spectra showed that the highest absorbance was observed when the ratio of peel tangerine extract to silver nitrate solution was 1:2. The transmission electron micrographs showed the formation of poly dispersed nanoparticles. It was found that the average diameter of the nanoparticles was 30.29 ± 5.1 nm, 16.68 ± 5.7 nm, and 25.85 ± 8.4 nm, using a tangerine peel solution and silver nitrate solution ratio of 2:1, 1:1, and 1:2, respectively. The formed SNPs were evaluated as catalysts for methyl orange dye degradation, and the results confirmed that SNPs can speed up the degradation of the dye.

协同微波法提取香蕉皮果胶的工艺研究

以本地香蕉皮为原料,采用不同提取剂协同微波法提取果胶,分析果胶的产率及理化性质,结果显示六偏磷酸钠协同微波法来制备皮果胶得率和品质较好。以六偏磷酸钠提取剂协同微波提取香蕉皮果胶,通过单因素试验和正交法优选,确定了香蕉皮果胶提取的最优工艺条件。结果表明:加入0.6%含量的六偏磷酸钠螯合剂辅助微波法提取果胶的最佳工艺参数为:料液比为1∶12 g/mL、pH值为2、微波功率为800 W、微波时间为3 min,果胶提取率达10.15%。

柑桔皮果胶提取工艺研究进展及果胶应用现状

柑桔类水果是世界上种植面积最大、产量最高的水果,柑桔皮等不可食用部分每年产生量大。柑桔皮中含有果胶、类黄酮、类胡萝卜素、香精油等多种功能性成分,直接废弃会造成资源浪费和环境污染问题。利用柑桔皮提取果胶是柑桔废弃物资源化利用的有效途径之一。为了促进柑桔皮资源绿色环保和高效开发利用,对国内外柑桔皮果胶提取研究现状及果胶应用现状进行了梳理分析。

橙皮中柠檬烯提取工艺的研究进展

柠檬烯是橙皮中重要的化学成分,具有杀菌、抗氧化、抗病毒和降低胆固醇等生理活性作用,被广泛用于制药、食品和香料等领域。对溶剂萃取法、水蒸气蒸馏提取法、索氏提取法和超临界萃取法四种提取柠檬烯的方法进行介绍,引入其相关的检测方法和技术标准,旨为柠檬烯的应用生产提供参考价值。

基于联产工艺的橙皮精油气相色谱-质谱指纹图谱的构建及成分分析

目的构建果胶精油联产工艺获得的橙皮精油的指纹图谱,并进行成分分析。方法通过气相色谱-质谱法采集20批次橙皮精油样品的总离子流图(total ions current,TIC),运用“中药色谱指纹图谱相似度评价系统(2012版)”寻找共有峰并建立对照指纹图谱,采用美国国家标准与技术研究院(National Institute of Standards and Technology,NIST)谱库检索结合保留指数技术对共有峰进行成分鉴定,运用SPSS 29.0软件对共有峰进行主成分分析。结果指纹图谱的精密度、重复性和稳定性等方法学考察符合要求,所有样品TIC图相似度均大于0.998,提炼出9个共有峰,经过质谱鉴定,在共有峰中,D-柠檬烯相对含量最高,占82.77%,其次为月桂烯、烩烯、右旋α-蒎烯等,依次占比8.79%、3.62%、3.27%;经主成分分析,前两个主成分因子的累积方差贡献率为67.4%,微量成分烩烯和3-蒈烯对主成分因子的贡献最大。结论对由果胶精油联产工艺获得的橙皮精油建立了气相色谱-质谱指纹图谱,探明其共性化合物成分及影响力,为其质量控制提供了科学依据。

不同提取方法对核桃青皮果胶结构性质及功能活性的影响

以核桃青皮为原料,采用传统水浴酸提法、超声辅助酶提法和草酸铵提法提取果胶,分析3种工艺所得果胶的结构及功能差异。结果表明:传统水浴酸提法所得果胶得率最高,达到(62.84±1.31)mg/g,为高酯果胶,乳化活性及乳化稳定性较差,凝胶内聚性较好但保水性较差,抗氧化活性一般;超声辅助酶提法所得果胶为低酯果胶,乳化活性及乳化稳定性最佳,胶凝性一般,对DPPH自由基的清除率较高;草酸铵提法所得果胶为低酯果胶,乳化活性较好,胶凝性最佳,对DPPH自由基的清除率较高。

生物酶辅助提取橘皮色素及其对羊绒染色的性能

为扩宽天然染料色谱并利用废弃物染色,通过生物酶辅助醇水提取橘皮中的天然色素,并将该色素应用于羊绒染色,分析该色素对羊绒染色的性能。首先分别用纤维素酶、果胶酶以及两种酶的组合对橘皮进行提取,通过单因素试验,探讨生物酶用量、乙醇浓度、提取温度、提取时间对提取效果的影响;然后采用橘皮色素对羊绒进行直接染色发现日晒牢度为2级,进一步研究提高日晒牢度的方法,实验结果表明用金属媒染剂、单宁-金属复合媒染剂、固色剂M对染色后羊绒进行后处理,以提高橘皮色素染色羊绒的耐日晒色牢度、耐皂洗色牢度。结果表明:橘皮色素最佳提取工艺为生物酶用量1%(o.w.f),其中纤维素酶和果胶酶质量比为2∶1,乙醇质量分数50%,提取温度80℃,提取时间100 min,料液比1∶20。橘皮色素对羊绒染色具有较高的K/S值,耐皂洗色牢度和耐日晒色牢度可达3级以上。从废弃物中提取天然染料色素,有着较高的应用价值和附加价值,为废弃资源再利用提供了一条有效途径。

桔皮中果胶提取技术的试验分析

酸浸提法提取果胶具有快速、简便、易于控制、提取率较高等特点 ,用盐酸浸提、乙醇沉淀法进行了从桔皮中提取果胶的工艺试验。研究结果表明 ,提取的液料质量比为 10～ 15、浸提液为 p H2～ 3、浸提时间为 4 5～6 0 m in、浸提温度为 80℃左右时 ,果胶提取效果较好。在单因素试验的基础上用正交试验进行工艺参数的优化 ,其适合的工艺条件是 :液料质量比为 10、浸提液 p H值为 2、浸提温度为 80℃、浸提时间为 4 5 min,在此工艺条件下进行试验 ,其果胶提取率达 70 .6 8%。

微波辅助提取橘皮果胶的优化条件研究

以橘皮为原料,用微波辅助法提取果胶,通过正交试验,得到优化工艺:以盐酸作为萃取剂,pH值为1.5,液料比为10:1(ml/g),微波加热时间为6min,微波处理方式为27%×800W。

柑橘皮果胶的改进提取工艺研究

以新鲜柑橘皮为原料,采用高速匀浆提取和对残渣进行酸水解再次提取的两步法提取工艺制备匀浆果胶和酸水解果胶产品。通过单因素试验和正交试验确定了匀浆提取和酸水解提取的最佳工艺参数并对果胶的脱色和分离方法进行了相关研究。实验结果表明,采用改进工艺提取后柑橘果胶产品总得率比普通一次性酸水解制备工艺明显提高;采用活性炭和聚酰胺为脱色剂进行果胶脱色可以有效提高脱色效果。