Pectinase Production by Aspergillus Niger P-6021 on Citrus Changshan-huyou Peel in Slurry-state Fermentation

The peel of Citrus changshan-huyou, coupled with wheat bran, could be utilized by Aspergillus niger P-6021 in slurry-state fermentation to produce pectinase with suitable enzyme composition for application in apple juice processing. The production of pectinase is improved by additional nitrogen source substances and mineral supplements. The ratio of carbon source substances to nitrogen source substances in the medium also has significant effect on the pectinase production by A. niger P-6021 in slurry-state fermentation. In the optimized medium composition, the maximal enzyme activity could reach 42 U.L^- 1 （polymethylgalacturonase）, 6.7 U.L^- 1 （polymethygalacturatesterase）, and 4.3 U.L^-1 （polymethylgalacturonate lyase）, respectively, after 3 days at 180 r.min^- 1 and 30℃. The crude pectinase shows significant effect to improve the yield and clarification of apple juice. Keywords Aspergillus niger, slurry-state fermentation, pectinase, Citrus changshan-huyou, apple juice

Research on Extraction of Anti-allergic Active Ingredient from Citrus Peels and Its Anti-allergic Activity

[Objective] This study aimed to determine the optimal process conditions for extraction of anti-allergic active ingredient from citrus peels. [Method] Crude anti- allergic active extracts of citrus peels were extracted. Effects of extraction conditions including extraction temperature, ethanol concentration, extraction time and liquid-to-solid ratio on extraction were explored with single-factor experiment, and the extrac- tion process was optimized with orthogonal experiment. [Result] Based on the single- factor experiment and orthogonal experiment, the optimal extraction condition for crude anti-allergic active extracts of citrus peels were determined to be under extraction temperature of 60℃, ethanol concentration of 70%, extraction time of 60 min, liquid-to-solid ratio of 1：25 and twice extraction. [Concluslon] This process condition is of simple operation and high extraction efficiency, which is environment-friendly and suitable for the extraction of crude anti-allergic active extracts from citrus peels. This study provided a new approach and research ideas for the effective and rapid extraction of anti-allergic active ingredient in citrus peels.

Determination of Hesperidin in Citrus Peel by HPLC

[Objective] This study aimed to measure the hesperidin content in citrus peel by high performance liquid chromatography, to provide a scientific basis for quality control and identification. [Method] The hesperidin was extracted with alkaline solution at 70 ~C and pH 6-7, and the purity of hesperidin was determined by HPLC. [Result] The formula for the regression line was Y=466,097Xq3.415 0 （r=0.999 6）, identify- ing the relationship between hesperidin concentration and peak area, and the linear range was 0.2-1.4μg. The hesperidin solution was stable within 24 h at room temperature. The average recovery rate of hesperidin was 98.41%. [Conclusion] The HPLC method is rapid, simple, and with good linear relationship, can be used for routine analysis of hesperidin.

Protective effects of a polymethoxy flavonoids-rich Citrus aurantium peel extract on liver fibrosis induced by bile duct ligation in mice

Objective: To evaluate the possible protective effect of Citrus aurantium peel extract(CAE) against apoptosis in cholestatic liver fibrosis induced by bile duct ligation in mice. Methods: Male ICR mice were divided to 5 groups: 1) Control group(Sham-operated mice), 2) Cholestatic liver injury group induced by bile duct ligation(BDL), 3) BDL mice treated with silymarin(200 mg/kg) for 4 weeks, 4) BDL mice treated with 50 mg/kg CAE for 4 weeks, 5) BDL mice treated with 200 mg/kg CAE for 4 weeks. Mice were sacrificed and liver fibrosis was evaluated by serum and hepatic tissue biochemistry tests and liver histopathological examination. Effects of CAE on inflammation and apoptosis gene regulation were investigated through real-time PCR. CAE effect on lipid metabolism related signaling was determined by western blot analysis. Results: In BDL mice, administration of CAE for 4 weeks markedly attenuated liver fibrosis based on histopathological alteration. Serum and hepatic tissue biochemistry results revealed that CAE(50 and 200 mg/kg) decreased the levels of alanine transaminase, aspartate transaminase, gamma glutamyl transferase, total bilirubin, nitric oxide, and thiobarbituric acid reactive substances. Real-time PCR and western blot analysis showed that CAE regulated inflammation, apoptosis, and lipid metabolism factors increased by BDL. Interleukin family, tumor necrosis factor α, and related apoptosis factors m RNA levels were increased by BDL treatment. However, these increases were suppressed by CAE administration. In addition, CAE effectively increased phosphorylation of AMPactivated protein kinase, nuclear factor E2-related factor 2, and related cytoprotective proteins. Conclusions: CAE can efficiently regulate BDL-induced liver injury with antioxidant, antiinflammatory, and antiapoptotic activities.

Efficacious anti-cancer property of flavonoids from citrus peels

Cancer is one of the two leading human fatal diseases.Drug development for cancer intervention has progressed well in past decades yet existing drugs face many limitations in applications and effectiveness and are often associated with serious of side effects,which can further deteriorate the patients’quality of life.Recent development of natural product based and therapeutically sound anti-cancer agents have gained popularity in the field of functional foods,in which a few have demonstrated efficacy and minimal toxicity toward the prevention and treatment of carcinogenesis.With multiple active molecular components,citrus peels and derived extracts have demonstrated potent efficacious properties against various cancers due in large part to the rich content of flavonoids present in citrus peels.This review summarizes the results of currently available data regarding the in vivo anti-cancer activity of citrus peel flavonoids,and identifies opportunities for subsequent human clinical trials to assess preventive and therapeutic effects in the near future.

Human plasma protein binding of water soluble flavonoids extracted from citrus peels

The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC.The flavonoids were extracted separately by hot and cold water,and higher total flavonoid contents were detected in the former extracts than the latter ones.All the extracts show significant scavenging abilities to both ABTS and DPPH free radicals,which indicates the health benefits of the water extracts of citrus fruits peels.For DPPH radical,the IC50values of hot extract follow as Navel orange(NO)≈Mandarin orange(MO)< Lemon(LE)< Lo tangerine(LO)< Pomelo(PO),while the rank is NO< PO<LE≈MO<LO for ABTS radical.The HPLC results reveal that the kinds and contents of the flavonoids detected in the extracts are different among the species.MO extract has the most neohesperidin dihydrochalcone of 118.76 μmol/L and quercetrin of 211.81 μmol/L of which are much more than the rest extracts.Pomelo extract has the most plentiful flavonoids of naringin with a concentration of 303.28 μmol/L.The high contents of myricetrin and dihydromyricetin which both are potent free radical scavengers may explain the highest free radical scavenging activity of the NO extract.The plasma binding rates decrease with the increasing concentrations of flavonoids,and the flavonoids having plenty hydroxyl groups on both A ring and B ring of the molecular skeleton have relative higher plasma binding rates.In addition,the plasma binding rates of flavonoids with saturated C3-C4 bond decrease significantly with the increasing concentrations.

Preliminary Evaluation for Comparative Antioxidant Activity in the Water and Ethanol Extracts of Dried Citrus Fruit (<i>Citrus unshiu</i>) Peel Using Chemical and Biochemical <i>in Vitro</i>Assays

Comparative antioxidant activities of the water and ethanol extracts obtained from dried citrus fruit (Citrus unshiu) peel were determined using chemical and biochemical in vitro assays. Chemical assays were used for evaluation of 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging, hydrogen peroxide scavenging, and reducing power of both extracts and their total phenolic, flavonoid and tannin contents and antioxidant activities were investigated. Biochemical assays were performed to evaluate the inhibition activities of AAPH-induced rat RBC hemolysis and Fe2+-induced lipid peroxidation using rat brain tissue cells. Linear correlation between the antioxidant activities of both extracts were determined by chemical assays, and total phenolic, flavonoid and tannin contents was observed in concentration-dependent mode. Both extracts showed >95% DPPH radical scavenging and >85% hydrogen peroxide scavenging, and higher reducing capacity at the same level of 3200 ppm. In the inhibition activity of AAPH-induced hemolysis, water extracts showed a strong activity in concentration-dependent mode up to 1600 ppm with no statistical difference found between 1600 and 3200 ppm (P > 0.05). In the inhibition activity of Fe2+-induced lipid peroxidation, ethanol extracts showed the higher inhibition percentage of lipid peroxidation than those of water extracts at the same concentration with no significant difference (P > 0.05) found in the range of 800 to 3200 ppm. The extracts of dried Citrus unshiu peel may be considered as potential antioxidant ingredients of functional food depending on the conditions at which reactive oxygen species are implicated.

Detection of Thrips Defect on Green-Peel Citrus Using Hyperspectral Imaging Technology Combining PCA and B-Spline Lighting Correction Method

In order to find an effective method of detecting thrips defect on green-peel citrus, a defect segmentation method was developed using a single threshold value based on combination of characteristic wavelengths principal component analysis （PCA） and B-spline lighting correction method in this study. At first, four characteristic wavelengths （523, 587, 700 and 768 nm） were obtained using PCA of Vis-NIR （visible and near-infrared） bands and analysis of weighting coefficients; secondarily, PCA was performed using characteristic wavelengths and the second principal component （PC2） was selected to classify images; then, B-spline lighting correction method was proposed to overcome the influence of lighting non-uniform on citrus when thrips defect was segmented; finally, thrips defect on citrus was extracted by global threshold segmentation and morphological image processing. The experimental results show that thrips defect in citrus can be detected with an accuracy of 96.5% by characteristic wavelengths PCA and B-spline lighting correction method. This study shows that thrips defect on green-peel citrus can be effectively identified using hyperspectral imaging technology.

Formulated citrus peel extract gold lotion improves cognitive and functional recovery from traumatic brain injury(TBI)in rats

Traumatic brain injury(TBI)is closely related to neuro-inflammatory response and causes a complex pathological process and serious consequence.In this study,we explored whether the formatted citrus peel extract gold lotion(GL)could have a therapeutic effect on rats suffered TBI.TBI rat model was prepared by the electric Cortical Contusion Impactor(eCCI)device.Prevention against TBI by GL was assessed by the behavioral,organizational of rats and the molecular markers in the brain injury area.The results showed that GL could reduce nerve damage and neurological dysfunction.The mechanisms probably due to that GL could not only reduce the associated damage markers including GFAP,OX-42,TNF-α,COX-2,NF-κB and TLR4 but also promote the expression of VEGF which is responsible for protecting neuronal cells in the injury area.These findings revealed that GL could be a promising preparation for TBI prevention.

Determination of Naringin Content in Peel of Guangxi Citrus maxima (Burm.) Merr by HPLC

[Objectives]To establish a method for determining the naringin content in the peel of Guangxi Citrus maxima(Burm.)Merr.[Methods]The high performance liquid chromatography(HPLC)method was applied.The chromatographic column was Agilent HC-C18(4.6 mm×250 mm,5μm);the mobile phase was acetonitrile-0.1%phosphoric acid(18∶82);the flow rate was 1.0 mL/min;the column temperature was 25℃;the detection wavelength was 283 nm.[Results]Naringin showed a good linear relationship in the range of 0.164-3.27μg,r=0.9999.The average recovery rate was 98.66%,and RSD=1.80%(n=6).[Conclusions]This method is simple,feasible,reproducible,and accurate,so it can be used for the determination of naringin content in the peel of Guangxi C.maxima.

Study on Infrared Spectra of Citrus grandis Peels from Guangxi Zhuang Autonomous Region

[ Objective ] This study aimed to establish the infrared （IR） spectra fingerprints for peels of Citrus grandis from Guangxi Zhuang Autonomous Region. [ Method ] The fingerprint was established by fourier transform infrared spectroscopy （ FT-IR）, and then were analyzed by Omic software. [ Result ] IR spectra fin- gerprint of C. grand/s were successfully established. There were six common peaks in the characteristic spectra of 12 samples. [ Conclusion] The specific, rapid and stable method can be applied to quality control of C. grandis.

Formulation and Optimization of Constituent in Legumes-Based Milk Chocolate Fortified with Citrus Peel Powder

The present study was employed to optimize the process for development of legumes-milk based chocolate using peanut (PN) and yellow-pea (YP) milk using Response surface methodology (RSM). Different combinations of legumes-milk chocolate at various ratios of PN:YP milk with fixed concentration of other regular ingredients were prepared, and the finest combination (1:1) was selected on the basis of their sensory and nutritional properties. PN and YP milk, Jaggery (JG), Butter (BT), and Citrus Peel Powder (CPP) served as independent variables while the dependent variables were allocated to the regression equation to determine folic acid (R2 = 93.15) along with protein content (R2 = 93.11) and vitamin C (R2 = 90.57). The nutritional parameters such as Folic acid, Protein and Vitamin C content were found to be optimum in the milk chocolate. The optimized concentrations of PNM, YPM, JG, BT and CPP were found to be 5.0 ml, 5.5 ml, 18.1 g, 2.9 g and 0.53 g respectively. Addition of JG had an interactive effect on folic acid in YP milk (p < 0.05) and CPP shows a significant. Enhancement of vitamin C was perceived in legume based milk chocolate than the control chocolate due to supplement of CPP.

Chemical Composition of Bergamot （Citrus Bergamia Risso） Essential Oil Obtained by Hydrodistillation

Peel essential oil of bergamot （Citrus bergamia Risso） growing in Tunisia was separated by hydrodistillation and obtained in a yield of 9.7%. The oil composition was investigated using GC and GC-MS with two columns HP-I and HP-Innowax. Fifteen compounds accounting for 98.52% of the oil were identified. The oil was characterized by bigb content oflimonene （59.21%）, linalool （9.51%） and linalyl acetate （16.83%）.

基于生物网络分析研究柑橘属果皮辅助预防2型糖尿病作用

目的:初步阐明柑橘属植物果皮辅助预防2型糖尿病的主成分与机制。方法:体外测定柑橘属植物果皮对α-糖苷酶的抑制活性,后通过网络药理学预测其可能的活性成分及其可能的作用机制,再用分子对接验证。结果:13批柑橘属植物果皮均对α-糖苷酶有一定的抑制作用,且在线性范围内呈现量效关系。网络药理学和分子对接技术预测,得到活性成分柚皮素、桔皮素、月桂酸可能通过氧化应激等途径来抑制高血糖,与炎症中的PI3KAkt、Ras、HIF-1信号通路有关,和血管相关的VEGF信号通路等有关。桔皮素为主成分。结论:柑橘属植物果皮对α-糖苷酶有抑制作用,可能对2型糖尿病有一定的辅助预防的作用。

基于生物网络对柑橘属植物果皮预防高尿酸血症的研究

初步阐明柑橘属植物果皮预防高尿酸血症的药效物质基础与作用机制。通过体外测定柑橘属植物果皮对黄嘌呤氧化酶的抑制作用,评价其预防高尿酸血症的效果,通过网络药理学预测柑橘属植物果皮预防高尿酸血症的物质基础及其潜在作用机制,通过分子对接以验证结果。柑橘属植物果皮对黄嘌呤氧化酶有一定的抑制作用,且在线性范围内呈现量效关系。网络药理学和分子对接技术预测结果显示,柚皮素和桔皮素为主要活性成分,可能通过脂质代谢、血管功能等途径抑制高尿酸血症。芸香科柑橘属植物果皮可应用于大健康产业,用于预防高尿酸血症。

多杆仿形式茶枝柑剥皮取肉装置设计与试验

广东新会一带的茶枝柑是“南药”广陈皮唯一来源,其初加工过程中剥皮取肉环节自动化程度低、并容易产生“汁溅”导致腐蚀广陈皮(俗称“烧皮”),为了实现茶枝柑初加工全程自动化,该研究研发一种新型茶枝柑自动剥皮取肉装置以解决上述问题。首先采用3D扫描与重构技术,获得人手剥皮时果皮真实轨迹和姿态数据,建立人手剥皮位姿数学模型;然后以人手剥皮位姿信息为目标,设计多杆仿形机构并使其轨迹和姿态逼近人手剥皮位姿;最后对设计好的多杆仿形机构进行仿真验证和分析,并加工装配出样机进行实际剥皮试验。试验结果表明,该装置可较好模拟人手剥皮时的位姿曲线,配合真空吸盘吸附,可实现茶枝柑机械式自动剥皮,然后配合包络式柔顺机械爪,实现了茶枝柑无损剥皮取肉,试验结果显示剥皮无损率为80%。该研究结果可为柑橘类水果剥皮初加工提供了理论和试验参考。

不同栽培品种柑橘橘皮黄酮类成分含量及抗氧化活性比较研究

为评价不同栽培品种柑橘橘皮药食两用价值,采用紫外-分光光度法(UV)测定总黄酮及高效液相色谱法(HPLC)测定芸香柚皮苷、橙皮苷、甜橙黄酮、川陈皮素、橘皮素含量,并采用自由基清除试验比较其抗氧化活性,进一步结合多元统计分析的综合质量评价方法进行比较。结果表明大红袍红橘(DHP)总黄酮含量显著高于爱媛38号(AY38)、春见(CJ)、沃柑(WG)及甘平(GP)(P<0.05),与温州蜜柑(CLU)、椪柑(PK)、青见(QJ)及明日见(MRJ)含量及抗氧化能力无差异,说明后四种橘皮提取物可作为天然抗氧化剂。其中CLU及QJ橙皮苷含量显著高于DHP,可作为橙皮苷提取原料。PK与DHP总黄酮、5种黄酮单体含量及抗氧化活性接近,并且聚类热图和优劣解距离法(technique for order preference by similarity to an ideal solution,TOPSIS)分析结果显示,DHP与PK聚为一类,且综合评分排名前两位,可推测PK有作为药用栽培品种的潜力。该研究结果将为橘皮药食两用价值评价提供参考。

HS-SPME-GC-MS与ROAV相结合的4种柑橘果皮精油关键香气物质分析

采用顶空-固相微萃取-气相色谱质谱联用法(HS-SPME-GC-MS)对4种柑橘果皮精油挥发性物质的组成和含量进行分析鉴定,结合相对气味活度值(Relative Odor Activity Value,ROAV)对4种柑橘果皮精油中的关键香气成分进行分析,以期为柑橘果皮精油品质评价与发掘特殊香气柑橘精油提供依据。结果表明,4种柑橘果皮精油共鉴定出62种挥发性成分,包括13种单萜、14种倍半萜、5种烷烃、12种醇类、8种醛类、4种酯类、3种酮类、2种醚类和1种酸类。4种柑橘果皮精油均以单萜化合物相对含量最高(83.00%~91.93%)。按照化合物组成,可将4种柑橘分为2个化学类型:柠檬烯/γ-萜品烯型和柠檬烯/3-蒈烯型。ROAV法从4种柑橘果皮精油中筛选出24种关键香气物质,其中北京柠檬果皮精油中风味贡献最大的物质为紫苏醛,关键香气物质共10种;温州蜜柑、酸橙和枳雀果皮精油中风味贡献最大的物质均为芳樟醇,关键香气物质分别为12种、20种和20种。这些关键香气物质对柑橘果皮精油的香气品质起着重要的作用。

贡柑皮多甲氧基黄酮的提取优化及其油脂抗氧化稳定性研究

目的 优化德庆贡柑皮多甲氧基黄酮的提取,并探究其对油脂抗氧化稳定性的影响。方法 在单因素实验基础上,根据Box-Benhnken的中心组合设计实验,采用响应面法对贡柑皮中多甲氧基黄酮(polymethoxy flavonoids,PMFs)的提取工艺进行优化;采用高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry, HPLC-MS/MS)分析贡柑皮中PMFs组分。结果 提取的最佳工艺参数为:料液比1:3.23 (g:mL)、乙醇浓度87%、超声提取时间46 min,提取率为6.87%;贡柑皮中含有6种PMFs,分别为橘皮素、川陈皮素、5-羟基-2’,4’,7,8-四甲氧基黄酮、黄芩黄酮Ⅱ、栀子黄素B、5-去甲基川陈皮素,相对质量浓度分别为10494.1、8428.4、826.3、678.4、141.3、12.0μg/mL;贡柑皮PMFs提取物对1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)和2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid)ammoniumsalt,ABTS]+自由基具有清除作用,当提取物质量浓度达到2.00 mg/mL时,对DPPH自由基清除率为83.44%,对ABTS+自由基清除率为77.56%;贡柑皮PMFs提取物对油炸油饼中的油脂氧化具有一定的抑制作用,在油炸时间5 h内,添加1.00%贡柑皮PMFs提取物的样品显著降低了油脂的过氧化值和酸价,而添加0.50%贡柑皮PMFs提取物的样品茴香胺值显著降低。结论 优化后的PMFs提取率为6.87%,贡柑皮种含有6种PMFs,对自由基有清除作用且对油脂氧化有抑制作用。

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。