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An Optical Based Biosensor for the Determination of Ammonium in Aqueous Environment

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American Journal of Analytical Chemistry 2012年第5期3卷 364-370页

作者： Nur Ellina Azmi Jaafar Abdullah Musa Ahmad Hamidah Sidek Lee Yook Heng Samsulida Abd Rahman Industrial Biotechnology Research Centre SIRIM Berhad Shah Alam Malaysia Industrial Biotechnology Research Centre SIRIM Berhad Shah Alam Malaysia. School of Chemical Sciences and Food Technology Faculty of Sciences and Technology Universiti Kebangsaan Malaysia Bangi Malaysia. School of Chemical Sciences and Food Technology Faculty of Sciences and Technology Universiti Kebangsaan Malaysia Bangi Malaysia.

A simple and rapid optical biosensor for the determination of ammonium was developed by immobilization of gluta-mate dehydrogenase (GLDH) and diaphorase (Dph) in chitosan film coated on a glass slide employing thiazolyl blue tetrazolium bromide (MTT) as a color indicator. The developed biosensor displays a purple color formation of formazan attributed to the unreacted NADH in the reaction system in the presence of ammonium. The color intensity was found to decrease proportionally with the increase of ammonium concentrations after 10 min exposure. The linearity of the biosensor towards ammonium was in the range of 16.8 – 70 μM (R2 = 0.9955) with detection limit of 11 μM. A good agreement (R2 = 0.9984) with indothymol method was obtained in the measurement of fish pond water samples. The effect of potential interferences such as metals ion has also been evaluated.

关键词： Optical Biosensor Glutamate Dehydrogenase Diaphorase Ammonium

Spectrophotometer with enhanced sensitivity for uric acid detection

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Chinese Optics Letters 2019年第8期17卷 66-70页

作者： Nurfatihah Che Abd Rashid Nor Hafizah Ngajikin Asrul Izam Azmi Rashidah Arsat Suhaila Isaak Noran Azizan Cholan Nur Ellina Azmi Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Johor Bahru Johor Malaysia Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn Malaysia 86400 Bt. Pahat Johor Malaysia Industrial Biotechnology Research Centre SIRIM Berhad 40200 Shah Alam Selangor Malaysia

A spectrophotometer with an LED as the light source for uric acid detection is proposed in this work. The mechanism of uric acid detection is based on energy absorbed by sodium urate, which is a chemical product of uric acid and sodium hydroxide solution. For the performance validation, comparison between the spectrophotometer with an LED and halogen lamp is carried out. Measurement results suggest that the spectrophotometer system with LED light has better sensitivity than that with halogen light. At a 460 nm wavelength,the sensitivity for the spectrophotometer with an LED is 0.0046 dL/mg, which is 73% higher than that with halogen light that records 0.0012 dL/mg. This enhanced sensitivity is attributed to the higher luminous efficacy of the LED light beam. As a result, a larger amount of flux interacts with the sample, leading to the sensitivity enhancement. The spectrophotometer with an LED is also applied for the detection of uric acid in a real human urine sample. Based on the experimental data at a 460 nm wavelength, the method manages to achieve the sensitivity of 0.0016 dL/mg, accuracy of 96.01%, limit of detection of 4.79 mg/dL, and limit of quantification of 14.52 mg/dL. These findings show that the use of LED as the input light source is promising for the spectrophotometer.

关键词： spectrophotometer mechanism show

Effect of Preparation Method on the Physicochemical Properties of MoVNbTe Catalyst for Propane Ammoxidation to Acrylonitrile

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Journal of Chemistry and Chemical Engineering 2010年第6期4卷 29-34页

作者： Ramli Anita Othman Mohd Azizi Jamil Farinaa Fundamental and Applied Sciences Department Universiti Teknologi PETRONAS Tronoh 31750 Malaysia Chemical Engineering Department Universiti Teknologi PETRONAS Bandar Seri Iskandar Tronoh 31750 Malaysia Advanced Materials Research Centre （AMREC） SIRIM Berhad Lot 34 Jalan Hi-Tech 2/3 Kulim Hi-Tech Park Kulim 09000Malaysia

MoVNbTe catalyst has been found to be the most active and selective catalyst in the ammoxidation of propane to ACN, the selective oxidation of propane to acrylic acid and in the oxidative dehydrogenation of ethane to ethylene. However, in our previous work, when 0.5 mL of MoVNbTe catalyst prepared using slurry method was tested in the propane ammoxidation to ACN, it only shows 1% conversion of propane with about 55% selectivity to CAN, thus giving only 0.6% yields to ACN. The poor catalyst activity is attributed to insufficient formation of crystalline phases essential for the propane activation process. In an attempt to improve the physicochemical properties of this catalyst, several preparation methods have been used, namely hydrothermal, reflux, changing the solvent and changing the calcinations temperature. The modified catalysts have been characterized using X-Ray Diffraction （XRD） and N2 physisorption （BET）. The MoVNbTe catalyst prepared by hydrothermal method shows a remarkable improvement in the formation of crystalline phases.

关键词： MoVNbTe catalyst propane ammoxidation acrylonitrile hydrothermal method crystalline phase.

基于微滴数字PCR技术鉴别猪肉掺假方法的建立及评估

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农产品加工 2021年第11期 77-80页

作者：王溪桥解迎双周小平丁功涛马忠仁 Nurul Izza Nordin 兰州海关技术中心甘肃兰州730010 西北民族大学甘肃兰州730124 Industrial Biotechnology Research Centre SIRIM Berhad

探讨微滴数字PCR(Droplet digital PCR,ddPCR)技术在猪肉掺假检测中的应用价值。提取猪肉肌肉组织中的基因组DNA,设计猪源性内标基因引物及探针序列,以ddPCR进行扩增读取结果,在不同物种中进行特异性检测,利用标准质粒DNA检测最低下限... 详细信息

探讨微滴数字PCR(Droplet digital PCR,ddPCR)技术在猪肉掺假检测中的应用价值。提取猪肉肌肉组织中的基因组DNA,设计猪源性内标基因引物及探针序列,以ddPCR进行扩增读取结果,在不同物种中进行特异性检测,利用标准质粒DNA检测最低下限拷贝浓度;在不同掺杂量组织中检测最低比例。结果表明,猪源性ddPCR检测体系特异强,在10~2000 copies/μL的范围内具有较高的检测线性,RSD值小于25%,可检测至猪肉掺杂量为1%的混合样品。基于ddPCR的检测猪肉掺假的方法具有较高的实际应用价值。

关键词：猪肉掺假微滴数字PCR 鉴别检测

青稞麸皮油提取工艺优化及其抑制α-葡萄糖苷酶活性研究

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中国粮油学报 2022年第5期37卷 109-115页

作者：罗龙龙任卫合王丽萍高彩雯杨许花丁功涛 Nurul Izza Nordin 陈士恩西北民族大学生命科学与工程学院兰州730124 西北民族大学生物医学研究中心中国-马来西亚国家联合实验室兰州730124 sirim有限公司工业生物技术研究中心莎阿南40700

以正己烷为溶剂,通过优化提取工艺增加青稞麸皮中油脂的提取率,随后通过扫描电镜探究超声辅助提取对青稞麸皮结构的影响,对青稞麸皮油的体外α-葡萄糖苷酶抑制能力和酶抑制作用类型进行研究。结果表明:在提取工艺为超声时间30 min,超声... 详细信息

以正己烷为溶剂,通过优化提取工艺增加青稞麸皮中油脂的提取率,随后通过扫描电镜探究超声辅助提取对青稞麸皮结构的影响,对青稞麸皮油的体外α-葡萄糖苷酶抑制能力和酶抑制作用类型进行研究。结果表明:在提取工艺为超声时间30 min,超声功率225 W,超声温度30℃,浸提时间12 h,提取率可达到3.62%。通过体外α-葡萄糖苷酶抑制实验表明青稞麸皮油的抑制作用强于市售的阿卡波糖,IC_(50)值为0.736 mg/mL。相较于乙酸乙酯、乙醇作为提取溶剂,正己烷的抑酶效果强于其他溶剂。通过酶动力学实验分析,青稞麸皮油的抑制类型属于混合竞争型抑制。

关键词：青稞麸皮油提取工艺 α-葡萄糖苷酶抑制剂动力学

Bioguided Fractionation and Purification of Natural Bioactives Obtained from<i>Alpinia conchigera</i>Water Extract with Melanin Inhibition Activity

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Journal of Biomaterials and Nanobiotechnology 2013年第3期4卷 265-272页

作者： Zanariah Binti Ujang Thavamanithevi Subramaniam Mazita Md Diah Harmayumi Binti Wahid Badariah Binti Abdullah Ahmad Hazri Bin Abd Rashid David Appleton 3Department of Pharmacology Faculty of Medicine University of Malaya Kuala Lumpur Malaysia Sime Darby Technology Centre Sdn. Bhd. UPM-MTDC Technology Centre III Universiti Putra Malaysia Serdang Malaysia. Industrial Biotechnol- ogy Research Centre SIRIM Bhd. No. 1 Persiaran Dato Menteri Shah Alam Malaysia Natural Product and Cosmetics Program SIRIM Bhd. No. 1 Persiaran Dato Menteri Shah Alam Malaysia

Crude extracts of Alpinia conchigera a species from the Malaysian Ginger (Zingiberaceae) family and its fractions obtained from various extraction methods were assayed for melanogenesis inhibition activity and cell viability. The crude extract obtained from the ethanolic extraction and the super critical fluid extraction did not exhibit significant melanin inhibition activity and was shown to be toxic to the melanocyte cells in comparison to the water extract. The crude aqueous extracts displayed melanin inhibition of 96.38 ± 1.60% and cell viability 109.90 ± 8.32% at a concentration of 500 μg/mL. Bioassay guided fractionation was performed on the water extracts to isolate the active compounds. The actives were identified as trans-cinnamaldehyde and chavicol glucopyranoside with both compound showing potent anti-melanogenesis activity. At 4.9 μg/ml, both trans-cinnamaldehyde and chavicol glucopyranoside gave 85% inhibition of melanin formation in vitro with 77% and 97% cell viability respectively. In comparison, kojic acid, a known skin lightening agent showed 90.0% inhibition at 100 μg/mL. The bioactive composition comprising the extract, active fraction, purified compounds or mixture thereof of Alpinia conchigera may be used for cosmetic and pharmaceutical applications, particularly for the purposes of reducing skin pigmentation.

关键词： Alpinia Conchigera Preparatory HPLC Fractionation Chavicol Glucopyranoside Trans Cinnamaldehyde Anti-Melanogenesis Activity

基于小鼠粪便气味信息的牛乳清蛋白功能效果的鉴别区分

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浙江农业学报 2021年第4期33卷 714-723页

作者：龙鸣张棚刘元林摆小琴张福梅田晓静曹竑周雪雁马忠仁罗丽宋礼 Nurul Izza NORDIN 西北民族大学生命科学与工程学院甘肃兰州730124 西北民族大学生物医学研究中心中国-马来西亚国家联合实验室甘肃兰州730030 甘南州牦牛乳研究院甘肃合作747000 Industrial Biotechnology Research Centre SIRIM BerhadShah AlamSelangor 40700Malaysia

以电子鼻气敏传感器阵列跟踪牛乳清蛋白干预小鼠粪便气味,以期建立基于气味信息无损评价牛乳清蛋白功能的新方法。动物实验结果表明,与NS组比较,给药牛乳清蛋白试验组血清中的超氧化物歧化酶(SOD)活性上升,丙二醛(MDA)含量显著下降,牛... 详细信息

以电子鼻气敏传感器阵列跟踪牛乳清蛋白干预小鼠粪便气味,以期建立基于气味信息无损评价牛乳清蛋白功能的新方法。动物实验结果表明,与NS组比较,给药牛乳清蛋白试验组血清中的超氧化物歧化酶(SOD)活性上升,丙二醛(MDA)含量显著下降,牛乳清蛋白在小鼠血清中具有抗氧化的能力。电子鼻实验单因素方差分析发现,样品量、顶空生成时间、顶空生成体积和载气流速对传感器S5影响均不显著,对其他传感器响应信号的影响显著。结合典则判别分析获得电子鼻检测较佳条件为:样品量1粒,顶空生成时间10 min,顶空生成体积150 mL,载气流速200 mL·min-1。结合主成分分析和典则判别分析,电子鼻基本可将牛乳清蛋白不同灌胃剂量与对照组小鼠粪便样品区分,并区分不同灌胃剂量的不同周期组小鼠粪便样品。采用多元线性回归分析建立了小鼠体重的预测(R 2=0.1227),效果尚可。典型相关分析结果表明,粪便电子鼻气味信息与其生理指标两者有着极好的相关性,关联性较强。基于干预小鼠粪便气味信息,可以实现牛乳清蛋白干预与对照药物处理的区分,为食品体内功能性无创评价提供了方法思路。

关键词：电子鼻牛乳清蛋白气味信息衰老小鼠无创评价

Apoptosis,antimicrobial and antioxidant activities of phytochemicals from Garcinia malaccensis Hk.f

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Asian Pacific Journal of Tropical Medicine 2012年第2期5卷 136-141页

作者： Muhammad Taher Deny Susanti Mohamad Fazlin Rezali Farah Syahidah Ahmad Zohri Solachuddin Jauhari Arief Ichwan Suhaib Ibrahim Alkhamaiseh Farediah Ahmad Department of Pharmaceutical Technology Kulliyyah of PharmacyInternational Islamic University MalaysiaJalan IstanaBandar Indera Mahkota25200 KuantanPahangMalaysia Department of Biomedical Science Kulliyyah of ScienceInternational Islamic University MalaysiaJalan IstanaBandar Indera Mahkota25200 KuantanPahangMalaysia sirim Rerhad(National Metrology Laboratory) Lot PT 4803Bandar Baru Salak Tinggi43900 SepangSelangorMalaysia Kulliyyah of Dentistry International Islamic University MalaysiaJalan IstanaBandar Indera Mahkota25200 KuantanPahangMalaysia Department of Chemistry Faculty of ScienceUniversity Teknologi Malaysia81310 UTMJohorMalaysia

Objective:To study the chemical constituents of stembark of Garcinia malaccenm（***） together with *** and antioxidant ***:Purification and structure elucidation were carried out by chromatographic and spectroscopic techniques, *** and trypan blue exclusion methods were performed to study the cytotoxic *** activity was conducted by dise diffusion and microdilulion methods, whereas antioxidant activities were done by ferric thiocyanate method and DPPH radical ***:The phylochemical study led lo the isolation ofα,β-mangostin and cycloarl-24-en-3β-ol.α-Mangostin exhibited cytotoxic activity against HSC-3 cells with an IC50 of 0.33μM.β- andα-mangostin showed activity against K562 cells with IC50 of 0.40μM and 0.48μM,respectively,α-Mangostin was active against Gram-positive bacteria, Staphylococcus aureus（***） and Bacilus anthracis（***） with inhibition zone and MIC value of（19 mm;0.02S mg/mL） and（20 mm;0.013 mg/mL）,*** antioxidant assay,α-mangostin exhibited activity as an inhibitor of lipid ***:*** presenceα- andβ-mangostin and cycloart-24-en-3β-ol.β-Mangostin was found very active against ***-3 cells and *** results suggest that mangoslins derivatives have the potential to inhibit the growth of cancer cells by inducing *** addition,α-andβ-mangostin was found inhibit the growth of Cram-positive pathogenic bacteria and also showed the activity as an inhibitor of lipid peroxidation.

关键词： Garcinia malaccensis Guttiferae Apoptosis Antibacterial Antioxidant

枸杞总黄酮提取工艺优化及不同年份枸杞总黄酮含量测定

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西北民族大学学报（自然科学版） 2019年第3期40卷 70-75页

作者：刘元林龙鸣田晓静张福梅陈士恩马忠仁 NuruI Izza Nordin 西北民族大学生命科学与工程学院甘肃兰州730124 西北民族大学生物医学研究中心中国-马来西亚国家联合实验室甘肃兰州730030 Industrial Biotechnology Research Centre SIRIM Berhad1 Persiaran Dato' MenteriSection2 40700 Shah AlamSelangorMalaysia

为探究枸杞贮藏过程中总黄酮含量变化规律,以枸杞总黄酮提取率为指标,采用单因素实验研究浸提温度、乙醇体积分数、料液比和提取时间4因素对枸杞总黄酮提取率的影响,设计正交试验优化提取工艺,并在优化条件下研究不同年份枸杞总黄酮含... 详细信息

为探究枸杞贮藏过程中总黄酮含量变化规律,以枸杞总黄酮提取率为指标,采用单因素实验研究浸提温度、乙醇体积分数、料液比和提取时间4因素对枸杞总黄酮提取率的影响,设计正交试验优化提取工艺,并在优化条件下研究不同年份枸杞总黄酮含量及理化指标间的差异.结果发现,最佳提取工艺参数即浸提温度70℃、乙醇体积分数80%、料液比1∶15g/mL、提取时间2.5h、提取次数为2次.在此条件下,发现枸杞总黄酮含量随贮藏时间延长而呈现下降的变化趋势,这为枸杞总黄酮的开发利用和快速鉴别枸杞新陈提供理论依据.

关键词：枸杞黄酮工艺优化生产年份