Development of acoustic nonwoven materials from kapok and milkweed fibres

Acoustic properties of textile materials have been studied for several decades. But, mostly used materials were synthetic, and hence, they were not eco-friendly in nature. Therefore, an attempt was put forward to try the sound absorption property of natural fibres and their blends by needle-punched nonwoven techniques. Nonwoven fabrics of ideal materials are used as acoustical insulation products because they have high total surface area. The effect of blend proportion of kapok and milkweed fibres with cotton, fabric GSM, bulk density and distance of fabric from sound source on sound reduction of nonwoven fabrics was investigated. The sound reduction increases with increase in blend proportion of kapok and milkweed fibres. A nonwoven fabric of cotton/milkweed 40/60 shows the highest sound reduction potential. As the distance between the fabric and sound sources increases, the sound reduction also increases linearly due to reduction of sound intensity which reduces the transmission of sound through the fabric. There is a positive correlation between fabric GSM and sound reduction and negative correlation between bulk density and sound reduction. Further, the thermal conductivity of nonwoven samples decreases with increase in kapok and milkweed blend proportion due to increase in thickness of samples. Hence, the kapok- and milkweed-blended nonwoven samples provide sound as well as thermal insulation characteristics.     

Studies on the antioxygenic activity of bitter gourd (Momordica charantia) and its fractions using various in vitro models

BACKGROUND: A study was undertaken to evaluate the antioxygenic activity of bitter gourd pulp and seed powders as well as their various solvent extracts using different methods and to minimise the oxidative deterioration of lipids by natural antioxidants. RESULTS: Bitter gourd pulp and seed powders at 20 g kg^?1 and their ethanol/water extracts exhibited stronger antioxygenic activity than other solvent extracts. Bitter gourd pulp and its extracts showed slightly higher antioxygenic activity than bitter gourd seed and its extracts. This may be attributed to the presence of higher amounts of phenolics and flavonoids, which have been reported as potential antioxidants. The seed portion of bitter gourd contained higher levels of total protein (188.3 g kg^?1), total fat (238.9 g kg^?1) and crude fibre (350.2 g kg^?1) than the pulp portion. Fatty acid analysis of bitter gourd seed oil indicated the presence of α‐eleostearic acid, an isomer of conjugated linolenic acid, as a major fatty acid, but this acid was absent in the pulp. CONCLUSION: The results of this study confirmed the presence of antioxygenic compounds in both bitter gourd pulp and seed. In particular, their ethanol/water extracts showed great potential as natural antioxidants to inhibit lipid peroxidation in foods. Copyright © 2010 Society of Chemical Industry     

Chemical pretreatments and partial dehydration of ash gourd (Benincasa hispida) pieces for preservation of its quality attributes

Ash gourd (Benincasa hispida) is a commonly consumed vegetable in Asian subcontinent. Cut ash gourd pieces undergo severe decay within two days probably due to physical, biochemical and microbiological activities. Ash gourd pieces were chemically pretreated with sodium salt of ethylene diamine tetra acetic acid (sodium EDTA), calcium chloride (CaCl₂), citric acid and potassium metabisulphite (KMS) and dehydrated up to 30 percent moisture with an aim to extend its shelf life. Storage study of these samples was done with respect to texture, colour, bacterial content and water holding capacity. Shelf life was extended from two days to one month. Pretreatment using a combination of 1 mM EDTA, 2.5 percent KMS, 0.5 percent citric acid and 2.5 percent CaCl₂ and partial dehydration to 30 percent moisture found to be a good method in preservation of cut ash gourd pieces.     

Bitter gourd (Momordica charantia) modulates activities of intestinal and renal disaccharidases in streptozotocin-induced diabetic rats

During diabetes, structural and functional changes in the alimentary tract are known to take place resulting in increased absorption of intestinal glucose and alterations in the activities of brush border disaccharidases. Similar observations are also reported in the renal cortex. In the present investigation, we examined the effect of feeding bitter gourd fruit devoid of seeds on activities of intestinal and renal disaccharidases, viz., maltase, sucrase, and lactase in streptozotocin-induced diabetic rats. Normal and diabetic rats were fed either with basal diet or a diet containing 10% bitter gourd powder. Specific activities of intestinal disaccharidases were significantly increased during diabetes, and supplementing bitter gourd in the diet clearly indicated amelioration in the activities of maltase and lactase during diabetes. However, a significant change was not observed with sucrase activity by feeding of bitter gourd. During diabetes, renal disaccharidase activities were significantly lower than those in the control rats. Bitter gourd supplementation was beneficial in alleviating the reduction in maltase activity during diabetes. However, not much change in the activities of sucrase and lactase was observed upon feeding. This positive influence of feeding bitter gourd on intestinal and renal disaccharidases clearly indicates their beneficial role in the management of diabetes, thus making diabetic animals more tolerant to hyperglycemia.     

Acoustic performance of woven fabrics in relation to structural parameters and air permeability

This work deals with the study of the acoustic characteristics of woven fabrics in relation to fabric structural parameters and air permeability. In order to achieve the objectives of the research, sound absorption coefficient of woven fabric samples was determined via impedance tube method. Samples with various pick densities and yarn twist were used. The effect of fabric thickness was analyzed using three and six layered test samples. Results showed that, while for all samples the minimum values of sound absorption were observed at frequency bands of 250 and 2000?Hz, the maximum sound absorption occurred at the frequency of 1000?Hz. Results also indicated that fabrics woven at pick density of 30?thread/cm exhibited higher sound absorption than fabrics woven at other pick densities. It was found that, noise reduction coefficient of three and six layered samples, woven at low pick densities showed significant increases in comparison to those woven at high pick densities. It was also established that samples woven with lower weft yarn twist absorb sound wave more efficiently. It was concluded that fabric air permeability can be used as a criterion of sound absorption behavior of woven fabrics.     

Partial properties of an aspartic protease in bitter gourd (Momordica charantia L.) fruit and its activation by heating

Bitter gourd (BG fruit) is usually heated in hot water to reduce bitterness and improve flavour before being served. Protein extract from BG was analyzed for protease activity by gelatin-gel electrophoresis. The study showed that the proteolytic activity in BG flesh was enhanced by heat-treatment at temperatures ranging from 50 °C to 75 °C. An aspartic protease (AP) was characterized by gel electrophoresis. The optimal AP activity was at pH 7; the pI of the AP was demonstrated to be 4.8; the protein molecular weight of the BG–AP was estimated to be 60 KD by SDS–PAGE. The AP was implicated in the proteolysis of the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase.     

4-磺酸苯基卟啉与铅显色反应测定食品中的痕量铅

采取分光光度法研究了铅与TPPS4的显色反应条件,结果表明,用盐酸羟胺作辅助络合剂,以邻二氮菲、硫氰酸铵、酒石酸钾钠作联合掩蔽剂,在室温及碱性介质(pH12)条件下,TPPS4与铅只需12min即可完全生成淡紫色络合物,该络合物的最大吸收波长为465nm,络合比为1:1,当铅含量在0μg/mL～0.2μg/mL时,萃取曲线呈线性关系。通过APDC/MIBK体系萃取分离并富集样品中的铅离子,将TPPS4络合显色方法用于部分食品中痕量铅的测定,结果令人满意。     

Stability of betacyanin from red pitahaya (Hylocereus polyrhizus) and its potential application as a natural colourant in milk

The effects of temperature (30, 50, 85 and 100 °C) treatment and 10 weeks of refrigerated storage (4 °C) on the betacyanin content and colour stability of betacyanins from red pitahaya (Hylocereus polyrhizus) were investigated and compared to red beet (Beta vulgaris; E‐162) which was used as a control. Temperature treatment at 50 and 85 °C caused a greater reduction in betacyanin content (BC) in E‐162 compared to red pitahaya by inducing changes in betacyanin profile. The 10 weeks of refrigerated storage at 4 °C induced colour changes in betacyanins from red pitahaya and E‐162. In milk, betacyanins from red pitahaya presented a lower loss of BC and total colour changes (ΔE*) compared to E‐162. The microbial onset in milk containing betacyanins from red pitahaya and E‐162 was delayed up to day 5 of refrigerated storage at 4 °C compared to day 3 in plain milk. Milk containing betacyanins from red pitahaya showed better colour acceptability (3.89 ± 1.89) compared to E‐162 (6.10 ± 1.71). Hence, betacyanins from red pitahaya may be a potential natural functional colourant to simulate strawberry colour in milk.     

Reduction of acrylamide and its kinetics by addition of antioxidant of bamboo leaves (AOB) and extract of green tea (EGT) in asparagine-glucose microwave heating system

ABSTRACT:  This study investigated the effect of antioxidant of bamboo leaves (AOB) and extract of green tea (EGT) on the formation and kinetics of acrylamide in an equimolar asparagine–glucose model system. The substrates spiked with AOB and EGT were microwave-heated at 180 °C and the acrylamide content in final reaction products was quantified by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). The results showed that both AOB and EGT could effectively reduce the formation of acrylamide in an asparagine–glucose microwave heating model system and achieved a maximum reduction rate when the addition levels of AOB and EGT were both 10⁻⁶ mg/mL reaction solution. To describe the kinetic behavior of acrylamide, a simplified kinetic model was optimized and relative kinetic rate constants were evaluated under isothermal conditions. The results indicated that the reduction effect of AOB and EGT on the acrylamide formation may partly be ascribed to the decrease of the formation rate constant ( k _F) in both AOB and EGT-spiked systems (43.4% and 32.3% of decrease, respectively, P < 0.05). The kinetic parameter k _E, which represents the elimination rate of acrylamide in both AOB and EGT-spiked systems, was not significantly different (6.9% of increase and 10.9% of decrease, respectively, P > 0.05). The results of the kinetic study indicated that addition of AOB and EGT could significantly reduce the formation rate constant ( k _F) of acrylamide, but could not significantly affect the elimination rate constant ( k _E) of acrylamide.     

产酒酵母的筛选鉴定及其在小曲中的应用

以采自川西南片区的10种曲样中分离出的18株酵母为研究对象,以产酒能力为主要指标,通过三级筛选得到一株优良产酒酵母Y-18,经分子鉴定确定其为酿酒酵母（Saccharomyces cerevisiae）。将其制作成纯种的酵母曲并和根霉曲进行复配试饭。结果表明,酵母Y-18在大米粉发酵培养基中的残糖含量最低,酒精度最高,分别为0.69 g/100 mL和10.3%vol;在60 g蒸熟大米中,添加酵母曲1.8 g、根霉曲0.5 g时,试饭酒精度最高（7.24%vol）、酸度适中、糖分最低。     

现代分析测试技术在印染行业的应用(十)——电感耦合等离子体(ICP)分析技术及其在纺织工业上的应用(1)

简要回顾了电感耦合等离子体（ICP）分析技术的发展历程，重点介绍了ICP技术的原理，包括ICP设备的作用原理、ICP光源的激发机理、ICP温度分布的不均匀性，ICP的环形结构和趋肤效应等。目前纺织品检测中常用的ICP分析仪器有ICP-OES（光谱仪）和ICP-MS（质谱仪）两大类，介绍了这两类系统中的高频发生器和样品引入系统，以及ICP应用中的干扰问题。采用ICP技术测定纺织品中的重金属含量，具有操作简单、测试精度高和重现性好的优点。     

Characterization of gametogenetin 1 (GGN1) and its potential role in male fertility through the interaction with the ion channel regulator, cysteine-rich secretory protein 2 (CRISP2) in the sperm tail

Cysteine-rich secretory protein 2 (CRISP2) is a testis-enriched protein localized to the sperm acrosome and tail. CRISP2 has been proposed to play a critical role in spermatogenesis and male fertility, although the precise function(s) of CRISP2 remains to be determined. Recent data have shown that the CRISP domain of the mouse CRISP2 has the ability to regulate Ca(2+) flow through ryanodine receptors (RyR) and to bind to MAP kinase kinase kinase 11 (MAP3K11). To further define the biochemical pathways within which CRISP2 is involved, we screened an adult mouse testis cDNA library using a yeast two-hybrid assay to identify CRISP2 interacting partners. One of the most frequently identified CRISP2-binding proteins was gametogenetin 1 (GGN1). Interactions occur between the ion channel regulatory region within the CRISP2 CRISP domain and the carboxyl-most 158 amino acids of GGN1. CRISP2 does not bind to the GGN2 or GGN3 isoforms. Furthermore, we showed that Ggn1 is a testis-enriched mRNA and the protein first appeared in late pachytene spermatocytes and was up-regulated in round spermatids before being incorporated into the principal piece of the sperm tail where it co-localized with CRISP2. These data along with data on RyR and MAP3K11 binding define the CRISP2 CRISP domain as a protein interaction motif and suggest a role for the GGN1-CRISP2 complex in sperm tail development and/or motility.     

菜籽饼粕中硫甙及其降解物分析中存在的问题

阐述了菜籽饼粕中硫甙的降解途径和各种毒素的存在形式,并指出目前分析测定硫甙、噁唑烷硫酮、异硫氰酸酯、腈类和硫氰酸酯等毒素中存在的一些问题,以期为今后的研究提供参考。     

氢氧化钠改性石榴皮渣(籽)膳食纤维及其组分分析

目的建立一种石榴皮渣(籽)(pomegranate marcs(seed),PMs)膳食纤维(dietary fiber,DF)的高效改性方法。方法研究Na OH浓度、液料比、改性温度和改性时间等对PMs中可溶性膳食纤维(soluble dietary fiber,SDF)得率的影响,在单因素试验的基础上,利用响应面优化改性条件,幵探讨改性对其组成和性质的影响。结果当改性条件为Na OH浓度1.5%,液料比38.5:1(m L:g),改性时间45 min,改性温度45℃时,SDF得率达到了73.58%,幵比较分析了化学组成成分。结果该改性方法速度快、效率高而且污染小,可以用于改性石榴皮渣(籽)膳食纤维。     

Characterization of aroma-impact compounds in dry jujubes (Ziziphus jujube Mill.) by aroma extract dilution analysis (AEDA) and gas chromatography-mass spectrometer (GC-MS)

Aroma-impact compounds of dry jujubes obtained from Z. jujuba Mill. cv. “tangzao” (Y1), Z. jujuba Mill. cv. “muzao” (Y2), Z. jujuba Mill. cv. “lizao” (Y3), and Z. jujuba Mill. cv. “qingrunhongzao” (Y4) were analyzed by gas chromatography-olfactometry (GC-O). The result revealed 35, 29, 34, and 33 aroma-impact volatiles in the Y1, Y2, Y3, and Y4 samples, respectively. The compounds bearing the highest FD factor in each sample were (E)-2-hexenal, (E)-2-heptenal (FD = 256) for Y1, 2,3-butanedione, (E)-2-hexenal, 2,5-dimethylpyrazine, (E)-2-heptenal and β-damascenone (FD = 64) for Y2, 2,3-butanedione and β-damascenone (FD = 256) for Y3, and 2,5-dimethylpyrazine (FD = 256) for Y4.     

橄榄油基二酰甘油油酸酯基油凝胶的物理性质及其在饼干中的应用

为开发基于双甘油酯(DAG)的油凝胶作为饼干馅料中起酥油替代品,使用橄榄油基二酰甘油油酸酯(O-DAGO)为基料油,5%的小烛树蜡(CLW)和0～35%的橄榄油基二酰甘油硬脂酸酯(O-DAGS)组合为凝胶剂制备O-DAGO基油凝胶。研究了O-DAGO基油凝胶脂肪酸组成、微观结构、固体脂肪含量、硬度及热力学性能,并将其用作饼干的油脂基质,研究了O-DAGO基油凝胶对饼干基本理化性质的影响。结果表明：O-DAGO基油凝胶的饱和脂肪酸含量(≤23.50%)低于起酥油(52.07%),O-DAGO基油凝胶主要含有油酸(>63%);当O-DAGS含量增加时,O-DAGO基油凝胶的晶体数量增加,固体脂肪含量也逐渐升高;O-DAGS含量15%的O-DAGO基油凝胶硬度(73.19 g)与起酥油(75.42 g)接近,当O-DAGS含量为25%和35%时硬度则显著大于起酥油(p<0.05);随O-DAGS含量增加,油凝胶的熔融和结晶温度升高;O-DAGS含量不超过25%的油凝胶应用在饼干中显示出与起酥油饼干相似的硬度,更低的油脂迁移率。总的来说,O-DAGO基油凝胶应用于饼干中显示出较高的...