New mechanisms and therapeutic potential of curcumin for colorectal cancer

Curcumin is a polyphenol derived from Curcuma longa. Over the last few years, a number of studies have provided evidence of its main pharmacological properties including chemosensitizing, radiosensitizing, wound healing activities, antimicrobial, antiviral, antifungical, immunomodulatory, antioxidant and anti-inflammatory. More recent data provide interesting insights into the effect of this compound on cancer chemoprevention and chemotherapy. In fact, preclinical studies have shown its ability to inhibit carcinogenesis in various types of cancer including colorectal cancer (CRC). Curcumin has the capacity of interact with multiple molecular targets affecting the multistep process of carcinogenesis. Also, curcumin is able to arrest the cell cycle, to inhibit the inflammatory response and the oxidative stress and to induce apoptosis in cancer cells. Likewise, it has been shown to possess marked antiangiogenic properties. Furthermore, curcumin potentiates the growth inhibitory effect of cyclo-oxygenase (COX)-2 inhibitors and traditional chemotherapy agents implicating another promising therapy regimen in the future treatment of CRC. However, its clinical advance has been hindered by its short biological half-life and low bioavailability after oral administration. This review is intended to provide the reader an update of the bioavailability and pharmacokinetics of curcumin and describes the recently identified molecular pathways responsible of its anticancer potential in CRC.     

Exploring solid lipid nanoparticles to enhance the oral bioavailability of curcumin

Scope : Curcumin, a molecule with pluripharmacological properties, was loaded into solid lipid nanoparticles (SLNs) with a view to improve its oral bioavailability (BA). Methods and results : Curcumin‐loaded solid lipid nanoparticles (C‐SLNs) with an average particle size of 134.6 nm and a total drug content of 92.33±1.63% was produced using a microemulsification technique. The particles were spherical in shape, with high drug entrapment of 81.92±2.91% at 10% drug loading. The in vitro release was predominantly by diffusion phenomenon and was prolonged up to 7 days. No significant variation in particle size and curcumin content of C‐SLNs was observed, upon storage, over a period of 12 months at 5±3°C. In vivo pharmacokinetics performed after oral administration of C‐SLNs (50, 25, 12.5 and 1 mg/kg dose) and (free) solubilized curcumin (C‐S; 50 mg/kg), using a validated LC‐MS/MS method in rat plasma revealed significant improvement (at p<0.05) in BA (39 times at 50 mg/kg; 155 times at 1 mg/kg; and, 59 and 32 times at 12.5 and 25 mg/kg, respectively) after administration of C‐SLNs at all the doses with respect to C‐S. Conclusions : Enhanced and reliable BA will help in establishing its therapeutic usefulness especially for neurodegenerative and cancerous disorders in humans.     

The stabilizing behaviour of soybean soluble polysaccharide and pectin in acidified milk beverages

The mechanisms of stabilization of soybean soluble polysaccharide (SSPS) and high methoxyl pectin (HMP) in acidified milk drinks were studied focusing on the differences in behaviour between the two polysaccharides. The changes in casein micelles size during acidification with glucono-δ-lactone or by direct acidification were measured using light scattering. When HMP was added to skim milk before acidification, pectin adsorbed on the surface of the casein micelles via electrostatic interactions and prevented casein aggregation. Results suggested that adsorption of pectin occurred from the beginning of acidification and somewhat affected the rearrangement of casein micelles in the pH range between 5.8 and 5.0. On the other hand, SSPS, at concentrations up to 2% (w/w), did not interact with caseins at pH >4.6. At pH <4.2 SSPS showed better stabilizing properties than HMP. In addition, between pH 4.2 and 3.2, SSPS-stabilized acid dispersions were not affected by pH, while dispersions homogenized with pectin showed a size distribution that depended on pH. The differences in structure between SSPS and HMP account for the unique functionalities of the two polysaccharides in acid milk systems.     

水溶性大豆多糖和果胶作为酸性乳饮料稳定剂的研究

通过改变酸性乳饮料的加工工艺比较了大豆多糖和果胶在稳定酸性乳饮料时的差异.结果表明,温度和调酸的顺序对添加了大豆多糖的酸性乳饮料稳定性的影响比对添加了果胶的酸性乳饮料稳定性的影响更为显著.在0℃时调酸和调酸之后均质的条件下,添加有0.40%大豆多糖的酸性乳饮料的稳定性最好,沉淀率最低为0.69%;而添加有0.35%果胶的酸性乳饮料的沉淀率为0.71%.而且进一步验证了大豆多糖能在pH值为3.4～4.4范围内稳定酸性乳饮料,而果胶只能在pH值为3.6～4.4范围内稳定酸性乳饮料.     

Oxidation stability of the lipid fraction in milk powder formulas

The purpose of this study was to predict the shelf life of distinct milk powder formulas by measuring hydroperoxides, headspace volatile compounds (propanal, pentanal and hexanal), fatty acid content, and sensory quality. The oxidation stability of three formulas was followed over 15 months of storage at 25 and 37 °C. These formulas were a non-supplemented formula (NSF), and two formulas supplemented with n − 3 and n − 6 long-chain polyunsaturated fatty acids, a formula with 0.83 and 0.47% (SFA), and one with 27.8 and 3.51% of n − 3 and n − 6 long-chain polyunsaturated fatty acids (SFB), respectively. Relative stability decreased in the order NSF at 25 °C > SFA at 25 °C ? SFA at 37 °C ? SFB at 25 °C > SFB at 37 °C. Therefore, we conclude that the polyunsaturated fatty acid content, storage temperature and storage time are very important factors for determining the oxidation stability.     

牛奶粉上火机理研究

以添加了20%全脂奶粉的全价饲料为原料,研究了全脂奶粉对SD大鼠免疫器官指数、血液生化与血细胞指标及血清细胞因子的影响,探讨了饮食牛奶粉的上火机理.结果表明,在丙二醛、尿素氮质量分数及中间细胞数与中性粒细胞数上,全脂奶粉组均显著高于对照组;在超氧化物歧化酶质量分数及白细胞数与淋巴细胞数上,全脂奶粉组雄性大鼠显著高于对照组:在血清碱性磷酸酶质量分数上,全脂奶粉组显著低于对照组;在脾指数、胸腺指数、总蛋白、白蛋白、血糖、总胆固醇、天门冬氨酸氨基转移酶、丙氨酸氨基转移酶、Na+-K+-ATP酶、红细胞敷、血红蛋白、粒细胞百分比及白细胞介素-2等质量分数上,组间差异均不显著.提示肠道黏膜细胞与牛奶成分相作用可导致局部微炎症.     

Structures and some properties of soluble protein complexes formed by the heating of reconstituted skim milk powder

The effects of heat on reconstituted skim milk powder (RSMP) at a temperature of 90 °C have been determined, with respect to the formation of soluble protein complexes. Heating at the natural pH of the RSMP forms soluble complexes in the milk serum, which can be separated by size exclusion chromatography. The diameters of the particles were found to be up to 50 nm, as shown by light scattering and by scanning electron microscopy. The formation of the soluble complexes was strongly affected by the treatment of the RSMP before heating. Treatment of the milk with small amounts of glutaraldehyde, to fix the casein micellar structure, severely inhibited the formation of the soluble complexes. The pH at which the milk was heated (in the range 6.5–7.2) also had an effect on the amounts and the sizes of the complexes, as determined by size exclusion chromatography. The amount of soluble complex present in the RSMP affected the strength of the acid gels produced from the different milks, as was shown by exchanging the sera of milks treated differently with glutaraldehyde, and by following the gelation of milks heated at different pH values. Increased amounts of soluble complexes gave stronger acid gels. However, the relationship appeared to break down if milk was heated at pH 7.2, where the soluble material appeared to change and the acid gel was much weaker.     

奶粉干燥设备的现状及其研究进展

结合目前我国所使用的奶品干燥设备及国内外干燥技术和干燥机的现状 ,对奶粉干燥设备———喷雾干燥设备的现状、应用及发展方向作了简述。     

Optimising water activity for storage of high lipid and high protein infant formula milk powder using multivariate analysis

High lipid and high protein infant formula milk powders were stored at water activity of 0.11, 0.33 and 0.53 for up to fourteen weeks at 40 °C to investigate the effect of storage water activity on physicochemical properties and formation of volatiles to thereby recommend optimal storage water activity conditions. Water activity of the powders was determined during storage together with surface colour, glass transition temperature combined with dynamic headspace sampling followed by gas chromatography/mass spectrometry. The principal component analysis (PCA) showed that the optimal water activity for storage of high lipid infant formula milk powder, for which lipid oxidation was found to be the critical quality parameter, is a_w = 0.33 with lowest lipid oxidation, while for high protein infant formula milk powder, for which protein degradation was found to be the critical quality parameter, a_w = 0.11 is optimal to limit formation of Maillard reaction products.     

The kinetics of Maillard reaction in lactose-hydrolysed milk powder and related systems containing carbohydrate mixtures

The kinetics of Maillard reaction in lactose-hydrolysed skim milk powder and related systems containing carbohydrate mixtures were analysed. The effect of the increase of water activity and temperature during storage of the commercial product was also evaluated. In systems with two and three carbohydrates, a marked decrease of the reaction rate was observed when monosaccharides were partially replaced by lactose, notwithstanding the fact that the former still remained in a higher proportion than lysine. The rate of available lysine loss in lactose-hydrolysed milk was mostly affected by the presence of galactose. The reaction rate constants at a_w 0.52 and at 37 and 50 °C were higher than at a_w 0.33. However, no significant differences were observed at 60 °C. Temperature is the most important factor to be controlled in order to minimise nutritional deterioration during storage.     

姜黄素与茶多酚联用固体脂质纳米粒的制备及抗肿瘤活性研究

采用薄膜-超声法制备姜黄素与茶多酚联用的固体脂质纳米粒,采用HPLC-DAD法建立了纳米粒中姜黄素和茶多酚类共5个活性成分的同步含量测定方法,考察了联用固体脂质纳米粒在不同储存条件下的稳定性,并对其抗肿瘤活性进行了研究。结果表明:当配方为姜黄素与茶多酚联用混合物（含量比例1∶1）40 mg,硬脂酸120 mg,卵磷脂60 mg,吐温-80（1.0%）10 m L时,所得固体脂质纳米粒平均粒径为93.8 nm,多分散度（polydispersity index,PDI）0.172,Zeta电位为-44.5 m V,平均包埋率达到93.08%,载药量为12.81%;姜黄素和茶多酚类5个活性成分在4℃条件下储存稳定性良好;MTT法实验结果表明联用固体脂质纳米粒对Hep G2和A549肿瘤细胞较姜黄素、茶多酚单独给药有更强的肿瘤细胞抑制作用（p<0.05）。结果证明,姜黄素与茶多酚联用制备固体脂质纳米粒的工艺合理可行,包埋率高,粒度均匀,稳定性好,对肿瘤细胞具有明显的协同抑制作用。姜黄素与茶多酚两种天然酚类活性成分的联用在食品工业领域具有极大的潜力。      

The pectin substance used to detect the activity of pectinase suitable for bioscouring

Structural characteristics of pectins from cotton fabrics, ramie, and apple were investigated by titration method and ATR–FTIR spectra. Pectin from cotton fabrics and ramie showed similar structure characteristics, both these two pectins showed big structural difference with pectin from apple. The activities of five pectinases were determined by using these three pectins as substrates. These five pectinases showed similar hydrolysis action on pectin from ramie and cotton fabrics, they also showed a great difference in the hydrolysis of pectin from apple and cotton fabrics. Moreover, bioscouring effect with these five pectinases was investigated, the pectinases with stronger hydrolysis action on ramie pectin displayed better bioscouring effect and the pectinase suitable for bioscouring was selected out. The bioscouring effect of the pectinase selected out was studied and showed almost perfect bioscouring effect.     

An alternative process for the manufacture of whole milk powder

The traditional process of manufacturing whole milk powder has some negative aspects: high heat treatment of the milk and, owing to fouling during evaporation, loss of product. To reduce these negative aspects an alternative way of producing whole milk powder was investigated in pilot-plant experiments. Milk was first separated into skim milk and cream and then treated further. Skim milk was subjected to a low heat treatment and concentrated by evaporation. The cream was subjected to a high heat treatment and mixed with the concentrated skim milk. The standardized whole milk concentrate was then spray dried. This process of manufacturing whole milk powder compared favourably with the traditional process with respect to product losses, the physical properties of the whole milk powder and the flavour of the reconstituted milk.     

奶粉中DHA测定方法的探讨

介绍了DHA的生理功能及奶粉中DHA的测定方法。结合实际工作经验．探讨了影响DHA测定结果的因素，并对建立奶粉中DHA测定方法提出了建议。     

试剂盒法测定乳粉中的维生素

通过对国家标准GB 5413-2010和德国拜法公司微生物法测维生素试剂盒说明书的研究,做对比试验,两种检测方法差异率小于10%。找出试剂盒标准曲线的实际质量分数,绘制出标准曲线,定出实验室适用的试剂盒方法。     

蛋白粉和奶粉的鉴伪技术研究进展

蛋白粉和奶粉是孕妇和婴儿特别关注的一类食品,但其中的掺假现象十分严重,而且掺假方式多种多样,这严重威胁到消费者的人身健康。本文对其中非蛋白成分(三聚氰胺等)、异源蛋白(大豆蛋白等)、乳源性蛋白(乳清粉等)和非乳脂肪等掺假物质的检测方法进行重点总结,并对各种鉴伪方法的优劣进行对比。      

可溶性丝素蛋白粉生产新工艺

研究了制备可溶性丝素蛋白粉的新方法。以废蚕丝为原料,经0.5％（w/v）的Na₂CO₃溶液精炼后,用40％（w/w）的CaCl₂溶液溶解丝素蛋白,采用渗析器脱盐,得到的丝素蛋白溶液喷雾干燥后即制得可溶性丝素蛋白粉,并测定了产品的氨基酸组成和相对分子质量分布。      

功能性中老年奶粉的研制

对中老年奶粉进行了润肠通便调理胃肠的保健功能研究。动物实验结果表明，饲喂中老年奶粉的动物组肠运动试验呈阳性（P＜0．05）；动物实验组较对照组排便量明显增加、粪便软化、水分含量高。本研究为中老年功能性奶粉的开发，提供了可靠的参考依据。     

同时蒸馏萃取法和固相微萃取法提取羊奶粉挥发性风味物质

采用固相微萃取法和同时蒸馏萃取法提取羊奶粉中的挥发性成分,再经气相色谱-质谱联用仪分析,共检出风味化合物55种,SPME法检出41种,SDE法检出22种,其中共同检测到8种,分别是辛酸、壬酸、癸酸、月桂酸、十二内酯、十四烷、十五烷、2-壬酮。SPME法和SDE法结合使用能较为全面的反映出羊奶粉的挥发性风味物质,且羊奶粉的挥发性风味物质以挥发性酸类成分为主。     

同时蒸馏萃取法和固相微萃取法提取羊奶粉挥发性风味物质

采用固相微萃取法和同时蒸馏萃取法提取羊奶粉中的挥发性成分,再经气相色谱-质谱联用仪分析,共检出风味化合物55种,SPME法检出41种,SDE法检出22种,其中共同检测到8种,分别是辛酸、壬酸、癸酸、月桂酸、十二内酯、十四烷、十五烷、2-壬酮。SPME法和SDE法结合使用能较为全面的反映出羊奶粉的挥发性风味物质,且羊奶粉的挥发性风味物质以挥发性酸类成分为主。