Identification of anatoxins in blue-green algae food supplements using liquid chromatography-tandem mass spectrometry

Blue-green algae (cyanobacteria) in tablets and capsules, which are marketed as health food supplements, were investigated for the presence of neurotoxins related to anatoxin-a. These neurotoxins, which are nicotinic agonists, were investigated using isocratic micro-liquid chromatography-tandem mass spectrometry (micro-LC-MS-MS). The investigated compounds were anatoxin-a and homoanatoxin-a, together with their degradation products, dihydroanatoxin-a, epoxyanatoxin-a, dihydrohomoanatoxin-a and epoxyhomoanatoxin-a which were synthesized from the parent toxins. The analytes were extracted with methanol followed by isocratic chromatography on a micro C₁₈     

活细胞传感仪在嗜酸乳酸杆菌培养过程中的应用

活细胞是嗜酸乳酸杆菌发酵过程的目标产物,但长期以来一直缺乏一种能快速、准确地检测发酵液中活细胞量的方法,本文引入了一种基于电容原理的活细胞量测量新方法,探讨了其在嗜酸乳杆菌培养过程中在线应用的可行性。研究结果表明,活细胞传感仪测定的活细胞数与平板活菌计数法测定的菌体浓度有非常好的线性关系,相关系数达0.9944,在相同的实验条件下,仪器测定数据具有较好的重复性,基于电容值计算出的比生长速率比基于CER、OUR计算出的比生长速率更可信。因此活细胞传感仪为嗜酸乳杆菌培养过程在线监测提供了一种简便、精确的方法。     

高效液相色谱-质谱法测定蓝藻中的微囊藻毒素

微囊藻毒素是由淡水蓝绿藻产生的一类最常见的环七肽缩肝毒素,对动物及人类健康具有较大的危害性。本文以实验室培养铜绿微囊藻为原料,建立了固相萃取富集微囊藻毒素,液相色谱-电喷雾电离质谱测定藻样中的微囊藻毒素MC-LR的方法。该法绝对检出限为25pg,回收率为70%以上,方法灵敏度高,实用性强。在此方法的基础上,对实际藻样中的微囊藻毒素进行了定性分析。结果表明,该藻样含有MC-RR及可能为[Dha]-MC-HtyR、MC-YR、[D-Asp3]-MC-HtyR或[D-Asp3,Dhb7]-MC-HtyR的单体。     

Volatile profiles of Cabernet Gernischet wine under rain-shelter cultivation and open-field cultivation using solid-phase micro-extraction–gas chromatography/mass spectrometry

The volatile profiles of Vitis vinifera cv. Cabernet Gernischet wines in vintages 2010 and 2011 from rain-shelter cultivation and open-field cultivation were compared and detected by headspace solid phase micro-extraction with gas chromatography-mass spectrometry. The results showed that the number and concentration of volatile compounds quantified in wine were lower under rain-shelter cultivation compared with open-field cultivation. The strength of the fruity, fatty, caramel, and floral aromas of the 2010 vintage wines was lower under rain-shelter cultivation condition, and the compounds contributing to herbaceous aroma series were also lower with rain-shelter cultivation in the 2011 vintage wines. However, the strength of fruity, fatty, caramel, floral, and chemical aromas was higher with rain-shelter cultivation in vintage 2011. The cultivations in the two vintages could be clearly divided into three groups by principal component analysis. The difference between two treatments was significant in vintage 2010, whereas there was no significant difference in vintage 2011. The present work reveals the effects of rain-shelter cultivation on Cabernet Gernischet wine volatile compounds and explains that the technique is helpful in improving the wine quality in some rainy regions.     

Characterisation of the microbial population at different stages of Kefir production and Kefir grain mass cultivation

Kefir is a fermented milk that is produced by adding Kefir grains, consisting of bacteria and yeasts, to milk. The aim of this study was to determine the microbial population at different stages of traditional Kefir production and Kefir grain mass cultivation. Seven different selective growth media, morphological and biochemical characteristics were used for the isolation and identification of the microbes. The microbial numbers during Kefir production varied between 4.6×10³ and 2.6×10⁸. A Zygosaccharomyces sp. was isolated from traditional Kefir grains and after the culturing conditions applied during the mass cultivation Candida lambica and C. krusei were present. Although these two species are present in other fermented milks, this study is the first to report their presence in Kefir. Species of Leuconostoc, Lactococcus, Lactobacillus and Cryptococcus were isolated from traditional grains. Lactobacillus plantarum was present in the mass cultivated grains, but not in the traditional Kefir grains.     

藻类光生物反应器的设计及应用研究

根据藻类的生长特点设计了一个容积为10.0L的光生物反应器,其长×宽×高分别为320mm×80mm×390mm。利用该反应器进行螺旋藻培养实验,采用响应面法对其培养条件进行优化研究,建立以藻体干重为响应值,以光照强度、通气量、培养时间和装液量为自变量的二次多项式数学模型。培养条件优化后螺旋藻最终干重为1.298g/L。实验结果表明,所设计的反应器能很好地满足藻类生长,其培养产率也明显提高。      

梅鹿辄优质高效栽培技术

我公司自1998年4月上旬定植优质酿酒葡萄梅鹿辄,至2002年已有5个年头,通过广大技术人员的不断探索总结及广大种植户的积极配合,摸索出一套良种良法优质高效栽培技术规范措施,现介绍如下。1 高标准建园1.1 园地选择以砾质红壤地最好,红壤,黄壤次之,在微酸性土壤(pH6～7)上生长最好,pH4.8～8之间也能生长。优选缓坡地(坡度在5～15度最好)、南坡、西南坡,丘陵低平山地的北坡也可以,但避免在高的阴坡、沟底局部低洼地段建园,以免晚霜危害。1.2 行向、株行距及架式的确定行向:平坝、地改田,一般采用南北行向;缓坡地、小丘陵一般采用与等高线…     

京亚葡萄大粒无核栽培技术

京亚葡萄在自然情况下,坐果率较低,果穗较小,穗形稀疏,果粒大小不整齐,外观不美,商品性较差,严重影响了其栽培效益.作者自1998年开始进行京亚等葡萄品种的大粒无核化栽培试验,结果表明:采用无核化栽培技术可使京亚葡萄的无核果率达97%以上,成熟期提前7天左右,坐果率提高1倍以上,平均果粒重6.0g左右,且大小均匀,果穗重500g左右,可溶性固形物含量14%～15%,果实硬度增强,口感较脆,2001～2004年市场批发价为3.0元/kg,有核果实为1.6～2.0元/kg,每667 m2可增值1000～1500元.其栽培技术要点如下.     

超高效液相色谱-串联质谱法同步测定贝类水产品中4种脂溶性藻毒素

目的建立一种超高效液相色谱-串联质谱法同时测定贝类产品中4种脂溶性藻毒的方法。方法样品采用甲醇均质提取,用HLB小柱净化,在乙腈-5 mmol/L醋酸铵水溶液体系中,经Kinetex C_(18)柱(150 mm×3 mm,2.6μm)梯度洗脱,实现了4种藻毒素的良好分离。采用了电喷雾正负离子同时监测模式对4种脂溶性藻毒素进行外标法定量测定。结果目标化合物的检出限为2.3～20.7 pg/g,在3.8～1378.0 pg/g浓度范围内线性良好,相关系数r~2在0.99407-0.99923之间,同时以贝类产品为基底的4种化合物在高、中、低3个加标水平浓度下的回收率为70%～95%,相对标准偏差(relative standard deviation,RSD)为2.3%～7.7%。结论该方法灵敏、准确、高效,适合用于贝类水产品食用安全的日常风险监测项目中。     

海藻悬浮饮料的研制

以海藻粉为原料,通过一系列工序加工成一种新型的悬浮饮料.结果表明采用瞬时灭菌对饮料的加工更有利,同时确定了添加剂的加入方法.     

藻油的微胶囊化

以大豆分离蛋白和麦芽糊精为壁材,采用喷雾干燥法对藻油进行微胶囊包埋。通过单因素实验考察不同配方和工艺参数,采用正交实验设计优化各因素,得到包埋的最优工艺为:大豆分离蛋白与麦芽糊精比例1∶2,固形物含量15%,芯壁比1∶2,单硬脂酸甘油酯和蔗糖脂肪酸酯(3∶7)用量为3%,喷雾干燥进风温度170℃,出风温度70℃,均质压力45 MPa,微胶囊包埋效率可达92.8%。在最佳工艺条件下获得的藻油微胶囊产品感官品质较好,在保持低水分含量的同时兼具良好的溶解性和氧化稳定性。     

The food security challenge of the food-land-water nexus in India

Two of the key factors that drive agricultural growth and food production in India are access to arable land and utilizable water resources. These are examined with particular reference to their regional variation in order to make an assessment of the magnitude of the food security challenge they pose for the country. Recent official estimates of groundwater exploitation in India are compared with actual negative physical, social and economic consequences of over-exploitation, as are evident in different regions, and their implications for national food security discussed. The analyses show that the real food security and water management challenge lies in the mismatch between water availability and agricultural water demand: high demands occur in water scarce but agriculturally prosperous regions and low demands in naturally water-abundant but agriculturally backward regions. Serious groundwater depletion problems, which occur in the naturally water-scarce but surplus food-producing regions, magnify the challenge. The small area of arable land per capita is a major reason for low agricultural water demand in regions that have abundant water. Sustainability of well irrigation in the naturally water-scarce regions, which is the backbone of India??s food security, could be achieved through judicious investment in surface water projects which encourage direct irrigation and replenishment of over-exploited aquifers. Other strategies include: pro rata pricing of electricity in the farm sector; volumetric pricing of water from public irrigation systems; improving the efficiency of utilization of green water or the rainwater held in the soil profile; preventing depletion of the residual soil moisture in the field after crop harvest by reducing the fallow period; and reducing the use of water through a shift to low water consuming crops     

利用溶胶-凝胶将海藻固定于纤维以获得生物功能材料

利用溶胶-凝胶涂料可以把微海藻和碾碎的海藻固定在纤维和织物上.通过该方法将海藻的生物功能性固定在织物上,并得到生物功能化的织物,用于生物反应器、水处理和抗微生物功能织物领域,应用前景极佳.     

加强实践教学 培养创新人才

在实践教学中,围绕中药资源与开发专业人才的培养,讨论了实验教学、毕业设计、实习和实训基地建设、大学生社会实践活动及大学生科学研究在培养创新人才过程的作用和意义。     

植物乳杆菌富硒培养条件的优化

为提高植物乳杆菌（Lactobacillus plantarum Lb-30）的硒含量,满足人们对于微量元素硒的日常膳食需求,以改良MRS为基础培养基进行富硒培养,先确定最适亚硒酸钠浓度,研究不同发酵时间、加硒时间、初始p H、接种量对菌体硒含量的影响。在单因素实验基础上采用Box-behnken设计对富硒培养条件进行优化。得到最优富硒培养条件组合方案为:亚硒酸钠浓度5.0μg/m L、加硒时间7.6 h、初始p H5.5、接种量3.0%、培养时间36.0 h。优化后,植物乳杆菌LB-30硒含量高达839.635μg/g,比优化前655.95μg/g提高了1.28倍。结论:将为富硒植物乳杆菌的生产开发提供一定的理论依据。