梯度洗脱HPLC法测定盐酸克林霉素棕榈酸酯及制剂的有关物质

目的:建立梯度洗脱HPLC法测定盐酸克林霉素棕榈酸酯原料药、分散片、颗粒及干混悬剂的有关物质。方法:采用Agilent ZORBAX XDB-C8(4.6 mm×150 mm,5μm)柱,流动相A为5 mmol·L-1醋酸铵溶液-乙腈(50∶50),流动相B为乙腈,流速为1.0 mL·min-1,线性梯度洗脱,检测波长为230 nm。结果:盐酸克林霉素棕榈酸酯与10种中间体、副产物完全分离。重复性RSD为2.9%,检测限为10μg·mL-1。结论:方法简便、灵敏、重复性好,可用于本品的质量控制。     

Development of Seed-Oil Based Dried Sausages,Considering Physicochemical and Nutritional Quality and the Role of Food Neophobia

A growing number of consumers now consider the consumption of processed meat products to be an essentially unhealthy habit. Hence, the reformulation of meat products is crucial. In this regard, the aim of this study is to reformulate “fuet”, a traditional Spanish dried sausage, by replacing the pork fat with emulsified seed oils (50–50%, 25–75% and 0–100%). Four seed oils were evaluated, including commercial seeds (poppy and chia) and other seeds considered subproducts (melon and pumpkin). Physical parameters, nutritional quality and consumer evaluation of the reformulated dried sausages were analyzed. Additionally, we considered the effects of food neophobia on consumer evaluation. The resulting fuets had a higher concentration of linoleic and linolenic acids, which varied according to the oil used. In the sensory analysis, non-neophobic consumers showed higher preference for the reformulated fuets, while all consumers gave their highest ratings to the fuets produced with pumpkin seed oil.     

Properties of Chemically Combusted Calcium Carbide Residue and Its Influence on Cement Properties

Calcium carbide residue (CCR) is a waste by-product from acetylene gas production. The main component of CCR is Ca(OH)₂, which can react with siliceous materials through pozzolanic reactions, resulting in a product similar to those obtained from the cement hydration process. Thus, it is possible to use CCR as a substitute for Portland cement in concrete. In this research, we synthesized CCR and silica fume through a chemical combustion technique to produce a new reactive cementitious powder (RCP). The properties of paste and mortar in fresh and hardened states (setting time, shrinkage, and compressive strength) with 5% cement replacement by RCP were evaluated. The hydration of RCP and OPC (Ordinary Portland Cement) pastes was also examined through SEM (scanning electron microscope). Test results showed that in comparison to control OPC mix, the hydration products for the RCP mix took longer to formulate. The initial and final setting times were prolonged, while the drying shrinkage was significantly reduced. The compressive strength at the age of 45 days for RCP mortar mix was found to be higher than that of OPC mortar and OPC mortar with silica fume mix by 10% and 8%, respectively. Therefore, the synthesized RCP was proved to be a sustainable active cementitious powder for the strength enhanced of building materials, which will result in the diversion of significant quantities of this by-product from landfills.     

Simultaneous effect of vacuum and ultrasound assisted enzymatic extraction on the recovery of plant protein and bioactive compounds from sesame bran

The latest studies on the extraction of bio-components from plant materials have elaborated on novel approaches to increase yield. This study evaluated the effect of vacuum operation parameters on the recovery of protein and antioxidant compounds from sesame bran. In this context, vacuum-ultrasound assisted extraction (VU) and vacuum-ultrasound assisted enzymatic extraction (VUE) methods were carried out, and the vacuum parameters were investigated using central composite design by response surface methodology (RSM). The independent parameters were found effective on protein yield, total phenolic content and antioxidant capacity values. Optimum conditions for VU were 21 min vacuum time, 72 min restoration time and 539 mmHg vacuum pressure; and for VUE were 1.82 AU/100 g enzyme concentration, 8 min vacuum time, 68 min restoration time and 238 mmHg vacuum pressure. The protein yields increased by 31.0 and 41.6 % with VU and VUE, respectively compared to standard alkaline extraction. SEM images revealed deteriorative effects of applied extraction methods. SDS-PAGE analysis was conducted to examine detailed protein fractionation and alcalase assisted extraction revealed small protein sub-units (<18 kDa) which implies the presence of potential bioactive peptides. Additionally, LC/Q-TOF/MS analysis was performed and organic compounds in sesame bran extracts were identified.     

Anti-Fatigue Effect of a Dietary Supplement from the Fermented By-Products of Taiwan Tilapia Aquatic Waste and Monostroma nitidum Oligosaccharide Complex

The Taiwan Tilapia is an important aquaculture product in Taiwan. The aquatic by-products generated during Tilapia processing, such as fish bones and skin, are rich in minerals and protein. We aimed to explore the effect of a dietary supplement, comprising a mixture of fermented Tilapia by-products and Monostroma nitidum oligosaccharides as the raw materials, combined with physical training on exercise performance and fatigue. We used a mouse model that displays a phenotype of accelerated aging. Male senescence-accelerated mouse prone-8 (SAMP8) mice were divided into two control groups—with or without physical training—and supplemented with different doses (0.5 times: 412 mg/kg body weight (BW)/day; 1 time: 824 mg/kg BW/day; 2 times: 1648 mg/kg BW/day) of fermented Tilapia by-products and Monostroma nitidum oligosaccharide-containing mixture and combined with exercise training groups. Exercise performance was determined by testing forelimb grip strength and with a weight-bearing exhaustive swimming test. Animals were sacrificed to collect physical fatigue-related biomarkers. Mice dosed at 824 or 1648 mg/kg BW/day showed improvement in their exercise performance (p < 0.05). In terms of biochemical fatigue indicators, supplementation of 824 or 1648 mg/kg BW/day doses of test substances could effectively reduce blood urea nitrogen concentration and lactate concentration and increase the lactate ratio (p < 0.05) and liver glycogen content post-exercise (p < 0.05). Based on the above results, the combination of physical training and consumption of a dietary supplementation mixture of fermented Tilapia by-products and Monostroma nitidum oligosaccharides could improve the exercise performance of mice and help achieve an anti-fatigue effect.     

氧甲氢龙合成中伴生副产物2-(2-羟基乙氧基)-17β-羟基-2,17α-二甲基-A-失碳-5α-雄甾烷的鉴定与合成

目的为改进氧甲氢龙的合成工艺及提高产率提供实验依据。方法通过柱色谱、重结晶等方法分离纯化合成氧甲氢龙过程中发现的副产物,经IR、1H-NMR、13C-NMR、MS、元素分析、X-单晶衍射实验等分析手段确证副产物的化学结构;推测副产物的形成机制并按此机制合成该副产物。结果与结论鉴定副产物为2-（2-羟基乙氧基）-17β-羟基-2,17α-二甲基-A-失碳-5α-雄甾烷,其形成机制可能是格氏试剂形成的甲基负离子在进攻中间体（7）17位的羰基碳的同时,一部分的甲基负离子从甾体平面结构的下方进攻了2位的乙缩酮的碳原子进而生成该副产物。准确分析出副产物的化学结构及形成机制。     

Pathways of trihalomethane uptake in swimming pools

Chlorination of pool water leads to the formation of numerous disinfection by-products (DBPs), chloroform usually being most abundant. Bathers and pool guardians take up various amounts of DBPs by different pathways. Identification of different uptake paths is important in order to develop a technical strategy for swimming pool water treatment and to develop focussed technical solutions to minimize THM uptake. Basically, trihalomethanes (THMs) can be taken up by inhalation, by dermal absorption, or orally (swallowing of water). In our experimental study involving up to 17 participants we quantified the body burden resulting from exposure to three different concentrations of chloroform in water and air of an indoor swimming pool, during a 60 min exercising period. Chloroform concentration of the water was 20.7, 7.1, and 24.8 μg/l and was not influenced artificially. Corresponding air CHCl₃ concentrations were measured at two different levels (20 cm and 150 cm) and ranged from to 85 to 235 μg/m³. To dissociate the dermal exposure route from that of inhalation, THM concentrations were measured in the blood of subjects practicing in an indoor pool with and without scuba tanks, as well as in the blood of subjects walking around the pool without swimming. Chloroform concentrations were measured in blood samples before and after each exercise period. Blood chloroform concentration of participants with scuba tanks was 0.32+/−0.26 μg/l, without scuba tanks 0.99+/−0.47 μg/l, and for persons walking around the pool 0.31+/−0.25 μg/l. Our results indicate that THMs are mainly taken up over the respiratory pathway. Only about one third of the total burden is taken up over the skin. We examined the relationship between blood concentration and environmental chloroform concentrations by using linear regression models. Blood concentrations are correlated to air chloroform concentrations; correlation to water concentrations is less obvious.     

A phenolic extract from grape by-products and its main hydroxybenzoic acids protect Caco-2 cells against pro-oxidant induced toxicity

Grape/wine industry produces large amounts of by-products, however knowledge on their health-promoting qualities is limited. This study investigated the effects of a grape phenolic extract (GPE) and its phenolic compounds, gallic acid (GA) and syringic acid (SA) on human intestinal Caco-2 cells, directly or after cytotoxicity induced by tert-butylhydroperoxide (t-BOOH). Direct treatment with 0.1–10 μg/mL GPE, or 0.1–10 μM GA and SA produced no major cytotoxic effect, either changes in antioxidant defences (glutathione content, glutathione peroxidase and reductase activities) or protein damage (carbonyl groups). However, 10 μg/mL GPE, 1 and 10 μM GA and 10 μM SA decreased reactive oxygen species (ROS) production.Pre-treatment with GPE, SA and GA at the same concentrations for 20 h showed that 10 μg/mL GPE and 10 μM GA or SA significantly counteracted ROS increase induced by t-BOOH. 10 μg/mL GPE and 1–10 μM GA or 10 μM of SA significantly reduced pro-oxidant-induced cytotoxicity. 1–10 μg/mL GPE, 1–10 μM GA and 10 μM SA significantly recovered both depleted glutathione and enhanced glutathione reductase and peroxidase activities, and reduced protein oxidative damage. Therefore, treatment with realistic concentrations of GPE and its main hydroxybenzoic acids protected Caco-2 cells against induced oxidative stress.     

Cytotoxicity evaluation and antioxidant enzyme expression related to heavy metals found in tuna by-products meal: An in vitro study in human and rat liver cell lines

Heavy metals can accumulate in organisms via various pathways, including respiration, adsorption and ingestion. They are known to generate free radicals and induce oxidative and/or nitrosative stress with depletion of anti-oxidants. Tuna by-product meal (TBM) is rich in proteins and can, therefore, offer an attractive protein source for animals. This study was undertaken to assess the effects of metals present in TBM, namely cadmium (Cd), lead (Pb), and mercury (Hg), separately or in combination with oxidative stress, on cell viability. Three cell models: rat liver FTO2B, human hepatoma HepG2, and human hepatic WRL-68, were used. Cell viability was determined following exposure to various concentrations of the metals. Two antioxidant genes, catalase (CAT) and superoxide dismutase (SOD), were measured to obtain a better understanding of oxidative stress-associated gene expression. Among the metals present in TBM, only Cd at a concentration of 30 μM was noted to exhibit cytotoxic effects. This cytotoxicity was even more pronounced after co-stimulation with H₂O₂, used to mimic systemic oxidative stress. At non-toxic concentrations, Hg and Pb were noted to aggravate oxidative stress toxicity. The results further revealed that exposure to Cd, Pb, and a co-stimulation of H₂O₂ with Hg resulted in the increased expression of antioxidant gene SOD. A risk assessment of toxic contaminants in TBM indicated that food safety objectives should consider the human health impacts of foods derived from animals fed on contaminated meal and that much care should be taken when TBM is used in animal diet.     

KCl Extracted from Chlorine Bypass Dust as Activator for Plain Concrete

This study demonstrated the use of KCl separated from chlorine bypass dust (CBD) as an activator for plain concrete. The separated KCl was mixed with either ground granulated blast-furnace slag (BFS) alone, or a mixture of BFS and cement. The mixed paste of separated KCl and BFS set within 24 h, and exhibited a compressive strength of 22.6 MPa after 28 d. The separated KCl, cement, and BFS mixture exhibited a more rapid setting and a higher initial activity. Further, the compressive strength at 28 d was 57.7 MPa, which was 26.2% higher than that of the mixture without the activator. Water curing of samples with added separated KCl led to the generation of hydrocalumite, or Friedel’s salt. However, this hydrocalumite was decomposed while being cured under autoclave conditions at 180 °C. Overall, KCl was an effective activator for composite materials containing cement, and resulted in superior properties compared to mineral admixtures without an activator.