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1.
新型食品防腐剂山梨酸   总被引:9,自引:0,他引:9  
盛丽  苏碧泉 《化学教育》2004,25(7):8-10,15
防腐剂是能抑制微生物生长、防止食品腐败变质、延长保存期的一类添加剂。山梨酸在人体内能参加正常的新陈代谢,可视做食品的成分之一,是迄今为止国际公认的最好食品防腐剂。山梨酸可用乙烯酮巴豆醛法、丁二烯乙酸法合成。  相似文献   

2.
Two New Age foods which contain high concentrations of whole food nutrients are the single-celled microalgae Chlorella and Spirulina. They are accepted as functional foods, which are defined as products derived from natural sources, whose consumption is likely to benefit human health and enhance performance. These foods are used as a supplement/ingredient or as a complete food to enhance the performance and state of the human body, or improve a specific bodily function. Functional foods are used mainly as products to nourish the human body after physical exertion or as a preventive measure against ailments. We determined the fatty acid compositions, particularly polyunsaturated fatty acid compositions, of Chlorella and Spirulina by capillary column-gas chromatography. The data obtained show that Spirulina contains unusually high levels of gamma-linolenic acid, an essential polyunsaturated fatty acid.  相似文献   

3.
Overweight, obesity, and psychiatric disorders are serious health problems. To evidence the anxiolytic-like effects and lipid reduction in mice receiving a high-calorie diet and Bertholletia excelsa seeds in a nonpolar extract (SBHX, 30 and 300 mg/kg), animals were assessed in open-field, hole-board, and elevated plus-maze tests. SBHX (3 and 10 mg/kg) potentiated the pentobarbital-induced hypnosis. Chronic administration of SBHX for 40 days was given to mice fed with a hypercaloric diet to determine the relationship between water and food intake vs. changes in body weight. Testes, epididymal white adipose tissue (eWAT), and liver were dissected to analyze fat content, triglycerides, cholesterol, and histological effects after administering the hypercaloric diet and SBHX. Fatty acids, such as palmitoleic acid (0.14%), palmitic acid (21.42%), linoleic acid (11.02%), oleic acid (59.97%), and stearic acid (7.44%), were identified as constituents of SBHX, producing significant anxiolytic-like effects and preventing body-weight gain in mice receiving the hypercaloric diet without altering their water or food consumption. There was also a lipid-lowering effect on the testicular tissue and eWAT and a reduction of adipocyte area in eWAT. Our data evidence beneficial properties of B. excelsa seeds influencing global health concerns such as obesity and anxiety.  相似文献   

4.
Significant effort focused on developing photoactivatable theranostics for localized image guided therapy of cancer by thermal ablation. In this context iron complexes were recently identified as photoactivatable theranostic agents with adequate biocompatibility and body clearance. Herein, a series of FeII complexes bearing polypyridine or N-heterocyclic carbenes is reported that rely on rational complex engineering to red-shift their MLCT based excited-state deactivation via a straightforward approach. The non-radiative decay of their MLCT upon irradiation is exploited for theranostic purposes by combining both tracking in photoacoustic imaging (PA) and photothermal therapy (PTT). The influence of structural modifications introduced herein on the solubility and stability of the complexes in biorelevant aqueous media is discussed. The relationship between complexes’ design, production of contrast in photoacoustic and photothermal efficiency are explored to develop tailored PA/PTT theranostic agents.  相似文献   

5.
Looking inside the human body fascinated mankind for thousands of years. Current diagnostic and therapy methods are often limited by inadequate sensitivity, specificity and spatial resolution. Raman imaging may bring revolution in monitoring of disease and treatment. The main advantage of Raman imaging is that it gives spatial information about various chemical constituents in defined cellular organelles in contrast to conventional methods (liquid chromatography/mass spectrometry, NMR, HPLC) that rely on bulk or fractionated analyses of extracted components. We demonstrated how Raman imaging can drive the progress on breast cancer just unimaginable a few years ago. We looked inside human breast ducts answering fundamental questions about location and distribution of various biochemical components inside the lumen, epithelial cells of the duct and the stroma around the duct during cancer development. We have identified Raman candidates as diagnostic markers for breast cancer prognosis: carotenoids, mammaglobin, palmitic acid and sphingomyelin as key molecular targets in ductal breast cancer in situ, and propose the molecular mechanisms linking oncogenes with lipid programming.  相似文献   

6.
Ratnam DV  Bhardwaj V  Kumar MN 《Talanta》2006,70(2):387-391
Antioxidants are gaining tremendous interest as chemopreventive as well as chemotherapeutic agents. Ellagic acid (EA) is a plant derived compound with very poor solubility in water and very low octanol/water partition coefficient and coenzyme Q10 (CoQ10) is a highly lipophilic compound, which is synthesized in the body and can be derived from food supplements as well. The new insights in the combination therapy are promising a better future in many challenging diseases. Synergism is among the key advantages of combination therapy apart from decreased intensity of unwanted effects of a compound, increased patient compliance and reduction in cost of therapy. EA and CoQ10 supplementation in combination will be beneficial in strengthening the weakened antioxidant defense system in many diseases related to oxidative stress. Here we report first derivative UV spectroscopic and HPLC methods for the simultaneous analysis of these two agents in pharmaceutical preparations. Results obtained indicate that the derivative spectroscopy is as efficient as HPLC method in quantitative analysis. Retention of ellagic acid can be increased using PEG bonded column which is poorly retained on C18 column. PEG column can be used for rapid simultaneous analysis of EA and CoQ10, which are having diverse physicochemical properties.  相似文献   

7.
New stable isotope dilution assays were developed for the simultaneous quantitation of [13C5]-labelled and unlabelled 5-methyltetrahydrofolic acid, 5-formyltetrahydrofolic acid, folic acid along with unlabelled tetrahydrofolic acid and 10-formylfolic acid in clinical samples deriving from human bioavailability studies, i.e. plasma, ileostomy samples, and food. The methods were based on clean-up by strong anion exchange followed by LC-MS/MS detection. Deuterated analogues of the folates were applied as the internal standards in the stable isotope dilution assays. Assay sensitivity was sufficient to detect all relevant folates in the respective samples as their limits of detection were below 0.62 nmol/L in plasma and below 0.73 μg/100 g in food or ileostomy samples. Quantification of the [13C5]-label in clinical samples offers the possibility to differentiate between folate from endogenous body pools and the administered dose when executing bioavailability trials.  相似文献   

8.
硒与癌症   总被引:6,自引:0,他引:6  
硒是人体必需微量元素。流行病学调查表明。土壤硒含量,谷物硒含量。食物硒摄入量及人体血硒水平与多种癌症发病率(死亡率)呈负相关,动物实验证实,适量硒具有抑癌抗癌作用,硒抗癌机理研究及人体干预试验进一步说明硒与癌症关系密切。  相似文献   

9.
Cancer biomarker refers to a substance or process that is indicative of the presence of cancer in the body. A biomarker might be either a molecule secreted by a tumor or it can be a specific response of the body to the presence of cancer. Cancer biomarker-based diagnostics have applications for establishing disease predisposition, early detection, cancer staging, therapy selection, identifying whether or not a cancer is metastatic, therapy monitoring, assessing prognosis, and advances in the adjuvant setting. Full adoption of cancer biomarkers in the clinic has to date been slow, and only a limited number of cancer biomarker products are currently in routine use.Among proteomic technologies, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS) is a technique that has allowed rapid progress in cancer biology. Different further developed methods including e.g. SELDI (surface-enhanced laser desorption/ionization) and MELDI (material-enhanced laser desorption/ionization) are simple and high-throughput techniques that analyze with high sensitivity and specificity intact proteins expressed in complex biological mixtures, such as serum, urine, and tissues. The combination of mass spectrometry (MS) with infrared (IR) spectroscopic imaging is an attempt to combine different technologies in systems analytics. Both MALDI-TOF and infrared tissue imaging enable studying proteins distribution in tissue samples with a resolution down to 50 and 5 μm, respectively.In this review, we summarize recent applications and the synergistic combination of these new technologies to proteomic profiling for cancer biomarker discovery.  相似文献   

10.
Nandrolon is an androgenic growth promoter. This anabolic substance can be used for accelerating the increase of animal body mass. This steroid is used also in the therapy of animals like cattle, sheep or hogs and it can be found as residuum in the animal body. In a lot of countries this therapy is used abusively and, as result, results in a high level of residuals in different food stuffs such as beef and pork meat and veal liver. Because of these potential health damages it is important to monitor the food concerning the hormonal residuals. Due to their very low concentration in animal products, these chemical compounds can be determined only using ELISA and RIA immunochemical analysis techniques. In this paper, we describe the methods of obtaining tritium-labeled nandrolone for RIA kits production.  相似文献   

11.
Lactoferrin is an iron binding glycoprotein with multiple roles in the body. Its participation in apoptotic processes in cancer cells, its ability to modulate various reactions of the immune system, and its activity against a broad spectrum of pathogenic microorganisms, including respiratory viruses, have made it a protein of broad interest in pharmaceutical and food research and industry. In this review, we have focused on describing the most important functions of lactoferrin and the possible mechanisms of action that lead to its function.  相似文献   

12.
Abstract

Most organic acids in physiological fluids are carboxylic acids or their glycine or glucuronide conjugates. Also included are hydroxyl compounds, such as phenols or cresols. By definition, compounds with a primary amino group, detectable by conventional amino acid analysers, are excluded. Organic acids are produced continuously in the body as intermediates in the metabolism of amino acids, carbohydrates and fats, and of drugs and food additives. They do not accumulate in the body, since they are rapidly converted to non-acidic end products or excreted as water soluble metabolites i n urine. However, if they are produced in excess, or if their metabolism is prevented by an inherited enzyme defect, concentrations increase in the tissues, blood and urine. Examples of excessive production are during fasting ketosis, in which acetoacetic and 3-hydroxybutyric acids and a range of dicarboxylic acids derived from breakdown of fatty acids accumulate, and lactic acidosis, secondary to hypoxia, when increases in lactic, pyruvic and 2-hydroxybutyric acids are common.  相似文献   

13.
《中国化学快报》2021,32(12):3687-3695
Cancer is a serious threat to humans due to its high mortality. The efforts to fully understand cancer and to fight against it have never been stopped. The traditional therapies, such as surgery, radiotherapy and chemotherapy, are useful but cannot meet the increasing demands of patients. As such, novel approaches against cancer are urgently required. It has been found that the acidic tumor microenvironment plays important roles in promoting the cancer progression. In recent years, sodium bicarbonate (NaHCO3), a simple inorganic salt, has been found to be able to reverse the pH of tumor microenvironment and inhibit the invasion, metastasis, immune evasion, drug resistance and hypoxia of tumor cells. Thus, NaHCO3-based therapy is a potential approach for the treatment of cancer, and the related studies have been increasingly reported. Herein, we aim to provide a comprehensive understanding of the acidic tumor microenvironment and summarize the applications and mechanisms of NaHCO3 in cancer therapy. The combination of NaHCO3 with chemotherapy, immunotherapy or nanoparticles systems is discussed. In addition, the concerns of NaHCO3 in clinical use and the potential ways to use NaHCO3 for cancer therapy are also discussed.  相似文献   

14.
5‐Hydroxymethylfurfural (5‐HMF) is a natural occurring substance taken up by everyday food. In former studies it was shown that 5‐HMF is completely decomposed in the body after oral or intravenous application resulting in three main metabolites named 5‐hydroxymethylfuroic acid, 2,5‐furandicarboxylic acid, and N‐(hydroxymethyl)furoyl glycine, and possibly a forth metabolic substance, termed 5‐sulphoxymethylfurfural, is formed. Determination is possible via HPLC using a hydrophilic interaction chromatography (HILIC) column with an appropriate gradient system (ACN/ammonium formate 100 mM, pH 2.35). Urine samples were purified by use of an SPE method beforehand working with ScreenA cartridges. This cleaning procedure was validated based on ICH guidelines in terms of linearity, quantification, and detection limit, as well as precision, repeatability, and accuracy. Analysis of real‐life samples coming from two healthy probands and one cancer patient, who all received 240 mg 5‐hydroxymethylfurfural orally once a day, showed dicarboxylic acid and the glycine conjugate in their urine samples. Recovery of the initial compound in form of transformed metabolites was up to 90% within 48 h. Potentially toxic 5‐sulphoxymethylfurfural could not be found.  相似文献   

15.
Summary Domoic acid was recognized recently [1, 2] to be a marine neurotoxin associated with shellfish harvested or cultured for use as human food. Evidence about the occurrence of domoic acid and its importance to shellfish industries is reviewed. The preparation and certification of two reference materials for the determination of domoic acid, an instrument calibration solution (DACS-1, released by the Marine Analytical Chemistry Standards Program [MACSP] in May, 1989), and a tissue reference material (MUS-1, homogenized soft tissues of Mytilus edulis, released by the MACSP in August, 1989) are described. We believe these are the first certified standards or reference materials to be available for the determination of shellfish toxins, a problem of increasing importance to aquaculturists and the seafood industry, as well as to agencies concerned with the safety of food. The tissue homogenate preparation techniques we have developed and used may be of general interest for the preparation of other tissue reference materials for the determination of other organic compounds, since the sealed, fluid homogenate samples seem acceptably stable without being continuously frozen or refrigerated.NRCC No. 31925  相似文献   

16.
Rice bran arabinoxylan compound (RBAC) is derived from defatted rice bran hydrolyzed with Lentinus edodes mycelial enzyme. It has been marketed as a functional food and a nutraceutical with health-promoting properties. Some research has demonstrated this rice bran derivative to be a potent immunomodulator, which also possesses anti-inflammatory, antioxidant, and anti-angiogenic properties. To date, research on RBAC has predominantly focused on its immunomodulatory action and application as a complementary therapy for cancer. Nonetheless, the clinical applications of RBAC can extend beyond cancer therapy. This article is a narrative review of the research on the potential benefits of RBAC for cancer and other health conditions based on the available literature. RBAC research has shown it to be useful as a complementary treatment for cancer and human immunodeficiency virus infection. It can positively modulate serum glucose, lipid and protein metabolism in diabetic patients. Additionally, RBAC has been shown to ameliorate irritable bowel syndrome and protect against liver injury caused by hepatitis or nonalcoholic fatty liver disease. It can potentially ease symptoms in chronic fatigue syndrome and prevent the common cold. RBAC is safe to consume and has no known side effects at the typical dosage of 2–3 g/day. Nevertheless, further research in both basic studies and human clinical trials are required to investigate the clinical applications, mechanisms, and effects of RBAC.  相似文献   

17.
A facile strategy to construct the multifunctional rGO-DOX nanodrugs by hydrogen bonding was reported. The nanodrugs were highly loaded, pH-responsive, photothermal, and possess a favored morphology.  相似文献   

18.
重视陶瓷食具容器铅浸出量的问题   总被引:5,自引:0,他引:5  
陶瓷食具是盛放食物的容器,与人体健康休戚相关。但在陶瓷坯表面上有一层极薄的釉,制釉原料中含有铅的化合物,若在陶瓷餐具中放置果汁,醋等酸性食物,游离铅便会溶入食物中进入体内。  相似文献   

19.
20.
High energy gamma-radiation (8 to 30 MeV) is gaining acceptance for radiation therapy of patients with deep cancers. This radiation is of sufficient energy to induce photonuclear activation of the elements in the human body. Our results of measurements of nitrogen and phosphorus in an anthropomorphic phantom, a cadaver, and a cancer patient with bremsstrahlung radiation from 15 MeV electrons demonstrate the feasibility of a method to monitor these two elements in the human body in vivo by measuring the radioactivity induced in these targets by photonuclear reactions.  相似文献   

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