蓝莓多酚的提取及功效的研究进展

多酚具有多重功效,逐渐引起了人们的重视。按照多酚的结合方式可分为可萃取多酚（EPP）和不可萃取多酚（NEPP）,本文从提取、功效两个方面综述了国内外对蓝莓中EPP和NEPP的研究概况。     

Intake and bioaccessibility of total polyphenols in a whole diet

The knowledge of dietary intake of polyphenols and their bioaccessibility in the human gut are key factors in assessing their significance in human health. The aim of this work was to estimate the amount of total polyphenols consumed in a whole diet (Spanish Mediterranean diet) and their intestinal bioaccessibility. Total polyphenols were determined, as the sum of the polyphenols present in methanol:acetone:water extracts (extractable polyphenols) of plant foods and condensed tannins and hydrolysable polyphenols (non-extractable polyphenols) in the corresponding residues. The polyphenols intestinal bioaccessibility was estimated by an in vitro gastrointestinal model where food polyphenols are released by enzyme digestion and colonic fermentation. The mean daily intake of polyphenols in the Spanish diet was estimated between 2590 and 3016 mg/person/day. The amount of non-extractable polyphenols was almost double that of extractable polyphenols. It was estimated that about 48% of dietary polyphenols are bioaccessible in the small intestine, while 42% become bioaccessible in the large intestine.     

Antioxidant and antiproliferation effects of extractable and nonextractable polyphenols isolated from apple waste using different extraction methods

Fruits and vegetables waste byproducts could be utilized as a good source of cheap antioxidants for improving human health and reducing the risks of some chronic diseases. Results from examining industrial apple waste revealed that the total polyphenolic content in nonextractable polyphenols (NEPPs) reached 539.84 ± 8.90 mg as gallic acid equivalents/1 g of dry wt. in comparison to 77.26 ± 11.53 mg dry wt. of extractable polyphenols (EPPs). The antioxidant activities of NEPPs reported as percentage reduction in 2,2-Diphenyl-1-picrylhydrazyl and 2'.2'-azinobis(3-ethylbenzothiazline-6-sulfonic acid) diammonium salt were 89.76 ± 0.93% and 99.78 ± 0.38%, respectively. In addition, the antiproliferation study on human HeLa, HepG2, and HT-29 cancer cells showed that NEPPs at the concentration of 1 mg/mL had significant inhibitory effects against all tested cancer cells (46.2% to 95%), where EPP showed lower effect (3.9% to 22.2%). These results clearly indicated that NEPPs from industrial apple waste could be a good source of natural antioxidants with significant antiproliferation efficacy against human cancer cells.     

蓝莓多酚对巨噬细胞中iNOS、COX-2基因表达的影响

RAW264.7巨噬细胞被脂多糖预刺激后,添加从蓝莓中分离制备的不同质量浓度的可萃取多酚（extractablepolyphenols,EPP）和不可萃取多酚（non-extractable polyphenols,NEPP）,培养不同的时间,研究不同质量浓度及培养时间对诱导型一氧化氮合酶（inducible nitric oxide synthase,iNOS）、环氧合酶（cyclooxygenase-2,COX-2）基因相对表达量的影响。结果表明：从蓝莓中分离的EPP和NEPP均能抑制iNOS、COX-2基因表达,在12 h培养时间内,2 种多酚的抑制效果较好,且EPP的抑制效果明显好于NEPP。这证明蓝莓中的NEPP同EPP一样,可通过抑制iNOS、COX-2 mRNA的表达表现出明显的抗炎活性。     

The contribution of fruits and vegetables to dietary intake of polyphenols and antioxidant capacity in a Mexican rural diet: Importance of fruit and vegetable variety

There is mounting evidence of the health-protective role of the consumption of fruits and vegetables, which are the major contributors to dietary polyphenol intake. Lack of knowledge about the consumption of phytochemicals in the Mexican diet makes it difficult to evaluate their health significance. The aim of this study was therefore to estimate the contribution of fruit and vegetable consumption to dietary polyphenol intake and dietary antioxidant capacity in a rural population in Mexico. Despite a low intake of fruits and vegetables (< 400 g/day) in the Mexican rural diet, the mean daily intake of dietary polyphenols (> 800 mg/day) and dietary antioxidant capacity (1000-2000 ??mol trolox equivalents/day) from fruits and vegetables was similar to those determined in the Spanish Mediterranean diet. Local fruits and vegetables consumed in the Mexican rural diet are rich in polyphenols with antioxidant properties and are important source of bioactive compounds and dietary fibers. Fruit and vegetable intake needs to be promoted and lifestyle and environmental factors enhanced to improve the health status of obese Mexican rural populations.     

Macromolecular antioxidants or non-extractable polyphenols in fruit and vegetables: Intake in four European countries

Macromolecular antioxidants or non-extractable polyphenols are an emerging and ignored fraction of dietary antioxidants that present differential structural and physiological features as compared with the well-known extractable polyphenols. In this study, the macromolecular antioxidant content and profile were determined by the first time for the 24 most consumed fruit and vegetables in four European countries (France, Germany, The Netherlands and Spain). Results showed that macromolecular antioxidants, made up of hydolysable polyphenols and polymeric proanthocyanidins, are major contributors (mean value 57%) to the total polyphenol content of fruit and vegetables. Macromolecular antioxidant intake from fruit and vegetable determined in the four countries selected was about 200 mg. Spain had the highest daily per capita macromolecular antioxidant intake from fruit, while The Netherlands had the highest intake derived from vegetables. Future studies of plant food macromolecular antioxidant analysis and of dietary intakes in different populations are needed to elucidate the contribution of these macromolecular antioxidants to the health effects associated with fruit and vegetable consumption, and with dietary antioxidant intake.     

Definition of the Mediterranean diet based on bioactive compounds

Antioxidant (polyphenols and carotenoids) and nonantioxidant (phytosterols) bioactive compounds and dietary fiber may have a significant role in health. The intake of these compounds is strongly linked with the high consumption of fruits, vegetables, and unrefined cereals. A whole-diet approach to these food constituents is intended to render the current definition of Mediterranean diet based on food consumption more comprehensive. The Mediterranean dietary pattern can be characterized by the following four essential dietary indicators: 1) Monounsaturated to saturated fatty acid ratio (range: 1.6 to 2.0); 2) Intake of dietary fiber (41 to 62 g/person/day); 3) Antioxidant capacity of the whole diet (3500 to 5300 trolox equivalent/person/day); 4) Phytosterols intake (370 to 555 mg/person/day). The contribution of foods and beverages to these parameters is described. Spanish National Food Consumption Data for the years 2000 and 1964 were used to quantify the lowest and highest range values. The occurrence of these indicators in the Mediterranean diet has specific characteristics and there is sufficient scientific evidence to support the beneficial health effects.     

Dietary polyphenols and the prevention of diseases

Polyphenols are the most abundant antioxidants in the diet and are widespread constituents of fruits, vegetables, cereals, dry legumes, chocolate, and beverages, such as tea, coffee, or wine. Experimental studies on animals or cultured human cell lines support a role of polyphenols in the prevention of cardiovascular diseases, cancers, neurodegenerative diseases, diabetes, or osteoporosis. However, it is very difficult to predict from these results the effects of polyphenol intake on disease prevention in humans. One of the reasons is that these studies have often been conducted at doses or concentrations far beyond those documented in humans. The few clinical studies on biomarkers of oxidative stress, cardiovascular disease risk factors, and tumor or bone resorption biomarkers have often led to contradictory results. Epidemiological studies have repeatedly shown an inverse association between the risk of myocardial infarction and the consumption of tea and wine or the intake level of some particular flavonoids, but no clear associations have been found between cancer risk and polyphenol consumption. More human studies are needed to provide clear evidence of their health protective effects and to better evaluate the risks possibly resulting from too high a polyphenol consumption.     

The role of dietary polyphenols in the moderation of the inflammatory response in early stage colorectal cancer

Current focus in colorectal cancer (CRC) management is on reducing overall mortality by increasing the number of early-stage cancers diagnosed and treated with curative intent. Despite the success of screening programs in down-staging CRC, interval cancer rates are substantial and other strategies are desirable. Sporadic CRC is largely associated with lifestyle factors including diet. Polyphenols are phytochemicals ingested as part of a normal diet, which are abundant in plant foods including fruits/berries and vegetables. These may exert their anti-carcinogenic effects via the modulation of inflammatory pathways. Key signal transduction pathways are fundamental to the association of inflammation and disease progression including those mediated by NF-κB and STAT, PI3K and COX. Our aim was to examine the evidence for the effect of dietary polyphenols intake on tumor and host inflammatory responses to determine if polyphenols may be effective as part of a dietary intervention. There is good epidemiological evidence of a reduction in CRC risk from case-control and cohort studies assessing polyphenol intake. It would be premature to suggest a major public health intervention to promote their consumption; however, dietary change is safe and feasible, emphasizing the need for further investigation of polyphenols and CRC risk.     

Antioxidant and functional properties of a high dietary fibre powder from carambola (Averrhoa carambola L.) pomace

The use of carambola pomace as a raw material for the production of a high dietary fibre powder (HDFP) was investigated. A face‐centred design was used to study the effects of extraction conditions, namely water‐to‐pomace ratio, time and temperature, on both reducing sugars (RS) and total extractable polyphenols (EPP) contents of fibre concentrate. RS content decreased by increasing extraction times and water‐to‐pomace ratios, while EPP tend to diminish by increasing temperature and contact time (P < 0.01). Selected HDFPs showed an EPP content in the range of 5.0–6.1 g GAE 100 g^?1 dry basis (db), with antioxidant activities between 386.2–443.9 and 204.7–228.6 μmol Trolox equivalents g^?1 db according to FRAP and ABTS assays, respectively. HDFP obtained at 55 °C, 5 min and 2:1 water‐to‐pomace ratio exhibited the highest EPP content, total dietary fibre (84.0% db) and dietary indigestible fraction (61.3% db). This product can be considered as a potential valuable food ingredient considering their oil retention and swelling capacities.     

Antioxidant capacity of the Spanish Mediterranean diet

The objective of this work was to determine the total dietary antioxidant capacity (TDAC) of the Spanish Mediterranean diet. The antioxidant capacity of plant foods and beverages included in National food consumption data was determined. TDAC of the Spanish diet was estimated at 6014 and 3549 μmol trolox equivalents by FRAP (ferric reducing antioxidant power) and ABTS (free radical-scavenging capacity) procedures, respectively. About 68% of TDAC came from beverages and 20% from fruits and vegetables, with a very low contribution from cereals. The capacity to inhibit in vitro LDL oxidation of plant foods and beverages was consistent with their antioxidant capacity. The recommended daily intakes of antioxidant vitamins, C and E, represent about 10% of TDAC. Total phenolics intake was estimated as 1171 mg gallic acid/person/day by the Folin–Ciocalteau method. TDAC may be a parameter to be considered in nutritional and epidemiological studies.     

Dietary intake of pesticide residues: cadmium, mercury, and lead.

Information on the dietary intake of chemical contaminants has been obtained from institutions participating in GEMS/Food. Contaminants studied include certain organochlorine and organophosphorous pesticides, PCBs, cadmium, mercury, and lead. The intakes are compared with toxicologically acceptable intake levels established by international expert groups. In most cases, dietary intakes of organochlorine and organophosphorous pesticides are well below the Acceptable Daily Intake (ADI) of the respective pesticide. Of some 21 countries providing information on the average dietary intake of cadmium, only in one case is the Provisional Tolerable Weekly Intake (PTWI) exceeded. Several countries identified cereals and cereal products and root and tuber vegetables as the main contributors to the dietary intake of cadmium. For mercury, all reported intakes are below the PTWI of methylmercury. The contribution of fish to the total intake of mercury varied from 20% to 85%, depending on the country. Therefore, the general assumption that fish is the main contributor to the total dietary intake of mercury may, at times, not be justified. Average dietary intake of lead exceeding or approaching the PTWI are reported for adults and infants and children in some countries. Foodstuffs which contribute most to the intake of lead vary from country to country, and have been identified as being alternately drinking water, beverages, cereals, vegetables and fruit.     

Nickel in foods and the diet

Food has been found to be the main source of nickel intake by man. Nickel was fairly evenly distributed throughout the various food groups examined but highest concentrations of nickel were found in the canned vegetables, sugars and preserves, and bread and cereals food groups, suggesting a contribution from food processing equipment and, possibly, food cans. Mean dietary nickel intakes in the UK (1981-4) were between 0.14 and 0.15 mg/day. The contribution made to dietary nickel intakes by nickel from food utensils and cookware is discussed.     

几类不同食物对肠道菌群调节作用的研究进展

肠道菌群是机体的重要组成部分,肠道菌群能在一定程度上影响宿主的营养代谢和健康。肠道菌群的组成与功能受宿主生理状态、遗传、饮食习惯、年龄和环境等多重因素的影响。其中,膳食是影响肠道菌群结构和功能最为重要且较为迅速的因素。作为日常生活中常见的食物资源,杂粮、杂豆和果蔬等食物含有的膳食纤维和多酚等物质已经被证明具有调节肠道菌群的作用。肠道菌群能够发酵膳食纤维,代谢后释放维生素以及短链脂肪酸等代谢产物,并选择性地促进一些肠道有益菌的增殖,进而在一定程度上促进宿主健康。此外,大部分酚类物质也在肠道中被肠道菌群代谢分解后进一步提高酚类物质的生物利用率,从而改善宿主生理状态。本文围绕日常生活中常见的食物资源如杂粮杂豆以及水果蔬菜等对肠道菌群的调节作用进行综述,展望以肠道菌群为靶点的代谢性疾病预防与治疗或膳食干预的前景。     

果蔬中总多酚和维生素C测定方法优化的研究

目的建立一种简单、准确地测定果蔬中总多酚和维生素C含量的方法。方法采用Oasis HLB固相萃取柱富集待测物质,用纯水洗脱回收水溶性干扰物质,用甲醇洗脱回收多酚类物质,加热水洗脱液除去其中的维生素C,优化福林酚比色法,测定总多酚和维生素C的含量。结果该方法的线性方程为Y=0.0118X+0.0045,R2=0.9989,确定福林酚比色法的条件为:在760 nm处测定,福林酚试剂:水(1:1),7.5%的Na2CO3溶液,温度为20~30℃,静置60 min。通过采用福林酚比色法分别测定原料提取液(RE)和水洗脱液(WE)中还原性物质的含量,取其差值作为样品总多酚含量。同时,测定加热处理水洗脱液(HWE)中还原性物质的含量,取其与WE测定结果的差值作为样品维生素C的含量。结论此方法简便实用、条件易满足,分析结果可靠,可应用于果蔬总多酚和维生素C含量的测定。     

Assessment of dietary intake of polychlorinated biphenyls from a total diet study conducted in Pavia, Northern Italy

The diet is considered to be the main source of body burden of polychlorobiphenyls (PCBs) in the general population. The most cost-effective and reliable way to estimate the dietary intake is based on total diet studies (TDSs). The aim of the present study was to provide a reliable estimate of recent average dietary intakes of PCBs in Northern Italy. Congener-specific analysis of PCBs was undertaken on total diet samples collected at the cafeteria of the University of Pavia. The average daily intake for total PCBs was calculated to be 0.26 µg/person day^-1. The major contributor to PCB intake was accounted for by pooled samples of bread, cereals and potatoes, followed by the protein composite, and fruit and vegetables. Although diverse dietary habits and differences in sampling and analytical procedures make comparison between different studies difficult, the daily intake of PCBs in Northern Italy can be located in the lower part of the range for values reported in the literature.     

Macromolecular Antioxidants and Dietary Fiber in Edible Seaweeds

Seaweeds are rich in different bioactive compounds with potential uses in drugs, cosmetics and the food industry. The objective of this study was to analyze macromolecular antioxidants or nonextractable polyphenols, in several edible seaweed species collected in Chile (Gracilaria chilensis, Callophyllis concepcionensis, Macrocystis pyrifera, Scytosyphon lomentaria, Ulva sp. and Enteromorpha compressa), including their 1st HPLC characterization. Macromolecular antioxidants are commonly ignored in studies of bioactive compounds. They are associated with insoluble dietary fiber and exhibit significant biological activity, with specific features that are different from those of both dietary fiber and extractable polyphenols. We also evaluated extractable polyphenols and dietary fiber, given their relationship with macromolecular antioxidants. Our results show that macromolecular antioxidants are a major polyphenol fraction (averaging 42% to total polyphenol content), with hydroxycinnamic acids, hydroxybenzoic acids and flavonols being the main constituents. This fraction also showed remarkable antioxidant capacity, as determined by 2 complementary assays. The dietary fiber content was over 50% of dry weight, with some samples exhibiting the target proportionality between soluble and insoluble dietary fiber for adequate nutrition. Overall, our data show that seaweed could be an important source of commonly ignored macromolecular antioxidants.     

State of Polyphenols in the Drying Process of Fruits and Vegetables

This review presents an overview of drying technologies and its impact on the polyphenol content of vegetables and fruits. Polyphenols contribute to many health benefits and can act as antioxidants. Specifically an increased intake of polyphenols has been shown to decrease the incidence of cardiovascular disease; furthermore, it has been shown to help reduce the risk of neurodegenerative diseases in humans. Many researchers have reported on the effect of different drying techniques on the polyphenol content in fruits and vegetables. Polyphenol degradation mechanisms proposed in literature and pretreatments that potentially lead to higher retention of polyphenols during drying are also discussed.     

An analysis of the etiology of anemia and iron deficiency in young women of low socioeconomic status in Bangalore, India

BACKGROUND: Anemia and iron deficiency are significant public health problems in India, particularly among women and children. Recent figures suggest that nearly 50% of young Indian women are anemic. OBJECTIVES: Few studies have comprehensively assessed etiologic factors contributing to anemia and iron deficiency in India. Hence, this study assessed the relative importance of various factors contributing to these problems in young women of low socioeconomic status in Bangalore, India. METHODS: A random sample of 100 nonpregnant, nonlactating women 18 to 35 years of age, selected from among 511 women living in a poor urban settlement, participated in this study. Data were obtained on demography, socioeconomic status, anthropometry, three-day dietary intake, blood hemoglobin, hemoglobinopathies, serum ferritin, serum C-reactive protein, and stool parasites. RESULTS: The prevalence rates of anemia and iron deficiency were 39% and 62%, respectively; 95% of the anemic women were iron deficient. The mean dietary iron intake was 9.5 mg per day, predominantly from the consumption of cereals, pulses, and vegetables (77%). The estimated bioavailability of nonheme iron in this diet was 2.8%. Dietary intakes were suboptimal for several nutrients. Blood hemoglobin was significantly correlated with dietary intake of fat, riboflavin, milk and yogurt, and coffee. Serum ferritin was significantly correlated with intake of niacin, vitamin B12, and selenium. Parasitic infestation was low. CONCLUSIONS: An inadequate intake of dietary iron, its poor bioavailability, and concurrent inadequate intake of dietary micronutrients appear to be the primary factors responsible for the high prevalence of anemia and iron deficiency in this population.     

Polychlorinated naphthalenes in foods: estimated dietary intake by the population of Catalonia,Spain

Concentrations of polychlorinated naphthalenes (PCNs) were measured in foodstuffs randomly acquired in seven cities of Catalonia, Spain. A total of 108 samples, belonging to 11 food groups (vegetables, tubers, fruits, cereals, pulses, fish and shellfish, meat and meat products, eggs, milk, dairy products, and oils and fats), were analyzed by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). The levels of tetra-, penta-, hexa-, and hepta-CNs, those of octachloronaphthalene, and the mean sum concentration of tetra-octa-CN were determined. The highest concentration of total PCNs was found in oils and fats (447 pg/g), followed by cereals (71 pg/g), fish and shellfish (39 pg/g), and dairy products (36 pg/g). In general, tetra-CN was the predominant homologue in all food groups except for fruits and pulses, which had greater proportions of hexa-CNs. The dietary intake of total PCNs was subsequently determined. For calculations, recent data on consumption of the selected food items were used. Intake of PCNs was estimated for five population groups of Catalonia: children, adolescents, male and female adults, and seniors. When the dietary intake of total PCNs was expressed in nanogram per kilogram of body weight per day, it was age-dependent, with the highest and lowest values corresponding to children (1.65) and seniors (0.54), respectively. The largest contribution to the daily PCNs intake came from oils and fats and from cereals. The result of the current study is the first published report concerning human exposure to PCNs through the diet.