Chitosan-based fiber-sponge materials as a promising tool for microalgae harvesting from Lake Baikal

Mass eutrophication of microalgae and cyanobacteria is observed in Lake Baikal in the past decade. In this paper, the concept of replaceable adsorption filter material based on chitosan flocculant filler and chlorinated polyvinyl chloride polymer nonwoven material are proposed. Functional and mechanical properties and morphology of the material are investigated depending on a packing density and a degree of chitosan filling. The introduction of 45% chitosan increases the Young's modulus up to 10 times, and it makes the material more rigid in 2.8 times. The high efficiency of sorption and growth inhibition of cumulative biomass culture was shown. The biomass source is taken from the coast of Barguzinsky Bay of Lake Baikal. Dominant species is microalgae of Scenedesmus genus.     

The Deubiquitinase OTUB1 Is a Key Regulator of Energy Metabolism

Dysregulated energy metabolism is a major contributor to a multitude of pathologies, including obesity and diabetes. Understanding the regulation of metabolic homeostasis is of utmost importance for the identification of therapeutic targets for the treatment of metabolically driven diseases. We previously identified the deubiquitinase OTUB1 as substrate for the cellular oxygen sensor factor-inhibiting HIF (FIH) with regulatory effects on cellular energy metabolism, but the physiological relevance of OTUB1 is unclear. Here, we report that the induced global deletion of OTUB1 in adult mice (Otub1 iKO) elevated energy expenditure, reduced age-dependent body weight gain, facilitated blood glucose clearance and lowered basal plasma insulin levels. The respiratory exchange ratio was maintained, indicating an unaltered nutrient oxidation. In addition, Otub1 deletion in cells enhanced AKT activity, leading to a larger cell size, higher ATP levels and reduced AMPK phosphorylation. AKT is an integral part of insulin-mediated signaling and Otub1 iKO mice presented with increased AKT phosphorylation following acute insulin administration combined with insulin hypersensitivity. We conclude that OTUB1 is an important regulator of metabolic homeostasis.     

Safety aspects of microbial enzyme technology,exemplified by the safety assessment of an immobilized lipase preparation,lipozyme™

The historical use of enzymes for food processing is briefly reviewed. The manufacturing process of microbial food enzymes is described including the fundamental purity criteria recommended by Joint FAO/WHO Expert Committee on Food Additives (JECFA) and Food Chemicals Codex. Principles for safety evaluation focus on the possible presence of toxic contaminants in the commercial enzyme preparation. Possible sources of any undesirable contaminants include the raw materials used, the properties of the production strain, contamination with foreign micro‐organisms, use of additives and processing aids in recovery of the enzyme. Systems for design of toxicology programmes are reviewed. A case study is given summarizing the safety evaluation of an immobilized lipase used for the interesterification of fats and oils. Based upon a no‐effect level derived from in vitro and animal feeding studies it is concluded that the enzyme is safe for the intended use.

The safety of the enzyme part of the immobilized preparation is documented by a thorough toxicology programme. The safety of the carrier, a phenol formaldehyde based ion‐exchange resin, is documented by leakage analysis of extractable materials under forced conditions, as well as by a feeding study employing a fat treated with the immobilized enzyme.     

A comparative study of the purification of betanin

Betanin is a natural pigment with antioxidant properties used as a food colourant. This work describes the spectrophotometric and chromatographic quantification of betanin (2S/15S) and its epimer isobetanin (2S/15R) in fresh beetroot juice, food-grade beetroot powder and betanin standard diluted in dextrin. Absorption spectra of all three samples were deconvoluted using a mixed three-function model. Food-grade beetroot powder has the largest amount of violet-red impurities, probably formed during processing. The purification of betanin from these complex matrices was carried out by seven different methods. Ion exchange chromatography was the most efficient method for the purification of betanin from all samples; however, fractions contain high amounts of salt. Reversed-phase HPLC as well as reversed-phase column chromatography also produced good results at a much faster rate. The longer retention time of isobetanin when compared to betanin in reversed-phase conditions has been investigated by means of quantum-mechanical methods.     

Synergistic and suppressive effects of dietary phenolic acids and other phytochemicals from cereal extracts on nuclear factor kappa B activity

In this study the combinatorial action of the main phenolic acids (ferulic, caffeic, p-coumaric and sinapic acids) found in extracts of free (ME) and bound phenolic acids (HE) from oat, barley and wheat flour on the modulation of NF-κB activity was investigated. The results show that combination of phenolic acids in low concentrations (<0.1 μg/ml) has a significant synergistic, or enhanced effect, on NF-κB activity, while their combination in high concentrations (0.3–70 μg/ml) helps to suppress the strong effect obtained by individual solutions of ferulic and p-coumaric acids. The modulation of NF-κB activity observed by HE extracts is the effect of combinatorial action of the phenolic acids present therein, while the modulation of NF-κB activity observed with ME extracts is the result of combinatorial action of phenolic acids together with other phenolic compounds present in the extracts. These results increase the knowledge about the health promoting effect from cereal consumption and dietary phenolic acids.     

Influence of copigment derived from Tasmannia pepper leaf on Davidson's plum anthocyanins

Davidson's plum (Davidsonia pruriens, F. Muell.), a native to Australian rainforests, large, crimson-red fruit, which superficially resembles plum, has been commercially cultivated in Australia since 1990s. The current production volume exceeds market demands therefore this study was designed to evaluate the suitability of Davidson's plum extract as a source of anthocyanin-based food colorant. The stability of the Davidson's plum extract towards heat treatment at 95 °C was higher than that of commercial mulberry colorant, but inferior to colorants derived from red cabbage and purple sweetpotato. An addition of a variety of phenolic acids significantly increased color intensity indicating the formation of copigmentation complexes. Commercial chlorogenic acid as well as extract from a native Australian herb rich in chlorogenic acid, Tasmannia pepper leaf (Tasmannia lanceolata, R. Br.), were both tested in model soft drink solutions subjected to light irradiation and heat treatment. In both cases, the addition of the copigment resulted in a lasting increase in color intensity. In conclusion, Davidson's plum extract can successfully be utilized as a source of natural food color. Extract from Tasmania pepper leaf can be used as a co-pigment for Davidson's plum anthocyanins. PRACTICAL APPLICATION: The color properties of an anthocyanin colorant derived from the native Australian fruit Davidson's plum are comparable to those of mulberry, which is currently applied as a food colorant in Australian food products. Utilization of Davidson's plum fruit as a source of natural color will allow the industry to increase the range of natural pigments and will create new opportunities for the emerging native food industry.     

WSA-DC——下一代高浓度高转化率WSA工艺

介绍了托普索公司新开发的WSA-DC工艺,详述其流程、优点、性能、消耗和生产数据.WSA-DC工艺是一个两次冷凝工艺,它结合了WSA工艺与两转两吸工艺的优点,通过对中间冷凝器的设计改进和仔细控制气体中的H2O/SO2比率,可以用ψ(SO2)等于或高于13%的原料气生产w(H2SO4)为99%的硫酸.以1套540t/d硫磺制酸装置为例,对WSA-DC工艺和传统干法两转两吸工艺进行了技术经济比较.     

Safety tests and antinutrient analyses of noni (Morinda citrifolia L.) leaf

BACKGROUND: Noni (Morinda citrifolia L.) leaves have a documented history of food use. However, previous safety and antinutrient studies are absent. The current investigation was conducted to assess the utility of noni leaves as food. RESULTS: No evidence of toxicity or differences in weight gain were observed in acute, subacute, and subchronic oral toxicity tests of ethanol–water (1:1 v/v) and hot‐water extracts of noni leaves in mice at doses of 2000, 200, and 20 mg kg^?1 body weight, respectively. Acute systemic anaphylaxis tests of the ethanol–water (4:1 v/v) and hot‐water extracts were negative. Further, leaf proteins were readily digested in simulated gastric fluid. Tannic acid concentrations in frozen and dried leaf were 1.6 and 25.8 g kg^?1, respectively. Phytic acid was not detected in the raw leaf (<1 g kg^?1). The average oxalic acid content was 1 g kg^?1 and was fairly uniform among 22 leaf samples from 11 islands throughout French Polynesia. Similarly, campesterol, stigmasterol, and β‐sitosterol content did not vary widely, suggesting low inter‐island content variability. CONCLUSIONS: The apparent lack of toxicity of the leaves and the hardiness of the plant make it ideal for further agricultural development, especially where sustained growth of other food crops is difficult. Copyright © 2007 Society of Chemical Industry     

Comparison of the relative recovery of polyphenolics in two fruit extracts from a model of degradation during digestion and metabolism

To simulate the effects of digestion and metabolism on the survival of different polyphenolic compounds, extracts of blueberry and apple were deglycosylated by acid hydrolysis, followed by enzymic glucuronidation under neutral conditions, yielding approximately 5% overall recovery of polyphenolics. The major polyphenolics before and after the treatment were compared, to estimate which species are likely to be present in the intestinal lumen, undegraded and available for absorption, after consumption of the fruit. Whereas blueberry extract consisted predominantly of anthocyanins, epicatechin and caffeoyl quinate esters, the major components of the treated extract were quercetin glucuronides and (unglucuronidated) caffeoyl quinates, with only traces of anthocyanidin derivatives. In apple extract, compositional changes were less marked, but caffeoyl quinates, procyanidins and quercetin were enriched at the expense of caffeic acid, epicatechin and catechin. Hydrophobic compounds like phloretin and quercetin were extensively glucuronidated, whereas caffeic acid and caffeoyl quinate were not. These results suggest that the major polyphenolic components of a fruit are not necessarily the most important contributors to any health benefits because the polyphenolic composition in the intestinal lumen and consequently, in the circulation, may be considerably different.     

Effects of Dietary Rape Seed Oil, Copper(II) Sulphate and Vitamin E on Drip Loss, Colour and Lipid Oxidation of Chilled Pork Chops Packed in Atmospheric Air or in a High Oxygen Atmosphere

The effect of addition of rapeseed oil (canola), CuSO(4) and vitamin E (all-rac-α-tocopheryl acetate) to pig diets on pork meat quality (lipid oxidation, colour and drip loss) was studied. Pigs were reared on ten different diets, either a control diet (no supplementation of rapeseed oil, CuSO(4) or vitamin E) or 6% rapeseed oil diets supplemented with CuSO(4) (0, 35 or 175mg/kg) and vitamin E (0, 100 or 200mg all-rac-α-tocopheryl acetate/kg). The natural content of vitamin E originating from feed ingredients amounted to 9-23mg vitamin E (α-tocopherol) per kg feed. Muscle vitamin E levels reflected the dietary intake and pigs fed the control diet had significantly lower levels than pigs fed rapeseed oil diets. The quality of fresh pork chops packed in air or in 80% O(2):20% CO(2) was followed during chill storage for 8 and 13 days, respectively. Colour, as measured by tristimulus colorimetry of pork chops packed in 80% oxygen atmosphere, was significantly improved with respect to redness when compared to chops packed in air, regardless of dietary treatment. The low vitamin E content in pigs fed the control feed significantly decreased a values and the oxidative stability of pork chops during chill storage compared to the other feeding groups. Packing of chops in a high-oxygen atmosphere increased lipid oxidation, especially in chops with low levels of vitamin E. Supplementation of rapeseed oil diets with 100 or 200mg vitamin E significantly decreased lipid oxidation of chill stored chops. Supplementation with CuSO(4) did not influence meat quality attributes (drip loss, colour stability and lipid oxidation) for any of the storage conditions.