Mussels increase xenobiotic (azaspiracid) toxicity using a unique bioconversion mechanism

Azaspiracid Poisoning (AZP) is a human toxic syndrome which is associated with the consumption of bivalve shellfish. Unlike other shellfish, mussels contain a large array of azaspiracid analogs, many of which are suspected bioconversion products. These studies were conducted to elucidate the metabolic pathways of azaspiracid (AZA1) in the blue mussel (Mytilus edulis) and revealed that the main biotransformation product was the more toxic demethyl analog, AZA3. To elucidate the mechanism of this C-demethylation, an unprecedented xenobiotic bioconversion step in shellfish, AZA1 was fed to mussels that contained no detectable azaspiracids. Triple quadrupole mass spectrometry (MS) and high resolution Orbitrap MS were used to determine the uptake of AZA1 and the toxin profiles in three tissue compartments of mussels. The second most abundant bioconversion product was identified as AZA17, a carboxyl analog of AZA3, which is a key intermediate in the formation of AZA3. Also, two pairs of isomeric hydroxyl analogs, AZA4/AZA5 and AZA7/AZA8, have been confirmed as bioconversion products for the first time. Ultra high resolution (100 k) MS studies showed that the most probable structural assignment for AZA17 is 22-carboxy-AZA3 and a mechanism for its facile decarboxylation to form AZA3 has been proposed.     

Plate assay for endo-beta-N-acetylglucosaminidase activity using a chromogenic substrate synthesized by transglycosylation with Arthrobacter endo-beta-N-acetylglucosaminidase

The transglycosylation activity of Arthrobacter endo-beta-N-acetylglucosaminidase (Endo-A) was used for the enzymatic synthesis of a novel oligosaccharide, Man6GlcNAc-5-bromo-4-chloro-3-indolyl-beta-glucoside (Man6GlcNAc-Glc-beta-X). Various endo-beta-N-acetylglucosaminidases hydrolyzed this oligosaccharide, producing Man6GlcNAc and Glc-beta-X. The E. coli strains coexpressing Endo-A and beta-glucosidase formed blue colonies in the presence of Man6GlcNAc-Glc-beta-X. Therefore, endo-beta-N-acetylglucosaminidase activity could be directly detected by the plate assay. This simple plate assay is useful for screening microorganisms for endo-beta-N-acetylglucosaminidase activity.     

Inactivation of microbes using ultrasound: a review

Alternative methods for pasteurization and sterilization are gaining importance, due to increased consumer demand for new methods of food processing that have a reduced impact on nutritional content and overall food quality. Ultrasound processing or sonication is one of the alternative technologies that has shown promise in the food industry. Sonication alone is not very effective in killing bacteria in food; however, the use of ultrasound coupled with pressure and/or heat is promising. Thermosonic (heat plus sonication), manosonic (pressure plus sonication), and manothermosonic (heat and pressure plus sonication) treatments are likely the best methods to inactivate microbes, as they are more energy-efficient and effective in killing microorganisms. Ultrasonic processing is still in its infancy and requires a great deal of future research in order to develop the technology on an industrial scale, and to more fully elucidate the effect of ultrasound on the properties of foods.     

Involvement of copper in microsomal mixed-function oxidase reactions: a review.

Microsomes from various mammalian tissues contain the components of a short, non-phosphorylating electron transport chain which is an obligatory requirement for numerous mixed function oxidase reactions. Certain of these reactions, in particular Δ9-desaturation of fatty acids and the hydroxylation of drugs, are influenced by dietary copper deficiency. The inhibition of Δ9-desaturase activity by copper chelating agents and the reactivation by copper ions suggest that copper may be involved catalytically in the reaction. Copper also influences Δ6-desaturation of fatty acids, and the synthesis of prostaglandins. Copper-proteins are ideally suited as terminal components of electron transport chains and as such may function in a greater variety of mixed-function oxidase reactions than has hitherto been considered.     

High pressure-temperature effects on enzymatic activity: Naringin bioconversion

Initially exploited in chemistry and physics, high-pressure technology has gained importance in various fields.     

Determination of aminoglycosides and quinolones in food using tandem mass spectrometry: a review

The widespread use of antibiotics in dairy cattle management may result in the presence of antibiotic residues in food. While rapid screening tests are commonly used to detect the presence of antibiotics in food, more accurate chromatographic-mass spectrometric methods combined with tandem mass spectrometry (MS/MS) are required to determine the identity and quantity of the antibiotic present. These methods (HPLC/MS/MS) may have the greatest potential for accomplishing direct multi-residue identifications in complex biological matrices, such as food. This study reviews recent applications of tandem mass spectrometry in the determination of antibiotic residues, such as aminoglycosides and quinolones in food.     

Microencapsulation using starch as wall material: A review

Microencapsulation is a process oriented to protect substances that are susceptible to decomposition or reduction in their functionality due to different degradation reactions (i.e., oxidation, hydrolysis, etc.). Diverse wall materials, including some carbohydrates, preserve substances against adverse temperature, pH, humidity, oxygen, and other components that can react with the protected material. Starch is a wall material that is widely used for microencapsulation purpose. Unmodified and modified starches are increasingly considered for microencapsulation of vitamins, essential oils, flavors, drugs, and microorganisms. Recently, spherical aggregates of starch using small granules (1–3 μm) were developed for encapsulation purposes. Spherical aggregates are produced when small starch granules in the presence of additional bonding agents (e.g., proteins and hydrocolloids) are spray dried. Some studies have reported the application of spherical aggregates, but they neither report the effects of amylose content nor the molecular weight of amylopectin. In this sense, this review focuses on the state of the art of starch spherical aggregates and the perspectives of their applications as encapsulating agents.     

Wood-cement composites: a review

This paper reviews the research reported mostly in the last 10 years in the most common journals on the wood-cement composites field. The focused topics include: the problem of the compatibility (or not) between cement and woods, what causes it, ways of overcoming the problem; methods for manufacture and the properties exhibited by common wood-composites; special techniques to accelerate the curing of cement and to improve the properties of wood-cement composites; manufacture of nonwood vegetable raw materials-cement composites; durability against weathering and fungi; and construction materials. A discussion on the state-of-the-art is also presented.     

Basmati rice: a review

India contributes about one-third of the world acreage under rice. Rice is available in over 5000 varieties, of which Basmati rice occupies a prime position on account of its extra long superfine slender grains, pleasant, exquisite aroma, fine cooking quality, sweet taste, soft texture, length-wise elongation with least breadth-wise swelling on cooking and tenderness of cooked rice. This article reviews the quality and aroma traits of Basmati rice, particularly the varieties grown in different parts of India and Pakistan, the agronomy, breeding and physiology of the grain, the trade scenario, Agmark grade designation for export and the US patent of new hybrid strains of Basmati.     

In situ observation of CO2 sequestration reactions using a novel microreaction system

A novel, externally controlled microreaction system has been developed to provide the first in situ observations of the reaction processes that control CO2 sequestration via mineral carbonation. The system offers pressure (to 20 MPa), temperature (to 250 degrees C), and activity control suitable for investigating a variety of fluid-fluid and fluid-solid interactions of environmental interest. Mineral sequestration efforts to date have effectively accelerated carbonation, a natural mineral weathering process, to an industrial timescale. However, the associated reaction mechanisms are poorly understood, limiting further process development. Synchrotron X-ray diffraction and Raman spectroscopy have been used to provide the first in situ insight into the associated supercritical mineral carbonation process. Magnesite was found to form directly under the reaction conditions observed (e.g., 150 degrees C and 15 MPa CO2),facilitating geologically stable sequestration. Thermodynamic analysis of fluid-phase species concentrations in the Na+ buffered H2O-CO2 reaction system found the primary aqueous reactant species to be CO2(aq) and HCO3-, with CO2(aq) more prevalent under the reaction conditions observed. The microreactor provides a powerful new tool for in situ investigation of a broad range of environmentally, fundamentally, and commercially important processes, including the reactions associated with geological carbon dioxide sequestration.     

Production of a new pyridine N-oxide by bioconversion with Cunninghamella echinulata var. elegans

A new N-oxide was produced from 3-(N-Boc-aminomethyl)-5-bromopyridine by bioconversion with Cunninghamella echinulata var. elegans ATCC 9245, and its structure was established based on the spectral data. The microbial N-oxidation is efficient and highly selective. The substrate was transformed into the product in 7 days.     

Simple and selective analysis of different antibiotics in milk using molecularly imprinted polymers: a review

ABSTRACT

The frequent, sometimes illegal, use of antibiotics for therapeutic and prophylactic purposes in dairy cattle management may cause residues in milk. Because of problems concerning bacterial resistance or allergies in consumers, monitoring of residues is required. In spite of the huge development of analytical instrumentation during recent years, sample preparation is still a bottleneck of the analytical process. In this regard, efforts have been directed towards improving selectivity during extraction and clean-up of samples. Compared to traditional sorbents, molecularly imprinted polymers (MIPs) are excellent materials to provide selectivity for sample pretreatment. This review presents the application of MIPs as effective sorbents for separation, clean-up, pre-concentration and analysis of different antibiotics in milk.     

Biopolymer-based antimicrobial packaging: a review

The term antimicrobialpackaging encompasses any packaging technique(s) used to control microbial growth in a food product. These include packaging materials and edible films and coatings that contain antimicrobial agents and also techniques that modify the atmosphere within the package. In recent years, antimicrobial packaging has attracted much attention from the food industry because of the increase in consumer demand for minimally processed, preservative-free products. Reflecting this demand, the preservative agents must be applied to packaging in such away that only low levels of preservatives come into contact with the food. The film or coating technique is considered to be more effective, although more complicated to apply. New antimicrobial packaging materials are continually being developed. Many of them exploit natural agents to control common food-borne microorganisms. Current trends suggest that, in due course, packaging will generally incorporate antimicrobial agents, and the sealing systems will continue to improve. The focus of packaging in the past has been on the appearance, size, and integrity of the package. A greater emphasis on safety features associated with the addition of antimicrobial agents is perhaps the next area for development in packaging technology.     

Photoinitiators: a food safety review

Ultraviolet light printing inks are considered safer than the classical inks; however, despite being on the outer surface of the packaging material, their components can migrate into foodstuffs and can give rise to contamination. Photoinitiators are a part of the formulation of printing inks, being an important class of migrant, for which there have been more than 100 incidents of contamination of packaged food with photoinitiators reported through Rapid Alert System for Food and Feed (RASFF) alerts in the European Union. In this review the process of photo-polymerisation is explained in depth to provide an insight into the complexity of the process, and the diversity of potential contaminants together with their degradation products. The critical factors affecting the migration process itself are reviewed, together with analytical methods and the current legislation in the European Union and other parts of the world.     

Cherries and health: a review

Cherries, and in particular sweet cherries, are a nutritionally dense food rich in anthocyanins, quercetin, hydroxycinnamates, potassium, fiber, vitamin C, carotenoids, and melatonin. UV concentration, degree of ripeness, postharvest storage conditions, and processing, each can significantly alter the amounts of nutrients and bioactive components. These constituent nutrients and bioactive food components support the potential preventive health benefits of cherry intake in relation to cancer, cardiovascular disease, diabetes, inflammatory diseases, and Alzheimer's disease. Mechanistically, cherries exhibit relatively high antioxidant activity, low glycemic response, COX 1 and 2 enzyme inhibition, and other anti-carcinogenic effects in vitro and in animal experiments. Well-designed cherry feeding studies are needed to further substantiate any health benefits in humans.     

巧克力油脂相容性研究进展

通过比较和分析可可脂、类可可脂、月桂酸型代可可脂、非月桂酸型代可可脂、乳脂、坚果油等巧克力用油的二元、三元等固相图,并结合其脂肪酸组成、甘三酯组成、晶体类型、结晶特性等,总结了巧克力用油的相容性,并探讨了可能引起相容性差异的原因,对巧克力用油相容性的评判给出了指导性建议.     

Personal cooling garments: a review

Personal cooling garments have been developed to reduce the risk of heat stress and heat-related injuries in hot environments. The human body can suffer from a kind of heat stress resulting in reduced working endurance and performance and an increased risk of heat illness when exposed to hot climates. This gets worse when combined with physical work, such as firefighting, military drills, special work situations, and sports. The use of protective clothing which limits the sweat evaporation of the body can also make the situation worse. This review includes a brief look at the human thermoregulation and its relation with the cooling garments, classification of the personal cooling garments, testing procedures, and parameters affecting the efficiency of the cooling garments.     

Topically applied KTTKS: a review

Skin ageing is an irreversible process that is caused by both intrinsic and extrinsic factors. The possibility of arresting or delaying skin ageing represents a large research area and has a big potential in the cosmetics sector. Recently, the polypeptide lysine-threonine-threonine-lysine-serine (KTTKS) has attracted a lot of attention and it features in numerous up-market cosmetic products where it has become erroneously associated with the term 'pentapeptide'. In this study, we review in detail KTTKS and its major derivatives, in terms of the limited information in the literature and an appraisal of its physicochemical and theoretical skin permeation properties. There appears to be a sound in vitro basis for its action on fibroblasts due to its stimulatory effect on extracellular matrix synthesis, where the stimulatory effect of KTTKS is specific to collagen types I and III and fibronectin expression. However, there is a surprising absence of in vitro skin penetration data in the literature, and there are relatively few clinical studies using these materials.     

Invited review: Environmental impacts of dairy processing and products: a review

The objective of this review is to summarize research efforts and case studies to date of the environmental impacts from dairy processing. The pervasiveness of greenhouse gas emission, water use, consumer waste, and other environmental impacts of dairy are described. An outline of the method of choice, the life cycle assessment, for conducting research and deciding appropriate allocation of the impacts is provided. Specific research examples in dairy processing highlight how the representative final product is associated with environmental impacts to air, water, and land. The primary conclusion from the study was the usefulness of life cycle assessment methodology and the need for further research due to limited studies, variable data, and the magnitude of environmental impact.