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Gellan Gum
Gellan gum is a water-soluble anionic polysaccharide produced by the bacterium '' Sphingomonas elodea'' (formerly ''Pseudomonas elodea'' based on the taxonomic classification at the time of its discovery). The gellan-producing bacterium was discovered and isolated by the former Kelco Division of Merck & Company, Inc. in 1978 from the lily plant tissue from a natural pond in Pennsylvania. It was initially identified as a substitute gelling agent at significantly lower use level to replace agar in solid culture media for the growth of various microorganisms. Its initial commercial product with the trademark as Gelrite gellan gum, was subsequently identified as a suitable agar substitute as gelling agent in various clinical bacteriological media. Chemical structure The repeating unit of the polymer is a tetrasaccharide, which consists of two residues of D-glucose and one of each residues of L-rhamnose and D-glucuronic acid. The tetrasaccharide repeat has the following structure: D-G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anionic
An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention. The net charge of an ion is not zero because its total number of electrons is unequal to its total number of protons. A cation is a positively charged ion with fewer electrons than protons while an anion is a negatively charged ion with more electrons than protons. Opposite electric charges are pulled towards one another by electrostatic force, so cations and anions attract each other and readily form ionic compounds. Ions consisting of only a single atom are termed atomic or monatomic ions, while two or more atoms form molecular ions or polyatomic ions. In the case of physical ionization in a fluid (gas or liquid), "ion pairs" are created by spontaneous molecule collisions, where each generated pair consists of a free electron an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tissue (biology)
In biology, tissue is a biological organizational level between cells and a complete organ. A tissue is an ensemble of similar cells and their extracellular matrix from the same origin that together carry out a specific function. Organs are then formed by the functional grouping together of multiple tissues. The English word "tissue" derives from the French word "tissu", the past participle of the verb tisser, "to weave". The study of tissues is known as histology or, in connection with disease, as histopathology. Xavier Bichat is considered as the "Father of Histology". Plant histology is studied in both plant anatomy and physiology. The classical tools for studying tissues are the paraffin block in which tissue is embedded and then sectioned, the histological stain, and the optical microscope. Developments in electron microscopy, immunofluorescence, and the use of frozen tissue-sections have enhanced the detail that can be observed in tissues. With these tools, the cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbitz (drink)
Orbitz was a short-lived non-carbonated fruit-flavored beverage produced by The Clearly Food & Beverage Company of Canada, makers of Clearly Canadian. It was introduced in 1997, then quickly discontinued due to poor sales. The drink was sold in five flavors, and made with small floating edible balls. Orbitz was marketed as a "texturally enhanced alternative beverage" but some consumers compared it to a potable lava lamp. The small balls floated due to their nearly equal density to the surrounding liquid, and remained suspended with the assistance of gellan gum. The gellan gum provided a support matrix and had a visual clarity approaching that of water, which increased with the addition of sugar. The gellan gum created a very weak yield stress which has been measured to be ~0.04 Pa. The product's website was bought by the Internet-based travel agency named Orbitz. Unopened bottles from the drink's original launch have become a collector's item, appearing on online auction websi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
E Number
E numbers ("E" stands for "Europe") are codes for substances used as food additives, including those found naturally in many foods such as vitamin C, for use within the European Union (EU) and European Free Trade Association (EFTA). Commonly found on food labels, their safety assessment and approval are the responsibility of the European Food Safety Authority (EFSA). The fact that an additive has an E number implies that its use was at one time permitted in products for sale in the European Single Market; some of these additives are no longer allowed today. Having a single unified list for food additives was first agreed upon in 1962 with food colouring. In 1964, the directives for preservatives were added, in 1970 antioxidants were added, in 1974 emulsifiers, stabilisers, thickeners and gelling agents were added as well. Numbering schemes The numbering scheme follows that of the International Numbering System (INS) as determined by the ''Codex Alimentarius'' committee, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stabilizer (food)
Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salting), smoke ( smoking), sugar ( crystallization), etc. This allows for longer-lasting foods such as bacon, sweets or wines. With the advent of processed foods in the second half of the twentieth century, many additives have been introduced, of both natural and artificial origin. Food additives also include substances that may be introduced to food indirectly (called "indirect additives") in the manufacturing process, through packaging, or during storage or transport. Numbering To regulate these additives and inform consumers, each additive is assigned a unique number called an " E number", which is used in Europe for all approved additives. This numbering scheme has now been adopted and extended by the '' Codex Alimentarius'' Commi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emulsifier
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms ''colloid'' and ''emulsion'' are sometimes used interchangeably, ''emulsion'' should be used when both phases, dispersed and continuous, are liquids. In an emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous phase). Examples of emulsions include vinaigrettes, homogenized milk, liquid biomolecular condensates, and some cutting fluids for metal working. Two liquids can form different types of emulsions. As an example, oil and water can form, first, an oil-in-water emulsion, in which the oil is the dispersed phase, and water is the continuous phase. Second, they can form a water-in-oil emulsion, in which water is the dispersed phase and oil is the continuous phase. Multiple emulsions are als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thickener
A thickening agent or thickener is a substance which can increase the viscosity of a liquid without substantially changing its other properties. Edible thickeners are commonly used to thicken sauces, soups, and puddings without altering their taste; thickeners are also used in paints, inks, explosives, and cosmetics. Thickeners may also improve the suspension of other ingredients or emulsions which increases the stability of the product. Thickening agents are often regulated as food additives and as cosmetics and personal hygiene product ingredients. Some thickening agents are gelling agents (gellants), forming a gel, dissolving in the liquid phase as a colloid mixture that forms a weakly cohesive internal structure. Others act as mechanical thixotropic additives with discrete particles adhering or interlocking to resist strain. Thickening agents can also be used when a medical condition such as dysphagia causes difficulty in swallowing. Thickened liquids play a vital role ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food Additive
Food additives are substances added to food to preserve Taste, flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salting), smoke (Smoking (cooking), smoking), sugar (crystallization), etc. This allows for longer-lasting foods such as bacon, Candy, sweets or wines. With the advent of processed foods in the second half of the twentieth century, many additives have been introduced, of both natural and artificial origin. Food additives also include substances that may be introduced to food indirectly (called "indirect additives") in the manufacturing process, through food packaging, packaging, or during storage or transport. Numbering To regulate these additives and inform consumers, each additive is assigned a unique number called an "E number", which is used in Europe for all approved additives. This numbering scheme has now been adopted and exte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Physiology
Plant physiology is a subdiscipline of botany concerned with the functioning, or physiology, of plants. Closely related fields include plant morphology (structure of plants), plant ecology (interactions with the environment), phytochemistry (biochemistry of plants), cell biology, genetics, biophysics and molecular biology. Fundamental processes such as photosynthesis, respiration, plant nutrition, plant hormone functions, tropisms, nastic movements, photoperiodism, photomorphogenesis, circadian rhythms, environmental stress physiology, seed germination, dormancy and stomata function and transpiration, both parts of plant water relations, are studied by plant physiologists. Aims The field of plant physiology includes the study of all the internal activities of plants—those chemical and physical processes associated with life as they occur in plants. This includes study at many levels of scale of size and time. At the smallest scale are molecular interactions of ph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytokinin
Cytokinins (CK) are a class of plant hormones that promote cell division, or cytokinesis, in plant roots and shoots. They are involved primarily in cell growth and differentiation, but also affect apical dominance, axillary bud growth, and leaf senescence. There are two types of cytokinins: adenine-type cytokinins represented by kinetin, zeatin, and 6-benzylaminopurine, and phenylurea-type cytokinins like diphenylurea and thidiazuron (TDZ). Most adenine-type cytokinins are synthesized in roots. Cambium and other actively dividing tissues also synthesize cytokinins. No phenylurea cytokinins have been found in plants. Cytokinins participate in local and long-distance signalling, with the same transport mechanism as purines and nucleosides. Typically, cytokinins are transported in the xylem. Cytokinins act in concert with auxin, another plant growth hormone. The two are complementary, having generally opposite effects. History The idea of specific substances requir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ralf Reski
Ralf Reski (born 18 November 1958 in Gelsenkirchen) is a German professor of plant biotechnology and former dean of the Faculty of Biology of the University of Freiburg. He is also affiliated to the French École supérieure de biotechnologie Strasbourg (ESBS) and Senior Fellow at the Freiburg Institute for Advanced Studies. Biography Ralf Reski studied biology, chemistry and pedagogy at the Universities of Giessen and Hamburg. He was awarded his doctorate in Genetics in 1990 by the University of Hamburg and received his habilitation in General Botany in 1994. From 1996 until 1999, he was a Heisenberg-Fellow of the German Research Foundation. He was appointed Distinguished Professor and entitled Ordinarius at the University of Freiburg in 1999, where he became Head of the newly established Department of Plant Biotechnology. From 2001 until 2011, Reski was Director Plant Biotechnology at the Centre for Applied Biosciences (ZAB, University of Freiburg). Also since 2010 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytohormone
Plant hormone (or phytohormones) are signal molecules, produced within plants, that occur in extremely low concentrations. Plant hormones control all aspects of plant growth and development, from embryogenesis, the regulation of organ size, pathogen defense, stress tolerance and through to reproductive development. Unlike in animals (in which hormone production is restricted to specialized glands) each plant cell is capable of producing hormones. Went and Thimann coined the term "phytohormone" and used it in the title of their 1937 book. Phytohormones occur across the plant kingdom, and even in algae, where they have similar functions to those seen in higher plants. Some phytohormones also occur in microorganisms, such as unicellular fungi and bacteria, however in these cases they do not play a hormonal role and can better be regarded as secondary metabolites. Characteristics The word hormone is derived from Greek, meaning ''set in motion''. Plant hormones affect gene ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
