Biomaterial Database

Efficiency of the Polyethylene-Glycol (PEG) Embedding Medium for Plant Histochemistry. 2014

Bruno G Ferreira, and Cristiane T Teixeira, and Rosy M S Isaias

Universidade Federal de Minas Gerais (UFMG), Instituto de Ciências Biológicas, Departamento de Botânica (BGF, CTT, RMSI) Brasil.

Histochemical analyses in plants are commonly performed on hand-made sections of fresh materials. The disadvantages of embedding in historesin, paraffin or paraplast® are the alterations to cellular contents, the high costs and few evident results, depending on the test. Polyethylene-glycol (PEG), as a low cost, hydrophilic medium that maintains most of the cellular features similar to fresh conditions, may be useful for obtaining good histochemical results in thinner and homogeneous sections. The current study aimed to compare the efficiency of PEG as an embedding medium for histochemical analyses of primary and secondary metabolites accumulation. Using hand-made sections of fresh samples (T1) as a comparison, we tested the influence of the use of Karnovsky's solution as a fixative (T2) versus embedding in PEG (T3). The samples herein analyzed comprise leaves, stems, seeds and insect galls of different plant species. Neither the Karnovsky's fixative nor the embedding in PEG altered the histochemical results for starch, lipids, terpenoids, proteins and reducing sugars in T1, T2, and T3. However, PEG binds to phenols, such as tannins, flavonoids and lignins, thereby presenting false negatives in T3.

UI	MeSH Term	Description	Entries
D007915	Lepidoptera	A large order of insects comprising the butterflies and moths.
D011092	Polyethylene Glycols	Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.	Macrogols,Polyoxyethylenes,Carbowax,Macrogol,Polyethylene Glycol,Polyethylene Oxide,Polyethyleneoxide,Polyglycol,Glycol, Polyethylene,Glycols, Polyethylene,Oxide, Polyethylene,Oxides, Polyethylene,Polyethylene Oxides,Polyethyleneoxides,Polyglycols,Polyoxyethylene
D004175	Diptera	An order of the class Insecta. Wings, when present, number two and distinguish Diptera from other so-called flies, while the halteres, or reduced hindwings, separate Diptera from other insects with one pair of wings. The order includes the families Calliphoridae, Oestridae, Phoridae, SARCOPHAGIDAE, Scatophagidae, Sciaridae, SIMULIIDAE, Tabanidae, Therevidae, Trypetidae, CERATOPOGONIDAE; CHIRONOMIDAE; CULICIDAE; DROSOPHILIDAE; GLOSSINIDAE; MUSCIDAE; TEPHRITIDAE; and PSYCHODIDAE. The larval form of Diptera species are called maggots (see LARVA).	Flies, True,Flies,Dipteras,Fly,Fly, True,True Flies,True Fly
D006651	Histocytochemistry	Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.	Cytochemistry
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D016610	Tissue Embedding	The technique of placing cells or tissue in a supporting medium so that thin sections can be cut using a microtome. The medium can be paraffin wax (PARAFFIN EMBEDDING) or plastics (PLASTIC EMBEDDING) such as epoxy resins.	Embedding, Tissue
D027805	Phaseolus	A plant genus in the family FABACEAE which is the source of edible beans and the lectin PHYTOHEMAGGLUTININS.	Bean, Kidney,Bean, Tepary,Kidney Bean,Tepary Bean,Common Bean Plant,French Bean Plant,Phaseolus acutifolius,Phaseolus vulgaris,Bean Plant, Common,Bean Plant, French,Bean Plants, Common,Bean Plants, French,Beans, Kidney,Beans, Tepary,Common Bean Plants,French Bean Plants,Kidney Beans,Phaseolus vulgari,Plant, Common Bean,Plant, French Bean,Plants, Common Bean,Plants, French Bean,Tepary Beans,vulgaris, Phaseolus
D029802	Croton	A plant genus of the family EUPHORBIACEAE. The common name of dragon's blood is also used for DRACAENA and Daemonorops (ARECACEAE). CROTON TIGLIUM is the source of CROTON OIL.	Crotons
D035322	Melastomataceae	A plant family of the order Myrtales, subclass Rosidae, class Magnoliopsida composed of tropical plants with parallel-nerved leaves.	Miconia,Miconias
D064210	Secondary Metabolism	A physiochemical process which occurs in a wide range of organisms which unlike BASAL METABOLISM is not required for or essential to short-term survivability but to long-term general well-being of the organism.	Metabolism, Secondary,Metabolisms, Secondary,Secondary Metabolisms