NSF ANSI 321 pdf free download

NSF ANSI 321 pdf free download.Goldenseal Root (Hydrastis canadensis).
4.1.1 Macroscopic identification Goldenseal rhizome and root are traded both fresh and dried, in whole, cut, and powdered forms. When fresh, the full-grown rhizome is knotted and sub-cylindrical, 1-6.5 cm in length and 2-10 mm in diameter. Fibrous rootlets are sparsely distributed on the upper surface of the rhizome and are thicker on the sides and lower surface. The roots make up approximately 70% and the rhizomes 30% of the underground portion. On average, the rhizome and roots of a single plant weigh 5-11 g. When freshly picked, they are a bright yellow both internally and externally. When dry, the rhizome is sub-cylindrical, knotted, contorted, 1-5 cm in length, and 2-6 mm in diameter. The external surface is brownish-gray to yellowish-brown in color and rough due to the raised, circumferential growth rings which are spaced approximately 1.5-3.1 . mm apart. The upper surface has small, raised, annular scars where past stems emerged from the rhizome. These scars look like old wax seals, hence the common name. The fracture is short, brittle, clean, and resinous, revealing a smooth brownish-yellow or greenish-yellow internal surface and a yellowish-orange center. In cross section, the bark is approximately 0.5 mm thick. The wood, approximately 1 mm thick, is arranged radially with broad medullary rays. The pith is light yellowish- orange and is large in diameter compared to the wood. The dry root is 4-7 cm in length and 0.2-0.4 mm in diameter. The external surface is brownish-gray to yellowish-brown in color. The fracture is brittle and short; when magnified it has the appearance of broken beeswax. The internal surface is bright yellow to orange-yellow in younger roots, changing to greenish-yellow or dark yellowish-brown in older roots. Occasionally there is a reddish hue to the central part of the root. The bark is thick and the wood is arranged in a quadrangular fashion.4.1.3 Microscopic identification 4.1.3.1 Rhizome: Preparation in chloral hydrate: Parenchyma tissue dominates the rhizome in cross section. The rhizome has a thin, yellowish-brown cork consisting of several thin-walled cell layers. The secondary phloem consists of parenchyma cells only; these are generally thin-walled, though in the outer regions they may be somewhat thickened.’ The cells are rounded or polygonal in cross section and elongated in longitudinal view, and frequently contain yellow-brown, granular masses. Close to the cambium, semicircular regions of smaller cells indicate the sieve tubes and companion cells. Interior to the cambium and associated with the phloem bundles are found narrow cuneiform groups of vessels separated by wide medullary rays. The vessels are small with numerous slit-shaped pits, bordered pits, or helical secondary walls. Many of the pitted vessels are flled with yellow, amorphous, granular masses. The thin-walled cells of the pith, as well as other parenchyma cells, contain single or compound starch granules with either a round or slit-shaped hilum. Calcium oxalate crystals, sclereids, and fibers are absent throughout. 4.1.3.2 Root: Preparation in chloral hydrate: Parenchyma tissue dominates the root in cross section. The root is covered by a hypodermis of a single cell layer. The cortex consists of parenchyma cells only and is separated from the stele by a conspicuous primary endodermis, the cells of which often have sinuous walls. The stele shows the typical structure of an oligarch radial bundle. Sclerenchymatous cells and crystals are absent. The primary diagnostic characteristics are the pervading yellow color, the minute starch grains, the absence of calcium oxalate crystals, the nature of the elements of the wood, and the absence of sclerenchymatous cells.NSF ANSI 321 pdf download.