Containers: care vegetables

When oils are used as vehicles in ophthalmic fluids, they must be of the highest purity. Vegetable oils such as olive oil, castor oil, and sesame oil have been used for extemporaneous compounding. These oils are subject to rancidity and, therefore, must be used carefully. Some commercial oils, such as peanut oil, contain stabilizers that could be irritating. The purest grade of oil, such as that used for parenteral products, would be advisable for ophthalmics. 

The extraction of vegetable plant-material requires careful selection of raw materials, in connection with chemical analysis, because the content of the vegetables to be extracted can vary substantially. Also the possibility of high concentrations of undesired substances - either contained within them, or contaminations such as pesticides - can influence the product quality enormously. Exhaustive extraction is not always possible with acceptable effort, owing to the vegetable structure, and the extraction efficiency using low-quality raw materials may be too poor to allow economic processing. 

The early statement that corruption is the mother of vegetation doubtless arose from the observation that manures, composts, dead animal bodies, and parts thereof such as blood, hair, hoofs, and so on, increased plant growth. John Woodward (cited by Russell, 1973), in a paper published in the Philosophical Transactions of the Royal Society (Vol. 21, p. 382), observed that the falloff in yields of crops grown in successive years on unmanured land could be rectified when supplied with a new fund of matter, of like sort with that it first contained which supply is made in several ways, either by the ground s being fallow some time, until the rain has poured down a fresh stock upon it or by tiller s care in manuring it. He considered that the best... 

Extracted from the bean and often called Soyabean oil. A versatile carrier suitable for all skin types. It is comparatively high, up to 17%, in unsaturated fatty acids with the unsaturated linoleic (54%), oleic (24%), palmitic (10%), linolenic (7%) and stearic (4%). It also contains the highest amount of lecithin of any vegetable oil and the cold pressed oil is particularly high in vitamin E. It needs careful storage as it oxidizes easily. Soya oil may cause allergic reactions and has been reported to damage hair. 

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