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Extraction and Therapeutic Potential of Essential Oils: A Review
Published in Megh R. Goyal, Hafiz Ansar Rasul Suleria, Ademola Olabode Ayeleso, T. Jesse Joel, Sujogya Kumar Panda, The Therapeutic Properties of Medicinal Plants, 2019
The solvents should be non-flammable, non-toxic, and non-explosive. The solvents used in the process are ozone-friendly, and they produce no harm to the environment. Vacuum distillation is not required to release solvents, and thus the highly volatile notes are protected. As a result, the end products are like the natural ones. The energy requirements are low for the process, and it also requires very low electricity, and no fossil fuels nor wood or coal is needed. There are not any “waters” to be eliminated. The used-up plant matter can be composted or could be used as fodder for cattle.
Cipargamin: Biocatalysis in the Discovery and Development of an Antimalarial Drug
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Thomas Ruch, Elina Siirola, Radka Snajdrova
The pH drop during the course of reaction was as a result of the isopropyl amine hydrochloride (iPrNH2∙HCl), which is used as amine donor, being consumed by transaminase. This could be relatively easily fixed by continuous monitoring of pH and automatic dosage of NaOH to create optimal conditions for the transamination reaction. Together with pH monitoring it was also necessary to address the reaction equilibrium. In the initial procedure, a large excess of the amine donor (iPrNH2∙HCl) was used to achieve full conversion to the product. An alternative option was to remove the reaction byproduct, acetone, by either sparging of nitrogen gas over the reaction surface or through the reaction medium or by applying a vacuum to distil off the acetone at 50°C and approx. 120 mBar. Both of these options worked well on small to medium scale (up to 1 kg), but vacuum distillation is more advantageous in terms of further scalability. From an operational point of view, when maintaining pH and dosing base to reaction mixture under vacuum, it was necessary to identify a supplier for qualifiable pH electrodes that can withstand distillation conditions of 50°C, 120 mBar for 36 h.
Manufacture of Glycerine from Natural Fats and Oils
Published in Eric Jungermann, Norman O.V. Sonntag, Glycerine, 2018
Simple distillation is a very effective method of purification for most crude glycerine, but several factors influence both the practicality and the economics of the distillation process. The high boiling point (refer to Table 3.9) of glycerol, along with its relatively low decomposition temperature (ca. 200°C), necessitate the use of vacuum distillation systems to lower the temperature requirements. Steam is usually injected into the distillation column to lower the distillation temperatures and to minimize dehydration and polymerization of the glycerol. Water content of the crude glycerine feed must be kept low so as not to overload the vacuum system. Since some water (usually 5–10%) and stripping steam are desirable to avoid product degradation, condensers and vacuum systems must be designed to remove all water from the distilled product if a high-density (high-purity) glycerol is to be produced.
Hypoglycaemic and hypolipidemic activities of Alhagi camelorum in streptozotocin-induced diabetes in Wistar rats
Published in Archives of Physiology and Biochemistry, 2021
Fatemeh Nabiyouni, Gholamhasan Vaezi, Ali Akbar Malekirad
A. camelorum was collected around Abadeh (Fars province, Iran) and it was identified by botany group of Payamenoor University with herbarium code (002/040/073). To make the alcoholic extraction of the plant, first the aerial parts were collected and the impurities removed. Then 800 g of the plant grounded and mixed with ethyl alcohol 90% with a ratio of 1–5. The mixture kept for 24 h then placed on the shaker apparatus. Then, it was filtrated, and ethyl alcohol 70% was poured over the remained raff. This combination has been placed again on the shaker for 24 h. This extract was separated and mixed with the first extract. Next, all elimination was distilled in the vacuum distillation unit at 60 °C with 70% rotation until the left volume reduced to one-fifth of the primary volume. The tank was separated from the distiller and after passing cooling down stage; this extract was purified three times, each time with 50 cc of chloroform. The rest was poured into petri and was dried at 50 °C in an Avon (Finetech, Gyeongsangnam-do, South Korea). The yield (within 15/100 g of crushed plant) added to the normal saline to achieve various concentrations (Zarei et al.2013, Zarei et al.2015a, Zarei et al.2015b).
Relevance of animal studies in the toxicological assessment of oil and wax hydrocarbons. Solving the puzzle for a new outlook in risk assessment
Published in Critical Reviews in Toxicology, 2021
Juan-Carlos Carrillo, Dirk Danneels, Jan Woldhuis
Understanding the similarities and differences in the chemical composition between mineral oils and waxes is important for the justification of not extending the term MOSH for waxes. Both mineral waxes and oils originate from the vacuum distillation columns of the lubricating oil manufacturing unit in a petroleum refinery. After crude oil is distilled at atmospheric pressure into light fractions the resulting residue is further refined to yield a non-carcinogenic “waxy raffinate”, which is the common feedstock of mineral oils and waxes and comprises of normal, iso- and cyclo-alkanes and predominantly alkylated aromatics, as the little alkylated and naked ring 3–7 PAC have been extracted (Carrillo et al. 2019). Before it is further processed under vacuum to yield a set of oil substances (base oils and white oils), the waxy raffinate must be de-waxed. The purpose of this dewaxing is to remove long chain paraffins from the product intended to become a lubricating oil. It is at this point that waxes and oils are separated from their common “ancestor” feedstock into distinct products: slack wax and base oil. The former becomes the starting material for paraffin waxes, where the latter are lubricating base oils, which after hydrogenation/acid treatment steps become white oils. The residue of the vacuum distillation of waxy raffinate is called “bright stock” and it will be the source for a heavy lubricating oil and “bright stock slack waxes” which can be further refined to yield microcrystalline waxes which have a higher molecular weight compared to paraffin wax. These products are considered related (feedstock related) but have their own separate characteristics and chemical composition.
Assessing cancer hazards of bitumen emissions – a case study for complex petroleum substances
Published in Critical Reviews in Toxicology, 2018
Anthony J. Kriech, Ceinwen A. Schreiner, Linda V. Osborn, Anthony J. Riley
The product, bitumen, is used in many ways due to its engineering properties for building roads, waterproofing roofs and in hydraulic applications such as pond liners. Bitumen is a non-distillable residuum obtained from the distillation of suitable crude oils (Asphalt Institute, Eurobitume 2015). The distillation process normally involves atmospheric distillation followed by either vacuum distillation or steam distillation. Additional processing, such as air oxidation, solvent stripping or blending of petroleum residua of different stiffness characteristics, may be needed to form a material whose physical properties meet the technical requirements for commercial applications.