**3.1 Water**

Water is one such "green" solvent that can have its properties changed by changing the temperature. Water's polarity allows it to be employed as an extraction solvent

for both natural and inorganic substances that are aqueous soluble, like proteins, carbohydrates, and organic acids. Water is an important green solvent for the extraction of phytoconstituents. It has no harmful health or environmental consequences [11]. Furthermore, it is the safest and cheapest solvent. The technology used has an impact on the extractability of biologically active chemicals. Water is used as the only extractant in several ways, including decoction, infusion, and hydro distillation. Water as a solvent can be used in a variety of traditional and modern procedures. Extraction with pressurized hot water is one of the most promising new green extraction techniques and procedures, especially in a dynamic mode [11]. Water, on the other hand, has several drawbacks in terms of the less solubility of nonpolar molecules and energy required to enrich products. This difficulty can be overcome in part by employing supercritical water or a mixture of alcohol and water.

When using hydro distillation, high temperatures and long distillation times might cause volatiles to change and be lost. Supercritical water extraction (SWE) was shown to have a quicker extraction time, cheaper costs, and higher purity than hydro distillation. In terms of oxygenated components, SWE's products yielded higher valuable essential oil. To boost extraction yields, microwave-assisted extraction with water as a solvent has been proposed.
