Modern Methods of Pre-Treatment of Plant Material for the Extraction of Bioactive Compounds

Abstract

In this review, recent advances in the methods of pre-treatment of plant material for the extraction of secondary metabolites with high biological activity are presented. The correct preparation of the material for extraction is as important as the selection of the extraction method. This step should prevent the degradation of bioactive compounds as well as the development of fungi and bacteria. Currently, the methods of preparation are expected to modify the particles of the plant material in such a way that will contribute to the release of bioactive compounds loosely bonded to cell wall polymers. This review presents a wide range of methods of preparing plant material, including drying, freeze-drying, convection drying, microwave vacuum drying, enzymatic processes, and fermentation. The influence of the particular methods on the structure of plant material particles, the level of preserved bioactive compounds, and the possibility of their release during the extraction were highlighted. The plant material pre-treatment techniques used were discussed with respect to the amount of compounds released during extraction as well their application in various industries interested in products with a high content of biologically active compounds, such as the pharmaceutical, cosmetics, and food industries.

Methods of Isolation of Active Substances from Garlic (Allium sativum L.) and Its Impact on the Composition and Biological Properties of Garlic Extracts

“…It has been shown in the literature that, in the case of both fruit and vegetables, the extraction method and the type of solvent affect the content of bioactive ingredients and biological properties [ 9 , 10 , 11 , 12 ]. Bioactive compounds isolated from plants, including garlic, are especially used in the pharmaceutical, food, and cosmetic industries [ 13 ]. Factors that influence the isolation and extraction efficiency include weighing, volume measurement, mixing, dilution, heating, cooling, fractionation, purification, and preservation [ 13 ].…”

“…Bioactive compounds isolated from plants, including garlic, are especially used in the pharmaceutical, food, and cosmetic industries [ 13 ]. Factors that influence the isolation and extraction efficiency include weighing, volume measurement, mixing, dilution, heating, cooling, fractionation, purification, and preservation [ 13 ]. Each solvent used in the extraction of active compounds is characterized by different polarities, which may be important in terms of the solubility of bioactive compounds and, consequently, the extraction efficiency [ 14 , 15 ].…”

“…Moreover, the volume ratio of individual solvents (in extractions with solvent mixtures) is also important and may correlate with the amount of recovery of individual bioactive compounds [ 15 ]. For this reason, the choice of the extraction method should be based on the following factors: the nature of the plant material, the nature of isolated compounds, the impact of the extraction method on the degradation of compounds, and the development of undesirable microorganisms [ 13 ]. Moreover, the method of isolation of active ingredients should be safe for consumers and acceptable for human consumption, e.g., as a food additive.…”

Antioxidant activity of herbal formulation containing Tinosporia cordifolia, Moringa oleifera and Allium sativum

“…In this method, freshly collected plant material (M. oleifera, T. cordifolia, and A. sativum) chopped, shade dried and grounded separately for each plant sample. Through, the dried coarse plant material, different extracts prepared for each plant sample individually (Krakowska-Sieprawska et al, 2022).…”

“…Finally, the extracts weighed, and their percentage yield was evaluated using the formula and recorded. Then, the extract was stored in a refrigerator at 4 ᵒ C until further use (Krakowska-Sieprawska et al, 2022). (Benzie & Strain, 1999).…”