Sustainable Extraction and Characterisation of Bioactive Compounds from Horse Chestnut Seed Coats for the Development of Bio-Based Additives

Abstract

Background: To protect renewable packaging materials against autoxidation and decomposition when substituting harmful synthetic stabilizers with bioactive and bio-based compounds, extracts from Aesculus hippocastanum L. seeds were evaluated. The study objectives were to determine the antioxidant efficacy of bioactive compounds in horse chestnut seeds with regard to different seed fractions, improve their extraction, and to evaluate waste reuse. Methods: Different extraction techniques for field samples were evaluated and compared with extracts of industrial waste samples based on total phenolic content and total antioxidant capacity (2,2’-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS)). The molecular weight distribution and absorbance in ultraviolet range (UV) of seed coat extracts were determined, and the possibility of extracts containing proanthocyanidins was examined. Results: Seed coat extracts show a remarkable antioxidant activity and a high UV absorbance. Passive extractions are efficient and much less laborious. Applying waste product seed coats leads to a reduced antioxidant activity, total phenolic content, and UV absorbance compared to the field sample counterparts. In contrast to peeled seed extracts, all seed coat extracts contain proanthocyanidins. Discussion: Seed coats are a potential source of bioactive compounds, particularly regarding sustainable production and waste reuse. With minimum effort, highly bioactive extracts with high potential as additives can be prepared.

Underutilised Resources in Urban Environments

“…Table 1 shows that there are interlinkages between circular economy and renewable energy schemes. Seven out of the ten publications address solid wastes and their potential valorisation as part of circular economy schemes [3][4][5][6][7][8][9], which can be material recycling or energetic valorisation. Source-segregated waste destined for energetic valorisation is considered a source of renewable energy; four out of the seven manuscripts which address solid wastes are closely linked to renewable energy, and therefore fall into both categories of circular economy and renewable energy.…”

A Mechanistic Model of Mass Transfer in the Extraction of Bioactive Compounds from Intact Sorghum Pericarp

“…A range of phytochemical compounds, as secondary metabolites of plants [8], are naturally contained in some plants as well as red sorghum grains. The phytochemical compounds in red sorghum, including polyphenols, phenolic acids, flavonoids, and condensed tannins of proanthocyanidins [9], are concentrated on the external layer of the grain, which is known as pericarp. These compounds have proven to have beneficial health effects, such as antioxidant, anti-proliferative, UV adsorption, and antimicrobial activities [9][10][11].…”

“…Furthermore, some studies focused on designing new methods of extraction that were safe, cheap, efficient, and effective in producing extracts in a high quantity and of high quality [4,8,[15][16][17][18][19]. Several techniques were developed to obtain standard extraction procedures to be applied for the extraction of functional compounds to meet the needs of the pharmaceutical, food, and chemical industries [1,9,[20][21][22].…”

“…Commonly, the extraction of bioactive compounds from sorghum is carried out while using conventional methods that apply hot water and maceration to sorghum bran [9,19]. Maceration and hot water extraction are basic methods of solid-liquid extraction for separating and isolating active compounds from their original locations in the plant body [1] as well as for transferring them into the solvent, a process that is usually driven by natural convection.…”

“…This method has the potential to be applied in the production of pharmaceutical and food additives. It was evaluated by measuring its efficiency, cost, and energy consumption and the quantity and quality of the extracted compounds [9].…”