Analysis of Five-Extraction Technologies’ Environmental Impact on the Polyphenols Production from Moringa oleifera Leaves Using the Life Cycle Assessment Tool Based on ISO 14040

Abstract

The present study examines, compares, and documents the environmental impact of five extraction techniques through Life Cycle Assessment (LCA). The material used was Moringa oleifera freeze-dried leaves and the assessment was based on their polyphenol content Three out of the five examined techniques are referred to in the literature as “green” techniques, namely Pulsed Electric Field (PEF), Microwave-Assisted Extraction (MAE), and Ultrasound-Assisted Extraction (UAE). The other two examined were conventional extraction techniques and, specifically, boiling water and maceration; the latter served as a control in this study. The analysis utilized special software (SimaPro ecoinvent) for the “cradle to gate” LCA, along with a sensitivity analysis of the model examining the variation in the environmental impact based on the origin of the source of electricity (renewable sources such as photovoltaic arcs), aiming to highlight the optimal technology choice. This LCA study's Functional Unit (FU) was one gram (g) of extracted total polyphenols (dry) produced by a case-specific number of extraction cycles for each technology under assessment (considering their technical efficiency depicted as polyphenols yields), measured by the Folin–Ciocalteu method and expressed as mg Gallic Acid Equivalents per g of dry Moringa oleifera leaves. The study outcome indicates that PEF and MAE deliver the best environmental scores. The main contributing parameters are the Moringa oleifera leaves and the amount and origin of electricity used to make 1 FU. These parameters are dominant in the categories of freshwater ecotoxicity, marine ecotoxicity, human carcinogenic toxicity, and human non-carcinogenic. The better performance of these two techniques is due to the more efficient extraction with reduced electricity consumption, which can become even more environmentally friendly if replaced with renewable sources such as photovoltaic arcs.

Sustainability Assessment of Pectin Extraction From Citrus Paradisi Peel and Application in Encapsulating Lactiplantibacillus Plantarum Cidca 83114

“…Differences in the various components of LCA studies (such as functional units, system boundaries, laboratory or industrial scale and impact assessment methods) will be considered for comparing the presented results with other studies. However, several studies show differences between traditional extraction methods and green ones, with the latter being more e cient and environmentally friendly (García-García et al, 2019;Pappas et al, 2023). In agreement with the results of this work,Wang et al (2015) reported that ultrasound-assisted heating extraction was an e cient and economical method to obtain higher pectin yields at lower temperatures and shorter extraction times than CHE from grapefruit peel.…”

Combining DoE and MASE: a winning strategy for the isolation of natural bioactive compounds from plant materials

“…Regarding the in-depth description of specific experimental designs, models, and details concerning the statistics involved in using these tools, interested readers are referred to the fundamental literature on the subject. [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21]27 The last part of the experimental design involves transforming the data obtained into information and their analysis. The model must be examined to determine if it shows good predictability; this means that it must adequately represent the response function in the experimental domain.…”

“…Regarding the in-depth description of specific experimental designs, models, and details concerning the statistics involved in using these tools, interested readers are referred to the fundamental literature on the subject. 5–21,27…”

“…This last aspect is guaranteed by both the drastic reduction in time and the gram to kilo scale in which the extractions are usually performed. 15,16 Unfortunately, this last aspect is not always considered during the set-up of a new method, since the amount of natural matrix exploited in this phase typically ranges from hundreds of milligrams to a few grams, thus limiting the energy saving usually associated with MASE. Consistently, curtailing the number of experiments required to identify the best extraction conditions and applying a DoE model is mandatory to make the most of MASE potential.…”

“…In this work, the authors concluded that its better performance is due to the more efficient extraction with reduced electricity consumption. 15 The different results obtained considering microwave-assisted organic synthesis and MASE can be explained considering that extractions of natural matrices are performed on tens of grams to a kilo scale 16 As stated in the literature, these scales are associated with an improvement in energy efficiency on a kJ mol −1 basis. 17 Moreover, also the already cited significant saving of time plays a pivotal role in reducing energy consumption.…”