Agave By-Products: An Overview of Their Nutraceutical Value, Current Applications, and Processing Methods

Abstract

Agave, commonly known as “maguey” is an important part of the Mexican tradition and economy, and is mainly used for the production of alcoholic beverages, such as tequila. Industrial exploitation generates by-products, including leaves, bagasse, and fibers, that can be re-valorized. Agave is composed of cellulose, hemicellulose, lignin, fructans, and pectin, as well as simple carbohydrates. Regarding functional properties, fructans content makes agave a potential source of prebiotics with the capability to lower blood glucose and enhance lipid homeostasis when it is incorporated as a prebiotic ingredient in cookies and granola bars. Agave also has phytochemicals, such as saponins and flavonoids, conferring anti-inflammatory, antioxidant, antimicrobial, and anticancer properties, among other benefits. Agave fibers are used for polymer-based composite reinforcement and elaboration, due to their thermo-mechanical properties. Agave bagasse is considered a promising biofuel feedstock, attributed to its high-water efficiency and biomass productivity, as well as its high carbohydrate content. The optimization of physical and chemical pretreatments, enzymatic saccharification and fermentation are key for biofuel production. Emerging technologies, such as ultrasound, can provide an alternative to current pretreatment processes. In conclusion, agaves are a rich source of by-products with a wide range of potential industrial applications, therefore novel processing methods are being explored for a sustainable re-valorization of these residues.

Agave Syrup: Chemical Analysis and Nutritional Profile, Applications in the Food Industry and Health Impacts

“…For the textile industry, although spines and stalks are less commonly employed, they are a relevant source of biocolorants, fibers and bioactive compounds, which can serve as substrates for saccharification. Traditionally, cuticles have been utilized to wrap meat preparations of lots of Mexican dishes and to manufacture paper [ 38 ]. Varieties such as Agave salmiana , Agave sisalana (sisal) and Agave mapisaga yield hard fibers, which are highly appreciated because they can be employed to make string and ethnic clothing, and their durability stands out [ 39 ].…”

“…Some 7,710,520 tons of residual bagasse were produced between 1995 and 2019 [ 40 ]. Otherwise, bagasse is an excellent source of bioactive compounds (phenolic compounds, fructans and saponins), sugars, fibers, and other valuable biomolecules [ 38 ].…”

Enhancement of sustainable fused deposition modeling 3D‐printing with agave Americana fiber‐reinforced poly(lactic) acid biofilaments

“…19,20 Agave fibers are composed of cellulose (68.4%), lignin (4.9%), hemicellulose (15.7%), 21 and the remaining 11.06% in fructans, pectins, and other simple carbohydrates. 22 This work aimed to prepare an innovative filament of Agave fibers as filler in PLA, obtaining eco-friendly composite filament for AM. The Agave fibers' influence on PLA filament chemical structure (FTIR), thermal properties (TGA), morphology (MO), and density were investigated in detail, and the developed filament showed potential for several applications in AM, which could expand PLA usage.…”

“…However, only 4 wt% of the harvested leaves are converted into a marketable product 19,20 . Agave fibers are composed of cellulose (68.4%), lignin (4.9%), hemicellulose (15.7%), 21 and the remaining 11.06% in fructans, pectins, and other simple carbohydrates 22 …”

A New Preparation Method for 3D Bio-composite Filament Manufacturing: a Study on the Effects of Ball Milling on the Cohesion/Adhesion of an Agave tequilana Bagasse/PLA Pellet Mixture

“…To date, possible routes for valorisation and upcycling of agave bagasse have demonstrated the viability and versatility of this by-product. This includes bagasse reuse to produce biofuel [12], activated carbons [13], adobes reinforced with agave fibres [14], MDF boards [15], nutraceutical compounds [16], other valuable biochemical compounds [17] and bagasse-based composites [18]. Agave leaves have also been used to obtain fibres by mechanical extraction [19].…”