More than sweet: A phytochemical and pharmacological review of sugarcane (Saccharum officinarum L.)

Recent developments in sugarcane bagasse fibre-based adsorbent and their potential industrial applications: A review

In recent years, there has been an increase in research devoted to the advancement of cellulose and nanocellulose-based materials, which are advantageous due to their renewable nature, strength, rigidity, and environmental friendliness. This exploration complies with the fundamental tenets of environmental stewardship and sustainability. An area of industrial biotechnology where cellulosic agricultural residues have the potential to be economically utilized is through the conversion of such residues; sugarcane bagasse is currently leading this charge. SCB, a plentiful fibrous byproduct produced during the sugarcane industry's operations, has historically been utilized in various sectors, including producing paper, animal feed, enzymes, biofuel conversion, and biomedical applications. Significantly, SCB comprises a considerable amount of cellulose, approximately 40 % to 50 %, rendering it a valuable source of cellulose fibre for fabricating cellulose nanocrystals. This review sheds light on the significant advances in surface modification techniques, encompassing physical, chemical, and biological treatments, that enhance sugarcane bagasse fibres' adsorption capacity and selectivity. Furthermore, the paper investigates the specific advancements related to the augmentation of sugarcane bagasse fibres' efficacy in adsorbing a wide range of pollutants. These pollutants span a spectrum that includes heavy metals, dyes, organic pollutants, and emerging contaminants. The discussion provides a comprehensive overview of the targeted removal processes facilitated by applying modified fibres. The unique structural and chemical properties inherent in sugarcane bagasse fibres and their widespread availability position them as highly suitable adsorbents for various pollutants. This convergence of attributes underscores the potential of sugarcane bagasse fibres in addressing environmental challenges and promoting sustainable solutions across multiple industries.

Phase controlled green synthesis of wurtzite (P63mc) ZnO nanoparticles: interplay of green ligands with precursor anions, anisotropy and photocatalysis

Green approaches for nanosynthesis often lack the precise control of synthetic outcomes, which is primarily due to the poorly defined reaction protocols. Herein, we investigated the use of lignocellulosic agro-waste, sugarcane press mud (PM), for the synthesis of ZnO nanoparticles using three different precursor salts and their further application in the photocatalytic degradation of rhodamine dyes. This approach resulted in the formation of ZnO nanoparticles with two different morphologies, i.e., sheet-like structure from the zinc sulphate and nitrate precursors, whereas sphere-like structures from zinc acetate. In all three cases, the wurtzite phase (P63mc) of ZnO nanoparticles remained consistent. Also, the ZnO nanoparticles were found to be positively charged ("ζ" = +8.81 to +9.22 mv) and nearly monodispersed, with a size and band gap in the range of ∼14-20 nm and 3.78-4.1 eV, respectively. Further, the potential photocatalytic activity of these nanoparticles was investigated under direct sunlight. At the same photocatalyst dose of 0.1 g L-1, the three ZnO nanoparticles showed varying efficiencies due to their shape anisotropy. The ZnO NPs from acetate salt (∼20 nm, sheet like) showed the highest dye degradation efficiency (90.03%) in 4.0 hours, indicating the role of the catalyst-dye interface in designing efficient photocatalysts.

Toward Sustainable Wax Extraction from the Saccharum officinarum L. Filter Cake Byproduct: Process Optimization, Physicochemical Characterization, and Antioxidant Performance

Saccharum officinarum L. exploitation and processing result in different byproducts, such as filter cake (FC). This study aimed to establish the most suitable experimental conditions to obtain lipophilic bioactive compounds from FC industrial residues, considering their high efficiency, cost-effectiveness, extraction yield, composition, and physicochemical properties. Results indicated that the most appropriate methodology consisted of the pretreatment of the FC sample with H2SO4, followed by ethanolic extraction (B6 method), avoiding energy-consumption FC drying steps and providing ethanol recovery (approx. 90%). The obtained B6 extract yield was 9.59 ± 0.27 g/100 g of FC dry weight, and this methodology proved to be more efficient in obtaining fatty alcohols (20.28 ± 1.48 g/kg extract) and phytosterols (31.56 ± 0.18 g/kg extract) while maintaining lower total monosaccharide concentration (26.19 ± 1.82 mg/g extract). Furthermore, the geographically related multivariate analysis in wax composition and antioxidant activity was evaluated by comparing B6 waxes from Guariba (G) and Univalem (U), both provided by Brazil and collected in June 2020. Overall, the wax composition is affected, but the antioxidant activity is uncompromised, which indicates that the optimized wax extraction method can be applied to FC.

Green, zero-waste pathway to fabricate supported nanocatalysts and anti-kinetoplastid agents from sugarcane bagasse

The conversion processes of sugarcane into direct-consumption sugar and juice are generating a tremendous amount of waste, the so-called sugarcane bagasse (SCB). Biochar preparation is among the practical solutions aiming to manage and valorize SCB into high added-value functional material (FM). Herein, we propose a novel zero-waste pathway to fabricate two FMs from one biomass. The SCB was first macerated and ultrasonicated to obtain the natural extract that served as bio-reducing medium. Then, the H₂O/EtOH-extracted SCB was in-situ impregnated with a bimetallic solution of copper and silver nitrates. The process produced an intermediate composite (FM₀), Ag/Cu-Ag⁺/Cu²⁺-loaded SCB which was carbonized to elaborate Ag/Cu-Biochar (FM₁), free Ag/Cu nanoparticles (FM₂) were obtained by microwaving the residual liquid waste. FM₁ exhibited high catalytic activity for the total Fenton-like degradation of methylene blue. The experimental data followed the pseudo-first and the pseudo-second order rate laws with apparent degradation rate constants K₁ 45 10^-3 min^-1 and K₂ 0.115 g.mg^-1.min^-1, respectively. FM₀, FM₁ and FM₂ were tested as new anti-kinetoplastid materials against two flagellated protozoans namely the Leishmania spp and the Trypanosoma cruzi. Notably, Ag/Cu (FM₂) showed exceptional leishmanicidal and trypanocidal effects with IC₅₀ values of 2.909 ± 0.051, 3.580 ± 0.016 and 3.020 ± 0.372 ppm for L.donovani, L. amazonensis and Trypanosoma cruzi, respectively. In this way, we combine green chemistry and agrowaste valorization in a full zero-waste process, to address the 3rd (indicator 3.3.5) and 6th (indicator 6.3.1) United Nations sustainable development goals, ″Good Health and Well-Being″ and ″Clean Water and Sanitation″.

Sugarcane Straw Polyphenols as Potential Food and Nutraceutical Ingredient

The sugarcane processing industry generates a large amount of straw, which has a negative environmental impact, and high costs are associated with their elimination, wasting their potential bioactive value attributed to their richness in polyphenols. In this study, an ethanolic extract produced from sugarcane straw was screened for its phenolic compounds content, and the potential use of this extract in the development of a food ingredient was further evaluated. Fifty different secondary metabolites belonging to the hydroxybenzoic acids, hydroxycinnamic acids, and flavonoids were identified by liquid chromatography-electrospray ionization-ultrahigh-resolution-quadrupole time of flight-mass spectrometry (LC-ESI-UHR-QqTOF-MS). The predominant phenolic compounds found were 4-hydroxybenzaldehyde, chlorogenic acid, and 5-O-feruloylquinic acid. The obtained extracts showed strong potential as food preservatives by exhibiting (a) antioxidant activity using both 2.2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt radical cation (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods; and (b) antimicrobial capacity, with a minimum inhibitory concentration of 50 mg/mL for Staphylococcus aureus, 74% inhibition for Bacillus cereus, and 44% for Salmonella enterica; and (c) the capacity to inhibit a food browning enzyme, tyrosinase (28-73% for 1-8 mg/ mL). Moreover, the extracts showed antidiabetic potential by inhibiting the enzymes α-glucosidase (15-38% for 1.25-5.00 mg/mL) and dipeptidyl peptidase-IV (DPP-IV) (62-114% for 0.31-5.00 mg/mL). The extract (0.625 mg/mL) also exhibited the capacity to reduce proinflammatory mediators (i.e., interleukins 6 and 8, and tumor necrosis factor alpha) when Caco-2 cells were stimulated with interleukin 1 beta. Thus, sugarcane straw extract, which is rich in phenolic compounds, showed high potential to be used in the development of food-preservative ingredients owing to its antioxidant and antimicrobial potential, and to be explored as a food supplement in diabetes prevention and as coadjuvant to reduce intestinal inflammation by reducing proinflammatory mediators.