Research Article
Efficient Bioethanol Production from Yam Peel Waste via Acid Hydrolysis and Fermentation
Issue:
Volume 13, Issue 6, December 2025
Pages:
167-178
Received:
28 September 2025
Accepted:
13 October 2025
Published:
22 November 2025
DOI:
10.11648/j.sjc.20251306.11
Downloads:
Views:
Abstract: Food residues can be transformed into bioethanol, reducing CO2 and methane emissions while fostering sustainable development. This method provides a cost-effective way to enhance the value of non-edible food sources. Thus, yam peels produced as agro-industrial waste is perfect starting material for bioethanol production. The main goal of this study is to evaluate the efficiency of bioethanol production from yam peels. Thus, fresh peels are subjected to wet milling to obtain a starch-rich powder. The hydrolysis of dry extracts, optimized according to time, acid concentration, and dry extract (DE)/water volume ratio, is carried out by reflux heating in the presence of different concentrations of H2SO4 used as a catalyst. The ethanolic fermentation of the hydrolysate musts, after adjusting the pH to 4.5, is conducted in batch mode using Saccharomyces cerevisiae. Fermentation monitoring is ensured by measuring °Brix with an Abbe refractometer, while the ethanol content is determined by the pycnometric method, in accordance with the recommendations of the Association of Official Analytical Chemists (AOAC). According to the results obtained, the optimal hydrolysis conditions include: an H2SO4 concentration of 8% (w/w), a dry extract (DE)/water volume ratio of 1:5 (g/mL), and a duration of 2 hours. These conditions yield an ethanol content of 6.72 ± 0.26% (v/v), corresponding to 264.97 ± 10.07 g EtOH/kg of dry matter. Wet milling provides better ethanol yields compared to dry milling. Finally, bioethanol production from yam peels prevents their degradation into CO2 and methane, which are greenhouse gases. The results from this study are important for the commercial production of bioethanol through a process of valorizing plant resources and reducing waste to promote the circular economy.
Abstract: Food residues can be transformed into bioethanol, reducing CO2 and methane emissions while fostering sustainable development. This method provides a cost-effective way to enhance the value of non-edible food sources. Thus, yam peels produced as agro-industrial waste is perfect starting material for bioethanol production. The main goal of this study...
Show More
Research Article
Synthesis of Novel 4-Imino-6,8-Dimethyl-2-(Methylthio)-4H-Pyrimido [1, 2-A] Pyrimidine-3-Carbonitrile and its 2- Substituted Derivatives
Nilesh Bhaurao Chavhan,
Shivraj Balajirao Sirsat*,
Anilkumar Govindrao Jadhav,
Sainath Laxman Shinde,
Suresh Sadanand Ardhapure,
Ajay Dashrath Munde
Issue:
Volume 13, Issue 6, December 2025
Pages:
179-184
Received:
29 September 2025
Accepted:
23 October 2025
Published:
22 November 2025
DOI:
10.11648/j.sjc.20251306.12
Downloads:
Views:
Abstract: In this study, we report a novel and efficient synthetic strategy for the construction of a fused bicyclic heterocyclic system with promising potential in medicinal chemistry. The synthesis begins with the reaction of ethyl bis(methylthio)methylene malononitrile with guanidine nitrate in the presence of potassium carbonate as a base, using dimethylformamide (DMF) as the solvent under reflux conditions. This reaction furnishes 2-amino-1,6-dihydro-6-imino-4-(methylthio)pyrimidine-5-carbonitrile as a key intermediate. Subsequent treatment of this intermediate with acetylacetone under acidic conditions initiates a Michael addition followed by a Robinson annulation, leading to intramolecular cyclization. This tandem sequence proceeds smoothly to afford the target compound, 4-imino-6,8-dimethyl-2-(methylthio)-4H-pyrimido[1,2-a]pyrimidine-3-carbonitrile in excellent yield. The synthesized compound was characterized by various spectroscopic techniques including IR, NMR, and mass spectrometry confirming its proposed structure. Notably, the target molecule contains a replaceable methylthio (-SCH₃) group at the 2-position making it a versatile precursor for further functionalization. The reactivity of this compound was explored through its reactions with different nucleophiles, such as substituted aromatic amines, aromatic phenols, heterocyclic amines, and active methylene compounds to afford a series of novel derivatives in good to excellent yields. Overall, this synthetic approach offers a convenient, efficient, and versatile route to access pyrimido[1,2-a]pyrimidine scaffolds which are of significant interest for the development of bioactive and pharmacologically relevant molecules.
Abstract: In this study, we report a novel and efficient synthetic strategy for the construction of a fused bicyclic heterocyclic system with promising potential in medicinal chemistry. The synthesis begins with the reaction of ethyl bis(methylthio)methylene malononitrile with guanidine nitrate in the presence of potassium carbonate as a base, using dimethyl...
Show More
,
Gnimdou Issanga Abli
