Coffee is the second largest traded commodity in the world and also produces by-products and residues. Coffee husk waste is an abundant lignocellulosic material and has the potential to be used as raw material for biogas production. This study compared the production of biogas from coffee husk using rumen fluid with a mixture of rumen fluid and cow dung. In the pretreatment process using ethanol, the waste consisted of 65.90% cellulose, 24.95% hemicellulose, 0.21% lignin, 2.16% pectin, 1.08% protein, 3.11% tannins, 0.91% caffeine, and 3.78% polyphenols. The decrease in TS (total solid) and VS (volatile solid) values for C-RC (coffee-rumen fluid-cow dung) was greater than for C-R (coffee-rumen fluid) as 32.20% and 42.47% were obtained for C-RC, while the values for C-R were 19.32% and 38.37 The VFA (volatile fatty acids) values for C-R and C-RC were 1.09% and 2.24%. The biogas produced for C-R was CH4 of 14.4%, CO2 of 13.75%, and H2 of 0.59%, while that for C-RC consisted of CH4 of 22.3%, CO2 of 4.11%, and H2 of 0.36%. The yield of biogas for C-R was 0.48 Nm3/(kg COD removal) and for C-RC was 1.95 Nm3 /(kg COD removal).

The present work aimed to evaluate the effect of fermentation by Rhizopus oryzae on the proximate composition, anti-nutrient contents, and functional properties of banana peel flour using the solid-state fermentation method in a tray bioreactor at 30°C for 96 h. Throughout fermentation, samples were obtained at different times (0/NF, 24, 48, 72, and 96 h), and analysed using standard procedures to determine the proximate composition, anti-nutrient contents, and functional properties. Based on the results, there were significant differences observed (p < 0.05). Carbohydrate content decreased by 3.35%, while the crude protein, fat, ash, and crude fibre contents increased by 11.12, 2.43, 10.99, and 3.50%, respectively. Hydrogen cyanide, saponin, oxalate, and phytate contents decreased by 42.59, 25, 23.83, and 43.82%, respectively. Water absorption capacity (WAC) and the water solubility index (WSI) increased by 3.94 and 37.14%, respectively, while oil absorption capacity (OAC) decreased by 4.48%. These results showed that the fermentation of banana peel flour by R. oryzae has potential benefits for the food industry due to its effect on chemical composition and functional properties.

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Coffee husk is a lignocellulosic material which is abundant and can be used to produce biogas. This study compares the production of biogas produced from coffee husk substrate using cow dung and a mixture of cow dung and effective microorganisms. This experiment was carried out for 30 days in an anaerobic batch reactor with a reactor working volume of 3.6 L at mesophilic temperature. The parameters tested in this study were the lignocellulosic content of coffee husks, total solids (TS), volatile solids (VS), volatile fatty acids (VFA), chemical oxygen demand (COD), and the content of biogas produced from both variables. The lignocellulosic compositions obtained from this study were cellulose 65.90%, hemicellulose 24.95%, lignin 0.21%, pectin 0.42%, protein 0.81%, tannins 1.05%, caffeine 0.09%, and polyphenols. The values of Total Solids and Volatile Solids for the two variables are K-KS of 16.78% and 33.98% and K-KSEM of 24.87% and 48.42%, respectively. The total VFA for the two variables is 2.06% (v/v) for K-KS and 2.36% (v/v) for K-KSEM. The COD values for the K-KS and K-KSEM variables were 78.05% and 81.42%, respectively. The composition of biogas for K-KS is CH4 12.35%, CO2 21.68%, and H2 0.32%, while for K-KSEM it is CH4 19.64%, CO2 2.82%, and H2 0.35 %. The methane yields for the two variables, K-KS and K-KSEM, were 0.76 Nm3/kgCODremoval and 1.43 Nm3/kgCODremoval, respectively.Key words: anaerobic digestion, cow dung, rumen fluid, effective microorganism (EM), methane

Zeolite is a hydrated alumino-silicate compound having a main element which consists of alkali and alkaline-earth cations, especially Ca, K and Na, with a general formula (LmAlx Sig O2nH2O) where L is a metal. Zeolite can be synthesized from a sample containing silica and alumina. The compounds contain alkali hydroxide or organic bases. Palm kernel shells are one of the industrial wastes containing many minerals such as SiO2 58.02%; Al2O3 8.7%. The source of silica and alumina in oil palm shells is used as a base for making zeolites using the hydrothermal method in a reactor. Fine samples of palm shells were melted with NaOH at 500 °nn C for 1 hour and diluted to produce sodium silicate reactants. Making sodium aluminate reactant is done by dissolving NaOH in distilled water and then heating and adding Al(OH)3 to NaOH solution with stirring. Making zeolite is done by mixing sodium silicate and sodium aluminate reactants and the zeolite crystallization process is carried out using a hydrothermal reactor heated in the oven by varying the hydroternal temperature of 1200C, 150 ° C and 1800C for 8 hours. The synthesized zeolite was characterized using XRF, FTIR and SEM EDX.