CITRUS SINENSIS (L) PEELS POTENTIAL FOR BIOFUEL PRODUCTION

This research work focused on the production of biofuel from orange peels using Bacillus subtilis as a fermentor. The orange peels were collected from Ekeukwu market and Ihiagwa fruit center, Owerri Nigeria, sun dried and grinded manually to powder. The sample was further fermented for 8days using Bacillus subtilis, after which it was distilled for 6 hours in order to extract the biofuel.Analysis of the ethanol compostion of orange peels was carried out using gas chromatography.The parameters measured include pH, concentration of reducing sugar before and after fermentation as well as the characterization of biofuel produced. Results shows that 200g of orange peels produced 400ml of biofuel on the 8th day of fermentation and the percentage component of the biofuel produced are Ethanol (48.73%), Methane (26.89%), Methanol (17.22%), Carbon dioxide (7.15%), Phenol (0.005%) while the control did not produce any biofuel. From the study it was observed that ethanol has the highest percentage in the biofuel produced from orange peels while phenol was the least. The reducing sugar concentration of the orange peel before and after fermentation were 11.678 mg/l and 73.899 mg/l respectively. It was also observed from this research that the ideal pH to obtain a reasonable quantity of biofuel from orange peels ranges from 5.0 – 5.3. The production of ethanol from orange peels presents an alternative, cheap, environmental friendly and readily available option to use in place of fossil fuels.The result from this study showed that liquid fuel (bioethanol) can be produced from the fermentation and distillation of orange peelsI therefore recommend that further studies be carried out on finding the efficient processes and methods of increasing the yield of biofuel from agro-waste.

PRETREATMENT OF MILLET HUSK USING ALKALINE HYDROGEN PEROXIDE TO ENHANCE ENZYMATIC HYDROLYSIS FOR REDUCING SUGAR PRODUCTION

The effectiveness of alkaline hydrogen peroxide as a suitable choice of pretreatment for the conversion of millet husk to reducing sugars using cellulase enzyme for hydrolysis and subsequent ethanol production was determined. The effects of three variables on reducing sugar production from millet husk were determined using one factor at a time (OFAT) method namely; peroxide concentration, pretreatment time and pretreatment temperature. From the results, it was observed that a significant (P<0.05) amount of reducing sugars were lost during pretreatment of millet husk. The untreated group which was only physically pretreated (milled) however yielded a significantly higher (P<0.05) reducing sugar concentration of 10.67mg/ml after enzymatic hydrolysis while the highest reducing sugar concentration of 4.82mg/ml was obtained using 0.375%v/v peroxide concentration for 60minutes at 250C. Therefore, pretreatment of biomass with alkaline hydrogen peroxide may be more suitable for feedstock with high lignin contents than millet husk.

Carotenoid Production by Rhodosporidium paludigenum Using Cassava Starch Hydrolyzed by Bacillus subtilis as Substrate

Carotenoids are natural pigments with colors ranging from yellow to red that are beneficial for food, cosmetics, and animal feed industries. These pigments can be found in fruits, vegetables, algae, and microorganisms. Among all microorganisms that have been known to produce carotenoids, Rhodosporidium paludigenum is still poorly investigated. Therefore, this study aimed to determine the potential of carotenoid production by R. paludigenum using cassava starch hydrolyzed by Bacillus subtilis as a substrate. The cassava starch for hydrolysis was divided into four concentrations, i.e., 2%, 4%, 6%, and 8% w/v. During the hydrolysis period, the amylase enzyme activity produced by B. subtilis was evaluated. The reducing sugar concentration was then examined to determine the optimum medium for carotenoid production. The highest amylase enzyme activity was produced on the second day in all cassava starch concentrations. However, the highest reducing sugar concentration was discovered in the 6% w/v cassava starch concentration. Thus, a batch submerged fermentation for carotenoid production by R. paludigenum was performed using the hydrolysate as the sole substrate. At the end of the fermentation, the total carotenoid was extracted, and the concentration was determined using spectrophotometry. The total yield of xanthophyll over biomass was higher than that of β-carotene. These findings elucidated the potency of cassava starch hydrolysate obtained from the starch hydrolyzed by B. subtilis, for carotenoid production by the red yeast R. paludigenum.

Study the Effect of pH on the Fermentation Anaerobic-Aerobic Siwalan (Borassus flabellifer L.) Sap to Produce Acetic Acid

This research is to study the effect of ethanol fermentation aerobic pH on acetic acid product. Anaerobic fermentation uses saccharomyces cerevisiae to produce ethanol, and aerobic fermentation uses acetobacter acetic for acetic acid production. In aerobic ethanol fermentation using pH 3; 3.5; 4 and 5. The ethanol concentration was evaluated using GC ULTRA Scientific Gas Chromatography, DSQ II detector, and MS 220 column. Acetic acid produced was analyzed using an alkalymetric method. Anaerobic fermentation uses Saccharomyces cerevisiae with 1-day log phase, while aerobic fermentation uses acetobacter aceti with a 5-day log phase. Fermentation using saccharomyces cerevisiae within 24 hours so that reduction sugar could stably decrease, optimum ethanol could be got at optimum pH 6 which could decrease 55 % of reducing sugar concentration to produce 8,20583 %v/v ethanol. Fermentation acetate acid content observed in 3 days at pH 6 and 30 ⁰C will produce 6,659 g/l also shows that pH 4-6 at 30 ⁰C will produce 6,605 g/l acetate acid. Aerobic fermentation of acetate acid in 3 days shows that pH 4-6 is highly affected by temperature at 30⁰C. Statistical analysis shows, in ethanol production pH and fermentation time give significant effect, but interaction has no significant effect.

The Effect of Variation on Solvent Type and Starch Extraction Time on the Increased Level of Reducing Sugar from Jackfruit Straw Waste

: Jackfruit straw is a part of jackfruit that does not experience pollination in the form of yellow fibers. Jackfruit straw has a composition consisting of 13.45% starch, 65.05% water. The potential content of jackfruit straw starch can be used as an alternative fuel, it was, bioethanol. This material can be converted to bioethanol through hydrolysis and fermentation processes. This study aimed to determine the effect of variations in the type of solvent and extraction time, used the type of solvent H2O, NaOH and NaHCO3 for starch which was then hydrolyzed and produced glucose as a raw material for making bioethanol. The initial content of jackfruit straw was carbohydrate of 11.5%, fat of 16.22% and protein of 8.38%. The first step was drying so that the jackfruit straw became powder with a moisture content <14%. Then extraction with a solvent to dissolve compounds that can interfere with the hydrolysis process such as fats and proteins. This research was conducted by extracting jackfruit straw powder into starch. Variation of the extraction process was the type of solvent (H2O, NaOH of 0.2%, and NaHCO3 of 0.2%) and the extraction time (5, 10, 15, 20, and 25 minutes) at room temperature. The results showed that the highest reducing sugar concentration of 2.16% was in the type of NaOH solvent for 25 minutes.

Biohydrolysis of Banana and Plantain Peels for the Production of Biofuel

This study was carried out to assess the potentials of banana and plantain peel as feedstock for biofuel production. Fungi were isolated from spoiled banana, burkutu and spoiled bread using the standard microbiological method. The concentration of reducing sugar of the peels were measured using DNS calorimetry method and biofuel were measured using chromium (VI) reagent by Ultraviolet-Visible Spectrophotometer. Aspergillus niger, Saccharomyces cerevisiae and Mucor racemusus were isolated. A reducing sugar concentration of 59.12 mg/g and 56.62 mg/g was observed for the banana and plantain peels. The highest concentration was found to be 0.35 mg/L for banana peels and 0.10 mg/L for plantain. The IR characterization of the banana and plantain sample revealed an intense strong broad band of alcohol O-H and alkane C-H stretching. The GC-MS result revealed the presence of benzaldehyde in all the biomass while 2,3-butanediol was only detected in the plantain peels biomass. This study showed the potential of banana and plantain peels biomass for biofuel production.

Effect of Dilute Acid and Alkaline Pretreatment of Typha australis (Typha Grass) for Bioethanol Production

Typha australis (Typha grass) obtained from Kware Lake was used in this research to produce bioethanol. Different pretreatment methods including dilute acid (0.2M H2SO4), dilute alkaline (0.2M NaOH) and liquid hot water pretreatments were used to pretreat the Typha grass sample before enzymatic saccharification for 7 days using Aspergillus niger isolated from soil sediment and the hydrolysate was seeded with Saccharomyces cerevisiae isolated from palm wine to produce bioethanol. HPLC was used to analyze bioethanol product. The result showed that pretreatment with 0.2M H2SO4 removed more hemicelluloses (7.0%) when compared with other pretreatment methods used, but pretreatment with 0.2M NaOH and liquid hot water removed more lignin (14.29%) than dilute acid pretreatment. The highest percentage reducing sugar concentration of 0.58% was obtained from lower part of the sample pretreated with liquid hot water while Typha grass pretreated with 0.2M H2SO4 and 0.2M NaOH produced the highest percentage reducing sugar concentration of 0.32% each from the upper part of the sample. Also, the highest Bioethanol concentration of 2.07% was obtained at day 6 of fermentation from the Typha grass pretreated with liquid hot water while Typha grass pretreated with 0.2M H2SO4 and 0.2M NaOH produced highest Bioethanol concentration of 0.43% and 0.54% respectively. The results indicate that Typha grass can be harnessed for bioethanol production thereby reducing their negative impact on Lakes.

Inhibitory Effects of Cyanide on the Activity of Granular Starch Hydrolyzing Enzyme (GSHE) during Hydrolysis of Cassava (Manihot Esculenta Crantz) Starch

The kinetics and inhibitory effects of cyanide on the granular starch hydrolyzing enzyme (GSHE) activity during hydrolysis of cassava (Manihot esculenta Crantz) starch at low temperature were studied. The substrates included native cassava starch at various concentrations (100-400 g/L) and native cassava starches with added cyanide at various concentrations (50-150 mg/kg), while the concentration of enzyme was 1.5% (w/w). A decrease in reducing sugar concentration during hydrolysis of cassava starch indicated that the cyanide reduced the enzyme activity. Lineweaver-Burk plot of Michaelis-Menten equation was used to study the inhibition kinetics. The maximum velocity (Vmax) value was higher for native cassava starch than that of native cassava starch with added cyanides. The presence of cyanide was found to reduce the Vmax values. No significant different of the saturation constant (Km) value between native cassava starch and native cassava starch with added cyanides was observed. Based on the inhibition type analysis, the effect of cyanide in the cassava starch can be classified as a noncompetitive inhibition, with the Ki value of 0.33 mg/L.

Waktu Optimum Hidrolisis Pati Limbah Hasil Olahan Ubi Kayu (Manihot esculenta Crantz var. Lahumbu) Menjadi Gula Cair Menggunakan Enzim α-Amilase Dan Glukoamilase

This study aims to determine optimum time of action of the enzyme α-amylase and glucoamylase needed in hydrolyze of starch from waste processed cassava (Manihot esculenta Crantz var. Lahumbu). This research was conducted through three main stages, namely the gelatinization, liquefaction and saccharification. The method was used method are liquefaction and saccharification. The variation time of the stage liquefaction: 12; 24; 36; 48; 60; and 72 minutes and the saccharification stage are: 9; 18; 27; 36; 45; 54; and 63 hours. The results showed that the optimum time required for stage liquefaction using α-amylase enzyme is 48 minutes on the condition of a temperature of 80 oC with a value of 0.09% amylose levels were measured using UV-Vis spectrophotometer. The optimum time required for saccharification step using a glucoamylase which is 54 hours on the conditions of a temperature of 50oC with the amount of reducing sugar concentration of 9.186 g/L as measured using a UV-Vis spectrophotometer.

Effects of different scouring methods on the catalytic efficiency of pectinase for cotton knitted fabrics

The application of bioscouring in cotton knitted fabrics should be improved owing to being a time-consuming process. In order to accelerate the bioscouring rate and shorten the bioscouring process, a repeated padding method is used on cotton knitted fabrics. The effect of the repeated padding with pectinase was studied by using FE-SEM and FTIR, and the catalytic rate was measured at different reaction temperatures, pick-up, and soaking times. The results observed in this study showed that during the bioscouring process for cotton knitted fabrics, the average catalytic rate of the repeatedly padding method was sixfold faster than the impregnation method, and the process time (15 min) decreased by 65 minutes compared with the impregnation method (80 min); the processing time was shortened to one-sixth of the impregnation method. Furthermore, the wettability of cotton knitted fabrics was better than those treated via impregnation. In the repeated padding process, with the soaking time increasing from 5 s to 25 s, the produced reducing sugar concentration increased from 1.71 mg/ml to 3.60 mg/ml in the same process time; with the pick-up increased from 50% to 90%, the produced reducing sugar concentration first increased from 1.99 mg/ml to 3.60 mg/ml, then decreased to 1.86 mg/ml. When the pick-up was about 70%, the catalytic rate of pectinase reached the best value (0.24 mg/ml/min).