Browsing by Author "Saheed, Olorunnisola Kola"

Banana peel (BP) is a lignocellulosic waste generated by many cottage and hospitality industries in Malaysia. Based on the concept of waste to wealth coupled with availability of rich carbon sugars in BP, solid state bioconversion was used to produce bio-protein from the peel. Successful production of bio-protein from BP is expected to reduce solid waste management challenges. Hot water pre-treatment operation was conducted on dried BP and this reduced the amount of saponin present in the peels. Selection of potential combination of fungi and yeast cells was done based on the amount of bio-protein produced as yardstick. Media screening was performed by selecting potential media parameters and screening them based on their contribution by adopting Placket-Burman design. The number of fermentation days was scrutinized for economical bio-processing. Following selection of positively contributing media parameters, selected media were subjected to individual optimization by one-factor-at-a- time while full media optimization was carried out by adopting face centered central composite design (FCCCD) to obtain a maximum bio-protein production. Validation was done by conducting fermentation based on the suggested values of optimized media parameters to validate the parameters. The kinetics of product synthesis was conducted by subjecting bio-protein production to zero; first and second order reaction to ascertain which reaction kinetics best describe the production rate. Saponin content reduced between raw and normal washing from 9.50 mg/g to 9.0 mg/g. It was further reduced from 9.0mg/g to 7.5 mg/g between normal washing and soaking. Drastic reduction was witnessed between 20ºC and 100ºC (from 7.90mg/g to 5.7 mg/g) and 100ºC (5.7mg/g). This amount was enough for microbial growth to take place. Microbial screening results showed highest protein synthesis (88.93mg/g) with mixed culture of Phanerochaete chrysosporium (PC) and Candida utilis (CU). Based on the significant results from Plackett-Burman experimental design, solid content, KCl, MgSO4.7H2O, sucrose and NH4H2PO4 were positively contributing media parameters. A reduction in number of days required for fermentation was reduced from ten to six days after successful bio-processing with selected media parameters. Successful OFAT experimentation showed 27.5% was optimum for solid content, 0.5% for KCl, 0.4% for MgSO4.7H2O while 5% and 0.6% were optimum for sucrose and NH4H2PO4 respectively. The trend of total soluble sugar content (TOS), total reducing sugar content (TRS), ash content and total carbohydrate content (TC) were determined to study the degradation processes involved during fermentation. Following media optimization by FCCCD, the highest bio-protein production was achieved at 5% sucrose, 0.6% NH4H2PO4 and 0.4% MgSO4.7H2O. According to the numerical solution suggestion, highest protein of 105.223 mg/g was expected at 4.79% sucrose, 0.44% MgSO4.7H2O and 0.61% NH4H2PO4. Validation result showed 143.18mg/g as the true production. Zero order and first order reaction kinetics models best described bio-protein production with 0.0592h-1 and 0.2532h-1 rate constants. Their respective coefficient of determination (R2) was 0.951 and 0.812. Second order reaction kinetics gave 0.1507h-1 and R2 (0.6) respectively to be the least fit for the bio-protein production

Fruit wastes constitute high percentage of biodegradable residues emanating from fruit processing industries where they cause environmental challenges. These fruit wastes contained sufficient carbon source that can support fungi growth for conversion to animal feed supplement through biotechnological approach. Banana peel (Bp), pineapple peel (PAp) and papaya peel (Pp) were selected as substrates and the proximate analysis of the high solid content (HSC) type and low solid content (LSC) were performed. All samples contained simple and complex sugars that support fungi growth and development. Three white rot fungi –Phanerochaete chrysosporium (P. chrysosporium), Panus tigrinus (P. tigrinus) and Schizophyllum commune (S. commune), demonstrated profound growth and protein enrichment of the substrate with high enzyme secretion and elevated substrate consumption. Composite substrate from the three peels supported growth and protein enrichment by the fungi compared with individual substrates. All three fungi cells grew together on commercial media and formulated media. P. chrysosporium/P. tigrinus interaction and P. chrysosporium/S. commune interaction were deadlocked at contact, P. tigrinus/ S. commune interaction gave mutual intermingling while cultivation of the three together gave both deadlocked at contact and mutual intermingling. All microbial mixed cultures improved the protein secretion compared with their monocultures. Combination of P. chrysosporium and S. commune synthesized highest protein, enzymes and improved substrate consumption. Product synthesis in submerged phase bioconversion (SmB) was lower than solid state bioconversion (SSB); SSB was adopted after microbial interaction study. Substrate reformulation increased metabolizable sugar from 251 mg/g to 500 mg/g consisting 0.35g Bp, 5.5g PAp and 0.15g Pp; protein content increased from 104.22 mg/g to 160.68 mg/g. Media screening with Plackett-Burman design and optimization with face-centered-central composite design (FCCCD), gave KH2PO4 (1.2g/L), CaCl2 (0.8g/L) and peptone (0.8g/L) as media components. Protein synthesis increased to 175.23 mg/g. Optimum pH (5.4), inoculum size (6.1% ) and moisture content (70.2%) was achieved by FCCCD and protein synthesis increased to 198.77 mg/g. Kinetic study of biomass growth best fit with Monod equation (R2 = 0.936), µmax of 0.641 (day-1) and Ks of 23.35 mg/g. Haldane equation had R2 of 0.931, µmax of 0.644 (day 1) and Ki of 233.37 mg/g. Luedeking-Piret equation for substrate consumption gave R² of 0.9384; growth associated co-efficient (γ) of -49.08 mg/g and non-growth associated parameter (λ) of 48.862 mg/g/day. Product formation gave R² of 0.9888, growth associated co-efficient (α) of 0.0148 mg/g and non-growth associated parameter (β) of 0.0517 mg/g/day. Hanes-Woolf model fitted α-amylase (R² = 0.9108) and cellulase enzyme (R² = 0.9882) production. Km and Vmax of both were 11.55 Units/ml and 25.19 units/ml/day and 57.47 Units/ml, 3.05 units/ml/day respectively. Validation of parameters (media, process and kinetics) in 7 kg capacity reactor increased protein synthesis (228 mg/g), enzyme production, substrate consumption and improved productivity. Optimization of substrate depth and bioconversion period gave 2.5 cm as optimum depth and six days as optimum bioconversion period. Kinetics of in-vitro digestibility of flask optimized product and reactor, fitted into zero order model while nutritional analysis of final product showed great improvement in protein, amino acids and sugars.