Bioconversion of Alkali Pretreated Hazelnut Shells to Fermentable Sugars for Generation of High Value Products

Uzuner, Sibel
Shivappa, Ratna Rani Sharma
Çekmecelioğlu, Deniz
Hazelnut shells are lignocellulosic by-products of hazelnut processing. As the shells are rich in cellulose and hemicellulose, they have high potential as a raw material for production of food enzymes, biofuel, and various chemicals (acetic acid, furfural and lignin degradation products) after bioprocessing. The objective of this study was to determine the effect of alkali pretreatment and enzymatic hydrolysis on production of fermentable sugars from hazelnut shells. The hazelnut shells were pretreated with sodium hydroxide (NaOH) at concentrations of 3-7 % (w/v) for 30-90 min at 121 C-A degrees. Pretreatments were evaluated measuring delignification, solid recovery and production of reducing sugars after enzymatic hydrolysis of the pretreated biomass. Up to 20 % lignin removal was achieved and the highest reducing sugar yield of 318.3 mg/g pretreated biomass (or 91.7 % enzyme conversion efficiency) was obtained from biomass pretreated with 3 % NaOH at a solid to liquid ratio of 1:20 for 60 min. The response surface model predicted the optimal reducing sugar production (357.2 mg/g pretreated biomass) under 3 % NaOH, 1:13 of solid to liquid ratio and 63 min of pretreatment period at 121 degrees C. Overall, the results of this study show a promise for hazelnut shells to be used in production of value-added products.


Hydrolysis of Hazelnut Shells as a Carbon Source for Bioprocessing Applications and Fermentation
Uzuner, Sibel; Çekmecelioğlu, Deniz (Walter de Gruyter GmbH, 2014-12-01)
Hazelnut shells are generated in large amounts from hazelnut processing. Currently, it is used as fuel. However, reuse in bioprocessing can release remarkable content of sugars, which can be used for production of additives such as enzymes widely used in the food industry. Thus, the present study was undertaken to determine the effect of single and combined chemical and enzymatic hydrolysis on the production of fermentable sugars from hazelnut shells. Batch hydrolysis was carried out under various condition...
A rapid screening approach to factors affecting dilute acid hydrolysis of hazelnut shells
Uzuner, Sibel; Çekmecelioğlu, Deniz (null; 2013-05-19)
Hazelnut shell is a lignocellulosic waste obtained from hazelnut processing. It is a potential source of pentose and hexose sugars (xylose, glucose) which can be used as a raw material for production of food enzymes, biofuel, and chemicals (acetic acid, furfural, methanol). An increasing interest in lignocellulosic wastes seems to stay consistent as these materials are low cost, renewable and abundant. The objective of the present study was to determine the effect of dilute acid (H2SO4) concentration, tempe...
Cytotoxicity of 5-fluorouracil entrapped in gelatin microspheres
Muvaffak, A; Gurhan, I; Hasırcı, Nesrin (2004-05-01)
Gelatin microspheres were prepared by water/oil emulsion polymerization and by cross-linking with glutaraldehyde. For the microsphere preparation procedure, two different gelatin (5 or 10% w/v) and three different glutaraldehyde (5, 0.5 or 0.1% v/v) concentrations were used. The influence of preparation compositions on microsphere recovery, particle size and morphology, swelling and degradation, 5-fluorouracil loading and release, and cytotoxicity were investigated. The concentrations of gelatin and glutara...
Investigation of Physical Properties and Moisture Sorption Behaviour of Different MArshmallow Formulations
Kırtıl, Emrah; Öztop, Halil Mecit (2016-08-25)
Marshmallows are a type of confectionary product known for its soft, foamy texture. It owes this characteristic to its relatively high moisture content (17-21% by wt) and porous structure. However, these attributes make marshmallows more susceptible to quality degrading changes such as; sugar crystallization, texture aging, foam collapse and hardening or softening. The high interfacial area, increases the rates of mass transfer which makes it harder for marshmallows to preserve its initial moisture content ...
Optimising clarification of carrot juice by bacterial crude pectinase
Uzuner, Sibel; Çekmecelioğlu, Deniz (2015-12-01)
This study was undertaken to search for potential use of crude bacterial pectinase enzyme produced from Bacillus subtilis grown on hazelnut shell hydrolysate in clarification of carrot juice and to optimize the enzyme load, pH and time using the Box-Behnken response surface methodology (RSM). The carrot juice was treated with the crude pectinase enzyme (5.60 U mL(-1)) at different concentrations (0.1-0.5%), pH (4-7), and time (2-6 h). The obtained enzyme was also compared with commercial fungal pectinase at...
Citation Formats
S. Uzuner, R. R. S. Shivappa, and D. Çekmecelioğlu, “Bioconversion of Alkali Pretreated Hazelnut Shells to Fermentable Sugars for Generation of High Value Products,” WASTE AND BIOMASS VALORIZATION, pp. 407–416, 2017, Accessed: 00, 2020. [Online]. Available: