Extraction, Addition and Characterization of Hemicelluloses from Corn Cobs to Development of Paper Properties

Silva, Juliana Cristina da; Oliveira, Rubens Chaves de; Neto, Armando da Silva; Pimentel, Vanessa Cunha; Santos, Allan de Amorim dos

doi:10.1016/j.mspro.2015.04.137

Cited by 33 publications

(15 citation statements)

References 16 publications

(25 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To investigate possible boosting of lignocellulose hydrolysis through bacterial GE action, selected CE15 enzymes were added to the cellulo- and hemicellulolytic cocktail Ultraflo ® during hydrolysis of ball milled corn cob (no further pretreatment was performed to limit disruption of the chemical structure). Corn cobs are abundant industrial waste streams, consisting chiefly of cellulose (47% dry weight; dw), but are also rich in complex heteropolysaccharides (heteroxylans, 28% dw, and arabinan, 5% dw) [ 31 ]. The GEs Sl CE15A, Su CE15A or Su CE15C were selected to supplement hydrolysis reactions based on their high activity on BnzGlcA at pH 5.5 (recommended for Ultraflo ® ) together with their high long-term stabilities.…”

Section: Resultsmentioning

confidence: 99%

Biochemical and structural features of diverse bacterial glucuronoyl esterases facilitating recalcitrant biomass conversion

Bååth

Mazurkewich

Knudsen

et al. 2018

Biotechnol Biofuels

View full text Add to dashboard Cite

BackgroundLignocellulose is highly recalcitrant to enzymatic deconstruction, where the recalcitrance primarily results from chemical linkages between lignin and carbohydrates. Glucuronoyl esterases (GEs) from carbohydrate esterase family 15 (CE15) have been suggested to play key roles in reducing lignocellulose recalcitrance by cleaving covalent ester bonds found between lignin and glucuronoxylan. However, only a limited number of GEs have been biochemically characterized and structurally determined to date, limiting our understanding of these enzymes and their potential exploration.ResultsTen CE15 enzymes from three bacterial species, sharing as little as 20% sequence identity, were characterized on a range of model substrates; two protein structures were solved, and insights into their regulation and biological roles were gained through gene expression analysis and enzymatic assays on complex biomass. Several enzymes with higher catalytic efficiencies on a wider range of model substrates than previously characterized fungal GEs were identified. Similarities and differences regarding substrate specificity between the investigated GEs were observed and putatively linked to their positioning in the CE15 phylogenetic tree. The bacterial GEs were able to utilize substrates lacking 4-OH methyl substitutions, known to be important for fungal enzymes. In addition, certain bacterial GEs were able to efficiently cleave esters of galacturonate, a functionality not previously described within the family. The two solved structures revealed similar overall folds to known structures, but also indicated active site regions allowing for more promiscuous substrate specificities. The gene expression analysis demonstrated that bacterial GE-encoding genes were differentially expressed as response to different carbon sources. Further, improved enzymatic saccharification of milled corn cob by a commercial lignocellulolytic enzyme cocktail when supplemented with GEs showcased their synergistic potential with other enzyme types on native biomass.ConclusionsBacterial GEs exhibit much larger diversity than fungal counterparts. In this study, we significantly expanded the existing knowledge on CE15 with the in-depth characterization of ten bacterial GEs broadly spanning the phylogenetic tree, and also presented two novel enzyme structures. Variations in transcriptional responses of CE15-encoding genes under different growth conditions suggest nonredundant functions for enzymes found in species with multiple CE15 genes and further illuminate the importance of GEs in native lignin–carbohydrate disassembly.Electronic supplementary materialThe online version of this article (10.1186/s13068-018-1213-x) contains supplementary material, which is available to authorized users.

show abstract

Section: Resultsmentioning

confidence: 99%

Biochemical and structural features of diverse bacterial glucuronoyl esterases facilitating recalcitrant biomass conversion

Bååth

Mazurkewich

Knudsen

et al. 2018

Biotechnol Biofuels

View full text Add to dashboard Cite

show abstract

“…Enoxaparin sodium Clexane® was from Sanofi-Aventis S.A. (Bogotá, Colombia). Hemicelluloses from corn cobs were obtained by alkaline extraction at room temperature following the methodology described in literature (Da Silva et al., 2015). Mucilage from chia seeds ( Salvia hispanica ) was obtained at pH 6 and room temperature in accordance to Muñoz et al.…”

Section: Methodsmentioning

confidence: 99%

Coumarins from the peel of citrus grown in Colombia: composition, elicitation and antifungal activity

Ramírez-Pelayo

Martínez-Quiñones

Gil

et al. 2019

Heliyon

View full text Add to dashboard Cite

The present work analyses the chromatographic profile of the peels from fruits of different citrus cultivated in Colombia: sweet orange ( Citrus sinensis [L.] Osbeck var. Valencia), mandarins ( Citrus reticulata L. var. Arrayana and Oneco), Key lime ( Citrus aurantifolia [Christ.] Swingle var. Pajarito), Mandarine lime ( Citrus x limonia , a hybrid between Citrus reticulata and Citrus x limon ) and Tahitian lime ( C. latifolia Tanaka, syn. Persian lime). Coumarins, furanocoumarins and polymethoxylated flavones are the major compounds. Then, six coumarins were isolated and identified from fruits of Tahitian and Key lime corresponding to 5-geranyloxy-7-methoxycoumarin; 5,7-dimethoxycoumarin ( syn . limettin); 5,8-dimethoxypsoralen ( syn. isopimpinellin); 5-methoxypsoralen ( syn . bergaptene); 5-geranoxypsoralen ( syn. bergamottin) and 5-(2,3-dihydroxy-3-methylbutoxy) psoralen ( syn. oxypeucedanin hydrate). Coumarins and furanocoumarins were quantified by liquid chromatography (HPLC-DAD). Results show that the prenylated compounds were present in high concentrations in Tahitian and Key lime but in very low amounts in mandarins and sweet orange. Subsequently, the antifungal activity (inhibition of mycelial growth and germination of spores) of the coumarins against the fungus causing the anthracnose, Colletotrichum sp. (isolated from aerial parts of Tahitian lime) was determined. The compounds limettin and bergaptene, as well as mixtures of them, showed significant inhibitory effect (radial growth and spore germination) when compared to the control. Finally, the effect of some recognized elicitors to induce the coumarin production in fruits of C. latifolia was evaluated. The results showed that the chemical profiles are dependent on the applied elicitor and the post-induction time. As a result of the induction, a high concentration of some coumarins and furanocoumarins was maintained in the course of time for the Tahitian lime. In conclusion, isolated coumarins could be involved in the defense mechanisms of C. latifolia , C. aurantifolia and C. limonia and their accumulation may be modulated by the application of elicitors.

show abstract

“…It is also considered the central core of the maize ear with a residual yield of 1.42-1.53 dry tons per hectare. Consequently, corn cobs are major by-products of corn processing, which account for 20-30% (along with the outer leafy covering of corn called husks) by weight of the corn plant (Kapoor et al, 2016;Samanta et al, 2012). Da Silva et al (2015 report that typically 180 kg of corn cob are generated from the processing of 1 ton of corn ear.…”

Section: Corn Cobs: Overview and Current Usesmentioning

confidence: 99%

Utilization of Corn Cobs Ash as Cementitious and Binary Cementitious Materials in Concrete and Cement-based Composites: A Review

2021

DRCSF

View full text Add to dashboard Cite

This paper reviews the utilization of corn cobs ash (CCA) as pozzolanic, cementitious, and binary cementitious materials in concrete. CCA is the grey-to-brown, inorganic or heterogeneous residual material derived from the high- temperature incineration or combustion of corn cobs (CC). Despite the typical problematic nature of biomass ash, the chemical composition of CCA renders it a potential pozzolanic material. Therefore, numerous studies have critically examined the process technologies and operational conditions for CCA production and its application as a partial replacement for cement in concrete. Other studies have extensively characterized the physicochemical, morphological, microstructure, and thermal properties of CCA through various analytical techniques. Potential pozzolanic materials must meet the condition: SiO2 + Al2O3 + Fe2O3 ≥ 70%, according to ASTM C618, to which CCA complies satisfactorily. Hence, the use of CCA as a replacement for cement has been investigated over the years. Findings indicate that the partial replacement of cement with CCA decreases compressive strength, thermal conductivity, ultrasonic pulse velocity, and density of the hardened concrete at normal temperatures. Nevertheless, the thermal treatment (calcination) of CCA and extended curing enhances compressive strength owing to higher silica content and extended surface area. Besides, the partial replacement of cement with CCA enhances the insulation properties of mortar, which improves thermal comfort, costs and energy savings in buildings. Hence, the partial replacement of cement with CCA provides an environmentally friendly, low cost, and sustainable approach for valorizing CC residues whilst addressing CO2 emissions in construction.

show abstract

Extraction, Addition and Characterization of Hemicelluloses from Corn Cobs to Development of Paper Properties

Cited by 33 publications

References 16 publications

Biochemical and structural features of diverse bacterial glucuronoyl esterases facilitating recalcitrant biomass conversion

Biochemical and structural features of diverse bacterial glucuronoyl esterases facilitating recalcitrant biomass conversion

Coumarins from the peel of citrus grown in Colombia: composition, elicitation and antifungal activity

Utilization of Corn Cobs Ash as Cementitious and Binary Cementitious Materials in Concrete and Cement-based Composites: A Review

Contact Info

Product

Resources

About