Biological Pretreatment with White Rot Fungi and Their Co-Culture to Overcome Lignocellulosic Recalcitrance for Improved Enzymatic Digestion

Conversion of lignocellulosic biomass requires pretreatment in order to separate lignin from cellulose. Several methods have been introduced for pretreatment process of lignocellulosic biomass. These are physical, physico-chemical, chemical, as well as biological pretreatment. The following investigation aimed at a biological pretreatment of bagasse using mix-culture of white-rot fungi with the objective to investigate pretreatment effect on the lignin degradation of bagasse with minimum loss of cellulose content. The white-rot fungi involved Phanerochaete crysosporium (Pc), Pleurotus ostreatus (Po), and Trametes versicolor (Tv) on degrading lignin of bagasse with minimal losses of cellulose content 5% (w/v). The culture variation are as follows Po dan Tv (1:1), Po dan Pc (1:1), Pc dan Tv (1:1) and Po, Pc dan Tv (1:1:1) they were inoculated into steamed bagasse and incubated for 1, 2, 3, and 4 weeks respectively. Chemical analysis was done to determine the weight loss, lignin, and alphacellulose content before and after pretreatment. Optimum lignin degradation was achieved after two weeks incubation for each mix-culture. The most effective lignin degradation of mix-culture Po, Pc and Tv (25,26±1,57%) with minimum cellulose loss (17,27±3,76%).Key words : pretreatment, white-rot fungi, mix-culture, baggaseINTISARIKonversi biomassa lignoselulosa membutuhkan proses perlakuan pendahuluan yang bertujuan untuk memisahkan lignin dari selulosa. Beberapa metode telah banyak diketahui untuk proses perlakuan pendahuluan biomassa lignoselulosa, diantaranya perlakuan pendahuluan secara fisika, fisika-kimia, kimia dan biologi. Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan kultur campur jamur pelapuk putih Phanerochaete crysosporium (Pc), Pleurotus ostreatus (Po), dan Trametes versicolor (Tv) terhadap penurunan kadar lignin bagas dengan kehilangan minimal α-selulosa. Inokulum yang digunakan sebesar 5% (w/v) dengan variasi kultur Po dan Tv (1:1), Po dan Pc (1:1), Pc dan Tv (1:1) dan Po, Pc dan Tv (1:1:1). Kultur campur jamur diinokulasikan ke dalam bagas dan diinkubasi masing-masing selama 1, 2, 3, dan 4 minggu. Analisa kimia dilakukan untuk mengetahui kehilangan berat, kadar lignin serta selulosa bagas sebelum dan setelah perlakuan pendahuluan. Hasil penelitian menunjukkan bahwa penurunan optimal kadar lignin bagas dengan kehilangan minimal α-selulosa terjadi pada waktu inkubasi dua minggu untuk setiap variasi kultur campur. Dari empat variasi kultur campur pada waktu inkubasi dua minggu menunjukkan bahwa kehilangan rata-rata lignin bagas tertinggi (325,26±1,57%) dengan kehilangan minimal α-selulosa (17,27±3,76%) terjadi pada kultur campur Pc dan Tv.Kata kunci : perlakuan pendahuluan, jamur pelapuk putih, kultur campur, bagas

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Biological pretreatment of lignocelluloses with white-rot fungi and its applications: A review

BioResources ◽

10.15376/biores.6.4.isroi ◽

2011 ◽

Vol 6 (4) ◽

pp. 5224-5259

Author(s):

Isroi ◽

Ria Millati ◽

Siti Syamsiah ◽

Claes Niklasson ◽

Muhammad Nur Cahyanto ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Manganese Peroxidase ◽

Animal Feed ◽

White Rot Fungi ◽

Ligninolytic Enzymes ◽

White Rot ◽

Chemical Pretreatment ◽

Biological Pretreatment ◽

Factors Affecting ◽

Ruminant Feed

Lignocellulosic carbohydrates, i.e. cellulose and hemicellulose, have abundant potential as feedstock for production of biofuels and chemicals. However, these carbohydrates are generally infiltrated by lignin. Breakdown of the lignin barrier will alter lignocelluloses structures and make the carbohydrates accessible for more efficient bioconversion. White-rot fungi produce ligninolytic enzymes (lignin peroxidase, manganese peroxidase, and laccase) and efficiently mineralise lignin into CO2 and H2O. Biological pretreatment of lignocelluloses using white-rot fungi has been used for decades for ruminant feed, enzymatic hydrolysis, and biopulping. Application of white-rot fungi capabilities can offer environmentally friendly processes for utilising lignocelluloses over physical or chemical pretreatment. This paper reviews white-rot fungi, ligninolytic enzymes, the effect of biological pretreatment on biomass characteristics, and factors affecting biological pretreatment. Application of biological pretreatment for enzymatic hydrolysis, biofuels (bioethanol, biogas and pyrolysis), biopulping, biobleaching, animal feed, and enzymes production are also discussed.

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Biomechanical Pulping of Agave sisalana

Holzforschung ◽

10.1515/hf.2001.007 ◽

2001 ◽

Vol 55 (1) ◽

pp. 42-46

Author(s):

G. Idárraga ◽

J. Ramos ◽

R.A. Young ◽

F. Denes ◽

V. Zuñiga

Keyword(s):

Mechanical Properties ◽

Energy Consumption ◽

Treatment Time ◽

White Rot Fungi ◽

White Rot ◽

White Rot Fungus ◽

Biological Pretreatment ◽

Ceriporiopsis Subvermispora ◽

Agave Sisalana ◽

Strength Improvement

Summary The effect of biological pretreatment of sisal with several white rot fungi on the energy consumption in refining and on the mechanical properties of the pulps was evaluated in this investigation. Improvements were realized in all the mechanical properties (22–66 %) and a reduction in the energy consumption of > 39% was realized for the treated pulps with the different fungi. The best strength improvement and energy reduction results overall were obtained with the white-rot fungus, Ceriporiopsis subvermispora. The incubation time was optimized for this fungus with the optimum mechanical properties obtained with a two week treatment time.

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