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DECEMBER 2011 VOL 3, NO 8

BIOETHANOL FROM SECOND GENERATION FEEDSTOCK

(LIGNOCELLULOSE BIOMASS)

Ahmad Idi and Shaza Eva Mohamad Faculty of Bioscience and Bioengineering

Universiti Teknologi Malaysia

81310 Skudai Johor

Abstract

Ethanol is a promising alternative fuel which can be produced biologically from a variety of feedstock and

waste. Lignocelluloses biomass (LB) is one of the most abundant biomass and non-food bio-feedstock used in

bioethanol production. Apart from eliminating competition for food and feed, LB is more efficient and

environmentally friendly. It has less farmland requirement and mixture of different crops and agricultural waste

can be used. Bioconversion of LB to ethanol is significantly hindered by the structural and chemical complexity

of biomass, which makes these materials a challenge to be used as feedstock for cellulosic ethanol production.

This paper review the various processes involved in converting lignocelluloses feedstock to bioethanol. Recent

pretreatment methods as well as hydrolysis and the fermentation processes have been extensively reviewed and

illustrated in a simpler form.

Keywords: Lignocelluloses, Pretreatment, Hydrolysis, Fermentation, Lignin, Hemicelluloses, Cellulose

1.0 Introduction

In view of the dependence upon fossil fuel and continuous rising of petroleum price, attention has now been

focused on alternative sources of energy. One of these alternatives is the production of bioethanol. Bioethanol is

a fuel derived from renewable sources of feedstock typically plants such as wheat and sugar beet. Because it is

derived from plants, it has improved 'Lifecycle CO2' performance because the plants used as feedstock take CO2

from the atmosphere as they grown. This means that almost all the CO2 produced by burning the fuel is balanced

by CO2 taken from the air in the first place. The reduced CO2 emissions mean that bioethanol is good for the

environment. In addition it also provide less waste and harmful emissions during production, less pollution to

water, air and land, production of useful by-products and biodegradable fuel. Production of ethanol from

biomass is one of the ways to minimize both environmental pollution and the consumption of crude oil,

Silverstein et al. (2007).

1.1 Lignocelluloses Biomass (LB)

Lignocelluloses biomass is an organic residue which consists of mainly cellulose, lignin and hemicelluloses,

whose basic units are sugars that can be fermented into ethanol or other chemicals. These structural materials

are produce by plants to form the cell walls, leaves, stems, stalks, and woody portions of the plant. The



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carbohydrate polymers (cellulose and hemicelluloses) are tightly bound to the lignin. Up to 80% of the

lignocelluloses are polysaccharide Kaparaju et.al, (2009). Lignocelluloses plant structures also contain a variety

of plant-specific chemicals in the matrix, called extractives (resins, phenolics, and other chemicals), and

minerals (calcium, magnesium, potassium, and others). Examples of LB include: straw, and sugar beet pulp,

alfalfa, corn Stover, crop residues, debarking waste, forage grasses, forest residues, municipal solid waste, paper

mill residue, pomace, scraps & spoilage (fruit & vegetable processing), sawdust, spent grains, spent hops, switch

grass, waste wood chips, wood chips etc. The content of the cellulose, hemicelluloses and lignin varies between

different types of biomass. Table 1 shows the content of cellulose, hemicelluloses and lignin of different types

of LB.

Lignocelluloses materials Cellulose % Hemicelluloses % Lignin %

Hardwood stems 45-50 24-40 18-25

Softwood stems 45-50 25-35 25-35

Nut shells 25-30 25-30 30-40

Corn cobs 45 35 15

Grasses 25-40 35-50 10-30

Paper 85-99 0 0-15

Wheat straw 30 50 15

Sorted refuse 60 20 20

Leaves 15-20 80-85 0

Cotton seed hairs 80-95 5-20 0

Newspapers 40-55 25-40 18-30

Waste papers from chemical pulps 60-70 10-20 5-10

Primary waste water solid 8-15 NAb 24-29

Swine waste 6.0 28 NAb

Solid cattle manure 1.6-4.7 1.4-3.3 2.7-5.7

Coastal Bermuda grass 25 35.7 6.4

Switch grass 45 31.4 12.0

Table I. Content of cellulose, hemicelluloses and lignin in common agricultural residue and waste. Sources: Reshanwala et al (1995), Cheung and Anderson (1997), Boopathy (1998) and Dewes and Hunsche (1998). NA- not available 1.2. Components of lignocelluloses biomass

1.2.1 Cellulose

Cellulose (C6H10O5) n is a polysaccharide consisting of a linear chain of several hundred to over ten thousand β

(1→4) linked D-glucose units. It is the most common form of carbon in biomass, accounting for 40%-60% by

weight depending on the type of biomass Ye sun et al. (2002). It is the structural component of the primary cell

wall of green plants, many forms of algae and the oomycetes. Its crystalline structure makes it resistant to

hydrolysis. The cellulose molecules are organised in elementary fibrils with a diameter of 2-4 nm. These fibrils



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are associated through hydrogen and van der Waals bonds, forming a very rigid, highly crystalline

macromolecular structure.

Figure 1 Structure of cellulose (adapted from Varga E 2003)

1.2.2 Hemicellullose

It is a complex polysaccharide made from a variety of five- and six-carbon sugars. While cellulose is crystalline,

strong, and resistant to hydrolysis, hemicellulose has a random, amorphous structure with little strength, as such

it is easily hydrolyzed by dilute acid or hemicellulase enzymes. It consists of several matrix polysaccharides

(heteropolymers), such as arabinoxylans, present along with cellulose in almost all plant cell wall.

Hemicelluloses differ in three ways from cellulose; by presence of shorter chain, branching of the main

molecule and composition of several sugar units.

Figure 2 Structure of hemicellulose (adapted from Varga E 2003)

1.2.3 Lignin

Lignin is a highly complex, three-dimensional polymer of different phenyl propane units, which are bound

together by ether and carbon-carbon bonds. It is one of the most abundant and important polymeric organic

substance in the plant. Lignin is unusual because of its heterogeneity and lack of a defined primary structure.

Few lignin structures have been known, but generally their structures remain unknown. Although there are great

numbers of microorganisms, which are able to utilise hemicelluloses and cellulose, relatively few strains have

the ability to decompose the lignin effectively Laser et al. (2002).



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Figure 3 .Structure of lignin (source: Adapted from Wikipedia encyclopaedia)

2.0 Production of ethanol from lignocelluloses biomass

Ethanol can be produced from lignocelluloses biomass by the hydrolysis and sugar fermentation processes.

In order to produce sugars from the biomass, the biomass is pre-treated in to reduce the size of the feedstock and

to open up the plant structure. The cellulose and the hemicelluloses portions are broken down (hydrolysed) by

enzymes or dilute acids into glucose or sucrose sugars and then fermented into ethanol. Processing

lignocelluloses to ethanol consists of four major unit operations: 1, Pre-treatment 2, Hydrolysis 3, Fermentation

4, and Separation/Purification.

The figure 4 shows the various processes involve in production of ethanol from lignocelluloses biomass.

Figure 4 Flowchart of bioethanol production from lignocelluloses biomass.

LIGNOCELLULOSE BIOMASS

PRE-TREATMENT ENZYMATIC HYDROLYSIS AND FERMENTATION

DISTLLATION AND EVAPORATION

FILTER AND WASHING WASTE MANAGEMENT

LIGNIN

ETHANOL



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2.1 Pretreatment of lignocelluloses biomass

Pretreatment refers to the solubilisation and separation of one or more components of the biomass

(hemicelluloses, cellulose, and lignin) to make the remaining solid biomass more accessible to further chemical

or biological treatment. This a main processing challenge in the ethanol production from lignocelluloses

biomass. The goal of pre-treatment is to remove lignin and hemicelluloses, reduce cellulose crystallinity and

increase the porosity of the biomass, Sun et al. (2002).

Figure 5.Goal of pre-treatment Adpated from Mosier et al (2005)

During pre-treatment the structure of fibres is altered and the enzyme accessibility to cellulose is enhanced.

Several pre-treatment methods have been proposed and developed for lignocelluloses biomass. But most these

methods fail to meet the basic requirements for efficient pre-treatment. These requirements according

Mohammad et al. (2008) are: (a), Production of reactive cellulosic fibre for enzymatic attack (b),Avoiding

destruction of hemicelluloses and cellulose (c), Avoiding formation of possible inhibitors for hydrolytic

enzymes and fermenting microorganisms (d), Minimizing the energy demand (d), Reducing the cost of size

reduction for feedstock (e), Reducing the cost of material for construction of pre-treatment reactors (f),

Producing less residues, (g),Consumption of little or no chemical and using a cheap chemical.

2.2. Methods of pretreatment of lignocelluloses biomass

2.2.1 Physical method

The main purpose of physical pre-treatment is to reduce the size of the biomass or cellulose crystallinity,

increase the accessible surface area and size of pores, and decrease the crystallinity and degrees of

polymerization of cellulose. This reduction facilitates the access of celluloses to the biomass surface, increasing

the conversion of cellulose. Different types of physical processes such as pyrolysis, grinding, chipping, milling

and irradiation can be used to improve the enzymatic hydrolysis or biodegradability of lignocelluloses biomass.



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Pyrolysis has been studied and found to be an efficient method because cellulose rapidly decomposes when is

treated at high temperature Mohammad et al. (2008).

2.2.2 Liquid Hot Water (LHW) or Thermohydrolysis:

In LHW, pressure is utilized to maintain water in the liquid state at elevated temperatures. Without addition of

acids or production of neutralization wastes, this method is comparable to dilute acid pretreatment Laser et al.

(2002). The method also presents elevated recovery rates of pentoses and does not generate inhibitors Ogier et

al. (1999). This method has been shown to remove up to 80% of the hemicellulose and enhances the enzymatic

digestibility of pretreated biomass materials such as corn fiber and sugarcane bagasse.

2.2.3 Physico-chemical pretreatment

This method combines both chemical and physical processes and it is considered more effective than physical

method Silverstein et al (2007). Physicochemical pretreatment include; steam explosion (autohydrolysis),

ammonia fibre explosion (AFX), carbon dioxide explosion etc. In steam explosion, saturated steam at high

pressure is used to causes autohydrolysis reactions in which part of the hemicelluloses and lignin are converted

into soluble olygomers. This removes most of the hemicelluloses, thus improving the enzymatic digestion. In

AFX the lignocellulosic biomass are exposed to liquid ammonia at moderate temperatures from 25°C to 90°C,

and elevated pressures for10 to 60 min. Holtzapple et al., (1991, 1992). The pressure is explosively released

which disrupts the fibrous structure when the reaction is complete. This appears to be more effective on

agricultural residues and of various herbaceous crops and grasses than on substrates derived from wood

Holtzapple et al. (1991). Mes-Hartree et al. (1988) compared this method and the steam and ammonia

pretreatment and found that steam explosion solubilise the hemicellulose, while AFX did not.

2.2.3.1 Carbon dioxide explosion

This physico-chemical method is similar to stem explosion and AFX. It is based on the hypothesis that

carbon dioxide form carbonic acid increase hydrolysis rate. When Zheng et al. (1998) compared this method

with steam and ammonia explosion for pre-treatment; they found this method was more cost-effective and did

not cause the formation of inhibitory compounds that could occur in steam explosion. But when Dale et al.

(1982) used this method, the yields were relatively low compared to steam or ammonia explosion pretreatment,

but high compared to the enzymatic hydrolysis without pretreatment.

2.2.3.2 Wet oxidation

In this process, the materials are treated with water and air or oxygen at temperatures above 120°C (e.g.

148- 200°C) for a period of e.g. 30 min. Wet oxidation of the hemicelluloses fraction is a balance between

solubilization and degradation. The process is an effective method in separating the cellulosic fraction from

lignin and hemicelluloses. The main reactions in wet oxidation pre-treatment are the formation of acids from

hydrolytic processes, as well as oxidative reactions. All three fractions of lignocellulosic materials are affected

in this process. The hemicelluloses are extensively cleaved to monomeric sugars; the lignins undergo both

cleavage and oxidation; and cellulose is partly degraded. The cellulose becomes highly susceptible to enzymatic

hydrolysis Schurz, J. (1978). Bjerre et al. (1996) combined wet oxidation and alkaline hydrolysis for wheat



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straw pre-treatment. The process resulted in a relatively highly convertible cellulose (85% conversion yield) and

hemicellulose. However, addition of some alkaline agent such as sodium carbonate had only a small effect on

the concentration of solubilized hemicelluloses.

2.2.4 Biological pretreatment

This employs the use of microorganism to treat the lignocelluloses biomass and enhance enzymatic

hydrolysis. The microorganisms usually apply use to degrade lignin and hemicelluloses but very little part of

cellulose, since cellulose is more resistance to microorganism than other parts of lignocelluloses biomass.

Kurakake et.al. (2007) examined the microbial treatment of office paper with Sphingomonas paucimobilis and

Bacillus circulans, and found that treatment with the combined strains improved the enzymatic hydrolysis.

Under optimum conditions, the sugar recovery was enhanced up to 94% for office paper. White-rot fungi are the

most effective Basidiomycetes for biological pretreatment of lignocellulosic materials Sun et al. (2002).

However the rate of hydrolysis in most biological pretreatment processes is very low and the most lignin-

solubilising microorganisms also solubilise or consume cellulose Silverstein et al (2007).

2.2.5 Chemical method

Chemical method employs the use of different chemicals for treatment of lignocelluloses biomass. This

includes alkaline pretreatment, acid pretreatment, ozonolysis, oxidative delignification, organosolv pretreatment

etc.

2.2.5.1 Alkali pretreatment

In this process the removal of the crosslinks of intermolecular ester bonds between xylan hemicelluloses

and other components, for example, lignin and other hemicelluloses increase the porosity of the lignocellulosic

materials McMillan (1994). The effect of this method depends on the on the lignin content of the materials.

Examples of bases use are sodium, potassium, calcium, and ammonium-hydroxide. Using dilute NaOH caused

swelling, leading to an increase in internal surface area, a decrease in the degree of polymerization, a decrease in

crystallinity, and disruption of the lignin structure and separation of structural linkages between lignin and

carbohydrates Varga E. (2003). Pre-treatment with alkali can result in a sharp increase in saccharification, with

manifold yields. Silverstein et al (2007) compared the effectiveness of sulphuric acid, sodium hydroxide,

hydrogen peroxide, and ozone pre-treatments for enzymatic conversion of cotton stalks and found that sodium

hydroxide pretreatment resulted in the highest level of delignification (65% with 2% NaOH in 90 min at 121°C)

and cellulose conversion (60.8%).

2.2.5.2 Organosolv pretreatment

In this process the lignocelluloses biomass is mixed with organic liquid and water then heated to dissolve

the lignin and part of the hemicelluloses, leaving reactive cellulose in the solid phase. A catalyst may be added

either to enhance the delignification process or to reduce the operating temperature. The lignin can be extracted

from the solvent and due to its high purity and low molecular weight; it can then be use for generation of

electricity, process heat, lignin-based adhesives and other products Pan X et al (2005). Organic solvents, such as

methanol, ethanol, acetone, ethylene glycol, etc. are used in this process Chum et al., (1988).The hemicellulose



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and the lignin fraction are both solubilized, while the cellulose remains as a solid. The cellulose fraction from

organosolv pretreatment is susceptible to enzymatic hydrolysis. Chum et al. (1988) reported more than 85%

conversion of cellulose to glucose, following pretreatment at 195°C. However, organic solvents are considered

as inflammable, environmentally harmful, potentially dangerous and therefore need to be replaced.

2.2.5.3 Acid hydrolysis pretreatment

Concentrated HCl and H2SO4 have been used to pretreat lignocellulosic biomass materials. At high temperature

the dilute sulphuric acid pretreatment shows high reaction rates and significantly improve cellulose hydrolysis

Esteghlalian et al. (1997), but at moderate temperature the saccharification yields of cellulose is quite poor

McMillan (1994). Dilute-acid hydrolysis is probably the most commonly apply method among the chemical

pretreatment methods. This method can be performed either in short retention time at high temperature or in a

relatively long retention time at lower temperatures. Emmel et.al. (2003) used this method to treat Eucalyptus

grandis. They used sulphuric acid at short retention time at high temperature and at relatively long retention time

at lower temperature. The best conditions for hemicelluloses recovery were obtained at short retention at high

temperature (210°C for 2 min,) but lower pretreatment temperature was also enough to obtain the highest yield

of cellulose conversion (90%) by enzymatic hydrolysis.

Figure 6. Schematic of (a) dilute acid pretreatment and (b) component –extraction processes. (Adapted from Sai V. et,al (2010))



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2.2.6 Ozonolysis pretreatment

Pretreatment of lignocelluloses biomass with ozone is referred to as “ozonolysis” pre-treatment. This is usually

carried out at room temperature, and does not lead to inhibitory compounds. The major parameters in this

method are moisture content, particle size, and ozone concentration in the gas flow. This method has been

investigated for biogas production to improve digestion of several wastes such as sewage-activated sludge,

Weemaes et al. (2000) and olive mill waste Benitez,et al (1997) and resulted in improvement of the digestion

and reduction in phenolic compounds present in olive mill waste, which are toxic to methanogenic bacteria. The

method does not produce toxic residue and the reaction are carried out at room temperature and pressure. In

addition it effectively removes lignin. However, large amount of ozone is required, making the method very

expensive.

Feed stock Pretreatment Enzymes Hydrolysis

condition

Sugar yield References

Wheat straw 0.75% (v/v)

H2 SO4

Cellulase,

β-glucosidase,

Xylanase, esterase

45OC, pH5.0

72 h

56.5% Saha et al 2005

Wheat straw 2.15 % (v/v)

H2 SO4

Cellulase,

a-glucosidase,

Xylanase

45OC, pH5.0

120 h

67.2% saha et al 2006

Wheat straw Dilute H2 SO4 Cellulose,xylanases,

recombinant

feruloyl esterase

500C, pH4.8

24 h

51.4% Tabka et al,

2006

5 % (w/w)

Cellulose

1-n-butyl-3-

methlimidazolium

chloride

cellulase 50OC, pH4.8

12 h

72% Dadi,et al 2006

Yellow poplar Ethanol

organosolv

pulping process

cellulase 50oC, pH5.0

24 h

Glucose yield

92%

Berlin et al

2006

Spruce Steam Cellulose,

β-glucosidase,

polyethylene glycol

50OC, 48 h Glucose yield

82%

Börjesson et al

2007

Corn stover Steam and 3%

(w/w) SO2

Cellulose,

β-glucosidase,

xylanase

45OC, 72 h Glucose yield

96%, xylose

yield 86%

Öhgren, et al

2007

Olive oil 1% H2 SO4,

190 OC

Cellulose,

β-glucosidase

500C, pH4.8,

72h

36.3% Cara et al 2008

Switch grass 0.1 gg-1

alkali, 190OC

Cellulose,

β-glucosidase

pH 4.8, 50oC 58.7% Hu, Z 2008

TABLE 2. Required pre-treatment and sugar yield in the enzymatic hydrolysis for different feed stocks



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3.0 Hydrolysis

After pretreatment of LB, the cellulose is prepared for hydrolysis, which means, that a molecule is cleaved by

the addition of a water molecule: (C6 H10 O5) n + n H2O → n C6 H12 O6. In this process cellulose is decomposed

into its glucose building blocks. The purer and more refined the cellulose is, the easier it is for the cellulose to

decompose. It occurs either enzymatically by cellulytic enzymes (cellulase) or chemically by sulphuric acid or

other acids.

3.1 Acid hydrolysis

Acid hydrolysis of LB produce xylose from xylan, but the cellulosic and lignin fractions remain unchanged.

Xylan is more susceptible to hydrolysis by mild acid treatment due to its amorphous structure. Cellulose needs

severe treatment conditions because of its crystalline nature. Generally, two main types of acid hydrolysis can

be used:

3.1.1 Dilute acid Hydrolysis: This is done in two stages:

Stage one is performed at low temperatures, to maximize the yield from hemicellulose, as well as to recover the

C5-sugars.

Stage two is done at higher temperatures, to optimize the cellulose portion of the feedstock, as well as to recover

the C6-sugars

3.1.2. Concentrated sulphuric acid

A complete and fast conversion of cellulose to glucose and hemicelluloses to C5-sugars is achieved using

concentrated sulphuric acid. This process needs relatively mild temperatures and pressures as such sugar

degradation is minimized. High sugar recovery efficiency, as well as the potential for cost reduction is the most

significant advantages of this process. The drawback is that concentrated sulphuric or hydrochloric acids are

difficult to work with.



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Figure 7. Schematic demonstration of a dilute acid hydrolysis (2-stage process) and separate fermentation of

pentose and hexose sugars

3.2 Enzymatic hydrolysis

This process occurs by an enzyme called cellulase. The cellulase consists of three consortiums of enzymes:

Endoglucanase (example, endo-1,4-D-glucanohydrolase) which attacks regions of low crystallinity in the

cellulose fiber, creating free chain-ends,

Exoglucanase or cellobiohydrolase, which degrades the molecule further by removing cellobiose units from the

free chain-ends and

β-glucosidase (cellobiase) which hydrolyzes cellobiose to produce glucose. Coughlan et al. (1988).

These are usually derived from the fungus Trichoderma reesei. Hemicelluloses can also be hydrolyzes by

hemicellulase or acid to its monomeric sugars including arabinose, galactose, xylose, and glucose. Using

enzymes for the hydrolysis of lignocelluloses is considered more advantageous than other chemical conversion.

Lignocelluloses biomass

Dilute acid hydrolysis (first stage)

Residual solid biomass fraction

Second stage dilute acid hydrolysis at higher temperature and time

Second stage hydrolysate

Dilute acid hydrolysate (liquid)

Detoxification

Bioethanol fermentation

Recovery of Bioethanol



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It offers low energy requirements, mild operating conditions, higher yields, minimal byproducts formation, and

environmentally friendly processing, Bailey et.al (1993).

Feed stock Hydrolysis Microorganisms Fermentation

condition

Ethanol yield

(gg-1feed

stock)

References

Wheat straw Acid-pretreated

Enzyme hydrolysis

(cellulose,

β-glucosidase,

xylanase, esterase)

Recombinant

E.coli FBR5

35OC, pH6.5, 39 h 0.24 Saha et al

2005

Wheat straw Alkaline H2SO2 -

pretreated

Enzyme hydrolysis

(cellulose,

β-glucosidase,

xylanase)

Recombinant

E.coli FBR5

37oC, pH6.5,48h

37OC, pH6, 48h,

SSF

0.29

0.23

Cara et al

2008

Rice hulls Alkaline H2O2 -

pretreated

Enzyme hydrolysis

(cellulose,

β-glucosidase,

xylanase)

Recombinant

E.coli FBR5

35 oC,pH6.5,48h

35OC,pH6,48h,

SSF

0.21

0.20

Saha cotta

2008

Olive tree

Pruning

0.75 N H2 SO4 P. tannophilus

ATCC32691

30 OC, pH 3.5 0.1 Romero et

al.2007

Sugarcane

bagasse

1.25%(w/w)

H2 SO4

P.tannophilus

DW06

30 OC,pH 5.5,30h 0.1 Cheng et al

2007

Lodgepole

Pine

SO2-catalyzed

steam explosion,

cellulose,

β-glucosidase

S. cerevisiae T1 37 OC,pH5.0, 30 h

SSF

0.24 Ewanick,et

al 2007

Corn stover SO2-catalyzed

steam explosion,

cellulose,

β-glucosidase

baker’s yeast 30OC,pH5.5,

144h, SSF

0.29 Öhgren et

al 2007

Cellulose - Clostridium

Thermocellum

60 OC, pH7.0 0.3 Zertuche,

1982

Barley straw NaOH-pretreated

enzyme hydrolysis

(2% v/v cellulose)

Kluyveromyces

marxianus IMB3

45 OC 0.2 Boyle et al

1997

Table 3. Types of hydrolysis and fermentation conditions for ethanol production from different feed stocks



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4.0 Fermentation process

Fermentation is a process that uses yeast to break down sugar molecules into carbon dioxide gas and ethanol

(ethyl alcohol). Fermentation begins as the growing population of microorganisms produces enzymes to break

two-molecule sugars into single molecule sugars (if needed or capable), and then convert the single molecule

sugars into the commercial chemicals and byproducts. Yields of chemicals approach a limit as the

microorganisms either consume all the fermentable sugars or the products and byproducts of fermentation

inhibit (or kill off) the organism. There are several enzyme-catalysed processes for conversion of lignocelluloses

biomass into ethanol.

4.1 Separate hydrolysis and fermentation (SHF)

When fermenting biomass hydrolyzates involves a sequential process where the hydrolysis of cellulose and the

fermentation are carried out in different units, the configuration is known as separate hydrolysis and

fermentation (SHF). One of the main features of this process is that each step can be performed at its optimal

operating conditions. Reaction time, temperature, pH, enzyme dosage and substrate load are the most important

factor to be consider during this saccharification O´scar et al. (2007). The main advantage of process is the

ability to carry out both the hydrolysis and the fermentation under optimal conditions, e.g. enzymatic hydrolysis

at 40-50°C Varga E (2003). The major disadvantage is that the released sugars inhibit the cellulases. Therefore,

this method is strongly affected by end-product inhibition Alfani et al., (2000).

4.2 Simultaneous saccharification and fermentation (SSF)

When the hydrolysis and fermentation are performed in a single unit, it is known as simultaneous

saccharification and fermentation (SSF). In this process, (the enzyme) cellulases and microorganisms are added

to the same process unit and glucose is immediately consumed by the fermenting microorganism. Thus the

inhibition effect caused by the sugars over the cellulases is neutralized. The main edges of this process over SHF

are higher ethanol yields and less energetic consumption. The drawback in this process is that the optimum

conditions, especially the optimum temperature for the cellulases and the microorganism differ. Stenberg et al.

(2000).

4.3 Simultaneous saccharification and co-fermentation (SSCF)

While there are a variety of yeast and bacteria that will ferment six-carbon sugars (hexose), most cannot easily

ferment five-carbon sugars (pentose), which limits ethanol production from cellulosic biomass. Researchers are

using genetic engineering to design microorganisms that can efficiently ferment both five- and six-carbon sugars

to ethanol at the same time.

The inclusion of the pentose fermentation in the SSF, process is called simultaneous saccharification and co-

fermentation (SSCF. This process represents the hydrolysis and co-fermentation of pentose and hexose sugars in

one vessel. In this process, it is important that both fermenting microorganisms be compatible in terms of

operating pH and temperature. Olsson et al. (1993) reported that the co-culture of P. stipitis and Brettanomyces

clausennii has been utilized for the SSCF of aspen at 38 0C and pH of 4.8 yielding 369 L EtOH per ton of aspen



932


during 48 h batch process. Chandrakant et al. (1998) suggest that a combination of C. shehatae and S. cerevisiae

is suitable for this kind of process.

Biomass ethanol recovery Feedstocks Figure 7. Separate C5 and C6 sugar fermentation SSF and SSCF

Biomass Feedstock ethanol recovery Figure 8. SSF with combined C5 and C6 sugar co-fermentation SSCF

Pre-treatment and hydrolyzate condition

Enzymatic saccharification and C6 fermentation

C5 sugar fermentation

Pre-treatment and hydrolyzate condition

Enzymatic saccharification and co-fermentation



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Börjesson J. R. Peterson, F. Tjerneld, Enzyme Microb. Technol. 2007, 40, 754. DOI:

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Chandrakant, P., Bisaria, V.S., 1998. Simultaneous bioconversion of cellulose and hemicellulose to ethanol.

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Cheng K. K. et al., Biotechnol. Lett. 2007, 29, 1051. DOI: 10.1007/s10529-007-9361-2

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TOURISM DEVELOPMENT & PLANNING IN PROTECTED AREAS, IN A SUSTAINABLE MANNER

(Case study; SABZ KOUH protected area in IRAN`S Chahar Mahal VA Bakhtiari province)

HAMID AMINI

M.A in tourism planning Officer in Iran cultural Heritage, Handicrafts and Tourism Organization,

Address: Tourism section, Haj-o Ziarat Building, Azadi Street, Tehran,Iran MOHSEN MOSLEHI

M.A in tourism planning, Officer in Iran cultural Heritage, Handicrafts and Tourism Organization,

Address: Tourism section, Haj-o Ziarat Building, Azadi Street, Tehran,Iran

Abstract Indigenous and local peoples are a valuable source of knowledge and could greatly contribute to the effective management of protected areas. Seeking that contribution should be a priority for protected area authorities and managers. Under this pilot project it is proposed to develop alternative livelihoods for villages adjoining the protected area through involvement of the community in providing rustic eco lodges for tourists. Whilst this will encourage increased visitation of the area it will also help generate other tourism related small industries and thereby uplift the economy of the community and reduce their dependence on the area. Keywords: Tourism Development & Planning ; Protected areas; Sustainable manner INTRODUCTION Today, the development of tourism industry as a result of ever-increasing development in social life of man, the growth of urbanization and technology has been awsome.Man`s desire to spend his free time has made tourism and sightseeing one of the main needs of human beings. Tourism in addition to engendering income and job opportunities, and increasing economical development and economical variation of a country can have long lasting effect on its social, cultural and environmental variables. Indigenous and Community Conserved Areas (ICCAs) are a globally significant type of managed areas governed by local or indigenous communities for conservation and cultural purposes. Their contributions to biodiversity conservation, sustainable livelihoods, and climate change adaptation are significantly under-studied and documented. Iran as a geographically wide-ranging country enjoys climate variation and a rich civilization with various cultures. From the sand point of abundance and variety of tourist resorts, Iran is situated among 10 countries of the world. However, as a result of many problems and limitations, Iran has not been able to obtain income and revenues in proportion to its full potential. SUSTAINABILITY IN TOURISM Sustainability, for tourism as for other industries, has three interconnected aspects: environmental, socio-cultural, and economic. Sustainability implies permanence, so sustainable tourism includes optimum use of resources, including biological diversity; minimization of ecological, cultural and social; and maximization of benefits to conservation and local communities. It also refers to the management structures that are needed to achieve this. SUSTAINABLE TOURISM IN PROTECTED AREAS IUCN (International union for conservation of Nature) defines a protected area as: “An area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means Emphasis added](IUCN,1994)” There is 98 protected areas in Iran To help improve understanding and promote awareness of protected area purposes, IUCN has developed a six category system of protected areas identified by their primary management objective (IUCN 1994), as shown in Table 2.1 The IUCN protected area management categories system is based upon the primary objectives of management. Table 2.2 shows how an analyze of management objectives can be used to identify the most appropriate category. IUCN (International union for conservation of Nature) defines a protected area as:



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“An area of land and/or sea especially dedicated to the protection and maintenance of biological diversity, and of natural and associated cultural resources, and managed through legal or other effective means Emphasis added](IUCN,1994)” To help improve understanding and promote awareness of protected area purposes, IUCN has developed a six category system of protected areas identified by their primary management objective (IUCN 1994).The IUCN protected area management categories system is based upon the primary objectives of management. Table 2.2 shows how an analyze of management objectives can be used to identify the most appropriate category. There are 98 protected areas in Iran. Sabz kouh protected area covering the total area of 56308 ha is located in the south west of Iran in Chahar Mahal VA Bakhtiari province. It was declared in 1990 as a protected area (which belongs to the V category of IUCN management categories of protected areas). The area is well known as a habitat of different plants and animal species. Although the area does not attract many tourists at present, it has the potential to increase visitation due to the many bird species, wildlife and sceneries that could be spotted. Due to lack of promotion and marketing this area has not gained much popularity as compared to the protected areas around Tehran. Furthermore, one of the biggest challenges faced by the Department of Environment Conservation, managing the reserve is the threat by adjoining communities who depend on it for their livelihood. There are over 20 villages along the boundary of the area. These villagers who depend on contract labor and agriculture for existence are considered as the poorest of the poor. Due to lack of employment opportunities, many young generation prefer to move to big cities finding a job. During a participatory rural appraisal exercise conducted with a few villages, the community requested assistance to get involved in tourism related activities. Resources. Sabz kouh protected area covering the total area of 56308 ha is located in the south west of Iran in Chahar Mahal VA Bakhtiari province. It was declared in 1990 as a protected area (which belongs to the V category of IUCN management categories of protected areas).

Source: Adapted from CREDOC, 2008; and Stolton, 2009.



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Table 2.1 IUCN management categories of protected areas (IUCN 1994)

Categories Description

I Strict Nature Reserve /Wilderness Area: Protected area managed mainly for science or wilderness protection

Ia Strict Nature Reserve :Protected area managed mainly for science

Ib Wilderness Area: Protected area managed mainly for wilderness protection

II National park: Protected area managed mainly for ecosystem protection and recreation

III National Monument: Protected area managed for conservation of specific natural features

IV Habitat/Species Management Area: protected area managed mainly for conservation through management recreation

V Protected Landscape / seascape :Protected area managed mainly for landscape/seascape conservation and recreation

VI Managed Resource Protected Area :Protected area managed mainly for the sustainable use of natural ecosystems



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Table 2.2: Matrix of management objectives and IUCN protected area management categories (IUCN 1994)

Management objectives Ia Ib II III IV V VI

Scientific research 1 3 2 2 2 2 3

Wilderness protection 2 1 2 3 3 - 2

Preservation of species and genetic diversity 1 2 1 1 1 2 1

Maintenance of environment services 2 1 1 - 1 2 1

Protection of specific natural/cultural features - - 2 1 3 1 3

Tourism and recreation - 2 1 1 3 1 3

Education - - 2 2 2 2 3

Sustainable use of resources from natural ecosystems - 3 3 - 2 2 1

Maintenance of cultural/traditional attributes - - - - - 1 2

Key : 1=Primary objective 2=Secondary objective 3= Potentially objective - = not applicable

Iran's protected areas Map



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Defining the problem The area is well known as a habitat of different plants and animal species. Although the area does not attract many tourists at present, it has the potential to increase visitation due to the many bird species, wildlife and sceneries that could be spotted. Due to lack of promotion and marketing this area has not gained much popularity as compared to the protected areas around Tehran. Furthermore, one of the biggest challenges faced by the Department of Environment Conservation, managing the reserve is the threat by adjoining communities who depend on it for their livelihood. There are over 20 villages along the boundary of the area. These villagers who depend on contract labor and agriculture for existence are considered as the poorest of the poor. Due to lack of employment opportunities, many young generation prefer to move to big cities finding a job. During a participatory rural appraisal exercise conducted with a few villages, the community requested assistance to get involved in tourism related activities. Therefore, under this pilot project it is proposed to develop alternative livelihoods for one village adjoining the area through involvement of the community in providing rustic eco lodges for tourists. Whilst this will encourage increased visitation of the area it will also help generate other tourism related small industries and thereby uplift the economy of the community and reduce their dependence on the area. -Involve local communities and tourists in Conserving nvironment, - Bring economic benefits to the communities living inThe protected area (MASHAYEKH tribes) and people Living in the villages adjacent to the protected area and Thereupon poverty alleviation - Giving education to young generations - To provide tourists with a unique natural and cultural Experience - Contribute to the socio-economic development of area Residents and local in habitats through sustainable use of protected area natural

SABZ KOUH SATELITE PLAN



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Sabzkouh Ecotourism potentials Sabz kouh is unique thanks to:

Mountain scenes

Its Flora(scarce species)

Its fauna(wildlife)

Cultural Heritages: Existence of Rural and Nomadic lifestyles side by side

Karun riverside scenes

One of the highest fall of Iran

Pastoral Livelihood

Agricultural livelihood



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And due to:

Herbal medicineAnd Nature friendly herbs(Biodegradable Detergent)

Wild and intact Nature with Wonderful sceneries and landscapes

Crafts,ceremonies,traditions,cloths,…



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Objective: Sustainable tourism development and conservation of protected area instead of preserving merely Goals: -Involve local communities and tourists in Conserving Environment, - Bring economic benefits to the communities living in the protected area (MASHAYEKH tribes) and people living in the villages adjacent to the protected area and thereupon poverty alleviation - Giving education to young generations - To provide tourists with a unique natural and cultural experience - Contribute to the socio-economic development of area residents and local in habitats through sustainable use of protected area natural resources. Benefit

• Increase biodiversity of important habitats and protected plants and animal species. • Increase the number of visitors to the protected area. • Increase the employment local people. • Communities benefits from eco-tourism. • An effort to prevent young migrations toward big cities • Steps toward sustainable development

Activities Table/Matrix

Activities Indicators of success Resources Needed

1.Land use planning for the area

• Revise the province development master plan,

• Technical support by JICA,Tourism department and Environment department

2.Study of background of cultural, historical site to develop tourist access

• Generate the Govt. And local community revenue from protected area entry fee

• Establishing a data base

3. Research on ecological distribution of species

• Protect plant and animal species

Census of fauna and flora

4.Capacity building of protected area staff to receive tourist groups

• Tourist satisfactions • Training in young of host communities

5.Institutional support of rural and nomadic residents

• Collaboration with local Islamic council

• MoU with local authorities and the chef of tribes,

• Persuading Environmental authorities

6. Inadequate of basic equipment (eclogues

• Tourist satisfactions

• Long-term loan voluntary tourist hosts



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,meals, handicrafts)

7. Improve socio-economic status

• Social Sanity, employment, reduction of migration,

• Fund for reviewing experiences of developing countries

Key Stakeholders:

• Iran cultural Heritage, handicrafts and tourism organization, • Environment department • Local communities in villages and nomadic people) • Local authorities

Positively Impacted

Groups Positively impacted How impacted

Staff of protected area Protected area staff will get more time to do their job and build capacity

Visitors/Tourists Visitors will enjoy the beauty of PA ecosystems

local Tourism intermediaries (Travel agents, hotels etc.)

Receiving more tourists

Conservation goals Conservations goals will be developed

Communities Communities will get job, revenue and training opportunities.



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Negatively Impacted

Groups Negatively impacted How impacted

Poachers

Deter poachers from carrying out illegal activities

Morphology of land Over uses of resources,

Scarce species Uproot, game,

Local communities Tourist behavior maybe clashes with local cultural values,

CONCLUSION: Monitoring Continual monitoring is necessary to check whether the applied forms of management having desired effects or not. Evaluation The progress of management will evaluate by the NGOs and local leaders, tourism department, environment department



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References: 1-Soleimanpour, Hadi (2006), Nature-based tourism, Tehran,Iran 2-Eagles, F.J Paul,Stephen F. Macool and Christopher D.Haynes(2002),Sustainable Tourism in Protected Areas,IUCN,United Kingdom 3-Philips Adrian (1998), Economic values of protected areas,IUCN,UNWTO,Spain 4-Zahedi, Shamsosadat (2006).Sustainable Tourism &Ecotourism,Allame tabatabai university ,Tehran,Iran 5--Michael Hughes, TodJones, Margaret Deery, David Wood Liz Fredline, Zachary Whitely and Michael Lockwood (2009), ESTIMATING THE ECONOMIC, SOCIAL AND ENVIRONMENTAL VALUE OF TOURISM TO PROTECTED AREAS, Australia 6-Wade L Hadwen, Angela H Arthington, Paul I Boonington(2008), DETECTING VISITOR IMPACTS IN AND AROUND AQUATIC ECOSYSTEMS WITHIN PROTECTED AREAS, Australia 7-Sally Driml and Char-lee McLennan (2010), HANDBOOK ON MEASURING THE ECONOMIC VALUE OF TOURISM TO NATIONAL PARKS,Australia 8-By David Beyer, Martin Anda, Bernhard Elber, Grant Revell and Fred Spring (2005), BEST PRACTICE MODEL FOR LOW-IMPACT NATURE-BASED SUSTAINABLE TOURISM FACILITIES IN REMOTE AREAS 9-Pamela M. Godde, Martin F. Price, Friedrich M. Zimmermann (2000), Tourism and Development in Mountain Regions 10- IUCN World Commission on Protected Areas. 2000. Foreword by A Phillips &K Miller. Protected areas: Benefits beyond boundaries – WCPA in action . International Union for the Conservation of Nature, Gland, Switzerland . www.iucn.org/themes/WCPA/pubs/pdfs/WCPAInAction.pdf 11-Cho, B.H. 2000, 'Destination', in Encyclopaedia of Tourism. Jafari. J. (ed.). Routledge, New York. pp. 144 -145 12-Adrian Phillip & Javier Beltrán(2000), Indigenous and Traditional Peoples and Protected Areas Principles, Guidelines and Case Studies, World Commission on Protected AreasBest Practice Protected Area Guidelines Series No. 4 13- Paul F. J. Eagles, Stephen F. McCool and Christopher D. Haynes(2002), Sustainable Tourism in Protected Areas Guidelines for Planning and Management 14-Lisa Janishevski, Kieran Noonan-Mooney, Sarat Babu Gidda and Kalemani Jo Mulongoy(2008)Protected Areas in Today’s World: Teir Values and Benefts for the Welfare of the Planet, CBD Technical Series No. 36 15-Lee Thomas and Julie Middleton (2003), Guidelines for Management Planning of Protected Areas, World Commission on Protected Areas (WCPA) 16-Amini Hamid(2004),In the neiborhood of the sky,tourism attractions of chahar mahal va bakhtiari province,ichto org. 17- Darvish sefat Ali Asqar (2007), Atlas of Iranian protected areas, Tehran University 18- Henrick Majnounian(2000),National parks &protected areas, Department of environment of Iran 19-Eskandar firuz(1972),Environment Iran, Department of environment of Iran

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