New sources of sugar

In general, the condition of the national sugar industry, at least, has three main problems. First, the low purchasing price of sugar for the production of farmers due to low world market sugar prices. Second, the low productivity of the sugar mills and many are not efficient.

Third, the development of the national sugar industry continues to slump. Sugar production in Indonesia has decreased annually by 2.14% or 44,328.695 tons. While the development of sugar consumption in Indonesia increased from the year 1991/1992 up to the year 2000/2001 amounted to 2.03% or 61,186 tons. Both these factors lead to increase sugar imports trend in Indonesia per year by 11.94% or 116,535.839 tons.

The main source of sugar in Indonesia today are sugarcane (Saccharum officinale), which is now declining productivity caused by climate change in Indonesia that is uncertain. If only rely on the production of sugar from sugarcane, the decline in sugar production will continue to fall and imports of sugar will continue to rise. Thus, the necessary sources other than cane sugar production that can meet the challenges and problems perikliman industrial production situation in Indonesia today.

Caryota mythic Lour. (Fish-tail palm) have a very high content of sucrose in water the flowers, that is equal to 83.5%. Since only use the interest only, Caryota mythic can be managed as plantation crops, like palm oil, which can be harvested continuously over time reproductive tree.

Our hypothesis is flower water (juice) on the mythic Caryota Lour. can be used as an alternative source of sugar cane.

The process to obtain pure sucrose from the tree flower water can be done through a process of water extraction rates, the deposition of dirt, water purification & separation of the sugar content of other compounds, crystallization and subsequent storage to be processed into pure sugar crystals.

The successful introduction of sugar sources that this one will be a new discourse in the development of bio-industry nationwide as well as address challenges need one of the most important food commodity in Indonesia and the world.

New sources of sugar

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The C-Value Paradox

ethics you examine the genomes of various species, you must have thought that a simple organism has a genome that is smaller than the more complex organisms.

Because, you assume that the simpler organisms require less genes than the more complex organisms. This assumption is true, but estimates that the simpler organisms have smaller genomes does not fit the facts.

Take for instance the comparison between humans and amoeba. Humans certainly have more genes than the amoeba, because humans are multicellular organisms that is far more complex than amoeba. It is true, but whether humans also have larger genomes than the amoeba? No.

In fact, humans have 3.3 billion base pairs in the genome, whereas had 200 billion amoeba genome in the genome, which is almost 70 times more than humans! So why the genomes of organisms that are much simpler to have the genome of such magnitude?

Similarly, another example, namely Bony fish and japanese puffer fish, two fish species are species that still have close kinship. Japanese puffer fish has 0.5 billion base pairs in its genome while Bony fish has 300 billion base pairs in its genome, 600 times more than the japanese puffer fish! Why does this happen? What good is excess DNA in the genome of these organisms?

This phenomenon is referred to as the C-Value Paradox, where C refers to the quantity of DNA in the genome of the organism. Excess DNA is not reflecting komplektisitas genetic component, but only in the form of DNA that has no function or encode a functional product in the organism in question.

Most of the DNA is a repetitive segment which consists of transposons and retrotransposons. Transposons or transposable elements also called a segment of DNA that can menginsersikan himself anywhere in the genome either by copying itself through replicative transposition or catalyze the transfer of segments of itself through the mechanism of conservative transposition.

The second mechanism is done by using a transposon transposase enzyme that dikodenya and without going through a phase of RNA. While retrotransposon or retrotransposable elements make the shift or insertion through a phase of RNA.

So in addition to the transcript coding for a reverse trankriptase himself, he also serves as a template to form cDNA and then inserted at certain places in the genome.

In humans, there are two types of retrotransposon, namely Sines (Short interspersed Nuclear Elements) and Lines (Long interspersed Nuclear Elements). LINES 1-6 kbp in length while Sines length: 100 bp-1 kbp. Lines, Sines and other transposons arrange 45% of the total genome of us!

Twenty percent of the total genome is LINES and 13% of the total genome is Sines. One type is called a brother "LINES L1 segments contained in the introns 79% of human genes. These DNA segments are often referred to as junk DNA. Because he did not have any function other than "wishes" to copy itself as much as possible in order to keep survive.

So, the big difference did not reflect the genome of each organism komplektisitas genetic differences, but rather to differences in the ability of each organism to remove or suppress tranposisi of berbagaimacam above junk DNA and other repetitive DNA segments. Or it may be that this repetitive DNA segment actually has a specific function in the genome that could not be detected at this time.

The C-Value Paradox

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Ethanol fermentation by Saccharomyces cerevisiae: The Crabtree Effect

Saccharomyces cerevisiae has long been used in industrial alcohol and alcoholic beverages because it has the ability to ferment glucose into ethanol. The interesting thing is the process of ethanol on yeast fermentation takes place in aerobic conditions.

According to Pasteur, the presence of oxygen will inhibit the fermentation pathway in the yeast cell so that there is a carbon source to be used via the respiratory route. This phenomenon is often referred to as the Pasteur effect (Walker 1998). In cells of prokaryotes and eukaryotes, many found the Pasteur effect, one example is lactic acid fermentation by human muscle cells when deprived of oxygen.

Based on this phenomenon, should the production of ethanol by yeasts occurs in anaerobic conditions. But it turns out, the Pasteur effect in yeast cells was observed in cells that had entered stationary phase (resting), while the production of alcohol occurs when cells are in growth phase (log phase) (Alexander & Jeffries 1990). This makes the Pasteur effect is not a phenomenon that allegedly occurred during the production of ethanol by Saccharomyces cerevisiae.

Herbert Crabtree in 1929 discovered another phenomenon that occurs in tumor cells where the cell is the dominant fermentation pathway occur even in aerobic conditions (Alexander & Jeffries 1990).

In 1948, Swanson and Clifton first to show that this phenomenon occurs in Saccharomyces cerevisiae cells growing and producing ethanol as a fermentation product during a certain amount of glucose contained in the growth medium (Alexander & Jeffries 1990).

This phenomenon was originally called the contre-Pasteur effect before the term used Crabtree effect (de Dekken 1966). Crabtree effect in yeast can be observed when the growth medium containing glucose in concentrations tinggai (above 5 mM) (Walker 1998). Based on the de Dekken (1966),

Crabtree effect does not occur in all yeasts, but only on a few species only, among others Saccahromyces cerevisiae, S. chevalieri, S. italicus, S. oviformis, S. pasteurianus, S. turbidans, S. calsbergensis, Schizosaccharomyces pombe, Debaryomyces globosus, Bretanomyces lambicus, Torulopsis dattila, T. glabrata, and T. colliculosa.

There are three mechanisms that explain the Crabtree effect: 1. catabolite repression; 2. catabolite inactivation, and 3. respiration capacity is limited.

Catabolite repression occurs when glucose, or the initial product of glucose metabolism, suppress the synthesis of various enzymes of respiration (Fietcher et al. 1981). But the detailed mechanisms, such as the compound that gives a signal to suppress the synthesis of these, is still unclear (Walker 1998).

The initial idea catabolite repression triggered by von Meyenberg in 1969 (Alexander & Jeffries 1990) that fosters S. cerevisiae in a medium containing glucose with the method continues culture. The results showed that when low cell concentrations, the metabolic pathways used are respiration, whereas when the cell concentration has reached a critical number, ethanol fermentation occurs.

From these results expected at low cell concentrations, enzymes of respiration was still sufficient to perform respiration path, but when the cell concentration increases, the concentration of enzyme is not increased because the suppressed synthesis by glucose, so the path respiration stopped and replaced by fermentation.

In addition to the repression of enzyme synthesis, a high concentration of sugar will also disrupt the structure of yeast mitochondria, for example loss of membrane in and kristae. However, these structures will be back to normal when respiration path replaces ethanol fermentation (Walker 1998). Changes in the structure will inhibit the Krebs cycle and oxidative phosphorylation takes place in mitochondria.

Catabolite inactivation occurs when glucose disable a key enzyme in the respiratory track, such as fructose 1,6-bifosfatase (FBPase). Inactivation occurs primarily through phosphorylation of the enzyme, followed by protein digestion enzymes in the vacuole (Walker 1998).

The mechanism of inactivation of FBPase in S. cerevisiae begins with the increased concentration of cAMP and FBPase in cells by glucose. The increase in both molecules will trigger cAMP-dependent protein kinase for phosphorylation of FBPase (Francois et al. 1984).

The last mechanism explains the Crabtree effect in yeast is the limited capacity of yeast respiration proposed by Bardford & Hall (1979). Both researchers are conducting research that is similar to von

Meyenberg, but found no evidence of catabolite repression by glucose. Therefore, they argue that the yeast-fermenting yeast that is able to perform aerobic respiration has limited capacity. When present in high concentrations of glucose, glycolysis would run quickly so as to produce a high amount of pyruvat.

But the limitations of these yeasts to use pyruvat in line next respiration (Krebs cycle and oxidative phosphorylation) causes the remaining pyruvat Fermentative revamped into ethanol.

In contrast, the yeast fermentation that is not doing aerobic respiration is considered to have an unlimited capacity to be able to use all pyruvat generated from glycolysis, although the amount of glucose in the medium high (Alexander & Jeffries 1990).

Ethanol fermentation by Saccharomyces cerevisiae: The Crabtree Effect

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Know Amylomyces rouxii

Indonesia and the Asian countries known for food that is produced through fermentation of solid substrate containing starch in large quantities. Examples are cassava and tape sticky tape from Indonesia, chiu-Niang from China, wine from the tape sticky rice from Vietnam, and others.
The fermentation process, using two groups of microorganisms that have different roles, the first group will break down starch into glucose, while the second group will convert glucose into ethanol. Microorganisms are often encountered and is a member of the first group is Amylomyces rouxii (Nout 2007).
A. rouxii is the sole member of the genus Amylomyces. Genus and species was first described by Clamette in 1892.  

Mold is growing rapidly and many produce klamidospora; sporangia not or imperfectly formed, similar to Rhizopus, with a small apofisis; sporangiofor upright with or without rizoid. Synonym A. rouxii is Chlamydomucor oryzae, C. rouxii, C. rouxianus, C. javanicus, and Rhizopus chlamydosporus (Ellis et al. 1976).

  A. Characteristics favorable rouxii in solid substrate fermentation process containing starch is the ability of these fungi to produce enzymes amyloglucosidase, its ability to grow on the substrate raw (uncooked), and inability to sporulating (Nout 2007).

Amyloglucosidase (EC 3.2.1.3), or also commonly known as amylase, is an enzyme that functions break the bond of alpha-1, 4 glycoside on polysaccharide chains. The end result of hydrolysis are dextrins, oligosaccharides, maltose and D-glucose. The process known as saccharification.

One study conducted by Dung et al. (2006) showed that A. rouxii is able to change the 25% starch into glucose after incubation for three days, and to produce amyloglucosidase up to 0.43 U / g.

Although much research on A. rouxii has been done, but the mold is still a mystery, among others, is the natural habitat of A. rouxii, and its evolution. Use of yeast wide tape in Indonesian society the opportunity wide variety A. rouxii which can be sampled in solving the mystery.

Bibliography

    Dung, N.T.P., F.M. Rombouts & M.J.R. Nout. 2006. Functionality of selected strains of molds and yeasts from Vietnamese rice wine starters. Food Microbiology 23: 331-340.
    Ellis, J.J., L.J. Rhodes & C.W. Hasseltine. 1976. The Genus Amylomyces. Mycologia, 68 (1): 131-143.
    Nout, R.M.J. 2007. The colonizing fungus as a food provider. In. Dijksterhuis, J. & R.A. Samson. 2007. Food mycology: A multifaceted approach to fungi and food. CRC Press, Newark: 335-352.

Know Amylomyces rouxii

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