Proses-Karbohidrat -2
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Transcript of Proses-Karbohidrat -2
PROSES KONVERSI KIMIAWI PADA BAHAN YANG MENGANDUNG
KARBOHIDRAT
TEKNOLOGI PROSES
BahanMentah
Pengubahan Kimiawi/
biokimiawi,atau Fisik
Produk
Daftar Konversi Kimiawi Utama1. Asetilasi
2. Alkoholisis
3. Alkilasi
4. Aminasi dengan
reduksi
5. Aminolisis
6. Aromatisasi atau
Siklisasi
7. Kalsinasi
8. Karboksilasi
9. Penyabunan
10. Pembakaran
11. Kondensasi
12. Dehidrasi
13. Dinitrifikasi
14. Dekomposisi ganda
15. Elektrolisis
16. Esterifikasi
17. Fermentasi
18. Reaksi Friedel -
Crafts
19. Halogenasi
20. Hidroformilasi
21. Hidrogenasi
22. Dehidrogenasi
23. Hidrogenolisis
24. Hidrolisis
25. Hidrasi.
26. Pertukaran ion
27. Isomerisasi
28. Netralisasi
29. Nitrasi
30. Oksidasi
31. Polimerisasi
32. Pirolisis
33. Reduksi
34. Pembentukan
Silikat
35. Sulfonasi
36. Dsb.
Karbohidrat (Hydrates of carbon), sebagian mempunyai rumus empiris : Cn(H2O)n
n = 3 - ribuan
Penggolongan Karbohidrat :1. Monosakarida
(n=5 Pentosa, n=6 heksosa, n=7 heptaosa)Paling sederhana : 3 C gliseraldehida
dihidroksiaseton
2. Oligosakarida (2-10 unit monosakarida)
3. Polisakarida (> 10 unit monosakarida)Homopolisakarida, Heteropolisakarida
Karbohidrat sumber energi utama bagi aktivitas
manusia selain protein dan lemak
Indonesia : 80-90% sumber energi dari karbohidrat
pangan pokok beras, jagung, sagu
USA : 46% karbohidrat, 42% lemak, 12% protein
Sumber karbohidratSumber karbohidrat
-Sumber Nabati : Hasil fotosintesa
-Sumber Hewani : biosintesis glikogen & sintesa
kimiawi lain
Konversi Kimiawi pada karbohidrat
Hidrolisis DehidrasiXilan Xilosa furfural Asam H2SO4
Glukosa komersial dihasilkan dari proses hidrolisis pati(C6H10O5)n + n H2O n C6H12O6
Hidrolisis Isomerisasi Pati Glukosa Fruktosa
C6H12O6 + C6H12O6 C12H22O11 + H2O monosakarida monosakarida disakarida air
Sukrosa (Saccharose)
Sumber : tebu (Saccharum officinarum) dan bit (Beta vulgaris)
Gula invert : hasil reaksi hidrolisis sukrosa menghasilkan campuran glukosa dan fruktosa, dikatalisis oleh enzim invertase atau asam
Sukrosa Inversi Gula invert-dekstrorotari - levorotari- + 66.5o - - 19.8o
Fruktosa + melibiosa
Rafinosa
Galaktosa + sukrosa
Asam lemah
maltase
Hidrolisis Disakarida + air monosakarida
Pengaruh panasGula dipanaskan karamelisasi
Tingkat kemanisan relatif gula
Gula Kemanisan relatif (%)
Fruktosa 170
Gula invert 130
Sukrosa 100
Glukosa 75
Maltosa 30
Galaktosa 30
Laktosa 15
Tingkat kemanisan berbagai sugar alcohol
Pemanis Tingkat kemanisan (%)[sukrosa 100%]
Sumber bahan baku/ proses
Manitol 40-50 Hidrogenasi fruktosa
Sorbitol 40-50 Hidrogenasi glukosa
Xilitol 100 Hidrogenasi xilosa
Arabinitol ~100 Hidrogenasi arabinosa
Isomaltitol 50 Hidrogenasi isomaltulosa
Laktitol 30 Hidrogenasi laktosa
Maltitol ~90 Hidrogenasi maltosa
L-sorbosa 60-80 Proses fermentasi glukosa
D-xilosa 50 Hidrolisis hemiselulosa
Laktulosa ~60 Isomerisasi laktosa
Tingkat kemanisan relatif berbagai pemanis sintetis
Pemanis Kemanisan relatif (b/b.)
Sukrosa 1
Sodium siklamat 15-31
Dulcin (p-etoksifenilurea) 70-350
Saccharine 240-350
L-aspartil-L-fenilalanin metil ester
250
1-n-propoksi-2-amino-4-nitrobenzen
4100
Tingkat kemanisan relatif pemanis alami
Pemanis alami SumberKemanisan
relatif (sukrosa 1)
Monellin Pulp dari Dioscorephyllum cumminsii
3000
Thaumatins Buah Thaumatococcus daniellii
2000
Miraculin Buah Synsepalum dulcificum
Steviosida Daun Stevia rebaudiana 300
Osladin Polypodium vulgare 3000
Phylloducin Hydragea macrophylla 200-300
Glycyrrhizin Akar Glycyrrhiza glabra 50
Bahan Hasil Pertanian sumber Karbohidrat
Biji-bijian sumber pati : gandum, cantel, sorgum, jali-jali, jagung, jawawut, dll
Wheat
Rye
Barley
Oats
Serealia
Maize
Sorgum
Spelt
Greencorn
Buckwheat
Ekstraksi Pati dari sumber biji-bijian
Bahan Baku
Pembersihan Penggilingan Perendaman
Air
Penapisan
Air Rendaman Air
Penyaringan
Ampas
Suspensi Pati
Pengendapan
Supernatan
Endapan Pati
Pengeringan Penggilingan Pati
Diagram blok garis besar pengolahan produk-produk yang berasal dari jagung (Corn Products Refining Corp. and Dorr-Oliver)
Jagung
Pembersihan
PerendamanAir SO2
Air perendaman encer
Suspensi pati Suspensi pati-serat
Separasi hidrosiklon lembaga
Suspensi lembaga
Ekstraksi minyak
Minyak jagung
Ampas
Evaporasi
Pakan hewan
Penggilingan , pencucian dan penyaringan
Suspensi pati-gluten
Pemisahan
Gluten Pati
A
Diagram blok garis besar pengolahan produk-produk yang berasal dari jagung (Corn Products Refining Corp. and Dorr-Oliver) (lanjutan)
A
Hidrosiklon pencuci pati
Perlakuan kimiawi
Filtrasi dan pengeringan
Produk pati Pemasakan
Dekstrin dan gum
Pati bersih
Konversi pati dengan asam enzim netralisasi
Filtrasi dan pemurnian
Evaporasi dan pemurnian
Kristalisasi
Sirup jagung Sentrifugasi dan pengeringan
Dekstrosa gula dan sirup jagung
Diagram alir garis besar pengolahan produk-produk yang berasal dari jagung (Corn Products Refining Corp. and Dorr-Oliver di dalam Shreve dan Brink, 1984)
Diagram blok proses pembuatan bir
GrindingMalt barley Malt adjunct (beras/jagung)
Penimbangan
Pemasakan bertekanan
Air panas dan dingin
Uap
Pemasakan di ketel bir
Hop
Pendinginan
Penumbuhan awalKhamir
Fermentasi (40-58 oF)
Pendinginan dan penyimpanan di tangki timbun (32 oF)
Filtrasi
Penyimpanan di tangki
CO2
Kompresi
A
A
Bir Pembotolan
Penutupan, pasteurisasi dan
pelabelan
Bir dalam botol / kaleng
Diagram alir proses pembuatan bir (Shreve dan Brink, 1984)
Kacang-kacangan sumber karbohidrat
Ganyong Kimpul Talas
Gembili Uwi Suweg
Umbi-umbian sumber pati : ganyong, gembili, uwi, suweg, kentang, talas, kimpul, dll
Ekstraksi Pati Ubi Kayu
Bahan Baku Pengupasan dan pencucian
Pemarutan Pengepresan
Suspensi patiPengendapanEndapanPengeringan
Penggilingan Pati
Air Cucian
Air Air
Ampas
Air
Ekstraksi Pati dari Sumber Batang
Bahan Baku
Pembersihan Pemotongan Pembelahan Penokokan
Air
EmpulurPemerasan
Ampas dan
Kotoran
Suspensi Pati
Penyaringan
Ampas dan
Kotoran
Suspensi Pati
Pengendapan Endapan Pati
Pengeringan Pati
InulinLinear polilfruktan berikatan dengan ikatan -2,1 glikosidik
Sumber Inulin : Jerusalem Artichoke, umbi dahlia, akar chicory, dan dandelion
Sifat : - sedikit larut dalam air panas - mudah dihidrolisis oleh asam - Tidak berfungsi sebagai sumber nutrisi - Sumber HFS (dengan inulinase)
Proses Produksi Pati Termodifikasi (Food Thickener)
A
Pati cassava 50 %
Pengadukan pada T= 45 oC
Sodium Sulfat
Pengadukan pada t=24 jamT= 45 oC
Sodium Hidroksid dan propilen oksid
Netralisasi dengan HCl
Sentrifuse
ResiduPencucian
Sentrifuse
Supernatan
Endapan
Proses Produksi Pati Termodifikasi (Food Thickener)
Pengadukan
Penambahan Posporous oksiklorid dan diaduk 30 mnt
Penambahan sodium hidroksid sampai pH 11-11,8
SupernatanSupernatan
Air
Netralisasi dengan HCl
A
Pencucian 2 kali dengan air
A
Proses Produksi Pati Termodifikasi (Food Thickener)
Penggilingan
Pengeringan
A
Endapan Supernatan
Pati termodifikasi
Penggilingan
Penyaringan
Sentrifuse
Produk Hidrolisis Pati DE Aplikasi
Maltodekstrin 3-20 Stabilizer, thickener, filler,lem dan pasta
Sirup Maltosa 48-63 Permen keras, mencegah higroskopis, fermentasi
Sirup Glukosa 96-98 Soft drink, fermentasi
Sirup Fruktosa - Industri pengalengan, soft drink, produk susu
Sirup Campuran 42-63 Soft drink, bahan baku industri pangan
Hidrolisis Pati
1. Enzimatis
2. Hidrolisis Asam
Proses produksi HFCS (High Fructose Corn Syrup)
Proses Produksi Dekstrin
Hidrolisat parsial dari pati, hasil kerja enzim, asam dan panasSenyawa antara dalam sintesis pati
Sifat dekstrin :
- Larut dalam air, tidak larut dalam alkohol- Mempunyai gugus karbonil bebas senyawa pereduksi- Memberikan respon warna terhadap Iodine berbeda
Jenis Pati/Dekstrin Respon warna terhadap iodin
Amilosa Biru tua, hitam
Amilodekstrin Biru
Erithrodekstrin Merah
Achrodekstrin Tidak berwarna
Amilopektin Merah-violet
Sumber gula : tebu, bit, aren, nipah, dll
Diagram blok pembuatan gula tebu kasar
Tebu
PenggilinganHasil samping :
Bagase
Boiler
Jus tebu
Pencampuran
Kapur
Filtrasi 1
Filtrat keruh
Filtrasi 2
Filtrat jernih
Pemanasan dan evaporasi
A
A
Filtrat kental
Kristalisasi
Kristal bibit
Sentrifugasi
Gula kasar mutu tinggi
Molase akhir
Diagram alir pembuatan gula tebu mentah (Shreve dan Brink, 1984)
Diagram blok pembuatan gula tebu murni
Gula kasar
PencairanAir
FiltrasiAdsorban Air pencuci panas
Cairan dan sirup
Pemvakuman
KristalisasiPenghalusan dan
aerasiPenyaringan
Pengeringan hingga membentuk granular Gula putih
Gula halus
kadar gula tinggi
Kadar gula rendah
Pencampuran Molase akhir
Diagram alir pembuatan gula tebu murni (Shreve dan Brink, 1984)
Diagram blok proses dalam industri alkohol
Molase
Penimbangan
PengenceranAir
Sterilisasi molase
Penyiapan kultur khamir
(NH4)2SO4
H2SO4
UapFermentasi
Bir
Pembuangan CO2 Air CO2
Penukar panas
Destilasi Slop
A
A
PemurnianH2O
Uap
Dephlegmator
Kondensor
Aldehid
Separator Minyak fusel
Kolom pemisah
H2O
Dephlegmator
Kondensor
Alkohol 95%
Diagram alir proses dalam industri alkohol (Shreve dan Brink, 1984)
BIOETANOL
Substitusi bahan bakar bensin Rumus kimia (C2H5OH) Penampakan : cairan tidak berwarna, jernih,
mudah menguap, berbau khas alkohol, berfase cair pada suhu kamar, mudah terbakar dan dapat dibuat dari biomassa maupun fraksi minyak bumi
Bahan baku bioetanol
Bahan berpati
Sugar contain material
Cellulose contain material
Ketela pohon Sagu Sorghum Jagung Kentang manis
Tebu Nira nipah Nira sorghum manis Nira aren Molase
Kayu Jerami Batang pisang Bagas tebu
Bahan baku berpotensi lainnya
PROSES PRODUKSI
Prinsip : Fermentasi dengan bantuan mikoorganisme dimana bahan baku (gula sederhana/glukosa) diubah menjadi etanol
Produksi Bioetanol
Bahan berpati
Hidrolisis (Asam/enzim)
Larutan Gula
Fermentasi
Bioetanol
Produksi bioetanol dari pati sagu
Hidrolisis EnzimPati
Pembuatan suspensi pati 30% dalam CaCO3 200 ppm
Larutan Gula
Gelatinisasi (105oC, 5 menit)
-amilase1.75 U/g pati
Pengaturan pH 5.2
Likuifikasi95oC, 180 menit
Sakarifikasi(60oC, pH 4.5, 72 jam)
Glukoamilase0.3 U/g pati
Konversi pati menjadi gula
Hidrolisis AsamPati Sagu
Pembuatan suspensi pati 30% dalam air
Larutan Gula
Pengaturan pH 2 dengan HCL 0.1%
Penetralan dengan NaOH 1 N
Hidrolisis121oC, 60 menit
Hidrolisis asam skala pabrik
Konversi pati menjadi gula
Fermentasi Larutan Gula Menjadi Etanol
Larutan gula 25-35 Brix
Penambahan nutrisi dan pengaturan PH 3.9-4
Bioetanol
Fermentasi 7 hari, suhu 25-30oC
Starter 10-15% (v/v)
Pasteurisasi85oC, 5 menit
Destilasi
Fermentasi bioetanol skala pabrik
Fermentasi skala lab
Fermentasi Larutan Gula Menjadi Etanol
Broth
Etanol
Fermentor
Nutrisi yang ditambahkan :
• (NH4)2SO4 5.19 g/l
• KH2PO4 1.53 g/l
• MgSO4 0.55 g/l
Sumber nutrisi lainnya :
• NPK 0.04% (b/v)
• ZA 0.15% (b/v)
NUTRISI STARTER
Inokulum :
1. Ragi Komersial
2. Biakan Saccharomyces
Biakan S.cerevisiaeRagi komersial
Persiapan Starter
Inokulum
Pemindahan ke medium GYE steril 1 g ragi komersial/20 ml1 jarum ose biakan/20 ml
Starter
InkubasiRagi komersial : 24 jamBiakan murni : 48 jam
Destilasi
Bertujuan untuk pemisahan etanol dari komponen lain (terutama air)
Destilasi menghasilkan etanol dengan kadar alkohol 95%.
Perlu dilakukan pengeringan (dehidrasi)
Destilasi skala pabrik
Molecular Sieve
• Bahan yang digunakan sebagai absorben untuk gas dan cairan
• Dapat menyerap air hingga 22% dari berat bahan adsorben
• Molecular sieve : alumunium silikat, zeolit, carbon aktif, clays
zeolit
PSA
Molecular sieve plant Molecular sieve skala kecil
Bahan baku
Slurry tank Liquifiying tank Saccharifiying tank
Clarifiying tankFilter press
Filter tank Evaporating tank
Fermentor
Etanol
PILOT PLANT BIOETANOL-IPB
Bahan berlignoselulosa : serat, kayu, tongkol jagung, tkks, pelepah, dll
Lignoselulosa : bahan hasil pertanian yang mengandung (1) Lignin, (2) Hemiselulosa, (3) selulosa
Fungsi Lignin- Mengikat sel-sel tanaman satu dan lainnya- Sebagai pengisi dinding sel sehingga tanaman menjadi menjadi keras, teguh dan kaku
Hemiselulosa, terdiri atas :(1) Glukomanan Monomer : -D-glukopiranosa, -D-manopiranosa(2) Arabinogalaktan
Monomer : -D-galaktopiranosa. -D-glukopiranosa(3) Xilan
Monomer : -D-xilopiranosa, ikatan -1,4 glikosidik
Selulosa Senyawa utama dalam struktur jaringan tanamanDalam dinding sel bergabung dengan lignin dan hemiselulosa
Sumber selulosa berbeda kekuatan dan ketahanannyaCo. Serat kayu, flax, kapas (>90% selulosa)
Kapas
benang
Pulp & kertas kayu
Dietary fiber
Xilitol Termasuk gula alkohol dengan lima karbon (1,2,3,4,5
pentahydroxy pentane) dengan formulasi molekul C5H12O5.
Pemanis rendah kalori (4 kal/g), indeks glukemik jauh lebih rendah tidak meningkatkan gula darah dan metabolisme tanpa insulin aman untuk penderita diabetes
Proses pembuatan xilitol
Rumput Laut sumber Karbohidrat
Rumput laut bernilai ekonomis
Struktur Kimiawi Polisakarida(1) Homopolisarida(2) Heteropolisakarida(3) Senyawa konjugasi : gabungan dengan lipid & protein
Polisakarida dalam bahan pangan(1) Pati (pati kasar, pregelatinisasi, pati termodifikasi)(2) Selulosa dan turunan selulosa(3) Ekstrak rumput laut (alginat, karagenan, agar, furcellaran)(4) Gum dan lendir dari tanaman (arabik, karaya, tragacanth)(5) Gum biji-bijian (locust bean dan guar)(6) Ekstrak tanaman (pektin)(7) Mikrobial gum (xanthan)
Klasifikasi Hidrokoloid Alami dari Tanaman
(1) Polisakarida Anionik dari Rumput LautCo. Agar, alginat, karagenan
(2) Polisakarida Anionik dari Exudate Co. Arabic, ghatti, karaya, tragacanth(3) Polisakarida non-ionik dari bijian
Co. Guar gum, locust bean gum,(4) Polisakarida anionik hasil fermentasi
Co. Xantan, dekstran, gellan gum
Produk Hidrokoloid Alami
Klasifikasi Hidrokoloid Alami dari Tanaman
Polisakarida Komponen Penyusun SumberAgar Poligalaktosa Rumput laut alga merah
GracalariaAlginat Asam manuronat &
guluronatAlga coklat Laminaria
Karagenan Poligalaktosa ester asam sulfat
Alga merah Chondus crispus
Gum arabic L-arabinosa, L-rhamnosa, D-galaktosa, asam D-glucoronat
Exudate tanaman Acacia Senegal
Gum tragacanth Campuran polisakarida asam, unit asam galakturonat, D-galaktosa, L-fucose, D-xylose, L-arabinosa
Exudate tanaman Astragalus
Locust bean gum
Rantai manosa, dan unit galaktosa
Locust bean (carob bean) dari Ceratonia siliquia
Xantan Rantai utama selulosa, rantai cabang galaktosa
Mikroba Xanthomonas campestris
Carbohydrates Chemical Reaction
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
Carbohydrates
Monosaccharides Disaccharides amd polysaccharides
Ketoses Aldoses Reducing (hemiacetals) Non-reducing (acetals)
Hexoses PentosesA b ility to re a c t w ith A g 2 O + N H 3 + H 2 O
E x a m p le s :
CHOOH
OH
OH
OH
OH
OH
OH
OH
O
OH** ** *
*
A n a ld o h e x o se , 2 4 = 1 6 s t e re o iso m e rs A k e to p e n to se , 2 2 = 4 s t e re o iso m e rs
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
CH2OH
H O
H OH
D-glyceraldehyde
CH2OH
H O
OH H
L-glyceraldehyde
D-key L-key
Every monosaccharide belongs to either D- or L-type
L- and D-monosacharides are enantiomers
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
CH2OH
O
H OH
OH H
H OH
H OH
H
O
OHH
HH
OHOH
H OH
HCH2OH
Open form of glucose
OH
O
H OH
OH H
H OH
HOH2C H
H
OHO
H
OH
OH
H
H
OH
CH2OH
H
H
H + o r O H -
Not Fischer projections!
OHH
H
OH
OH
H
H
OH
CH2OH
H
O
O
HH
HH
OHOH
H OH
OHCH2OH
H + o r O H -
Haworth projections
-Glucose (-D-glucopyranose)
Epimers
-Glucose (-D-glucopyranose)
All cyclic forms of monosaccharides are cyclic hemiacetals. The cycle are preferred forms and contain either 6 atoms (pyranoses) or 5 atoms (furanoses)
CH2OH
H O
H OH
H OH
H OH
Open form of ribose
-Ribose (-D-Ribofuranose)
OH
H O
H OH
H OH
HOH2C H
H + o r O H - H + o r O H -
OHH
O
H
OH
H
OH
CH2OH
HOH
O
H
H
OH
H
OH
CH2OH
H
O H
OHH
OH
H
OH
CH2OH
H
O OH
HH
OH
H
OH
CH2OH
H
-Ribose (-D-Ribofuranose)
Example 2: Cyclization of ribose
CH2OH
CH2OH
O
OH H
H OH
H OH
Open form of fructose
-Fructose (-D-fructofuranose)
H + o r O H - H + o r O H -
-Fructose (-D-fructofuranose)
OH
CH2OH
O
OH H
H OH
HOH2C HOH
CH2OH
O
OH
H
H
OH
CH2OH
HOH
O
CH2OH
OH
H
H
OH
CH2OH
H
O CH2OH
OHH
OH
OH
H
CH2OH
H
O
CH2OHH
OH
OH
H
CH2OH
H
OH
Example 3: Cyclization of fructose
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
CH2OH
O
H OH
OH H
H OH
H OH
H
Glucose
C a (O H ) 2
H 2 O
CH2OH
O
H OH
OH H
H OH
H OH
H
CH2OH
O
OH H
OH H
H OH
H OH
H CH2OH
CH2OH
O
OH H
H OH
H OH
+ +
CH2OH
OH
OH
OH H
H OH
H OH
H
Enolization
Recovered glucose, 67% Mannose, 2% Fructose, 30%
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
O
OHH
HH
OHOH
H OH
HCH2OH
A glycoside hydroxyl
-D -G lu c o p yra n o se (a h e m ia c e ta l)
O
OH
HH
OHOH
H OH
HCH2OH
CH3
M e th yl-D -g lu c o p yra n o s id e (a g lyc o s id e (a n a c e ta l)
H C l, C H 3 O H
OC
+H
HH
OHOH
H OH
H
CH2OHO
HH
HH
OHOH
H OH
O+CH2OH
CH3
HO
O+H
HH
OHOH
H OH
HCH2OH
HH
H+
OH CH3
+
+
O
HH
HH
OHOH
H OH
OCH2OH CH3
O
O+
HH
H
OHOH
H OH
HCH2OH
CH3
H
O
H
CH3H
OHH
NH2
O
H
OH
OH
OH
H3CO
O
O
O
CH2OH
H
A n o th e r e x a m p le o f a g lyc o s id e :
D o x o ru b ic in (a n a n t ic a n c e r d ru g )
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
O
OHHH
OH
HH
OH OH
H
OH
(C H 3 O ) 2 S O 2
N a O H
O
OCH3
HH
H3CO
HH
H3CO OCH3
H
OCH3O
HHH
H3CO
HH
OCH3OCH3
OCH3
OCH3
+
1. Alkylation at the glycoside position (see the previous slide)
2. Complete alkylation
3. Complete acylation
O
OHHH
OH
HH
OH OH
H
OH
O
OAcHH
AcO
HH
AcO OAc
H
OAcO
HHH
AcO
HH
OAcOAc
OAc
OAc
+A c e t ic a n h yd r id e
P y
CH2OH
O
H OH
OH H
H OH
H OH
HCOOH
CH2OH
H OH
OH H
H OH
H OH
B r 2 , H 2 O
C a C O 3
Glucose Gluconic acid
4. Oxidation to aldonic acids
5. Oxidation to aldaric acids
CH2OH
O
H OH
OH H
H OH
H OH
HCOOH
COOH
H OH
OH H
H OH
H OH
Glucose Glucaric acid
H N O 3 , H 2 O
6 0 oC
6. Reduction to alditols
7. Oxidation by the Tolence reagent (Ag2O, NH3, H2O), producing Ag (a silver mirror reaction).
Because of the basic conditions, the reaction produces a messy mixture ofcarbohydrate-based ammonium salts (mostly ammonium gluconate).
CH2OH
O
H OH
OH H
H OH
H OH
HCH2OH
CH2OH
H OH
OH H
H OH
H OH
Glucose Sorbitol
N a B H 4 , H 2 O
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
CH2OH
H O
OH H
H OH
H OH
Arabinose
CH2OH
NH
H OH
OH H
H OH
H OH
H
H C N
O H - +
29% 51%
CH2OH
O
H OH
OH H
H OH
H OH
H
Glucose
H 2 O , H +
H 2 , P d / B a S O 4 ,P re ssu re
Gluconitrile Manonitrile
CN
CH2OH
H OH
OH H
H OH
H OH
CN
CH2OH
OH H
OH H
H OH
H OH
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
Disaccharides and polysaccharides are composed from two or more cyclicmonosaccharides. If the saccharide contains at least one semi-acetal group, it is a reducing sugar due to the equilibrium with the open form, whichactually reacts with the Tolence reagent. Saccharides-acetales do not react withTolence reagent, because they do not equilibrate with the open form in the alkaline conditions.
Examples:
OH
HOH
HOH
H OH
OH
OHO
HH
H
OHOH
H OH
OH
OHH + , H 2 O
+
-L a c to se(-D -g a la c to p yra n o s id o --D -g lu c o p yra n o se )
Galactose Glucose
O
OHH
HOH
H OH
H
OHHO
HH
HOH
HOH
H OH
O
OH
A semi-acetal fragment
A reducing sugar
O
HH
H
OHOH
H OH
OH
OHH + , H 2 O
Glucose
A non-reducing sugar
+O
OHH
OH
OH
HH
OH OH
Fructose
O
H
OH
OH
HH
OH
OH
O
OH
H
OHOH
H OH
H
OHH
S u c ro se (-D -g lu c o p yra n o s id o --D -fru c to fu ra n o s id e )
Polysaccharides
OH
HH
OHOH
H OH
OH
OHH + , H 2 O
Glucose
+O
OHH
HOH
H OH
H
OHHO
HH
H
OHOH
H OH
O
OHH
C e llu b io se (b u ilt fro m - fra g m e n ts o f g lu c o se )
O
HH
H
OHOH
H OH
OH
OHH + , H 2 O
Glucose
+
A m ilo se is a w a te r u n so lu b le c o m p o n e n t o f s t a rc h , b u ilt fro m - fra g m e n t s o f g lu c o se w ith a lm o s t n o b ra n c h in g
O
O
HH
OHOH
H OH
OHH O
OHH
HOH
H OH
H
OHHH
A m ilo p e c t in is a w a te r so lu b le c o m p o n e n t o f s t a rc h , b u ilt fro m - fra g m e n t s o f g lu c o se w ith h ig h e x te n t o f b ra n c h in g
Site of branching
Cellulose is a water unsoluble polymer, built from -fragments of glucose with no branching
Maltose
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
N
N
N
N
N
N
HPyrimidine
Purine
N
N
OH
OH
NH
N
O
O
HUracil (U)
The point of attachment to RNA
N
N
OH
OH
H3CNH
N
O
O
H
H3C
Thymine (T)The point of attachment to DNA
NH
N
O
O
H
F
Fluorouracil (an anticancer drug)
N
N
NH2
OH
N
N
NH2
O
HCytosin (C)
The point of attachment to DNA or RNA
N
N
N
N
H
NH2
Adenine (A)
The point of attachment to DNA or RNA
N
N
N
N
H
OH
NH2
Guanine (G)
The point of attachment to DNA or RNA
NH
N
N
N
H
O
NH2
Complimentarity of pyrimidine and purine bases
NN
NNH
N H
H
AD
A
N
N
O
O
H
CH3
H
T
A
A
D
A
D
G C
D
A
A
D
NN
N
N
H
O
N
H
H
H
NN
N
O H
HH
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
Nucleosides are glycosides, formed by one of five above listed bases with either -D-ribose or -D-2'-deoxyribose
Examples:
O OH
HH
OH
H
OH
H
OHO OH
HH
H
H
OH
H
OH
OH
OH
H
OH
H
OH
N
N
N
N
NH2
H
Adenosine2'-Deoxythymidine
OH
H
H
OH
H
OH
H
NH
N
O
O
H3C
Nucleotides are esters of nucleosides and phosphoric acid
Examples:
OH
OH
H
OH
H
O
N
N
N
N
NH2
H
PO
OH
OH
Adenosine-5'-phosphate 2'-Deoxythymidine-5'-phosphate
OH
H
H
OH
H
O
H
NH
N
O
O
H3CPO
OH
OH
OH
OH
H
OH
H
O
N
N
N
N
NH2
H
PO
OH
O
PO
OHO
P
O
OH
OH
OH
OH
H
OH
H
O
N
N
N
N
NH2
H
PO
OH
O
PO
OHOH + H3PO4
H 2 O , e n z ym e
+ energy
Adenosinetriphosphoric acid (ATP) - a universal carrier of energy for all forms of life on the Earth
Nucleic acids are esters, formed from nucleotides
Examples of dinucleotides:
OH
H
HH
O
H
NH
N
O
O
H3CPO
OH
OH
OH
H
H
OH
H
O
H
NH
N
O
O
H3CPO
O
OH
OH
OH
H
OH
H
O
N
N
N
N
NH2
H
PO
OH
OH
OH
H
O
H
O
N
N
N
N
NH2
H
PO
OH
OH
DNA is a polynucleotide, formed from deoxyribophosphates of adenine, thymine, cytosine and guanine
RNA is a polynucleotide, formed from ribophosphates of adenine, uracil, cytosine and guanine
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
Individual polynucleotide chainsinteract due to the H-bondingbetween complimentary bases,forming double strained DNAand RNA.
A sequence of three nucleotidesencodes incorporation of a specificaminoacid to a protein.
The double strain DNA, discoveredby Watson, Wilkins and Crick(1962 Nobel Prize), is the most common, but not the only formof DNA in living organisms.
Outline
1. Classification of carbohydrates2. Stereochemistry of open monosaccharides3. Cyclic forms of monosaccharides4. Base-catalyzed isomerisation of monosaccharides 5. Glycosides6. Reactions of monosaccharides7. Synthesis of monosaccharides8. Disaccharides and polysaccharides9. Pyrimidine and purine bases10. Nucleosides and nucleotides11. Structures of DNA and RNA12. Fluorescent detection of nucleic acids
Fluorescent detection of nucleic acids is base on their ability to interact withcertain dyes and restrict internal rotation of chromophoric fragments around conjugated bonds. It may reduce rotational dissipation of the light energy andinitiate fluorescence.
Example of a DNA-sensitive dye:
S
N+
CH3 N
COOH
CH3
H3C
S
N
CH3 N+
COOH
CH3
H3C
I-
I-