Products of Biochemical Engineering

How long ago?

• Sumerians and Babylonians were brewing before 6000 BC (evidence in pyramids)

• Egyptians “let my people go” were baking before 4000 BC

• Distilleries? 14th C.

Ancient biotechnologies

• vinegar for fries... acetic acid bacteria

• lactic acid to acidify milk... yogurt

• cheese to stabilize milk... bacteria and molds

Industrial age

• glycerol fermentation developed by german biochemist Carl Neuberg during WW1

• butanol/acetone fermentation developed by chemist Chaim Weizmann using Clostridium acetobutylicum

Antibiotics

• folk medicine: moldy cheese, meat, bread

• Tyndall, Pasteur, Roberts noted antagonistic effects of one organism on another... 1870’s

Alexander Fleming

• noted that Penicillium notatum contaminant killed culture of Staphylococcus aureus (1928)

• penicillin production reality in 1941

Penicillin

• prepared in highly dilute, impure and unstable solutions prior to WWII

• up to 1943, batch purification process that inactivated up to 65%

• Shell chemical engineers build pilot plant that processed 750 L broth/day with 85% recovery

more on penicillin

• 1943 – 4,100 patients/month• 1944 – 250,000 patients/month• MIT chemical engineers built

first production plant involving freeze drying technologies in 1942/43

Bugs on steroids?

• the superbug: td = 10 to 15 min

Classes of industrial microbes

• bacteria

• molds (fungi)

• yeast (fungi)

• actinomycetes

Prowhat?

• Procaryotes – nuclear region, single strand of ds-DNA– bacteria,

actinomycetes, blue-green algae

• Eucaryotes – nucleus, multiple chromosomes

Other industrial cultures

• tissue culture: mammalian, insect...

• plant tissue culture

Classes of products

• Microbial cells

• Large molecules (104 – 106 daltons)

• Primary metabolites (essential for growth)

• Secondary metabolites (who knows why?)

Microbial cells

• single cell protein• yeasts used in

brewing, baking

Microbial cells

• cells used in bioconversion, biotransformation reactions– ethanol --- acetic acid (Babylon, 5000

BC)– isopropanol --- acetone– sorbitol --- sorbose (manufacture of

vit.C)– steroid transformations– fumarate --- malate

Large molecules

• enzymes as catalysts– amylases in brewing,

baking, textiles– proteases in brewing,

meat tenderizing, detergents, leather (rennin)

Enzymes as catalysts

• ambient T and P (low energy)

• water solvent

• few side reactions (no by-products)

• highly specific for substrate

• high yields possible

• costly and can be unstable

• difficult to separate and reuse

High fructose corn syrup

corn starch (α1,4 glucose)

soluble dextrins(oligosaccharides)

glucose syrup

fructose syrup (50/50)

liquefaction (α-amylase)

saccharifaction (glucamylase)

isomerization (glucose isomerase)

Polysaccharides

• Xanthan from Xanthomonas campestris

• food additives as stabilizers, thickeners, emulsifiers

• drilling muds

Pullulan

• polysaccharide produced by Aureobasidium pullulans (fungus)

• edible and biodegradable films (low O2 permeability)

Primary metabolites

• amino acids: L-glutamic acid, L-lysine

• purine nucleotides: IMP (inosine 5’monophosphate)

• vitamins: riboflavin, B12

• organic acids: citric, gluconic, fumarate, malate

• solvents: ethanol, 2,3 butanediol

• plants in Ontario (4) and Quebec (1)

Secondary metabolites

• antibiotics: bacitracin, erythromycin

• toxins: mycotoxins• alkaloids• growth factors• pigments, flavours,

fragrances

Were you paying attention?

• Big Mac sauce: soybean oil, pickles, vinegar, water, sugar egg yolks, high fructose corn syrup, mustard, salt, xanthan, potassium sorbate, spice, soy, corn and wheat protein, EDTA

• water, glucose-fructose syrup, colour, phosphoric acid, natural flavours, caffeine

water, glucose-fructose,citric acid, tea, lemon flavour

chicken broth, egg noodles, waterchicken, salt, chicken fat, corn starchmonosodium glutamate, onion,yeast extract, spice, beta carotene, garlic

sorbitol, water, silica, glycerin,sodium alkyl sulfate,polyethylene glycol-6, flavour,xanthan, saccharin, triclosan,carbopol 956, titanium dioxide,sodium fluoride, tetrasodiumpyrophosphate