Definitions [5]
Define the following term
Zymology
Zymology is an applied science which deals with the biochemical process of fermentation and its practical uses.
Define the following term
Antibiotics
Antibiotics are chemical substances produced by microorganisms which can kill or retard the growth of other disease causing microbes even in low concentration. Antibiotic means “against life”.
Define the following terms
Superbug
"Superbug" is a term used to describe strains of bacteria that are resistant to the majority of antibiotics commonly used today.
Definition: Zymology
Zymology is the applied science that deals with the biochemical processes of fermentation and their practical uses.
Definition: Oenology
Oenology is the science and study of wine and winemaking.
Key Points
Key Points: Microbes in Household Products
| Product | Micro-organisms Used | Function |
|---|---|---|
| Curd | Lactobacillus (LAB) | Converts milk into curd, increases vitamin B₁₂ |
| Butter | Streptococcus cremoris, Leuconostoc dextranicum | Gives flavour and aroma |
| Yogurt | Lactobacillus bulgaricus, Streptococcus thermophilus | Ferments milk at 40°C |
| Cheese | Streptococcus lactis, Leuconostoc, fungi | Curdling and ripening of cheese |
| Swiss Cheese | Propionibacterium shermanii | Produces CO₂, forms holes |
| Roquefort Cheese | Penicillium roqueforti | Ripening and flavour |
| Camembert Cheese | Penicillium camemberti | Soft texture and taste |
Key Points: Microbes in Industries
- Microbes are cultured in large industrial fermenters to produce highly valuable secondary metabolites during their stationary growth phase.
- Specific strains of yeast are widely utilised in the commercial fermentation process to manufacture various alcoholic beverages from cereals and fruit juices.
- Industrial enzymes secreted by microbes serve practical daily purposes, such as clarifying bottled fruit juices and removing stubborn stains in laundry.
- Microorganisms are the primary source of life-saving medical treatments, producing essential antibiotics and critical bioactive molecules like immunosuppressants.
- Advanced biological techniques rely on microbes to commercially synthesise essential human proteins, dietary vitamins, and plant growth hormones.
Key Points: Microbes in Sewage Treatment
- Sewage = 99.5–99.9% water + 0.1–0.5% organic/inorganic matter + microbes (bacteria, viruses, fungi, algae, etc.)
- Preliminary Treatment - Bar screens remove large solids; Grit Chamber removes sand & stones.
- Primary Treatment - The sedimentation tank settles suspended solids and reduces coliform bacteria. Removes ~50–70% solids.
- Secondary Treatment - Aerobic bacteria decompose organic matter in aeration tanks, lowering BOD by 70–80%.
- Tertiary Treatment - Anaerobic bacteria digest sludge in sludge digesters; disinfection improves water quality.
- Chlorination kills any remaining pathogenic bacteria before water is released.
- Disposal - Treated water → natural water bodies; digested sludge → proper disposal/manure.
