Microbes in Industrial Products Questions in English

(B) Retting is a process that uses the action of microorganisms and moisture on plants to dissolve or rot away much of the cellular tissues and pectin surrounding the bast-fiber bundles.
Specifically,species of $Clostridium$ (such as $Clostridium$ $butyricum$) are commonly used in the retting of fibers like jute and flax.
These bacteria produce enzymes that break down the pectic substances that bind the fibers together,thereby isolating the fibers from the plant stem.

(B) The process of curing tea and tobacco leaves involves the use of specific strains of bacteria.
This microbial activity helps in removing bitterness and developing the characteristic aroma and flavour of the leaves.

(D) The conversion of a sugary solution into vinegar (acetic acid) is carried out by the bacterium $Mycoderma$ $aceti$ (also known as $Acetobacter$ $aceti$).
This process involves the aerobic oxidation of ethanol,which is produced from the fermentation of sugar,into acetic acid.

(B) $Bacillus$ $megatherium$ is a bacterium known for its ability to synthesize vitamin $B_{12}$. In industrial microbiology,it is utilized in food processing and the production of various biochemicals,including vitamins and enzymes.

(B) Selman Waksman was awarded the Nobel Prize in Physiology or Medicine in $1952$ for his discovery of Streptomycin.
Streptomycin was the first antibiotic effective against tuberculosis.
It is produced by the actinobacterium $Streptomyces$ $griseus$.

(B) Wine turns sour due to the action of aerobic bacteria,specifically $Acetobacter$ $aceti$.
These bacteria oxidize the ethanol present in the wine into acetic acid in the presence of oxygen.
This process is known as acetification,which gives the wine a sour taste and converts it into vinegar.

(B) The bitterness of tea leaves is primarily due to the presence of certain compounds like tannins and caffeine. Certain bacteria,specifically $Bacillus$ species,are employed in the fermentation or processing of tea leaves to reduce this bitterness and enhance the flavor profile. Among the options provided,$Bacillus$ $megatherium$ is known for its role in the processing of tea leaves to remove bitterness.

(B) The process of retting involves the separation of fibres from the plant stem by the action of microorganisms.
In this process,bacteria decompose the pectin present in the plant tissues to liberate the fibres.
This process is primarily carried out by $Clostridium$ $butyricum$,which is a type of butyric acid bacterium.

(B) $Leuconostoc$ $mesenteroides$ is a bacterium that produces the enzyme dextransucrase. This enzyme catalyzes the conversion of sucrose into dextran,which is a complex branched glucan (polysaccharide). This process is commonly observed in the sugar industry where it can cause slime formation.

(A) The first antibiotic, Penicillin, was discovered by the British bacteriologist Alexander Fleming in $1928$. It was isolated from the fungus $Penicillium \, notatum$.

(B) $Penicillium roqueforti$ and $P. camemberti$ are specific species of fungi belonging to the genus $Penicillium$.
These fungi are widely used in the food industry, specifically in the process of cheese ripening.
$Penicillium roqueforti$ is used to produce blue-veined cheeses like Roquefort, while $P. camemberti$ is essential for the production of soft-ripened cheeses like Camembert and Brie.
They contribute significantly to the unique texture and flavour profile of these cheeses.

(A) $Aspergillus niger$ is a fungus that is commercially exploited for the industrial production of citric acid and oxalic acid from molasses.

(B) Chloromycetin, also known as chloramphenicol, is a broad-spectrum antibiotic.
It is primarily produced by the bacterium $Streptomyces \, venezuelae$.
Therefore, the correct option is $B$.

(D) . The yeast cells produce an enzyme complex known as $Zymase$. This complex is responsible for the process of fermentation,where it converts simple sugars like glucose and fructose into ethanol and carbon dioxide.

(D) The correct answer is $D$. Yeast,specifically $Saccharomyces$ $cerevisiae$ (Brewer's yeast),is widely used in the fermentation industry.
During the process of alcoholic fermentation,yeast utilizes the enzyme complex $Zymase$ to convert glucose into ethyl alcohol and carbon dioxide.
The chemical reaction is as follows:
$C_6H_{12}O_6 \xrightarrow{Zymase} 2C_2H_5OH + 2CO_2$
In this reaction,$C_6H_{12}O_6$ is glucose,and $C_2H_5OH$ is ethyl alcohol.

(D) Yeast, specifically $Saccharomyces$ $\text{cerevisiae}$, is economically significant due to its role in fermentation.
In the baking industry, yeast is used to produce $CO_2$ through fermentation, which helps the dough rise.
In the wine and brewing industry, yeast converts sugars into ethanol and $CO_2$, which is essential for the production of alcoholic beverages.

(C) The correct answer is $C$.
Campestrin is an antibiotic substance that can be isolated from certain yeast species,specifically $Candida$ species.
Ephedrin is an alkaloid,Saccharin is an artificial sweetener,and Polymixin is an antibiotic derived from the bacterium $Bacillus$ $polymyxa$.

(C) $Saccharomyces$ $\text{cerevisiae}$, commonly known as brewer's yeast, is used for the fermentation of sugars into alcohol.
During this process, the yeast breaks down sugars in the absence of oxygen to produce ethanol and carbon dioxide.

(D) Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes.
In the process of alcoholic fermentation, yeast cells secrete the enzyme complex known as $Zymase$.
$Zymase$ catalyzes the conversion of glucose $(C_6H_{12}O_6)$ into ethanol $(C_2H_5OH)$ and carbon dioxide $(CO_2)$.
The chemical reaction is: $C_6H_{12}O_6 \xrightarrow{Zymase} 2C_2H_5OH + 2CO_2$.

(C) The enzyme $Zymase$ is responsible for the fermentation process.
It converts glucose $(C_6H_{12}O_6)$ into ethyl alcohol $(C_2H_5OH)$ and carbon dioxide $(CO_2)$.
The reaction is as follows:
$C_6H_{12}O_6 \xrightarrow{Zymase} 2C_2H_5OH + 2CO_2$
Therefore,the correct option is $C$.

(A) The chemical equation for alcoholic fermentation is: $C_6H_{12}O_6 \rightarrow 2C_2H_5OH + 2CO_2$.
According to the stoichiometry of the reaction, $1$ mole of glucose produces $2$ moles of ethanol $(C_2H_5OH)$ and $2$ moles of carbon dioxide $(CO_2)$.
The molar mass of ethanol is approximately $46 \, g/mol$, and the molar mass of $CO_2$ is approximately $44 \, g/mol$.
Since the molar masses are very similar, in terms of mass, the production of ethanol and $CO_2$ occurs in a nearly $1:1$ ratio during fermentation.
Therefore, if $0.3$ tonne of alcohol is produced, approximately $0.3$ tonne of $CO_2$ is released into the atmosphere.

(C) $Micrococcus \text{ } ureae$ is a bacterium that produces the enzyme urease.
This enzyme catalyzes the hydrolysis of urea into ammonia and carbon dioxide.
The ammonia then reacts with water to form ammonium carbonate.
Therefore, the overall process involves the conversion of urea into ammonium carbonate.

(A) In $1929$,Alexander Fleming,while working on $Staphylococcus$ bacteria,observed that a mold called $Penicillium$ $notatum$ was growing in one of his unwashed culture plates around which the bacteria could not grow. He discovered that this mold produced a chemical that inhibited the growth of the bacteria. He named this chemical $Penicillin$ after the mold $Penicillium$ $notatum$.

(A) Rishikesh is home to the $IDPL$ ($Indian$ $Drugs$ $and$ $Pharmaceuticals$ $Limited$),which is a major public sector undertaking in India. It is primarily known for the large-scale manufacturing of various essential drugs,including antibiotics,vitamins,and other pharmaceutical products.

(B) $Cyclosporin$ is used as an immunosuppressant. This drug is derived from a fungus and inhibits the activity of helper $T$-cells,thus helping to prevent the rejection of organ transplants.

(D) Beer is an alcoholic beverage produced by the fermentation of starch-based materials.
$Hordeum vulgare$ (barley) is the most common grain used for brewing beer.
However,other cereals like rice and maize are also used as adjuncts or primary sources of starch in various brewing processes globally.
Therefore,all the mentioned options can be used for the fermentation process to produce beer.

(C) Wine is an alcoholic beverage produced through the process of fermentation.
In this process, the yeast $Saccharomyces \, cerevisiae$, commonly known as Brewer's yeast, is used to ferment the sugars present in grape juice.
During fermentation, the yeast converts glucose into ethanol $(C_2H_5OH)$ and carbon dioxide $(CO_2)$ under anaerobic conditions.

(D) Lactic acid is produced through the microbial fermentation of lactose (milk sugar).
Various microorganisms are involved in this process.
$Lactobacillus$ $bulgaricus$ and $Streptococcus$ $lactis$ are well-known bacteria used in the dairy industry for lactic acid production.
Additionally,certain fungi such as $Rhizopus$ $oryzae$ are also capable of producing lactic acid through fermentation.
Therefore,all the listed organisms are involved in the production of lactic acid.

(B) Vinegar is produced through a two-step fermentation process.
First,yeast converts sugars into ethanol (alcohol).
Second,the bacterium $Acetobacter$ $aceti$ oxidizes the ethanol into acetic acid,which is the main component of vinegar.

(C) The first antibiotic to be discovered and isolated was Penicillin.
It was discovered by Alexander Fleming from the fungus $Penicillium$ $notatum$.
It is often referred to as a 'wonder drug' due to its significant role in treating bacterial infections.

(A) Yeast $(Saccharomyces \text{ } cerevisiae)$ is used in the industrial production of ethanol $(C_2H_5OH)$.
When yeast is added to a sugar solution, it performs fermentation, which converts sugars into alcohol and carbon dioxide $(CO_2)$.

(C) The correct answer is $C$.
$Aspergillus$ $niger$ is a fungus that is widely used in the industrial production of organic acids.
Specifically,it is employed for the fermentation of sugar syrups to produce citric acid.
Additionally,many species of $Aspergillus$ are involved in the oxidation of glucose,which leads to the production of gluconic acid.

(A) Ascorbic acid (Vitamin $C$) is produced through a complex modification of glucose using various species of the genus $Acetobacter$. Specifically,$Acetobacter$ species are employed in the industrial fermentation process to convert glucose into sorbitol and subsequently into ascorbic acid.

(B) Streptomycin is an antibiotic produced by the bacterium $Streptomyces$ $griseus$.
It functions by inhibiting bacterial protein synthesis through its interaction with the $30S$ subunit of the ribosome.

(C) Terramycin, also known as oxytetracycline, is a broad-spectrum antibiotic.
It is produced by the soil bacterium $Streptomyces$ $rimosus$.
$Streptomyces$ $venezuelae$ produces chloramphenicol, $Streptomyces$ $aureofaciens$ produces chlortetracycline, and $Streptomyces$ $griseus$ produces streptomycin.

(D) $A. Fleming$ $(1929)$ discovered the antibiotic penicillin while working on $Staphylococcus$ bacteria. He observed that the mold $Penicillium$ $notatum$ inhibited the growth of these bacteria,marking the discovery of the first antibiotic.

(C) Germinating barley seeds,known as malt,are a primary ingredient in the production of beer.
During the malting process,barley seeds are allowed to germinate,which activates enzymes like amylase that convert starch into fermentable sugars.
These sugars are then fermented by yeast to produce alcohol and carbon dioxide,resulting in beer,which typically has an alcohol content of $4-8\%$.

(C) The correct answer is $C$. The ability of fungi, specifically $Rhizopus$ $stolonifer$, to perform microbial hydroxylation of steroids was demonstrated by Murray and Peterson in $1950$. This discovery was a landmark in the industrial production of steroid hormones.

(B) Rennet is a complex of enzymes produced in the stomachs of ruminant mammals. It contains the enzyme chymosin,which is used in the process of cheese making to coagulate milk proteins (casein),leading to the formation of curd.

(B) The correct answer is $B$.
Lactic acid is the first organic acid produced by fermentation.
It is obtained through the metabolic activity of various bacteria such as $Streptococcus$ $lactis$,$Lactobacillus$ $delbrueckii$,and the fungus $Rhizopus$.

(D) It has been demonstrated that $Propionibacterium$ species have the highest potential to accumulate vitamin $B_{12}$ intracellularly.
$Propionibacterium$ $shermanii$ and $Propionibacterium$ $freudenreichii$ are the most widely used species for this purpose.
$Propionibacteria$ produce vitamin $B_{12}$ intracellularly and excrete mainly propionic acid and acetic acid extracellularly.
All $Propionibacterium$ strains employed for vitamin $B_{12}$ production are microaerophilic and produce high yields of vitamin $B_{12}$ only under very low oxygen concentrations.

(C) Yeast cells,specifically $Saccharomyces \ cerevisiae$ (brewer's yeast),perform a metabolic process known as fermentation.
In this anaerobic process,yeast converts sugars into ethanol and carbon dioxide.
This process is widely used in the production of bread,beer,wine,and other alcoholic beverages.
Therefore,the correct option is $C$.

(B) Sir Alexander Fleming discovered the first antibiotic, penicillin, in $1928$.
He extracted it from the blue-green mold known as $Penicillium$ $notatum$ while working with staphylococci bacteria on agar-agar medium.

(C) Antibiotics are chemical substances produced by some microbes and can kill or retard the growth of other disease-causing microbes.
$A$. Griseofulvin is an antifungal antibiotic.
$B$. Cephalosporin is a well-known group of antibiotics.
$C$. Citric acid is an organic acid produced by the fungus $Aspergillus$ $niger$,not an antibiotic.
$D$. Streptomycin is an antibiotic produced by $Streptomyces$ $griseus$.
Therefore,Citric acid is not an antibiotic.

(D) Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes.
In the case of sugar conversion to alcohol,the enzyme $Zymase$ acts as a biocatalyst.
$Zymase$ is a complex of enzymes produced by yeast $(Saccharomyces \ cerevisiae)$ that catalyzes the fermentation of sugar into ethanol and carbon dioxide.
Therefore,the direct chemical action is performed by the enzyme $Zymase$.

(D) The brewing industry produces various types of alcoholic beverages depending on the fermenting agent and the raw material used.
$Saccharomyces$ $cerevisiae$,commonly known as brewer's yeast,is the primary organism used for alcohol fermentation.
Other species like $S. sake$,$S. ellipsoidens$ (wine yeast),and $S. pireformis$ (ginger yeast) are also used in specific fermentation processes.

(A) Citric acid is commercially produced by the aerobic fermentation of sucrose present in beet molasses using the fungus $Aspergillus$ $niger$.
$Aspergillus$ $niger$ is a filamentous fungus widely used in the biotechnology industry for the production of organic acids.

(B) Antibiotics are chemical substances,which are produced by some microbes and can kill or retard the growth of other (disease-causing) microbes.
$Penicillium$ $notatum$ is a well-known fungus used for the production of the first antibiotic,penicillin.
While $Mucor$ and $Agaricus$ are fungi,they are not primarily known for the commercial production of antibiotics in the same context as $Penicillium$.
Therefore,the most accurate answer among the given options is $Penicillium$.

(C) Rennin,also known as chymosin,is a proteolytic enzyme.
It is extracted from the fourth stomach of young ruminants (like calves).
In the cheese industry,it is used to coagulate milk proteins (casein) to form curd,which is the essential first step in cheese production.