biochemistry lab experiments pdf

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• Dr. Elizabeth Vogel Taylor

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• Biochemistry

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Biochemistry laboratory.

Complete student manual ( PDF )

Supplemental TA instructions ( PDF )

Table of contents ( PDF )

Appendix A-D and references ( PDF )

Equipment and supplies list ( PDF )

The table below contains links to the instructions for each lab session, as well as links to photographs of the labs.

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Basic Techniques in Biochemistry, Microbiology and Molecular Biology

Principles and Techniques

• © 2020
• Aakanchha Jain 0 ,
• Richa Jain 1 ,
• Sourabh Jain 2

Bhagyoday Tirth Pharmacy College, Sagar, India

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Centre for Scientific Research and Development, People’s University, Bhopal, India

Sagar institute of pharmaceutical sciences, sagar, india.

• Describes experimental protocols in a simplified manner
• Covers all relevant practical details for a given experiment
• Introduces various tools used in molecular biology

Part of the book series: Springer Protocols Handbooks (SPH)

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Table of contents (62 protocols)

Front matter, instruments, bod (biochemical oxygen demand or biological oxygen demand) incubator.

• Aakanchha Jain, Richa Jain, Sourabh Jain

Laminar Air Flow/Biosafety Cabinets

Aseptic hood, hot air oven, deep freezer (−20 °c) (low-temperature cabinet), refrigerator, compound microscope, digital colony counter, digital turbidity meter, digital nephelometer, digital photocolorimeter, digital uv/visible spectrophotometer, polymerase chain reaction, elisa reader, molecular biology, enzyme assay: qualitative and quantitative.

• Microorganisms
• Extremophiles
• Oxidative fermentation
• Thermophiles
• Psychrophiles

About this book

This book presents key methodologies, tools and databases for biochemistry, microbiology and molecular biology in simple and straightforward language. Covering all aspects related to experimental principles and procedures, the protocols included here are brief and clearly defined, and include essential precautions to be taken while conducting experiments. The book is divided into two major sections: one on constructing, working with, and standard operating procedures for laboratory instruments; and one on practical procedures used in molecular biology, microbiology and biochemical analysis experiments, which are described in full.

Authors and Affiliations

Aakanchha Jain

Sourabh Jain

About the authors

Bibliographic information.

Book Title : Basic Techniques in Biochemistry, Microbiology and Molecular Biology

Book Subtitle : Principles and Techniques

Authors : Aakanchha Jain, Richa Jain, Sourabh Jain

Series Title : Springer Protocols Handbooks

DOI : https://doi.org/10.1007/978-1-4939-9861-6

Publisher : Humana New York, NY

eBook Packages : Springer Protocols

Copyright Information : Springer Science+Business Media, LLC, part of Springer Nature 2020

Hardcover ISBN : 978-1-4939-9860-9 Published: 28 February 2020

Softcover ISBN : 978-1-4939-9863-0 Published: 04 August 2021

eBook ISBN : 978-1-4939-9861-6 Published: 27 February 2020

Series ISSN : 1949-2448

Series E-ISSN : 1949-2456

Edition Number : 1

Number of Pages : XIV, 282

Number of Illustrations : 11 b/w illustrations, 39 illustrations in colour

Topics : Biomedical Engineering/Biotechnology , Biological Techniques , Pharmaceutical Sciences/Technology

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Biochemistry in the Lab

DOI link for Biochemistry in the Lab

Get Citation

Most lab manuals assume a high level of knowledge among biochemistry students, as well as a large amount of experience combining knowledge from separate scientific disciplines. Biochemistry in the Lab: A Manual for Undergraduates expects little more than basic chemistry. It explains procedures clearly, as well as giving a clear explanation of the theoretical reason for those steps.

Key Features:

• Presents a comprehensive approach to modern biochemistry laboratory teaching, together with a complete experimental experience
• Includes chemical biology as its foundation, teaching readers experimental methods specific to the field
• Provides instructor experiments that are easy to prepare and execute, at comparatively low cost
• Supersedes existing, older texts with information that is adjusted to modern experimental biochemistry
• Is written by an expert in the field

This textbook presents a foundational approach to modern biochemistry laboratory teaching together with a complete experimental experience, from protein purification and characterization to advanced analytical techniques. It has modules to help instructors present the techniques used in a time critical manner, as well as several modules to study protein chemistry, including gel techniques, enzymology, crystal growth, unfolding studies, and fluorescence. It proceeds from the simplest and most important techniques to the most difficult and specialized ones. It offers instructors experiments that are easy to prepare and execute, at comparatively low cost.

TABLE OF CONTENTS

Chapter 1 | 7  pages, chapter 2 | 12  pages, chapter 3 | 9  pages, protein concentration, chapter 4 | 5  pages, chapter 5 | 8  pages, salting out proteins and other biomolecules, chapter 6 | 7  pages, a discussion of isoelectric point and effective charge, chapter 7 | 15  pages, column chromatography, chapter 8 | 11  pages, michaelis–menten kinetics, chapter 9 | 7  pages, protein purification, chapter 10 | 11  pages, polyacrylamide gels, chapter 11 | 14  pages, in silico biochemistry the evolution of globins, chapter 12 | 10  pages, growing crystals of hemoglobin, chapter 13 | 10  pages, enzyme inhibition, chapter 14 | 7  pages, multisubstrate kinetics, chapter 15 | 14  pages, fluorescence and denaturation, chapter 16 | 10  pages, fluorescence studies of ligand binding, chapter 17 | 10  pages, dna restriction digests, chapter 18 | 6  pages, western blotting.

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7 Biochemistry Lab Experiments that are Easier to Teach with Labster

You want the best biochemistry labs for your students. Maybe lesson planning is taking up too much time, you’re recycling the same labs over and over, or you’re a new teacher. Whatever the case, we’ve gathered 7 biochemistry lab experiments that you can teach your students. We’ve also matched accompanying virtual labs that can help teach some of the experiments.

• DNA/RNA Sequencing
• Gel Electrophoresis
• Antibodies & Antigens
• Blotting Methods
• Polymerase Chain Reaction (PCR)

ELISA stands for enzyme-linked immunosorbent assay. basic assay technique. Trying to capture a specific protein amongst thousands of types of proteins is like looking for a needle in a haystack, but it’s easier with this basic assay technique. Instructors can provide ELISA kits if budgets allow.

There are incubation times necessary with this method, so the collapsed time aspect of using a virtual lab is useful! Labster has an ELISA Virtual Lab where students can help a doctor quantify Factor IX protein, which is used for hemophilia drugs.

Figure alt text: Sealing an ELISA plate using a microplate seal in a virtual lab.

2.) DNA/RNA Sequencing

With the right equipment, DNA & RNA sequencing can be straightforward and easy. Fast and affordable sequencing matters, as it opens up a whole new world for biology/biochemistry research. There are a variety of ways to do sequencing, but they can be expensive - especially for a lab class. 

Labster has a few sequencing labs, one being RNA Extraction: Sample and purify mRNA from pigs where students can learn how to extract RNA from pig fat tissue samples and how to purify messenger RNA using magnetic beads.

3.) Nutrition

There’s a great deal of biochemistry research done in the field of nutrition such as understanding how food relates to cancer and how food can promote health. A CUNY lab exercise guide outlines some different hands-on labs instructors can do such as “The Microbiology of Milk and Food.”

Some concepts can be difficult to get across to students in a regular lab or through lecturing. That’s where our 3D animations and interactivity are most impactful. Labster has a Carbohydrates virtual lab where students can visualize and explore how carbohydrates are broken down by the digestive system and taken up into the bloodstream.

Figure alt text: Reviewing various carbohydrates in a virtual lab.

4.) Gel Electrophoresis

This technique is used to separate components of a mixture, often DNA, RNA, or proteins. Kits are available to do this experiment in the classroom if the budget allows for it. Virtual lab simulations are a cost-effective alternative Not only are they helpful for learning the technique itself, but also to visualize the components. 

In Labster’s Gel Electrophoresis virtual lab , students will solve a crime by using DNA fingerprinting to identify a thief. Students will use nucleic acid gel electrophoresis to separate and visualize DNA molecules and watch an animation to understand what happens inside the gel tank.

 5.) Antibodies & Antigens

Antibodies and Antigens can be difficult to teach but Labster has a free 3D animation video on “Antigen-Antibody Binding - Why are some blood types incompatible?” Utilizing videos, interactive simulations, lectures, and images help to differentiate teaching approaches and support students in learning these concepts. 

In Labster’s Antibodies virtual lab , learn about the concepts of antibodies and antigens, as well as the ABO and Rhesus blood grouping systems and their importance in blood transfusions. Then, they will help a young couple determine the potential risk for Rhesus disease in their unborn child.

Figure alt text: Tight antibody-antigen complex.

6.) Blotting Methods

Students need to use blotting methods to identify DNA, RNA, and other proteins. There are a variety of blots: Northern, Southern, Eastern, and Western (1). This technique can be done in the lab - but it is notoriously difficult at first. Practicing in a virtual lab helps students grasp the methods and understand how to analyze their results.

In our Western Blot virtual lab , students perform a western blot experiment to ultimately provide data and knowledge to identify a promising treatment for breast cancer.

7.) Polymerase Chain Reaction

Polymerase Chain Reaction (PCR) is used to amplify or make multiple copies of DNA (1). It can be expensive to run these labs as PCR labs are expensive and time-consuming. This is where virtual labs can help!

In the Polymerase Chain Reaction (PCR) simulation , students will be thrown right into a crime scene where a murder has taken place. After investigating the crime scene, their first task is to collect blood samples in the hope that the murderer has left traces of their DNA. A 3D animation will show the PCR experiment at the molecular level, illustrating the structure of DNA and its replication.

If you’re interested in teaching PCR in an approachable way, check out our PCR blog post . 

Questions for consideration?

• How could you incorporate these virtual labs into your teaching plans?
• Are these labs better as self-paced homework assignments or small-group collaboration in class?

(1) Shaw, Vikram. (n.d.), Biochemistry Lab Techniques for the MCAT: Everything You Need to Know. Shemassian Academic Consulting. Retrieved from: https://www.shemmassianconsulting.com/blog/biochemistry-techniques-mcat#part-7-centrifugation-and-chromatography

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Biochemistry laboratory : modern theory and techniques

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Laboratory Experiments

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Experiment_728_Qualitative Testing of Carbohydrates 1_1

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Experiment 728:  Qualitative Analysis of Carbohydrates  

Section 1:  Purpose and Summary:    

Develop an understanding of what carbohydrates are. 

Identify different types of carbohydrates. 

Observe how different carbohydrates react in different chemical tests. 

What are carbohydrates?  

Carbohydrates are a class of natural compounds that contain either an aldehyde or a ketone group and many hydroxyl groups – they are often called polyhydroxy aldehydes or ketones. A  monosaccharide  consists of a single carbohydrate molecule, containing between 3 and 7 carbons. Glucose and fructose are examples of monosaccharides. A  disaccharide  consists of two monosaccharides that are linked together.  Sucrose and lactose are disaccharides. A  polysaccharide  consists of many monosaccharides linked together. Starch, pectin, glycogen, and cellulose are examples of polysaccharides. 

Carbohydrates are used for energy. The carbohydrates that we eat are broken down in our bodies and eventually form water and carbon dioxide. The energy obtained in this process is used for other reactions that must occur in the body. Excess carbohydrates that we eat can be stored in the liver as glycogen or can be converted to fats. Plants create carbohydrates in the process of photosynthesis, where energy from the sun is used to build carbohydrates from water and carbon dioxide. 

Monosaccharide structures can be written as Fischer projections (they are named after Emil Fisher who first used them in 1891). In a Fischer projection, the structure is drawn vertically with the carbonyl carbon at the top. It is understood that for each chiral carbon in the molecule, the horizontal bonds point out of the page (toward you) and the vertical bonds point into the page (away from you). Fischer projections are used to indicate the stereochemistry of each chiral carbon in the molecule and to compare monosaccharide structures easily. For example, there are many compounds with the same connections of atoms but different stereochemistry, and they all have different names! The Fischer projections for glucose and galactose are shown below.   Note that the only difference between these sugars is the stereochemistry around carbon 4, yet they have different names. 

In solution, most monosaccharides exist in a cyclic form – the aldehyde or ketone group reacts with one of the –OH groups on the other end of the same molecule to form a cyclic hemiacetal. Shown here are the cyclic structures for D-glucose. Notice that there are two possibilities: α-D-glucose and β-D-glucose. These are called the different anomers of glucose. In solution, there is an equilibrium between the cyclic form and the open chain or free aldehyde form. The rings are constantly opening up and closing again. In this way, the alpha and beta forms can be interconverted.  

Chemical Tests for Carbohydrates  

A  reducing sugar  is one that can be oxidized. In order to be a reducing sugar, the molecule must contain a free anomeric carbon, since it is the open-chain form of the aldehyde that is able to react (and be oxidized).  One test for reducing sugars involves  Fehling’s reagent , which contains Cu 2 +  ions in an aqueous basic solution. If a reducing agent is present, the Cu 2 +  is reduced to Cu +  and forms a red precipitate of Cu 2 O.  Therefore, if Fehling’s solution is added to a solution containing a reducing sugar, a red precipitate will form. Sometimes the reaction mixture must be heated in order for the precipitate to form. The color of the precipitate can vary from red to orange to green (the green color is actually a mixture of an orange and a blue precipitate). 

Barfoed’s test  is similar to Fehling’s test, except that in Barfoed’s test, different types of sugars react at different rates. Barfoed’s reagent is much milder than Fehling’s reagent. Reducing monosaccharides react quickly with Barfoed’s reagent, but reducing disaccharides react very slowly or not at all. Therefore, it is possible to distinguish between a reducing monosaccharide and a reducing disaccharide using Barfoed’s reagent. A positive test is a dark red precipitate and is evidence of a reducing monosaccharide. 

In  Seliwanoff’s test , a dehydration reaction is involved. Seliwanoff’s reagent contains a non-oxidizing acid (HCl) and resorcinol. When a ketose (sugars with a ketone group) is reacted with this reagent, it becomes dehydrated and a cherry-red complex forms (not a precipitate). Aldoses (sugars with an aldehyde group) also react with this reagent, but much more slowly than ketoses. When Seliwanoff’s reagent is reacted with a disaccharide or a polysaccharide, the acid in the solution will first hydrolyze them into monosaccharides, and the resulting monosaccharides can then be dehydrated. Disaccharides and polysaccharides will therefore react slowly with Seliwanoff’s reagent. When you carry out this test, it is important to note the time required for a reaction to occur.   

Iodine  forms a blue, black, or gray complex with starch and is used as an experimental test for the presence of starch. The color of the complex formed depends on the structure of the polysaccharide and the strength and age of the iodine solution. Iodine does not form a complex with simpler carbohydrates (monosaccharides and disaccharides). Amylose (starch) is helically coiled in solution, and it is this helical structure that is necessary to form the blue complex with iodine. Monosaccharides and disaccharides are too small to be helically coiled. Amylopectin, cellulose, and glycogen 

form different colors with iodine – red, brown, or purple. 

Many carbohydrates can undergo  fermentation  in the presence of yeast. The carbohydrate is the food source for the yeast, and the products of the fermentation reaction are ethanol and carbon dioxide gas. 

C 6 H 12 O 6  →2 CH 3 CH 2 OH + 2 CO 2  (g) 

  Glucose         Ethanol 

Fermentation is used in the processes of making beer and wine, where the alcohol produced by the yeast is the desired product. Not all sugars, however, can be used by yeast as a food source. You will test which sugars ferment in the presence of yeast and which ones do not. The evidence of fermentation will be the evolution of carbon dioxide gas. In the test, a quantity of a solution (containing yeast and the sugar to be tested) will be trapped in an upside-down small test tube. After a few days, you will check to see if a gas bubble has formed in the test tube. If there is a gas bubble, it means fermentation did occur. 

Disaccharides and polysaccharides can be  hydrolyzed  in the presence of acid or specific enzymes. When a disaccharide is hydrolyzed, the products are the individual monosaccharides. When a polysaccharide is hydrolyzed, the products will depend on how long the mixture is allowed to react, the concentration of acid or enzyme, and other factors. Polysaccharides are very long and have many glycosidic bonds to hydrolyze. They cannot all be hydrolyzed at the same time, so the product is a mixture of dextrin, maltose, and glucose. If a polysaccharide sample is hydrolyzed completely (which means that it must react for a while), the product is glucose. In this experiment, you will hydrolyze a sample of sucrose and then test it for the presence of a reducing sugar. You will also hydrolyze a sample of starch and then test it for the presence of both a reducing sugar and starch. 

Section 2:  Safety Precautions and Waste Disposal  

Safety Precautions:  

Wear your safety goggles. 

Waste Disposal:  

At the end of the experiment, all wastes go into the inorganic waste container. 

Section 3: Procedure  

Post Lab Questions :  

1. According to the results of each part of the experiment, identify your unknown and explain your reasoning. 

2. Compare the results you obtained for the Fehling’s test of sucrose to the Fehling’s test of hydrolyzed sucrose. Explain your results. 

3. Compare the results you obtained for the Fehling’s test of starch to the Fehling’s test of hydrolyzed starch. Explain your results. 

4. Compare the results you obtained for the iodine test of starch to the iodine test of hydrolyzed starch. Explain your results. 

5. What is meant by the term “reducing sugar”? 

6. What is the purpose of testing water in the Seliwanoff’s test and the iodine test? 

7. Draw the ring structures for α-D-fructose and for β-D-fructose. 

8. An unknown carbohydrate gave a red precipitate when tested with Fehling’s reagent, turned red when reacted with Seliwanoff’s reagent, and quickly gave a red precipitate when reacted with Barfoed’s reagent. What conclusions can be made about this carbohydrate? 

9. What test could be used to differentiate between sucrose and lactose? Explain. 

10. What test could be used to differentiate between glucose and starch? Explain. 

11. What test could be used to differentiate between glucose and fructose? Explain. 

12. Why don’t all of the disaccharides undergo fermentation with yeast?