in medical, food, cosmetics, and agricultural sectors are produced by a range of microorganisms, e.g. bacteria, fungi, and algae. A wide range of microbial compounds with antioxidant, antiaging, and skin lightening effects have been identified. Microbial bioprocesses have been developed for production of organic acids, which are building blocks of many valuable products such as degradable polymers, polyesters, and bioplastics. Microbes have been demonstrated to be cell factories for production of bioactive compounds and recombinant proteins of biomedical relevance. Many microbial molecules of antimicrobial, antiviral, anti‐inflammatory, immunomodulatory, anticancerous, etc., properties have been reported. A diverse types of functional microbial molecules of ultra‐reduced calorie, prebiotic, and anti‐oxidative effects have been identified. Some phenolic compounds and mycosporine‐like amino acids of microbial origin have been reported to be sunscreen and antiaging effects. Several intriguing efforts have been made for developing bioprocesses for the economically viable production of polyhydroxyalkanoates and related copolymers, helpful in addressing the issues related with plastic uses.
This book represents a distinguished repository of knowledge around microbial bioprospecting. The book is useful to academicians and researchers in augmenting their understandings on the aspects mentioned above.
Acknowledgments
We are thankful to the Center of Innovative and Applied Bioprocessing and Panjab University, Chandigarh, for providing facility to complete this book. We are grateful to all the esteemed authors for their exceptional contributions and reviewers for their critical evaluation and suggestions for the quality improvement of the book.
We would like to thank Miss Rebecca Ralf (Commissioning Editor), Miss Kerry Powell (Managing Editor), and Nivetha Udayakumar (Content Refinement Specialist) from John Wiley & Sons, Ltd for their excellent management of this project and anonymous reviewers for their positive recommendations about the book.
We also appreciate the support of our friends and research students, whose discussion and comments were beneficial to shape this book. We thank our numerous colleagues for direct or indirect help in shaping this project.
SPS is grateful to his parents and family for consistent moral support. SPS acknowledges the support from CIAB and the Department of Biotechnology (DBT). SKU wishes to express gratitude to his parents, wife, and daughter for their endless support, patience, and inspiration.
We would like to warmly thank faculties and staffs of the department and university for providing a great working environment.
1 An Introduction to Microbial Biodiversity and Bioprospection
Tomoya Shintani1, Santosh Kumar Upadhyay2, and Sudhir P. Singh3
1 Department of Nutritional Representative – Supplement Adviser, The Japanese Clinical Nutrition Association, Tokyo, Japan
2 Department of Botany, Panjab University, Chandigarh, India
3 Center of Innovative and Applied Bioprocessing (DBT-CIAB), Mohali, Punjab, India
1.1 Introduction
1.1.1 Microorganisms
The term “microorganisms” refer to organisms that are so minute that the human eye cannot discern their structure. Almost all the unicellular organisms are included in the category of microorganisms. However, many multicellular organisms are microscopic. The microbes may also exist as cell clusters. Microbes are not limited to only eubacteria and archaea but also includes members from fungi, protozoa, algae, and viruses. Ribosomal RNA is considered a crucial molecule to draw an authentic classification of the life forms. On the basis of comparative rRNA sequence analysis, a basal universal phylogenetic tree had been inferred by Carl Woese [1], representing the overview of organismal history. This phylogenetic tree hypothesized the common origin of all forms of life, emphasizing the importance of microorganisms in the biological diversity at the Earth.
The global compilation of microbiological data has estimated the existence of about 1 trillion microbial species at the Earth [2]. The Earth Microbiome Project had been established in the year 2020, with the main objective to document the uncultured microbial diversity and the functional potential thereof [3]. In the project, sampling of the Earth's microbial communities is being done on an unprecedented scale. Recently, a total of 27 751 samples had been collected from 43 countries to characterize the microbial communities of diverse physicochemical properties and exposed to a wide range of biotic and abiotic factors [4].
1.1.2 Bioprospecting
Bioprospecting is the excavation of useful genetic or biochemical materials from natural resources [5]. The word “bio‐” refers to “organism” and “prospecting” refers to the search for precious material. Bioprospecting of the microbial population, residing in diverse ecological niches, is gaining more and more attention with the increasing demand for bioactive molecules and nutraceuticals of pharmaceutical, food, and agro‐industrial significance. Microorganisms exist in every corner of this planet, and many of them may not be cultivated. Bioprospecting of biologicals, including microbes, requires interdisciplinary knowledge to exploit the natural resource for societal benefits in a sustainable manner.
A major proportion of Earth contains extreme environmental, where most of the life forms cannot survive. However, extremophiles, which evolve a natural mechanism to thrive the harsh condition, are considered a rich biological resource for extremophiles [6]. The bioactive compounds and the extremozymes have great industrial importance [7]. There is an enormous genetic pool of microbes co‐evolved with the higher organisms, including plants and animals. They have manifold promising biomolecules of industrial importance [5]. There are boundless opportunities to explore the treasure box to meet the growing demand for novel bioactive molecules, e.g., food ingredients, agrochemicals, functional biomolecules, antibiotics, enzymes, and so on. Omics is a compelling approach for the exploration of various niches of diverse environmental conditions and the discovery of unusual novel enzymes and other metabolites of human use [8].
1.1.3 Bioprospection of Microorganisms
The microbial resources have potential in the generation of a wide range of high‐value compounds. This section has explained a few specific examples, the detail of which can be found in the subsequent chapters.
Biosurfactants are used in many fields, such as water treatment, food processing, health, disinfectants, cosmetics, and medicines [9]. Most biosurfactants are produced employing different strains of bacteria, yeast, and molds [10]. The uses of biosurfactants of microbial origin have been demonstrated in various purposes, for example in food processing, water treatment, cosmetics and pharmaceuticals, and bioremediation.
Microbial gum is a polysaccharide molecule mostly produced by bacteria and fungi [11]. These molecules protect the microbes from harsh environmental conditions [12]. These compounds are of widespread use in foods, pharmaceuticals, and cosmetics. The microbial gums are of prebiotic nature. Its uses have also been demonstrated in wound healing and carrier for drug delivery [13]. The demand for microbial gums is steadily increasing in various industries.
The practicality and potential of microbes in cosmetics have been well established. The use of antiaging products is in the spotlight. A variety of cosmetic compounds are produced from cultured microorganisms such as bacteria, yeasts, fungi, and algae [14].
