eChapters

Introduction
In recent years, there has been a growing interest in alternative nutritious food sources (McClements, 2020) and such group of foods that has gained significant attention is millets. Millets are a diverse group of small-seeded grasses that have been cultivated and consumed for thousands of years. They are rich in essential nutrients such as proteins, fibers, vitamins, and minerals, making them an important addition to a balanced diet. Millets are not only rich in essential nutrients but also have several health benefits. They are known to have nutraceutical properties, low glycemic index, making them suitable for individuals with diabetes. Additionally, millets are a good source of antioxidants, which can help in reducing the risk of chronic diseases such as heart disease and cancer. The diverse range of millet varieties also provides flexibility in incorporating them into various dishes, making them suitable for different culinary preferences and dietary requirements. Therefore, the usage of millets can play a crucial role in promoting sustainable and healthy eating habits.
Malnutrition continues to be a pressing issue worldwide, particularly in developing countries (Ashok et al., 2020). The lack of access to nutritious food is one of the main causes of malnutrition, leading to various health problems such as obesity, diabetes, cardiovascular diseases, cancer, and celiac disease (Birania et al., 2020). To address this issue, millets have emerged as a promising solution. Despite being nutritionally superior to other cereals, millets have traditionally been limited to consumption by the poor and those with conventional dietary practices. However, there is a growing recognition of the potential of millets in combating malnutrition and improving public health. Millets, such as finger millet, pearl millet, and sorghum, are often referred to as “superfoods” due to their high nutritional content (Singh et al., 2020). These grains are rich in protein, carbohydrates, fats, vitamins, minerals, and dietary fiber, making them an ideal source of essential nutrients (Ashok et al., 2020). Additionally, millets are easily available and costeffective, making them a viable option for addressing malnutrition on a larger scale (Birania et al., 2020). Furthermore, millets are resilient crops that can withstand environmental changes and water shortages, making them an ideal choice for sustainable agriculture. In this chapter, we delve deeper into specific aspects of millet nutrition, examining their micronutrient profiles, health benefits, culinary versatility, and potential applications in combating malnutrition and promoting sustainable agriculture. By understanding the nutritional richness of millets, we can uncover innovative solutions for improving human health and fostering agricultural resilience.

Abstract

Amongst all types of major land-use change, extending irrigated agriculture using a surface-water source has the greatest influence on groundwater – both significantly increasing recharge and changing water quality as excess irrigation water infiltrates into shallow aquifers. Hence, in order to understand the impact of the landuse on the groundwater system the study has been aimed to understand the process by adopting geophysical, geochemical and microbial analysis of groundwater samples. The study has been conducted in Chidambaram taluk, with a total area of 92.51Sq.km. A total of 39 groundwater samples were collected for the analysis of major cation and anion along with the microbial analysis, like Total Coliform, Total Viable Counts, Fecal coliforms, Vibrio cholera and Total Streptococci. The geochemical studies reveal that there is no correlation between these parameters and the microbial population. The migration of the water from the elevated regions (urban region) is witnessed and the concentration of the microbial population is higher in these regions except in the southern region which has impermeable clay and this arrest the movement of water.

Introduction

Soils are formed by weathering of rocks and minerals and all soils contain some amount of soluble salts. Many of these act as a source of essential nutrients for the healthy growth of plants. However, when quantity and quality of salts in the soil near rhizosphere exceeds a particular value, growth, yield and/or quality of most crops is adversely affected. Such a soil is called salt-affected. The degree of adverse effects depends upon the type and quantity of salts, crop and its variety, stage of growth, cultural practices and environmental factors viz. temperature, relative humidity, and rainfall etc. Development of salinity and waterlogging is a serious problem in arid and semi-arid regions of the world and threatening the sustainability of irrigated agriculture.

Salt-affected soils occupy an estimated 952.2 million ha of land in the world that constitutes nearly 7% of the total land area and nearly 33% of the potential arable land (Dudal and Purnell, 1986). In India, the salt affected soils account for 6.727 million ha i.e. 2.1% of geographical area of the country. These soils are mostly found in the states of Uttar Pradesh, Haryana, Punjab, Madhya Pradesh, Bihar and Andhra Pradesh. In the last 25 years 1.1 million ha of alkali soils have been reclaimed in the states of Haryana, Punjab and Uttar Pradesh. These have contributed to the additional food grain production of 10 million tonnes annually. Reclamation of alkali soils have also decreased the incidents of floods and malaria and increased the groundwater recharge.

Definitions

Pathology

Pathology is the study of the anatomical, chemical and physiological alterations from normal as a result of disease in animals. It is a key subject because it forms a vital bridge between preclinical sciences (Anatomy, Physiology, Biochemistry) and clinical branches of Medicine and Surgery (Fig.1.1). Pathology is derived from the Greek word pathos = disease, logos = study. It has many branches, which are defined as under:

General Pathology

General Pathology concerns with basic alterations of tissues as a result of disease. e.g. fatty changes, thrombosis, amyloidosis, embolism, necrosis (Fig. 1.2).

Systemic Pathology

Systemic Pathology deals with alterations in tissues/organs of a particular system. e.g. respiratory system, genital system etc. (Fig. 1.3).

Plant-parasitic nematodes are important soil-borne pests that reduce crop productivity by feeding on roots and interfering with water and nutrient absorption. Temperature, soil moisture, rainfall, carbon dioxide and host-plant conditions influence their development, reproduction, survival and geographical distribution. Climate change may allow certain nematode species to expand into new regions, complete additional generations and cause greater crop damage. Drought, flooding and altered soil conditions may also modify interactions among nematodes, plants, microorganisms and natural enemies. This chapter examines the likely effects of climate change on important plant-parasitic nematodes and discusses monitoring, forecasting and adaptive management approaches for climate-resilient crop protection.

Introduction

The horticulture sector has been a driving force in stimulating a healthy growth trend in Indian agriculture. This sector contributes around 28 per cent of the GDP from about 13.08 per cent of the area and 37 percent of the total exports of the agricultural commodities (Rather et al., 2013)  India is currently producing 257.2 million tonnes of horticulture produce from an area of 23 million ha. Over the last decade, the area under horticulture grew by about 3.8% per annum but production rose by 7.6% per annum. The higher growth rate in horticulture was brought about by improvement in productivity of horticulture crops, which increased by about 28% between 2001-02 and 2011-12. (Anonymous, 2012)

Introduction

Developments in both hardware and software sectors of computer science raised high expectations and strong vision to solve number of problems in all sectors of economy. Introduction of personal computers (PC) in 1970’s created vision of paperless offices, simplified computing, automated process control, management information system, expert system etc. Initially, it had greater impact on agricultural research and development in developed countries in the form of Information and Communication Technology (ICT). Growth of companies with promises to provide specialist software to farmers and growers during 1980’s is a clear indicator of the high expectation and visualization of ICT in the field agricultural research and development. A review of agricultural software availability and use has been made by an international team in 1997 called FARMSOFT. This review covered on eight countries viz. Belgium, France, Germany, Israel, Italy, Portugal, Spain and The Netherlands. It was found that in 1996 out of 1315 software related to agriculture, 39% were in category of management, 26% were in category of animal husbandry, 8.9% in category of crop production, 7.0% in category of machinery and process control, 0.1% in category of irrigation and 19% in others category. Comparison of change in software inventory in 1996 with respect to 1994 revealed that there is around 15% growth in the agricultural software development. The higher positive growth was in the category of management software (38.40%) followed by animal husbandry (10.45%) and others (10.44%). However, highest negative growth was observed in the category of irrigation (-163.15%) followed by crop production (-53.85%) and machinery and process control (-30.95%). This indicates that overall agricultural software inventory was growing but while growth in the software related to agricultural management was sufficiently high, there was sharp decline in categories of irrigation and crop production. This change in pattern may be attributed to saturation of software and bottlenecks due to limitation of related technological innovations, socio-economic adoption and infrastructural facilities.

Introduction 
A major challenge facing the world today is making the transition to a sustainable and resource-efficient economy, especially considering climate change, resource depletion, and rising waste production. The idea of a circular economy has drawn a lot of attention in this setting. In contrast to the conventional linear economic paradigm of “take-make-dispose,” the circular economy prioritizes closed-loop solutions that reduce waste and environmental impact by reusing, recycling, and regenerating resources. The efficient use of biomass as a plentiful and renewable resource to produce biofuels, biochemicals, and bio-based products is a crucial part of this circular framework. The combination of cellulose, hemicellulose, and lignin, known as lignocellulosic biomass, is one of the most widely available and sustainable types of feedstocks for biomass. Originating from forestry byproducts, specific energy crops, and agricultural residues like corn stover and wheat straw, lignocellulosic biomass is a feasible substitute for raw materials derived from fossil fuels [1]. By minimizing reliance on non-renewable resources and supporting sustainable waste management, its conversion through biorefineries into a wide range of bio-based goods is fully in line with the concepts of the circular economy [2]. Integrated systems known as lignocellulosic biorefineries maximize resource efficiency and reduce environmental impact by converting all the components of biomass into marketable products. The production of biofuels (such as bioethanol and biodiesel), platform chemicals, bioplastics, and energy by these biorefineries greatly aids in the creation of renewable energy and sustainable industrial processes [3]. Biorefineries can maximize the utilization of biomass feedstocks by converting them into high-value products while upholding zero-waste principles by utilizing a variety of biochemical and thermochemical conversion processes [4]. A summation of the function of lignocellulosic biorefineries in promoting the circular economy is given in this chapter. The first section covers the current developments in pretreatment and conversion methods as well as the composition of lignocellulosic biomass. By incorporating these technologies into biorefinery systems, waste valorization and energy efficiency issues can be resolved, and biobased goods can be produced more effectively. This chapter also examines the prospects and problems faced by lignocellulosic biorefineries, looking at their technological, economic, and regulatory elements as well as how they might help with the worldwide transition to a circular bioeconomy.

Theophrastus gave the name “ORCHIDS” to the group of bizarre plants on the basis of the resemblance of paired underground tubers of these plants to masculine anatomy. This resemblance was also responsible for the mistaken belief that the orchids posses aphrodisiac properties and eating of underground tubers might “provoke venus” and they may be get male children. The appreciation of orchid beauty has a very long history in both the Western and Eastern cultures. Much of this is attributed to the diverse form and structure of orchids and the large number of species in the orchid family. Orchidaceae is amongst the most diverse family of the flowering plants consisting of 35,000 species under 880 genera (Kumar and Sheela, 2007, Fay and Chase, 2009). Orchids belong to the highest level of organization and are distinguished by the complicated biology of reproduction with long developmental cycle (Vakhrameeva et al., 1991, Sherif et al., 2012). They are beautiful and exotic perennial herbs grown in both north and south hemispheres. They exhibit an incredible range of diversity in size, shape and colour of flowers. Its flowers have lustrous, translucent petals rich in variegated colors and fragrances. Generally Orchids can grow at different elevations (Kumar and  Sheela, 2007).

In India, land is limited and shrinking whereas the human and animal populations are increasing. The land and man ratio has fallen rapidly in the past half century from 0.34 in 1950 to 0.14, and is projected to be 0.10 in 2025. Horticultural crops however, have shown substantial growth acceleration (Table 1).The area devoted to fruit production increased 50 per cent, while the vegetable growing area increased 20 per cent. Grape, an export crop, currently at 43,000 ha, increased by 70 per cent. The value of horticultural crops grew at an average of 7.5 percent during the 1990’s. High yield and quality in horticulture can only be ensured through rational blend of commercial fertilizers and organic nutrient sources.

The circulatory system includes the heart, blood and lymph vessels, blood, lymph, cerebrospinal and tissue fluids. Circulation of blood in the body is important for the transport of nutrients to all parts of the body and for the transport of gases and waste products. In fact most of the functions of blood could not have been possible, if there were no circulation of blood.

In order to constantly circulate the blood to all parts of the body and back, the body needs the services of an efficient pump. The pump or heart is based on the ability of muscle to contract or shorten. The blood is carried in a system of elastic tubes of pipes (arteries, capillaries and veins). The circulation of blood in the domestic animals or mammals is referred to as closed circulation because the blood returns to the heart without leaving this system of tubes.

The heartbeat frequency or pulse rate is usually given as the number of heart beats per minute. The heart rate increases several times during exercise or thermal stress. The average pulse rate of various domestic animals is given in Table 1.

Soil acidity is most conveniently measured by pH of soil suspension with water. Pure water undergoes dissociation into hydrogen and hydroxyl ions and are in equilibrium with undissiociated water molecules Thus, H2 O ??? ??? H+ + OH- (1) and in presence of another H2 O molecule, H+ converts to H3 O+ H+ + H2 O ??? ??? H3 O+ (2) Since water is a weak electrolyte and dissociates as per Eqn. 1, the ionic product of water can be written as – KW = aH+ x aOH- = (CH+ x COH– ) x ( fH+ x fOH-) (3) where, a, C, and f represents the activities, concentrations and activity coefficients of respective ions. In pure water and in dilute solutions the activity coefficients are approximately unity thus the product of concentrations of H+ and OH-1 is the ionic product of water and at ordinary temperature (250 C) this has a constant value of 10-14 gm ions per litre so, Kw =(CH+ x COH–1) = 10-14 gm ion per litre (4) such that, CH+ = COH–1 = 107 gm ion per litre Therefore, if hydrogen ion concentration of an aqueous solution exceeds this value, (10-7gm ion per litre), the solution is said to be acidic then there will be a proportionate decrease of OH- concentration to maintain the constant value of ionic product.

Any technique that uses living organisms or substances from these organisms to make or modify a product or to improve plant or animal or to develop microorganism for specific uses, can be termed biotechnology. Biotechnology involves microbes or cells derived from plants and animals for efficient production of useful products for mankind. The use of microbes for production of alcohol and penicillin, to name a few, is well known. However, in the last 25 years, several novel organisms, yielding useful products have been created by genetic engineering. Today, there is a wide application of biotechnology in human medicine, agriculture and animal husbandry in the area of diagnosis prophylaxis and therapy.

Aquaculture industry has undergone a sea change world over in the last three decades. The important needs of the industry are development of fast growing disease resistant fish and shellfish varieties, development of cheap and effective vaccines, disease diagnostics, cell lines sand probiotics. Efforts on these lines have already begun since 3-4 decades and results are highly promising. Some of the biotechnologies employed in aquaculture health management (Plate 15) are fish cell lines, monoclonal antibodies and nucleic acids for diagnostics sub unit and nucleic acid vaccines for prophylaxis, transgenes for disease resistance, gene editing in fishes and their pathogens and probiotics for bioremedial measures.

A. Cell Lines for Health Management

Cell lines are transformed cells that are adapted well to grow and multiply outside the host in in vitro culture systems. Cells lines can be developed from fast growing tissues of young fish. There are two methods of developing cell lines (1) Explant method, (2) Enzymatic method. Cell lines are grown in sterile plastic or glass containers containing appropriate medium having nutrients salts, antibiotics, buffers, serum etc. Minimum essential medium (MEM) is the common medium employed for fish cell line. Cell lines are developed, characterised and deposited in national and international repositories, which can be procured for use in research and industry.

Introduction
A plant seed consists of an embryo and reserve food material (endosperm/ cotyledon) which is surrounded by a protective seed coat. The seed ensures that the next generation of plants exists. The embryo is made up of one or two cotyledons attached to a central axis. The upper part of the axis contains a plumule at its tip. The plumule grows into the shoot system. The lower part of the axis consists of the hypocotyl and a radicle. The radicle grows into the root system. The endosperm is the food reserve that the embryo uses during the early stages of germination. Before the embryo is able to produce its own food through photosynthesis, the endosperm provides vital nutrients to the embryo. Seed stands as an essential and fundamental agricultural input. It can be characterized as a propagative entity that facilitates the continuation of species from one generation to the next. Alternatively, it can be described as a mature fertilized ovule. Seeds play multifaceted roles for their parent plants, encompassing embryo nourishment, dispersion to novel locations, and entering a state of dormancy during adverse environmental circumstances. Seeds originate from various sources like self-pollination, cross-pollination, vegetative propagation, and mechanisms such as apomixis, resulting in diverse varieties or hybrids. Maintaining the genetic consistency of cross-pollinated seeds presents notable challenges. Certain fruit crops encounter obstacles in natural seed propagation due to factors like seed heterozygosity, diminished endosperm size, or minuscule seed dimensions. Additionally, some seedless fruits cannot be propagated conventionally through seeds. Seeds frequently become susceptible to seed-transmitted diseases, facilitating the transmission of diseases across different geographical areas. These constraints in seed-based propagation have spurred the exploration of alternative techniques for species proliferation. This exploration led to the emergence of the concept of synthetic seeds within the realm of plant tissue culture. Synthetic seeds are also known as synseeds or artificial seeds or somatic seeds, seed analog, or manufactured seed. The concept of synthetic seeds has been described in various manners by different researchers. Capuano et al., (1998) defined synthetic seeds as somatic embryos that are enclosed artificially, originating from shoot buds, cell aggregates, or any suitable plant tissue for sowing purposes. These synthetic seeds are capable of developing into plants under controlled in vitro or ex vitro conditions and can maintain this potential even after prolonged storage. Another definition of synthetic or artificial seeds comes from Gray and Purohit (1991) and Redenbaugh (1993), who refer to them as somatic embryos designed for use in the commercial propagation of plants.

Introduction 
Fossils fuel resources are crucial for producing and distributing other goods, making them one of the most important global commodities. Fossil fuels account for more than 75% of total energy consumption in society. It is critical to recognize that the fossil energy problem and anthropogenic climate change problem are inextricably linked and must be addressed as two intertwined challenges requiring a comprehensive solution. The features of coal, oil and gas which are employed as fossil fuels for power generation, have different classification of characteristics (Shindell & Smith, 2019). Fossil fuels are natural fuels and derived from the decompositions, heating and pressurization, of buries phytoplankton (plants) and zooplankton (animals). Over time, these waste materials get decomposed to produce carbon rich deposits that are now used to create energy products (Holechek et al., 2022). They are essential for the synthesis of steel and polymers in addition to energy. Fossil fuels fall into three main categories: coal, oil, and natural gas (Singh et al., 2023). Biofuels are produced from plants and animals waste materials and considered as a renewable source of energy. The sources are key components to overcome the issues related to greenhouse gas emission. Due to rapid change in climatic conditions, demand of renewable energy sources has increased. There are some drawbacks for fossil fuels due to presence of high carbon footprints and environmental impacts. On the other way, biofuels offer two major benefits first they reduce carbon emissions and modify waste management method, the other paving the way for a sustainable future. The carbon neutrality of biofuels is among their most alluring features. Biofuels only release the carbon dioxide that plants consume during growth, as opposed to fossil fuels that release old, stored carbon into the atmosphere. They are an eco-friendly choice because of this balance(Jeswani et al., 2020). Bioethanol, biodiesel, and biogas are among the several types of biofuels(Esmaeili & Tamjidi, 2021). Bioethanol is used in transportation and produced by using crops like corn and sugarcane. Waste management and sustainable energy production are further enhanced by biogas after producing with the help of anaerobic digestion of organic waste and is a great source of energy for heating and power generation. We can take a comprehensive approach to sustainability, improving energy efficiency and lessening our environmental impact, by combining the production of biofuel with waste management and the use of organic fertilizers. Significance environmental benefits of biofuels include lower GHG emission, reduced dependency on the fossil fuels and better air quality. By diversifying energy sources and possibly stabilizing prices, they also lessen exposure to changes in the world's oil markets, which promotes energy security. Nonetheless, it is essential to evaluate the wider ramifications of biofuel production and make sure that its advantages exceed any potential disadvantages in order to completely match with sustainability goals(Jeswani et al., 2020).

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Importance of Traditional Foods

Traditional convenience food, or tertiary processed food, is commercially prepared food designed for ease of consumption. Products designated as convenience foods are often prepared food stuffs that can be sold as hot, ready-to-eat dishes; as room-temperature, shelf-stable products; or as refrigerated or frozen products that require minimal preparation (typically just heating).

These products are often sold in portion controlled, single serve packaging designed for portability for “on-the-go” eating. Convenience food can include products such as candy; beverages such as soft drinks, juices and milk; fast food; nuts, fruits and vegetables in fresh or preserved states; processed meats and cheeses; and canned products such as soups and pasta dishes.

Traditional Foods

Preparation of Vadagam and Appalam

Vadagam is a traditional product mostly prepared from rice flour and also sago. It is an deep fat fried product and consumed as a side dish in the meals. Papad also known as appalam or papadam in South India, is essentially a thin wafer like product, usually circular in shape rolled from a dough made out of pulse, cereals, edible vegetable oil, alkaline and mucilaginous additives. It is normally consumed in toasted or fried form. In India, papad has been associated and deeply entwined with social customs/ rituals and has been developed into culinary art.

Kidney is one of the main excretory organs of the body. By secreting urine the kidney serves as the outstanding guardian of the milieu interieur. The main functions of the kidney in the maintenance of body homeostasis are listed below.

1. Maintenance of proper osmotic concentrations.
2. Maintenance of blood volume.
3. Maintenance of ion concentration.
4. Removal of nitrogenous end products of protein metabolism primarily urea, creatinine and ammonia.
5. Removal of foreign substances and/or their metabolic end products.

Thus, kidney control the concentration of most of the constituents of body fluids. In case of birds, the primary end product of protein metabolism is uric acid instead of urea. So, the major excretory product through urine in case of birds is uric acid.

Briefly, the kidney form urine in the following way. Endowed with a relatively huge blood supply, the renal glomeruli filter about 200 litres per 24 hours of protein free fluid from the blood in human being ( ie 50-60 times the plasma volume). This filtrate, which contains the soluble non protein components of the plasma, is submitted to extensive reabsorption by the renal tubules. The relative control on the reabsorption process by the kidney, is the key mechanism by which the kidney is able to maintain the composition of the milieu interieur.

Kidney also releases several hormones like renin, erythropoietin and prostaglandins, which have the capacity to influence cells and alter their physiological processes.

Introduction

Climate change and agriculture are interrelated issues, both of which take place on a global scale. Global warming is projected to have significant impacts on conditions affecting agriculture, including fluctuation of temperature, carbon dioxide, glacial run-off, precipitation and the interaction of these factors (Sehgal et al., 2006; Kalra et al., 2008). These conditions determine the carrying capacity of the biosphere to produce enough food for the human population and for domesticated animals. The overall effect of climate change on agriculture will depend on the balance of these effects. Assessment of the effects of global climate changes on agriculture might help to properly anticipate and adapt farming to maximize agricultural production. Droughts, which have frequented different parts of India through the history, have been responsible for many famines, rural poverty and migration despite development of impressive irrigation potentials. Similarly, abnormal temperatures, high velocity winds and humidity during critical stages are known to significantly affect crop growth and development, pest incidences and epidemics, demand on irrigation resources and finally food production. Over the past few decades, the main-induced changes in the climate of the earth due to multifarious human activities linked to develop have become the focus of scientific and social attention. The predicted changes to agriculture vary greatly by region and crop. Findings for wheat and rice are reported here: The study found that increase in temperature (by about 2 ºC) reduces potential grain yield in most places. Regions with higher potential productivity (such as northern India) were relatively less impacted by climate change than areas with lower potential productivity (the reduction in yields was much smaller). Climate change is also predicted to lead to boundary changes in areas suitable for growing certain crops. (Kalra et al., 2002-2003). Reduction in yields as a result of climate change is predicted to be more pronounced for rainfed crops (as opposed to irrigated crops) and under limited water supply situations because there are no coping mechanisms for rainfall variability. The difference in yield is influenced by baseline climate. In sub-tropical environments, the decrease in potential wheat yield ranged from 1.5 to 5.8%, while in tropical areas the decrease was relatively higher, suggesting that warmer regions can expect greater crop losses.

1. Introduction
Increasing population, industrialization, and change in the human lifestyle have become the reason for the exhaustion of non-renewable energy sources, our prime energy resource. The combustion of non-renewable energy sources produces toxic pollutants such as CO2, CO, NOx, SO2, etc., and greenhouse gases CH4, CO2, and N2O which significantly contribute to global warming, environmental pollution, and health hazards. In the current scenario, we need a green energy source that does not generate toxic gases and is eco-friendly. Hence, the research is triggered towards finding alternative solutions to overcome the energy crisis. The various green energy sources are solar, wind, tidal, geothermal, hydropower, biomass, hydrogen fuel cells, etc. The major drawback of these sources is the geographical location to install the plants. In the present context, identifying an alternate energy source that is sustainable, renewable, and eco-friendly to overcome the ever-growing energy demands is crucial. Hence, bioenergy is an eco-friendly, economical, and sustainable source of energy that gratifies the contemporary development environment by utilizing the potential of renewable organic energy resources (Yin and Wang et al., 2022).
2. Biomass
The sources of biomass are agro wastes, wood wastes, aquatic wastes, municipal wastes, wet wastes, industrial wastes, forest residues, etc. Figure 1.1 illustrates various sources of biomass, such as agricultural leftovers, forestry waste, energy crops, and organic municipal waste, showcasing their potential as renewable energy resources. Biomass is the product of photosynthesis and is also a versatile renewable energy source that can be utilized for sustainable biohydrogen generation. Biomass absorbs atmospheric CO2 during its growth, leading to relatively a lower net carbon impact as compared to fossil fuels. Renewable organic resources (biomass) can be in a solid, liquid, or gaseous phase. Energy generation through the incineration of biomass has been a longstanding practice. Since the energy potential of the biomass is not extracted effectively, it leads to environmental pollution (Kumar and Fiori et al., 2024). Biomass can be converted to liquid and gaseous fuels called biofuels with significant calorific value through thermochemical and biochemical processes (Gautam et al., 2020). Biofuels are superior to fossil fuels in the context of sustainability and reduced emissions of greenhouse gases. A variety of biofuels and chemicals such as bio-ethanol, biodiesel, acetic acid, formaldehyde, etc., can be manufactured from biomass (Gautam et al., 2020). Globally, research is advancing towards replacing non-renewable fuels with biofuels. However, the transition to biofuel technique presents a challenge due to the huge space requirement for biomass. Table 1.1 illustrates the categories of biomass employed for hydrogen generation, categorized into lignocellulosic materials, algal biomass, organic waste, and energy crops.