Fiber composition of 190 novel energy cane genotypes and their potential for biorefinery applications

This chapter examines the progressive role of sugarcane in sustainable biofuel production, highlighting the distinctions between first-, second-, and third-generation (1G, 2G, and 3G) ethanol. First-generation ethanol is derived from the fermentation of sugars in sugarcane juice, but this method is constrained by limited productivity and a tradeoff between sucrose and fiber content. Sec-ond-generation ethanol improves upon this by utilizing lignocellulosic residues such as bagasse and straw, enhancing energy yield per hectare without expanding land use. However, it requires complex pretreatment and enzymatic hydrolysis processes. Advances like deep eutectic solvents, mechanocatalysis, and engineered microbes are improving the feasibility of 2G ethanol. The third-generation approach targets non-food biomass sources such as marine algae and enhanced energy cane varieties, which offer high fiber content and adaptability to marginal environments. These 3G technologies promise carbon-neutral fuel but remain chal-lenged by high costs, energy-intensive hydrolysis, and the need for optimized microbial fermentation of diverse sugars. Energy cane emerges as a key transitional crop, offering superior yields (up to 180 tons per hectare), greater stress tolerance through robust rhizome systems, and multi-cycle productivity, thereby lowering operational costs and supporting bioelectricity co-generation. While 1G ethanol is well-established and 2G is commercially emerging, 3G holds the most transformative potential by addressing food security concerns, maximizing biomass conversion, and aligning with low-carbon economic goals. Ultimately, energy cane acts as a vital “green necklace” connecting traditional and future biofuel strategies, reinforcing Brazil’s potential leadership in global renewable energy transitions.

Chemical composition and physical properties of dew- and water-retted hemp fibers

Miscanthus clones for cellulosic bioethanol production: Relationships between biomass production, biomass production components, and biomass chemical composition

This study explores the genetic diversity, biochemical composition and trait associations in maize (Zea mays L.) to assess its potential as a dual-purpose crop for food and biofuel production. Significant variations in lignocellulosic traits among the evaluated genotypes indicate opportunities for enhancing bioethanol yields. A comparative biochemical study reveals the cellulose content in the kernel is 2.15 times higher than in stover, whereas the hemicellulose and lignin content in stover are 4.6 times and 5.3 times higher, respectively, compared to the kernel. The inbred lines DQL 2159, DQL 222-1-1 and DQL 2272 exhibited significantly higher cellulose contents of 37.05 %, 35.98 % and 35.53 %, respectively, along with significantly lower lignin contents of 20.65 %, 22.25 % and 22.53 % in maize stover. Correlation analysis shows that shoot dry weight (rp = 0.29), stalk diameter (rp = 0.33) and plant height (rp = 0.48) are positively associated with biomass yield. Biochemical studies reveal a strong negative correlation (rp = -0.59) between kernel lignin and kernel cellulose content, indicating that higher cellulose leads to lower lignin. This finding is valuable for selecting high-cellulose, low-lignin genotypes. Path coefficient analysis further identifies plant height, number of leaves per plant, stalk diameter and kernel cellulose content as key contributors to grain yield, suggesting that selection for these traits could enhance biofuel production. Identifying desirable traits that enhance biofuel efficiency, such as high cellulose and low lignin content, enables targeted breeding for improved biomass conversion. Cluster analysis revealed that Cluster III exhibited superior performance across the majority of traits evaluated, making it the most promising group for utilization in biofuel breeding programs. Notably, genotypes such as DQL 2037, DQL 2272, DQL 2159 and DQL 222-1-1 emerge as promising candidates for biofuel applications due to their high grain and stover yields, alongside elevated cellulose and hemicellulose content. Collectively, these findings provide a comprehensive framework for targeted breeding strategies aimed at developing high-yielding, biofuel-efficient maize cultivars for climate smart agriculture systems.

The study aim to evaluate the biomass quality attributes of elephant grass [ Cenchrus purpureus (Schumach.) Morrone] genotypes for the bioenergy production compared to other feedstocks. There were evaluated 32 feedstocks among them 16 elephant grass (EG) genotypes and 14 other feedstocks with potential for bioenergy applications. The evaluated quality attributes are the elemental composition, net calorific value, cellulose, hemicellulose, lignin and ash contents (% of dry matter). Our results point out that the EG genotypes show similar quality atrributes among themselves, except to the ash content. The mean net calorific value of the EG biomass (3,995 kcal kg -1 ) was superior than the rice husk and sorghum, and similar compared to sugarcane straw and bagasse, coconut fiber, energy cane, cassava waste and corn stover. The EG genotypes cellulose mean content (36%) was superior than cassava waste sample, but similar compared to all other feedstocks, except to the eucalyptus, rice husk, bamboo and sugarcane bagasse. The EG genotypes hemicellulose mean content (29.3%) was superior than the coconut husk, bamboo, cassava waste, coconut fiber, rice husk, eucalyptus and M. caesalpiniaefolia and similar to sorghum, energy cane, sugarcane straw and bagasse. The EG genotypes lignin mean content (8.2%) was superior to corn stover and similar to energy cane, sorghum, sugarcane bagasse and straw. The EG Madeira showed the lowest ash contents (2.21%) among the EG genotypes. The mean ash content of the other EG biomass (4.96%) was similar to bamboo, energy cane, cassava waste and sugarcane straw.

Biofuels produced from non-food lignocellulosic feedstocks have the potential to replace a significant percentage of fossil fuels via high yield potential and suitability for cultivation on marginal lands. Commercialization of dedicated lignocellulosic crops into single biofuels, however, is hampered by conversion technology costs and decreasing oil prices. Integrated biorefinery approaches, where value-added chemicals are produced in conjunction with biofuels, offer significant potential towards overcoming this economic disadvantage. In this study, candidate lignocellulosic feedstocks were evaluated for their potential biomass and silica yields. Feedstock entries included pearl millet-napiergrass (“PMN”; Pennisetum glaucum [L.] R. Br. × P. purpureum Schumach.), napiergrass (P. purpureum Schumach.), annual sorghum (Sorghum bicolor [L.] Moench), pearl millet (P. glaucum [L.] R. Br.), perennial sorghum (Sorghum spp.), switchgrass (Panicum virgatum L.), sunn hemp (Crotalaria juncea L.), giant miscanthus (Miscanthus × giganteus J.M. Greef and Deuter), and energy cane (Saccharum spp.). Replicated plots were planted at three locations and characterized for biomass yield, chemical composition including hemicellulose, cellulose, acid detergent lignin (ADL), neutral detergent fiber (NDF), crude protein (CP), and silica concentration. The PMN, napiergrass, energy cane, and sunn hemp had the highest biomass yields. They were superior candidates for ethanol production due to high cellulose and hemicellulose content. They also had high silica yield except for sunn hemp. Silica yield among feedstock entries ranged from 41 to 3249 kg ha−1. Based on high bioethanol and biosilica yield potential, PMN, napiergrass, and energy cane are the most promising biorefinery feedstock candidates for improving biofuel profitability.

A better understanding of sugarcane and energy cane (Saccharum spp.) in biomass accumulation and carbohydrate composition can improve the knowledge of crop production sustainability and optimal utilization. The objectives of this study were to identify sugar composition and concentrations of stalk juice in sugarcane and energy cane grown on two sandy soils during ripening and to determine differences between the two types of canes in nonstructural and structural carbohydrate partitioning and concentrations in dry biomass for the mature plant-cane, first-ratoon, and second-ratoon crops. A field study was conducted at two locations with mineral (sand) soils in south Florida, USA, using two commercial sugarcane cultivars of CP 78-1628 and CP 80-1743 and two energy cane genotypes (US 78-1013 and US 84-1066) to determine their biomass yields and carbohydrate composition and concentrations. Averaged across the three crops and two locations, energy cane had significantly higher biomass yield, lower nonstructural carbohydrate (reducing sugars and sucrose) concentrations, and higher concentrations of cellulose, hemicelluloses, and lignin than sugarcane. Although there were no differences between sugarcane and energy cane in total carbohydrate concentration (839 to 842 g kg−1 DW), energy cane had 80% higher cellulose, 63% higher hemicelluloses, and 76% higher lignin; 69, 64, and 56% lower sucrose, glucose, and fructose concentrations, respectively, than sugarcane, when averaged across the three crops and two locations. These results can be useful for potential use of canes for both sucrose and cellulosic ethanol production on marginal sand soils to improve sustainability and profitability in the future.

Core Ideas Energy cane may be an alternative crop on sand soils in the future to improve profits. It is unclear if energy cane differs from sugarcane in physiology and yield on sand soils. Energy cane had 26 to 35% greater normalized difference vegetation index and 21% higher yield than sugarcane. Increased yield of energy cane was associated with great normalized difference vegetation index and high stalk population rather than leaf net photosynthetic rate. A growing interest of producing sugarcane (a complex hybrid of Saccharum spp.) for both sugar and bioenergy and saturation of using organic soils provide an opportunity to expand production on mineral (sand) soils. However, sugarcane yields and profits on sand soils are generally low. Energy cane may be an alternative on sand soils in the future to improve profits. The objective of this study was to identify physiological and biomass traits of sugarcane and energy cane growing on sand soils. Two commercial sugarcane cultivars and two energy cane clones were planted at two sites with sand soils in southern Florida. Data were collected on plant‐cane, first‐ratoon, and second‐ratoon crops. Leaf relative chlorophyll level (SPAD), photosynthetic rate (Pn), and canopy reflectance were measured during tillering and grand growth. Normalized difference vegetation index (NDVI) was calculated based on canopy reflectance data. Stalk population, diameter and length, and aboveground biomass yields were determined when plants reached maturation. Although there were no consistent differences between sugarcane and energy cane in leaf SPAD, Pn or NDVI of plant cane, energy cane had 26 to 35% greater NDVI values than sugarcane in the ratoon crops. Energy cane showed 21% higher dry biomass than sugarcane, averaged across sites and crops. Increased biomass production of energy cane was mainly associated with high stalk population, long stalk, and great NDVI rather than leaf Pn or stalk diameter. The findings of this study on physiological parameters of energy cane vs. sugarcane can be useful for improvement of knowledge and future research.

Shade effect on carbohydrates dynamics and stem strength of soybean genotypes

Bioenergy related land use change would likely alter biogeochemical cycles and global greenhouse gas budgets. Energy cane (Saccharum officinarum L.) is a sugarcane variety and an emerging biofuel feedstock for cellulosic bio-ethanol production. It has potential for high yields and can be grown on marginal land, which minimizes competition with grain and vegetable production. The DayCent biogeochemical model was parameterized to infer potential yields of energy cane and how changing land from grazed pasture to energy cane would affect greenhouse gas (CO2, CH4 and N2O) fluxes and soil C pools. The model was used to simulate energy cane production on two soil types in central Florida, nutrient poor Spodosols and organic Histosols. Energy cane was productive on both soil types (yielding 46–76 Mg dry mass⋅ha−1). Yields were maintained through three annual cropping cycles on Histosols but declined with each harvest on Spodosols. Overall, converting pasture to energy cane created a sink for GHGs on Spodosols and reduced the size of the GHG source on Histosols. This change was driven on both soil types by eliminating CH4 emissions from cattle and by the large increase in C uptake by greater biomass production in energy cane relative to pasture. However, the change from pasture to energy cane caused Histosols to lose 4493 g CO2 eq⋅m−2 over 15 years of energy cane production. Cultivation of energy cane on former pasture on Spodosol soils in the southeast US has the potential for high biomass yield and the mitigation of GHG emissions.

Energy cane is a specialized sugarcane (Sacharum spontaneum L.) hybrid developed for high lignocellulosic biomass for biofuel production. The optimum planting spacing for energy cane is not known; hence, it has been planted with sugarcane planting spacing. We examined the effect of six plant spacings derived from three inter‐ (1.22, 1.52, and 1.83 m) and two intra‐row (0.61 and 0.91 m) spacings on energy cane growth, physiology, and biomass yield. Energy cane was planted in fall 2012, was harvested after establishment in 2013, and was allowed to ratoon for biomass yield in 2014 and 2015. The plant spacing had varied effects on energy cane growth and physiology, but no effect on biomass yield. Wide spacing resulted in increased tiller and leaf numbers, but spacing had no effect on other growth and physiological parameters at the p < 0.05 level. The results suggested that energy cane possesses the ability to adjust plant growth according to plant spacing without compromising its biomass yield and can effectively use wide spacing (1.83 × 0.91 m) commonly adopted for sugarcane planting. Wide spacing can reduce seeding cost and energy during planting and will allow the use of existing sugarcane farm machinery for energy cane production. The high biomass yield (18.8–25.1 Mg ha−1) of energy cane obtained in this study also suggests that energy cane can be successfully produced for lignocellulosic feedstock.

Biomass composition of two new energy cane cultivars compared with their ancestral Saccharum spontaneum during internode development

In order to ensure the global competitiveness of the Pulp and Paper Industry in the Southeastern U.S., more wood with targeted characteristics have to be produced more efficiently on less land. The objective of the research project is to provide a molecular genetic basis for tree breeding of desirable traits in juvenile loblolly pine, using a multidisciplinary research approach. We developed micro analytical methods for determine the cellulose and lignin content, average fiber length, and coarseness of a single ring in a 12 mm increment core. These methods allow rapid determination of these traits in micro scale. Genetic variation and genotype by environment interaction (GxE) were studied in several juvenile wood traits of loblolly pine (Pinus taeda L.). Over 1000 wood samples of 12 mm increment cores were collected from 14 full-sib families generated by a 6-parent half-diallel mating design (11-year-old) in four progeny tests. Juvenile (ring 3) and transition (ring 8) for each increment core were analyzed for cellulose and lignin content, average fiber length, and coarseness. Transition wood had higher cellulose content, longer fiber and higher coarseness, but lower lignin than juvenile wood. General combining ability variance for the traits in juvenile wood explained 3 to 10% ofmore » the total variance, whereas the specific combining ability variance was negligible or zero. There were noticeable full-sib family rank changes between sites for all the traits. This was reflected in very high specific combining ability by site interaction variances, which explained from 5% (fiber length) to 37% (lignin) of the total variance. Weak individual-tree heritabilities were found for cellulose, lignin content and fiber length at the juvenile and transition wood, except for lignin at the transition wood (0.23). Coarseness had moderately high individual-tree heritabilities at both the juvenile (0.39) and transition wood (0.30). Favorable genetic correlations of volume and stem straightness were found with cellulose content, fiber length and coarseness, suggesting that selection on growth or stem straightness would results in favorable response in chemical wood traits. We have developed a series of methods for application of functional genomics to understanding the molecular basis of traits important to tree breeding for improved chemical and physical properties of wood. Two types of technologies were used, microarray analysis of gene expression, and profiling of soluble metabolites from wood forming tissues. We were able to correlate wood property phenotypes with expression of specific genes and with the abundance of specific metabolites using a new database and appropriate statistical tools. These results implicate a series of candidate genes for cellulose content, lignin content, hemicellulose content and specific extractible metabolites. Future work should integrate such studies in mapping populations and genetic maps to make more precise associations of traits with gene locations in order to increase the predictive power of molecular markers, and to distinguish between different candidate genes associated by linkage or by function. This study has found that loblolly pine families differed significantly for cellulose yield, fiber length, fiber coarseness, and less for lignin content. The implication for forest industry is that genetic testing and selection for these traits is possible and practical. With sufficient genetic variation, we could improve cellulose yield, fiber length, fiber coarseness, and reduce lignin content in Loblolly pine. With the continued progress in molecular research, some candidate genes may be used for selecting cellulose content, lignin content, hemicellulose content and specific extractible metabolites. This would accelerate current breeding and testing program significantly, and produce pine plantations with not only high productivity, but desirable wood properties as well.« less

Lignin and hemicelluloses are the major impurities to be removed in natural fibers for it to be suitable in composite application and other uses. This research is based on evaluating the influence of soaking time and sodium hydroxide concentration on the chemical composition of treated mango seed shell (MSSF) by immersing the MSSF in NaOH solution at concentration of 2.5 - 7.5 wt % and soaking time of 2-6 hr, in order to decrease the lignin and hemicellulose content while increasing its cellulose content. The optimum conditions obtained for concentration and soaking time of NaOH were 6.09 % and 5.22 hr, respectively. At these conditions, cellulose content was increased to 94.8002%, while the hemicelluloses and lignin content were reduced to 2.2779% and 0.508502%, respectively. The process parameter of MSSF was optimized using central composite design (CCD) to predict the cellulose, hemicelluloses, and lignin content. The quadratic model of response surface model (RSM) was adopted for the prediction of cellulose, hemicelluloses, and lignin content. The maximum error between the predicted using CCD and experimental results was less 0.38%. These errors in variation for both the predicted by the RSM and the actual gave good alignment with both results. Therefore, at these treatment conditions, MSSF can be utilized for composite application and other industrial purpose. Keywords : NaOH, Chemical Modification, Mango Seed Shell Flour, Chemical Composition

Energy cane (Saccharum spp.) is an alternative for biomass production to meet demands for high yield and fiber content feedstock for bioenergy production. However, there is limited research data and information available for this crop that was recently introduced in Brazil. The focus of this study was to evaluate the biomass production and mineral composition of energy cane genotypes to understand their productivity and define nutrient management practices according to nutrient removal. The experiment was conducted in northeastern Brazil during plant cane and first ratoon crop cycles and evaluated six energy cane and one sugarcane (cultivar most grown in the region) genotype. Depending on genotype and crop cycle, energy cane dry biomass production ranged from 43 to 63 Mg ha−1 and was greater than that of sugarcane, ranging from 25 to 51 Mg ha−1. Energy cane allocated a greater amount of dry biomass in dry leaves and tops than sugarcane. Overall, 1 Mg of fresh energy cane required 1.5 kg of N, 0.32 kg of P, 5.1 kg of K, 0.6 kg of Mg, 0.5 kg of S, 5.7 g of B, 1.4 g of Cu, 6.3 g of Mn, and 4.7 g of Zn. Macronutrient removal by some energy cane genotypes was higher than that by sugarcane due to greater biomass production. Energy cane has the potential for greater dry biomass production than sugarcane, but it also removes a larger amount of nutrients. The recommendation of an amount of nutrients needed for energy cane production is a key issue for the establishment of this crop as a raw material for bioenergy production in Brazil.