Valorising faba bean residual biomass: Effect of farming system and planting time on the potential for biofuel production

Abstract

Research was carried out in southern Italy with the aim to assess the quality of faba bean residual biomass and its potential for biorefinery application. Faba bean is a sustainable crop, due to its ability to fix atmospheric nitrogen, and a large amount of biomass remains after harvest which can be valorised for energy production. Greenhouse and early planting are known to affect pod yield and, in this respect, even the residual biomass quality needs to be assessed. For this purpose, the effects of five planting times (i.e. the dates of transplants ranging from 27 September to 22 November at two-week interval, earlier and later than the common planting date of 25 October in Naples province) on pods yield, residual biomass, and saccharification potential were evaluated in faba bean grown in open field and in greenhouse. The third planting time resulted in the highest fruit and residual biomass yield under greenhouse, whereas the fourth was the best in open field. Harvest index was best affected by the third and fourth planting times in open field. Greenhouse grown biomass showed higher values of lignin, hemicellulose and pectin, compared to open field, whereas the opposite trend was recorded with cellulose. Lignin content showed a gradual decrease from the first to the last planting time (17.7%-13.7% biomass fraction respectively), as well as pectin (from 14.1 to 11.5% biomass fraction); conversely, cellulose increased from the first to the last planting time (from 41.1 to 48.7% biomass fraction). Glucose was the most represented monosaccharide (46.7 mol%), followed by xylose (27.4 mol%) and galactose (9.9 mol%). Overall, the potential of faba bean residual biomass for energy production was best affected by open field growing, the latest planting time and alkali pre-treatment, the latter giving the highest value of saccharification (60.7 g kg −1 h −1 compared to 27.6 relevant to hot water pre-treatment).

Plant–Rhizobium symbiosis, seed nutraceuticals, and waste quality for energy production of Vicia faba L. as affected by crop management

“…Contents of cellulose, hemicellulose, pectin, crystalline cellulose, and non-cellulosic monosaccharide were performed in compliance with a previous study [25], as reported in the following. Holocellulose was determined by delignification of biomass dry powder (7.5 g) for 3 h at 75 °C in a mixture (240 mL water, 0.75 mL glacial acetic acid and 2.25 g sodium chlorite) to which further acid and chlorite amounts, equal to previous, were hourly added.…”

Joint Selenium–Iodine Supply and Arbuscular Mycorrhizal Fungi Inoculation Affect Yield and Quality of Chickpea Seeds and Residual Biomass

“…The positive effect of AMF application on plant nutritional value may become very important in combination with Se and I biofortification. In this respect, no reports in the literature regard the biochemical characteristics of crop wastes, legumes wastes in particular, with the latter being known as a significant source of energy, fiber, protein, antioxidants, and fatty acids [32][33][34][35].…”

Production system effects on growth, pod yield and seed quality of organic faba bean in southern Italy

“…In this respect, Ellis et al (1988) found that optimal flowering progress occurs at 19.9-25.4°C, or even at lower temperature with some genotypes. Due to these requirements, faba bean crop cycle starts in autumn in mild climate areas and in spring in cooler ones, but the optimal planting time for maximizing earliness, yield and quality is strictly matched to the growing environment (Myers et al, 1982;Gomez et al, 2017). In this regard, in Pakistan, Khalil et al (2010) reported that the highest yield is favored by early October sowing, compared to late summer or midautumn planting, and Fasheun and Balogun (1992) detected the significant correlation between dry matter production and radiation use efficiency as affected by planting time.…”