Amino acid composition of humic acid-like polymers produced by streptomycetes and of humic acids from pasture and arable land

Composted versus Raw Olive Mill Waste as Substrates for the Production of Medicinal Mushrooms: An Assessment of Selected Cultivation and Quality Parameters

“…Although this latter type of material provides readily assimilated forms of nutrients whose impacts are easily identifiable on the performance of the subsequent mushroom crop, at the same time its use presents significant drawbacks as previously explained. In contrast, a TPOMW-based cultivation medium maintains most of the inherent advantageous properties of a typical plain lignocellulosic substrate for the selective growth of mushroom species [59]. Since it possesses a rather high content in complex organic compounds, it provides a very important competitive advantage for the cultivated mushroom, especially under commercial cultivation conditions.…”

Formation of Humic-like Substances in Mixed and Pure Cultures of Aquatic Microorganisms

“…By comparison, aquatic HS ranged between 30 and 50 %. * Aromaticity calculated from specific absorbance at 280 nm according to [17]. The FTIR spectra of the microbial HS were similar to that of the aquatic HS but some additional bands appeared (Fig.…”

“…The From the elemental analysis of the microbial HS, high H/C and N/C ratios were calculated, which indicate the predominance of aliphatic and proteinous structural units. For humic acid-like polymers produced in cultures of streptomycetes it has been found that 40 % of the total nitrogen exists as NH 4 +and amino acid-N [17]. Also Visser [18] reported higher hydrogen and nitrogen contents in HA produced from microbial substrates compared to those of aquatic and terrestrial origins.…”

“…The data in Table 6 show that the isotopic composition of the microbial biomass and humic acids differs not only for the individual microorganisms but also for the organic substrate used as the C and N source. With B. sphaericus, e.g., both the * Aromaticity calculated from specific absorbance at 280 nm according to [17]. biomass and humic acids became isotopically heavier than the substrates, irrespective of the individual substrate quality.…”