Biogenic residues

Hoogwijk et al. (2005) assume the biomass energy potential in Western Europe from energy crops, agricultural residues, forest residues and industrial biogenic residues to be of the order of 10000 PJ/year and 16000 PJ/year by 2050. The analysis is based on the IMAGE 2.2 model using the four scenarios from the Special Report on Emissions Scenarios (SRES), (Nakicenovic, 2000) as main assumptions for the included food demand and supply. 

Besides the lignoceUulosic residues described in Section 4.2.2.4 further biogenic residues accrue. 

Since fossil raw materials are becoming scarce, biogenic residues are more and more not only a topic of disposal but also of utilization. A civilization biorefinery defines a system for the fullest possible and efficient utilization of such bioresources for energetic and substantial application purposes. The civilization biorefinery is still a vision today, but examples exist, which demonstrate their potential and steps into realization Section 4.3. ... 

Figure 8.8 The bioliq plant at KIT In a multistage process, high-quality synthetic fuels are produced from straw and other biogenous residues. (Photograph KIT/Tom Zevaco.)...

Numerous site-directed mutagenesis studies have provided a conclusive picture for the molecular interactions between the receptor-activating biogenic amines (e.g. serotonin, epinephrine, dopamine) and their receptors [23-27] a highly conserved aspartate residue in transmembrane (TM) helix TM3 (Asp 3.32 according to the Ballosteros-Weinstein nomenclature) [28], conserved serine residues in TM5 (e.g. 

We may differentiate between direct conversion of biomass into bioenergy (electricity and heat, solid fuels from biogenic wastes and residues, biogas, etc.) and biofuels. Catalysis has a minor role in the first case but is a critical element in the production of biofuels. However, notably, there are also potentially interesting developments related to bioenergy. 

Krahn et al. [479] developed a similar multi-residue scheme for the determination of organochlorines and PAHs in sediments. In this scheme, the preparation is semi-automated with GPC to separate the biogenic material and the sulfur from both the PAHs and organochlorines in the samples. The sterols were separated and purified with an amino-cyano HPLC column prior to derivatiza-tion with bis(trimethylsilyl)trifluoroacetamide (BSTFA). 

In the method(s), petroleum constituents are extracted into a suitable solvent. Biogenic polar materials typically may be partially or completely removed with silica gel. The solvent is evaporated and the residue is weighed. This quantity is reported as a percentage of the total soil sample dry weight. These methods are better suited for heavy oil because they include an evaporation step. 

The chemical weathering of crustal rock was discussed in Chapter 14 from the perspective of clay mineral formation. It was shown that acid attack of igneous silicates produces dissolved ions and a weathered solid residue, called a clay mineral. Examples of these weathering reactions were shown in Table 14.1 using CO2 + H2O as the acid (carbonic acid). Other minerals that undergo terrestrial weathering include the evaporites, biogenic carbonates, and sulfides. Their contributions to the major ion content of river water are shown in Table 21.1. 

In addition to the 20 proteinogenic amino acids (see p. 60), there are also many more compounds of the same type in nature. These arise during metabolic reactions (A) or as a result of enzymatic modifications of amino acid residues in peptides or proteins (B). The biogenic amines (C) are synthesized from a-amino acids by decarboxylation. 

Acyl residues are usually activated by transfer to coenzyme A (2). In coenzyme A (see p. 12), pantetheine is linked to 3 -phos-pho-ADP by a phosphoric acid anhydride bond. Pantetheine consists of three components connected by amide bonds—pantoic acid, alanine, and cysteamine. The latter two components are biogenic amines formed by the decarboxylation of aspartate and cysteine, respectively. The compound formed from pantoic acid and p-alanine (pantothenic acid) has vitamin-like characteristics for humans (see p. 368). Reactions between the thiol group of the cysteamine residue and carboxylic acids give rise to thioesters, such as acetyl CoA. This reaction is strongly endergonic, and it is therefore coupled to exergonic processes. Thioesters represent the activated form of carboxylic adds, because acyl residues of this type have a high chemical potential and are easily transferred to other molecules. This property is often exploited in metabolism. 

Alkaloids with the piperidine nucleus, such as pelletierine (Punica grana-tum), lobelanine Lobelia inflata) and piperine Piper nigrum), have a typical biosynthesis pathway. It starts with L-lysine and continues via cadaverine (biogenic amine), A -piperideine and A -piperidinium cations and lobelanine, to be synthesized as lobeline. Piperine is synthesized from A -piperideine via piperidine (Figure 49). For the transformation from A -piperideine to A -piperideine cation, the residue from acetyl-CoA is needed, together with SAM activity in the transformation to lobelanine. Piperine is synthesized from piperidine through the formation of amide. 

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