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Pyroligneous acid also called wood vinegar is an aqueous liquid produced from pyrolysis of lignocellulose waste and biomass. In general, the pyrolysis types are classified base on heating rate mainly either fast or slow pyrolysis. The characteristic and properties of wood vinegar are primarily influenced by the type of carbonaceous feedstocks as well as the production techniques. Wood vinegar is a complex mixture of polar and non-polar chemicals with various molecular weights and compositions. Its major constituent is water (80-90%). Some physical properties; such as pH, specific gravity, dissolved tar content are, respectively, within the range of 2-4, 1.005-1.016 g/mL, 0.23-0.89% wt, and color, odor and transparency have been reported. In addition, the degree of o Brix was ranged between 1.7 and 6.6. Besides water, the chemical compositions of wood vinegars consisted of acetic acid with the largest component (30.45-70.60 mg.mL À1). A high number of phenol derivatives have been found and those in higher concentrations were 4-propyl-2-methoxyphenol (5-11 mg.mL À1) followed by 2-methylphenol (2-4 mg.mL À1). Wood vinegar has been regarded as a natural product, which claimed to be capable in several fields of application. In agriculture, wood vinegar has been used in vegetable cropping in order to combat disease, pest control, improve growth and fruit quality, seed germination accelerator as well as herbicide. In pharmaceutical and medical applications, it is used for the preparation of detoxification pad while in veterinary and animal production, incorporation of the wood vinegar in feed could promote acidity in large intestine to inhibit growth of enteropathogenic microbes. In food processing, wood vinegar has a characteristic smoke flavor, and also exhibits microbial growth inhibition. In addition, several investigators reported that bio-oil and wood vinegar obtained from fast pyrolysis and carbonization showed a high potential on organic wood preservative. In summary, the wood vinegar prepared from the tropical wood and/or biomass waste is widely beneficial. The chapter attempts to provide essential knowledge relevant to physicochemical characteristics of wood vinegar and its applications.

Lack of dosing information of the major antibiotics known as oxytetracycline (OTC) for the Pacific white shrimp (Litopenaeus vannamei) could have harmful impact on aquaculture in Thailand. The aim of this study was to detail complete pharmacokinetic information of OTC in the Pacific white shrimp. Sixty-four male L. vannamei weighing 14-22 g with carapace length of 2.30-3.00 cm in the standardized moulting stage of C-D(0) were used for the investigations. Single dose, 10 microg/g body weight OTC solution was administered intra-sinusally (i.s.), and the shrimps were then sampled in three replicates at time intervals of 0.25, 0.5, 2, 4, 6, 9, 12, 24, 48, 72, 170, 336 and 504 h postdose. OTC levels with time intervals in biological matrices including the hemolymph, abdominal muscle, and digestive gland of each sample were determined by validated high-performance liquid chromatography, and were analyzed with noncompartment and compartment models. A simplified two-compartment model was employed rather than a more complicated model, with additional digestive compartment if necessary. A significant portion of the OTC was found in the digestive glands, even though the OTC was administered i.s. The model indicated that the OTC was thus not only distributed into the tissue compartment, but also to the digestive gland, from where it was eliminated from the shrimp's body. The dispositional half-lives of all compartments was found to be 14-21 h. Approximately 60% of the drug elimination took place in digestive gland, which is proposed to be the major route of elimination.

Abstract. Neutral lipid and phospholipid fractions and their component lipid classes in the digestive gland, abdominal muscle, epidermis and cuticle of Penaeus esculentus Haswell were analysed and compared during the moulting cycle and during starvation. The prawns were collected from Moreton Bay, Queensland, Australia, by trawling during [1985][1986][1987], and were fed on a standard, semi-purified diet.The digestive gland appears to be a major site of lipid synthesis, storage and mobilisation in preparation for moulting. Neutral lipid, 59 to 80% of which was triacylglycerol, was the larger fraction. It accumulated during early premoult, mainly due to the increase in triacylglycerol. The digestive gland contained only 18% of the total body lipid, or 8% of body lipid as triacylglycerol. Thus, the reserve lipid available for energy production is very small. Digestive gland triacylglycerol was markedly depleted after 4 d starvation and was almost completely absent after 8 d. In the other tissues, the major fraction was phospholipid, of which over 50% was phosphatidylcholine and up to 20% phoshatidylethanolamine; cholesterol was the major class in the neutral lipid fraction and appeared to be very stable. Most of this lipid was probably a component of cellular membranes. The lipid composition of muscle changed very little during the moulting cycle: total lipid levels in the epidermis were high in late premoult and early postmoult, when new cuticle is being secreted, but the proportions of the component lipids were closely similar. Cuticle lipid, together with other major components, was resorbed from the old cuticle prior to ecdysis, but the cuticle phospholipids appeared to be labile at all moult stages. The total of all lipids in fed P. esculentus was about 3.6% dry weight, of which about 70% was phospholipid. Earlier research had shown that when digestive gland lipid is exhausted after a short period of starvation, muscle is metabolised for energy. The present research showed that in the remaining muscle only about 13% of * Present address: Department of Biochemistry, Faculty of Science, Prince of Songkla University, P.O. Box 3, Kho Hong, Songkla 90112, Thailand lipid was lost after 21 d starvation, mostly as phosphatidylcholine. This is in keeping with the need to maintain this tissue in a functional state. In contrast, epidermal lipid levels were markedly reduced after only 4 d starvation and the proportions ofphospholipids changed significantly. This sensitivity of the cuticle lipids to starvation may be the cause of delayed moulting, which is characteristic of poor nutrition.

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