The leaves ofthe agave plant are left in the field after harvesting the heads for tequila production. Different types ofagave leaves were isolated, classified, and their content in the total plant determined. The usable fractions were collected and their properties determined. Of the total wet weight of the agave plant, 54% corresponds to the agave head, 32% corresponds to materials which could be usable for sugar and fiber production which leaves 14% ofthe wet plant without apparent utility. The fractions with higher total reducing sugars (TRS) content were the fresh fraction of partially dry leaves stuck to the head and the leaf bases with a TRS content of 16.1% and 13.1%, respectively. The highest TRS concentration (16-28%) is in the agave head which is used for tequila production. Theleaves are 90-120 cm longand 8-12 cmwide andcontain fiberbundles that are 23-52cm long and 0.6-13mm wide. The ultimate fiber length is approximately 1.6 mm with an average width of25 µm. There are several types ofleaffibers that can be utilized depending on what part ofthe plant they come from and what product is desired. Agave leaffibers were pulped using a soda pulping process and the pulp was hand formed into test sheets. Test sheets made from pulped agave leaffibers had a breaking length comparable to paper made from both pine and eucalyptus fibers, but the tear index and burst index were lower than the other two papers.

Biosynthesis of poly(3‐hydroxybutyrate) (PHB) from raw starch as the carbon source by the polysaccharide‐digesting bacteria Saccharophagus degradans was investigated in a fed‐batch culture. The production and properties of the PHB synthesized from starch were compared to those obtained using glucose as carbon source. In fed‐batch cultures, S. degradans accumulated 21.35 and 17.46% of PHB, using glucose or starch as carbon source, respectively. The physical properties of the biopolymer produced from each carbon source were similar between them. Molecular mass, melting temperature and heat of fusion were 54.23 kDa, 165.61°C and 59.59 J/g, respectively, using glucose; and 57.07 kDa, 174.31°C and 67.66 J/g, respectively, using starch. This is the first work describing the capability of S. degradans to utilize raw starch as the sole carbon source for the production of PHB.

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This paper reports on mechanical properties and natural durability of avocado branch wood (Persea americana Mill.) with the objectives of providing a reliable property profile and to promote the rational use of this abundant yet largely neglected natural resource.  The mechanical properties (static bending, compression, shear, impact bending) and hardness were determined in accordance with European standards (CEN). Natural durability was assessed according to the European standard EN 350-1 (agar block test) using the white rot fungi Trametes versicolor and Phanerochaete chrysosporium, and the brown rot fungus Postia placenta. Avocado trees yield a low to medium density (0,44-0,54-0,64 g/cm3 at 12% mc) branch wood with below average strength under static bending, compression and tension parallel to the grain and average values for longitudinal shear, impact bending and hardness. The wood is rated non-resistant (class 5 according to EN 350-1) and thus is not suitable for exterior applications unless treated. Considering its property profile and the small dimensions available, avocado wood is recommended for general carpentry, furniture, interior paneling, glue-boards for closets and cabinets, and glue-lams for indoor framework.

Se realizó un análisis químico del duramen de Andira inermis para determinar los principales componentes químicos. Los resultados encontrados fueron: pH de 5.9, 0.71 % de sustancias inorgánicas, 19.1 % de sustancias extraíbles, 34.2 % de lignina y 65.78 % de polisacáridos. En las cenizas se detectó la presencia de calcio, magnesio, azufre y silicio. Las sustancias fueron obtenidas mediante extracción sucesiva con ciclohexano, cloroformo, acetona y metanol en equipo Soxhlet y finalmente con agua caliente bajo reflujo. La solubilidad del duramen fue mayor en acetona (8.6 %) y en metanol (5.3 %); el contenido total de sustancias extraíbles fue de 19.1 %.