Saldanha Bay,South Africa: recovery of Gracilaria verrucosa (Gracilariales,Rhodophyta)

Since World War II the greater Saldanha Bay lagoon system, South Africa, has been an important Gracilaria producer. Two agar factories, built in the 1960's, used Gracilaria from Saldanha Bay as their raw material. In the early 1970's the industry was destroyed as a result of dredging and marine construction operations to establish a harbor in the bay for loading ore. These environmental changes destroyed stocks and prevented the previously significant beachings of the seaweed from occurring. After a few years of no or very low commercial production, the resource slowly started to recover. The size of Gracilaria drifts increased over the following eight years to approximately one-third of the original output. This trend seems to continue. Although the stocks and resultant drifts are unlikely to recover fully to their original quantity, current production is already sufficient to ensure re-establishment of a seaweed industry in Saldanha Bay. This could have considerable socio-economic impact on the area.     

Resource utilization conditions as biochar of an invasive plant Spartina alterniflora in coastal wetlands of China

Converting feedstocks of invasive plants into biochar is a new and cost‐effective measure for their control, and benefits for the sustainable development of native ecosystems. Spartina alterniflora, an invasive plant widely distributed in coastal wetlands of China, was used to produce biochar. We aimed to analyze how S. alterniflora biochar properties changed with desalination of feedstocks, pyrolysis temperature, and residence time. Results showed that desalting feedstocks increased biochar pH, stability, porosity, and surface area, but diminished biochar yield and polarity. Pyrolysis temperature positively affected biochar pH, surface area, and pore volume, while it had negative effects on biochar yield, oxygen and hydrogen contents, hydrogen/carbon and oxygen/carbon ratios, pore size, and function groups. However, residence time of pyrolysis had slight effects on biochar properties. The results are valuable for optimizing pyrolysis temperature and pretreatment measure of feedstocks, to tune S. alterniflora biochar properties for specific environmental usage.     

Stimulation of glucose utilization and lactate production in cultured human fibroblasts by thyroid hormone

Human dermal fibroblasts were obtained by harvesting outgrowing cells from the dermal tissue explants and cultured in Dulbecco's modified Eagle medium containing 10% fetal calf serum. After the cells reached confluency, culture was continued in the medium containing calf serum which was deprived of thyroid hormone by the treatment with activated charcoal. These fibroblasts were responsive to exogeneously added thyroid hormone (triiodothyronine) at physiological concentrations, resulting in enhanced utilization of glucose and production of lactate. This stimulation by thyroid hormone was dependent upon the length of exposure to the hormone and its concentration.The hormone did not show any effects on cellular DNA and protein content. The experimental system described above seems to be easy to reconstitute and should be useful for the elucidation of the mechanism of thyroid hormone action.     

Degradation of Machine Oil by Nocardioform Bacteria

Gas liquid chromatography (GLC) was used for the first time to screen for machine oil–degrading microorganisms. Oil degradation was evaluated from the microorganism respiratory activity during the utilization of oil as the sole carbon and energy source. The results are consistent with those obtained by the conventional weighing method. Substrate specificity of the active strains with respect to different machine oils was studied. Bacterial communities exhibited the highest activity, whereas a Rhodococcus erythropolisstrain was the most active among pure cultures. Various stages of bacterial interaction with oil drops were followed by means of fluorescent microscopy.     

Synergetic utilization of glucose and glycerol for efficient myo-inositol biosynthesis

myo-Inositol (MI) as a dietary supplement can provide various health benefits. One major challenge to its efficient biosynthesis is to achieve proper distribution of carbon flux between growth and production. Herein, this challenge was overcome by synergetic utilization of glucose and glycerol. Specifically, glycerol was catabolized to support cell growth while glucose was conserved as the building block for MI production. Growth and production were coupled via the phosphotransferase system, and both modules were optimized to achieve efficient production. First, the optimal enzyme combination was established for the production module. It was observed that enhancing the production module resulted in both increased MI production and better cell growth. In addition, glucose was shown to inhibit glycerol utilization via carbon catabolite repression and the inhibition was released by over-expressing glycerol kinase. Furthermore, the inducible promoter was replaced by strong constitutive promoters to avoid inducer use. With these efforts, the final strain produced MI with both high titer and yield. In fed-batch cultivation, 76 g/L of MI was produced, showing scale-up potential. This study provides a promising strategy to achieve rational distribution of carbon flux.     

Co-transfer of two plasmids determining bacteriocin production and sucrose utilization in Streptococcus faecium

Abstract Streptococcus faecium strain 25 produced a bacteriocin (enterococcin Sf25), metabolized sucrose and contained three plasmids of 2.4, 4.7 and 13.0 MDa. Plasmids Sfp2.4 and Sfp4.7 were cotransferred in a filter mating procedure to sucrose negative and bacteriocin negative S. faecium strain M16. Strain M16 harboured a nonselftransferable plasmid Sfp 19.1 MDa, which was responsible for erythromycin resistance. Transcipient cells of S. faecium M16 contained the 19.1-MDa plasmid and plasmids Sfp2.4 and Sfp4.7, produced the enterococcin Sf25 and gained the ability to degrade sucrose.     

Künstliche Luzerneheubereitungsverfahren in Ungarn

Abstract

An experiment was performed with Rumen Simulation Technique (Rusitec) in which the fermentation of mixed ration of hay (12.8 g/d) and wheat bran (3.2 g/d) was compared with the fermentation of the same diet supplemented with 2.5 and 10 mg monensin. The duration of the experiment was 12 days. During the first six days the fermentation conditions in Rusitec were stabilised. The end products of fermentation and indices of protein synthesis were determined. The energy efficiency of volatile fatty acids (VFA), proportion of fermented hexose energy on VFA energy and on energy of bacterial matter were increased in the presence of monensin. The proportion of fermented hexose energy in methane energy was decreased. Utilization of glucose and production of adenosintriphosphate were not affected. The balance of metabolic H₂ was reduced and this was manifested in decreasing production, utilization and recovery of metabolic H₂. Microbial efficiency expressed per mol ATP (g/mol) was increased by monensin from 7.8 to 12.6. The indices of protein synthesis — protein conversion ratio, degradability of protein and microbial protein synthesis efficiency were increased and non protein utilization ratio decreased in the presence of monensin.

Es wurde ein Versuch nach der Pansensimulationsmethode durchge-führt, in dem die Fermentierung einer gemischten Ration aus Heu (12,8 g/d) und Weizenkleie (3,2 g/d) mit der Fermentierung der gleichen Ration unter Zusatz von 2, 5 und 10 mg Monensin/d verglichen wurde. Die Dauer des Versuchs betrug 12 Tage, wovon die ersten sechs Tage der Stabilisierung der Fermentierungsbedingungen im Rusitec-System dienten.

Es wurden die Endprodukte der Fermentierung und die Kennziffern der Proteinsynthese bestimmt. Die Energieausbeute an Flüchtigen Fettsäuren (FFS), der Energieanteil fermentierter Hexose an der FFS-Energie und der Energie an Bakterienmasse erhöhten sich bei Zusatz von Monensin. Der Energieanteil fermentierter Hexose an der Methanenergie verringerte sich. Die Ausnutzung von Glukose und die Produktion von Adenosintriphosphat waren unbeeinflußt. Die Bilanz von metabolischem H₂ war verringert, was sich im Absinken der Production, der Nutzung und der Wiederauffindung von metabolischem H₂ zeigte. Die mikrobielle Wirksamkeit pro mol ATP (g/mol) erhöhte sich durch Monensin von 7,8 auf 12,6. Die Kennziffern der Proteinsynthese, die Proteinkonversionsrate, die Abbaubarkeit von Protein und die mikrobielle Proteinsynthesewirksamkeit erhöhten sich und die NPN-Nutzungsrate verringerte sich in Gegenwart von Monensin.