The potential use of anoxygenic phototrophic bacteria for treating latex rubber sheet wastewater

A total of 92 isolates of the purple non sulphur photosynthetic bacteria (PNSB) were isolated from 23 samples of wastewater obtained from rubber sheet manufacturing processes from various places of southern, Thailand. The isolate DK6 had the best potential for use in wastewater treatment as it can out-compete indigenous strains of PNSB when grown with them under conditions of microaerobic-light conditions. The isolate DK6 was identified as being most closely allied to Rhodopseudomonas blastica . The optimal pH and temperature for cell growth were between 6.5-7.5 and 30\ub0C, respectively. Optimum growth of DK6 was obtained after supplementing the wastewater from a latex rubber sheet processing plant with 0.50% (NH4)2SO4 and 1 mg/L nicotinic acid under conditions of microaerobic-light (3000 lux). Using these optimum conditions for growth, indigenous microorganisms reduced the initial chemical oxygen demand (COD) of the wastewater from 7,328 to 3371 mg/L a reduction of 54% and the biochemical oxygen demand (BOD) (initial BOD 4967 mg/L) by 70%. Using the same conditions and either a pure culture of DK6 or a mixed culture (DK6 plus indigenous microorganisms) a reduction of 90% of both COD and BOD was achieved. Chemical analysis of the cultures after treatment of the enriched wastewater shows that the protein content of the pure DK6 was 65.2% of the dry weight, and in mixed culture the protein content was 66.7%. Hence, single cell protein (SCP) may be a possible bi- product of the treatment process

Biodegradation of a blended starch/natural rubber foam biopolymer and rubber gloves by Streptomyces coelicolor CH13

Background: The growing problem of environmental pollution caused by synthetic plastics has led to the search for alternative materials such as biodegradable plastics. Of the biopolymers presently under development, starch/natural rubber is one promising alternative. Several species of bacteria and fungi are capable of degrading natural rubber and many can degrade starch. Results: Streptomyces coelicolor CH13 was isolated from soil according to its ability to produce translucent halos on a mineral salts medium, MSM, supplemented with natural rubber and to degrade starch. Scanning electron microscope studies showed that it colonized the surfaces of strips of a new starch/natural rubber biopolymer and rubber gloves and caused degradation by forming holes, and surface degradation. Starch was completely removed and polyisoprene chains were broken down to produce aldehyde and/or carbonyl groups. After 6 weeks of cultivation with strips of the polymers in MSM, S. coelicolor CH13 reduced the weight of the starch/NR biopolymer by 92% and that of the rubber gloves by 14.3%. Conclusions: This study indicated that this bacterium causes the biodegradation of the new biopolymer and natural rubber and confirms that this new biopolymer can be degraded in the environment and would be suitable as a \u2018green plastic\u2019 derived from natural sources

The potential use of anoxygenic phototrophic bacteria for treating latex rubber sheet wastewater

A total of 92 isolates of the purple non sulphur photosynthetic bacteria (PNSB) were isolated from 23 samples of wastewater obtained from rubber sheet manufacturing processes from various places of southern, Thailand. The isolate DK6 had the best potential for use in wastewater treatment as it can out-compete indigenous strains of PNSB when grown with them under conditions of microaerobic-light conditions. The isolate DK6 was identified as being most closely allied to Rhodopseudomonas blastica . The optimal pH and temperature for cell growth were between 6.5-7.5 and 30°C, respectively. Optimum growth of DK6 was obtained after supplementing the wastewater from a latex rubber sheet processing plant with 0.50% (NH4)2SO4 and 1 mg/L nicotinic acid under conditions of microaerobic-light (3000 lux). Using these optimum conditions for growth, indigenous microorganisms reduced the initial chemical oxygen demand (COD) of the wastewater from 7,328 to 3371 mg/L a reduction of 54% and the biochemical oxygen demand (BOD) (initial BOD 4967 mg/L) by 70%. Using the same conditions and either a pure culture of DK6 or a mixed culture (DK6 plus indigenous microorganisms) a reduction of 90% of both COD and BOD was achieved. Chemical analysis of the cultures after treatment of the enriched wastewater shows that the protein content of the pure DK6 was 65.2% of the dry weight, and in mixed culture the protein content was 66.7%. Hence, single cell protein (SCP) may be a possible bi- product of the treatment process

Carrier's Liability in International Carriage of Goods

The purpose of this thesis was to analyse and compare isseu of carrier's liability in international carriage of goods. Thesis is devided in seven parts, which offers outline of carrier's liability in particular modes of carriage. First part deals with term contract for the carriage according civil code, parts of this contract as well as another contracts which aim is carriage. Furthermore deals with term liability and put outline of distinction among strict liability and liability for fault. Last subchapter of first part describes term carriage. Second part describes legal framework of contract for the international carriage of goods and specifies distinction among choice of law and direct method. Remaining parts refer to carrier's liability according international treaties concerned with particular modes of carriage, i. e. international carriage of goods by road, by rail, by air, by sea and by inland waterways. Bigger attention is dedicated to third part which deals with carrier's liability in international carriage of goods by road. Emphasis to this part is given, because international carriage of goods by road is the most frequently one - especially from Czech point of view. International carriage of goods by road is for sixty years ruled by CMR Convention which was amended only twice. This mode..