• Journal of Microbiology and Biotechnology
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• 제29권2호
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• pp.256-267
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• 2019

The use of low-cost substrates represents one key issue to make single cell oil production sustainable. Among low-input crops, Arundo donax L. is a perennial herbaceous rhizomatous grass containing both C5 and C6 carbohydrates. The scope of the present work was to investigate and optimize the production of lipids by the oleaginous yeast Cutaneotrichosporon curvatus from undetoxified lignocellulosic hydrolysates of steam-pretreated A. donax. The growth of C. curvatus was first optimized in synthetic media, similar in terms of sugar concentration to hydrolysates, by applying the response surface methodology (RSM) analysis. Then the bioconversion of undetoxified hydrolysates was investigated. A fed-batch process for the fermentation of A. donax hydrolysates was finally implemented in a 2-L bioreactor. Under optimized conditions, the total lipid content was 64% of the dry cell weight and the lipid yield was 63% of the theoretical. The fatty acid profile of C. curvatus triglycerides contained 27% palmitic acid, 33% oleic acid and 32% linoleic acid. These results proved the potential of lipid production from A. donax, which is particularly important for their consideration as substitutes for vegetable oils in many applications such as biodiesel or bioplastics.

• 한국토양비료학회지
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• 제43권5호
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• pp.558-564
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• 2010

Cleaning up the landfill soil by phytoremediation in association with biomass production and utilization of biosolid as a soil amendment will be an attractive green technology. In order to examine this integrated green technology, in the current study of pot trial, heavy metal removal rate and biomass production were determined following cultivation of three different plant species in the landfill soil incorporated with biosolid at two different levels (25 ton $ha^{-1}$ and 50 ton $ha^{-1}$). Among the three plant species including Indian mustard (Brassica juncea), giant sunflower (Helianthus giganteus. L), and giant cane (Arundo donax. L), sunflower appeared to produce the largest biomass yield (19.2 ton $ha^{-1}$) and the produced amounts were magnificently increased with biosolid treatment compared to the control (no biosoild treatment). The increased production associated with biosolid treatment was common for other plant species and this was attributed to the biosolid originated nutrients as well as the improved soil physical properties due to the organic matter from biosolid. The elevated heavy metals in soil which was originated from the incorporated biosolid were Cu and Zn. Based on the phytoavailable amount of heavy metals from biosolid, the removed amount by plant shoots were 95% and 165% for Cu and Zn, respectively, when sunflower was grown. This indicated that mitigation of heavy metal accumulation in soils achieved by the removal of metal through sunflower cultivation enables the successive treatment of biosolid to soils. Moreover, sunflower showed heavy metal stabilization ability in the rhizosphere resulting in alleviation of metal release to ground water.

• KSBB Journal
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• 제30권3호
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• pp.97-102
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• 2015

This study aimed to evaluate the potential plantgrowth promoting effects of potassium polyacrylate, a superabsorbent polymer, and Bacillus sp. SH1RP8, a family of plant-growth-promoting bacteria. Potassium polyacrylate was selected as the polymer for use due to its high molecular weight and its ability to retain and continuously supply moisture. Plant-growth-promoting rhizobacteria (PGPR) were isolated from the soil and applied to plants growing in dry environments, such as saline conditions. The moisture absorption and retention abilities of potassium polyacrylate were evaluated at a high temperature ($50^{\circ}C$) and in a dry condition, during which time the polymer showed a water retention potential of 19606.07% after 29 days. To overcome the reaming problem in the soil environment, natural polymers (such as cellulose) were mixed with the potassium acrylate. The shoot growths of Peucedanum japonicum Thunb and Arundo donax were significantly enhanced when treated with the mixture of the isolated rhizosphere bacterium SH1RP8 and potassium polyacrylate (63.5 and 124.3%, respectively).

• 대한환경공학회지
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• 제35권10호
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• pp.687-693
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• 2013

다양한 난개발과 해안도로, 방파제 등의 인공 구조물 설치로 인한 해안 침식과 해안선 파괴 등으로 해안사구가 크게 훼손되고 있다. 이에 본 연구에서는 해안사구에서 서식하고 있는 토착식물의 근권으로부터 식물 성장 촉진 능력이 있으면서 동시에 염분에 강한 내성을 가지는 근권세균의 library를 구축하였고, 이들 균주를 대상으로 식물 성장 촉진 능력을 평가하였다. 또한, 내염성 식물을 대상으로 사구 토양에서의 성장률에 근권세균이 미치는 영향을 평가한 후, 훼손된 사구의 복원에 가장 유용한 미생물을 선별하고 분리된 근권세균이 식물 성장에 미치는 영향을 평가하였다. 실험은 선정된 균주와 갯기름나물과 줄무늬갈대를 해안사구에 식재한 후 성장에 미치는 영향을 평가하였다. 그 결과, MH1RS1는 (IAA) production, siderophores, 1-aminocyclopropane-1-carboxylate deaminase (ACC deaminase) 그리고 염분내성을 가지고 있다. 갯기름나물의 경우는 줄기의 길이와 뿌리의 무게는 크게 향상되었다. 특히, 줄기의 생체와 뿌리 무게는 control과 비교했을 때 25% 성장이 향상되었다. 줄무늬 갈대는 Bacillus aerius MH1RS1 에 의해 초장은 18%와 뿌리의 생체 중은 20%로 크게 향상 되었다.