http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kumar Roushan,Devi Jyoti,Kumar Dinesh,Bhushan Shashi 한국식물생명공학회 2023 Plant biotechnology reports Vol.17 No.3
Indiscriminate collection of Arnebia benthamii roots from wild for extraction of red pigments by traders prompted to put this Himalayan plant species under critically endangered category. Concerning the development of sustainable phytoconstituents sources, the present study is aimed at understanding the factors crucial for the scalability of A. benthamii cell suspension cultures. Here, the effect of orbital shaking speed (60–80 rpm) and inoculum density (5–15%) on leaf-induced cell suspension cultures during sequential scale up in shake flask (0.25–5 L) was assessed. The suspension cultures were established on Murashige and Skoog medium supplemented with 10 μM 6-benzylaminopurine and 5 μM indole-3-butyric acid having a 20-days cultivation cycle. The data revealed a significantly (p ≤ 0.05) high biomass productivity (523.80 ± 5.95 g/L, fresh weight) in 0.25 L vessel with 10% inoculum at 70 rpm as compared to large (5.0 L) volume flask (310.80 ± 32.85 g/L). Interestingly, the optimum inoculum density was found to vary with the size of culture vessels. Furthermore, noticeable effects of sequential scaleup with shaking speed and inoculum density were also observed on hydrogen peroxide (stress indicator) production as well as enzymatic (catalase and phenylalanine ammonia-lyase activity) and non-enzymatic (phenolic compounds) antioxidant potential. A. benthamii cells cultivated with optimized conditions had a significant amount of red pigment, with 669.17 ± 26.71 mg dry weight/L yield of total shikonin derivatives. In conclusion, the results clearly demonstrated the likelihood of scalability using optimized process variables for the production of natural red pigments using A. benthamii cell suspension cultures.
Characteristic white light emission via down-conversion SrGdAlO4:Dy3+ nanophosphor
Anju Hooda,S.P. Khatkar,Avni Khatkar,Sangeeta Chahar,Sushma Devi,Jyoti Dalal,V.B. Taxak 한국물리학회 2019 Current Applied Physics Vol.19 No.4
An efficient and cost-effective technique, solution combustion synthesis was used to synthesize Dy3+ doped SrGdAlO4 nanophosphor utilizing urea as a suitable fuel. The tetragonal phase and nano-crystallinity of the synthesized phosphor belonging to I4/mmm space group was confirmed by powder X-ray diffraction (PXRD) and transmission electron microscope (TEM) technique respectively. Various crystal structure parameters and refined atomic positions of host matrix and SrGd0.95Dy0.05AlO4 nanophosphor were determined by Rietveld refinement. The two intense bands i.e. blue and yellow bands were observed in photoluminescence emission spectrum recorded at 352 nm excitation wavelength, associated to transitions 4F9/2→6H15/2 (484 nm) and 4F9/2→6H13/2 (575 nm) respectively. Photometric characterizations revealed the emission of white color by the synthesized nanophosphor proving its wide applications in WLEDs (white light emitting diodes). Band gap values calculated using diffuse reflectance spectra (DRS) were found to vary in the range of 5.50 eV–5.59 eV for host and doped lattice system. Keeping in mind, the concentration quenching phenomenon, SrGd0.95Dy0.05AlO4 was considered as optimized nanophosphor for WLEDs.