- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
The LH2 Complexes (B800-850 and B800-830) Are Assembled in the Cells of the Sulfur Bacterium Thiorhodospira sibirica Strain Kir-3 without Carotenoids
摘要： The results of assembling the light-harvesting complexes in the cells of the purple sulfur bacterium Thiorhodospira (T.) sibirica strain Kir-3 while suppressing the biosynthesis of carotenoids with diphenylamine (DPA) were studied. LH2 complexes (B800-850 and B800-830) with different carotenoid composition were isolated from the cells obtained. Maximum inhibition of carotenoid biosynthesis (~90% of the control) was reached at an inhibitor concentration of 53.25 μ M (9 mg/L). It was established that changes in the qualitative and quantitative composition of carotenoids do not affect the assembly of B800-830 and B800-850 complexes. It is assumed that, in the population of DPA-LH2 complexes from T. sibirica strain Kir-3, both the carotenoidless complexes and the complexes containing one or two carotenoid molecules can be assembled. These results support the hypothesis that carotenoids are not required for assembling B800-850 and B800-830 complexes.
关键词： Thiorhodospira sibirica,diphenylamine,B800-850,carotenoids,B800-830,LH2 complexes
更新于2025-09-11 14:15:04
-
The Unique Photophysical Properties of the Peridinin-Chlorophyll-a-Protein
摘要： Peridinin-Chlorophyll-a-Proteins (PCPs) are water-soluble light harvesting complexes from dinoflagellates. They have unique light-harvesting and energy transfer properties which have been studied in details in the last 15 years. This review aims to give an overview on all the main aspects of PCPs photophysics, with an emphasis on some aspects which have not been reviewed in details so far, such as vibrational spectroscopy studies, theoretical calculations, and magnetic resonance studies. A paragraph on the present development of PCPs towards technological applications is also included.
关键词： peridinin-chlorophyll-protein,peridinin,Carotenoids,photoprotection.,light-harvesting
更新于2025-09-11 14:15:04
-
Drying of Mangoes (Mangifera indica L.) applying Pulsed UV Light as Pretreatment
摘要： High-intensity pulsed UV light is a non-thermal treatment used in the sanitization of fruits. As a secondary effect to sanitization, the energy of the pulses is absorbed by the fruit and converted into internal energy, which results in partial evaporation of the water of the fruit. In this work, we have applied high-intensity pulsed UV light as a pretreatment for convective air-drying evaluating its advantages and disadvantages on the drying process and nutritional quality of the dried product. Mangoes were subjected to pulses of UV light and dried in a convective oven-drier. The pulsed UV light pretreatment reduced the water content in the samples but did not affect the kinetics or apparent water diffusivity of the subsequent drying process. The concentration of vitamin C and carotenoids in dried mangoes subjected to fluences between 3.6 and 10.8 J/cm2 in the pretreatment were between 10 and 40% higher than the untreated dried mango. The concentration of vitamins B1, B3 and B5 increased by 10 to 25% in dried mangoes subjected to fluences between 3.6 and 7.2 J/cm2, in comparison with the untreated dried mango. Vitamin B6 was highly affected by pulsed UV light decreasing by 40 to 50% in the pretreated mangoes.
关键词： drying,mango,UV light,vitamins,carotenoids,Mangifera indica L.
更新于2025-09-10 09:29:36
-
Quantification of Total Phenolic and Carotenoid Content in Blackberries (Rubus Fructicosus L.) Using Near Infrared Spectroscopy (NIRS) and Multivariate Analysis
摘要： A rapid method to quantify the total phenolic content (TPC) and total carotenoid content (TCC) in blackberries using near infrared spectroscopy (NIRS) was carried out aiming to provide reductions in analysis time and cost for the food industry. A total of 106 samples were analysed using the Folin-Ciocalteu method for TPC and a method based on Ultraviolet-Visible Spectrometer for TCC. The average contents found for TPC and TCC were 24.27 mg·g?1 dw and 8.30 μg·g?1 dw, respectively. Modified partial least squares (MPLS) regression was used for obtaining the calibration models of these compounds. The RPD (ratio of the standard deviation of the reference data to the standard error of prediction (SEP)) values from external validation for both TPC and TCC were between 1.5 < RPDp < 2.5 and RER values (ratio of the range in the reference data to SEP) were 5.92 for TPC and 8.63 for TCC. These values showed that both equations were suitable for screening purposes. MPLS loading plots showed a high contribution of sugars, chlorophyll, lipids and cellulose in the modelling of prediction equations.
关键词： bioanalytical applications,chemometrics,blackberries,near infrared,phenolics,carotenoids,Rubus fructicosus
更新于2025-09-04 15:30:14