Prediction of amino acids, caffeine, theaflavins and water extract in black tea using FT-NIR spectroscopy coupled chemometrics algorithms

2018 ◽  
Vol 10 (25) ◽  
pp. 3023-3031 ◽  
Author(s):  
Muhammad Zareef ◽  
Quansheng Chen ◽  
Qin Ouyang ◽  
Felix Y. H. Kutsanedzie ◽  
Md. Mehedi Hassan ◽  
...  

We have described the in situ prediction of amino acids, caffeine, theaflavins and water extract in black tea using FT-NIR coupled various variable selection algorithms.

Molecules ◽  
2021 ◽  
Vol 26 (21) ◽  
pp. 6739
Author(s):  
Fei Ye ◽  
Xiaoyan Qiao ◽  
Anhui Gui ◽  
Shengpeng Wang ◽  
Panpan Liu ◽  
...  

This study aimed to compare the effect of hot roller (HR) drying and hot air (HA) drying on the sensory evaluation, chemical quality, antioxidant activity, and metabolic profile of Yihong Congou black tea processed from E’cha NO1. The Yihong Congou black tea dried with HA obtained higher sensory scores and better chemical qualities such as the hue of tea brew color (a and b), content of theaflavins, thearubigins, water extract, free amino acids, tea polyphenol, and the ratio of polyphenol to amino acids as well as higher antioxidant capacities compared to that dried with HR. The HA drying tea increased the contents of volatile compounds that had positive correlation with sweet and flowery flavor, while the HR drying tea increased the contents of volatile compounds related to fruity flavor. Moreover, non-targeted metabolomics data indicated that the levels of most free amino acids significantly increased, while the levels of most soluble sugars reduced in the HA drying method compared to the HR drying method. The metabolic analysis was also consistent with the above results and revealed that D-ribose and gallic acid were the main characteristic metabolites of HA drying. Our results could provide a technical reference and theoretical guide to processing a high quality of Yihong Congou black tea.


2021 ◽  
pp. 096703352110079
Author(s):  
Agustan Alwi ◽  
Roger Meder ◽  
Yani Japarudin ◽  
Hazandy A Hamid ◽  
Ruzana Sanusi ◽  
...  

Eucalyptus pellita F. Muell. has become an important tree species in the forest plantations of SE Asia, and in Malaysian Borneo in particular, to replace thousands of hectares of Acacia mangium Willd. which has suffered significant loss caused by Ceratocystis manginecans infection in Sabah, Malaysia. Since its first introduction at a commercial scale in 2012, E. pellita has been planted in many areas in the region. The species replacement requires new silvicultural practices to induce the adaptability of E. pellita to grow in the region and this includes relevant research to optimise such regimes as planting distance, pruning, weeding practices and nutrition regimes. In this present study, the nutritional status of the foliage was investigated with the aim to develop near infrared spectroscopic calibrations that can be used to monitor and quantify nutrient status, particularly total foliar nitrogen (N) and phosphorus (P) in the field. Spectra acquired on fresh foliage in situ on the tree could be used to predict N and P with accuracy suitable for operational decision-making regards fertiliser application. If greater accuracy is required, spectra acquired on dry, milled foliage could be used to predict N and P within a relative error of 10% (R2c, r2CV, RMSEP, RPD = 0.77, 0.71, 0.02 g 100/g, 1.9 for foliar P and = 0.90, 0.88, 0.21 g 100/g, 3.0 for foliar N on dry, milled foliage). The ultimate application of this is in situ nutrient monitoring, particularly to aid longitudinal studies in fertiliser trial plots and forest operations, as the non-destructive nature of NIR spectroscopy would enable regular monitoring of individual leaves over time without the need to destructively sample them. This would aid the temporal and spatial analysis of field data.


2021 ◽  
Vol 60 (15) ◽  
pp. 5494-5503
Author(s):  
Valerio Loianno ◽  
Antonio Baldanza ◽  
Giuseppe Scherillo ◽  
Rezvan Jamaledin ◽  
Pellegrino Musto ◽  
...  

2016 ◽  
Vol 14 (2) ◽  
pp. 556-563 ◽  
Author(s):  
Veladi Panduranga ◽  
Girish Prabhu ◽  
Roopesh Kumar ◽  
Basavaprabhu Basavaprabhu ◽  
Vommina V. Sureshbabu

A simple and efficient method for the synthesis of N,N’-orthogonally protected imide tethered peptidomimetics is presented. The imide peptidomimetics were synthesized by coupling the in situ generated selenocarboxylate of Nα-protected amino acids with Nα-protected amino acid azides in good yields.


1972 ◽  
Vol 50 (1) ◽  
pp. 177-184 ◽  
Author(s):  
Johan A. Hellebust ◽  
Arne Haug

Amino acids, particularly alanine and aspartate, become more strongly labeled than mannitol in short-term 14C-photoassimilation experiments. The amino acids are the most likely sources of carbon for alginic acid synthesis and respiration in the dark, in contrast to mannitol, which appears to be relatively unavailable. Temperature is very important in determining the rate of loss of recent photoassimilate in L. digitata. The rate of photosynthesis, on a fresh weight basis, is much higher for blades than for stipes.The time course for incorporation of photoassimilated carbon into alginate differs for the stipe and blade both in light and dark periods. Very little 14C enters alginate in blades in the dark, while alginate in stipes acquires considerable amounts of activity during dark periods. Alginate in both blade and stipe acquires 14C predominantly in mannuronic acid residues of their alginate during short-term photoassimilation periods, while guluronic acid residues become relatively more rapidly labeled during dark periods.


2012 ◽  
Vol 124 (50) ◽  
pp. 12546-12546
Author(s):  
Erkin Kuru ◽  
H. Velocity Hughes ◽  
Pamela J. Brown ◽  
Edward Hall ◽  
Srinivas Tekkam ◽  
...  
Keyword(s):  

2011 ◽  
Vol 301-303 ◽  
pp. 1093-1097 ◽  
Author(s):  
Shi Rong Ai ◽  
Rui Mei Wu ◽  
Lin Yuan Yan ◽  
Yan Hong Wu

This study attempted the feasibility to determine the ratio of tea polyphenols to amino acids in green tea infusion using near infrared (NIR) spectroscopy combined with synergy interval PLS (siPLS) algorithms. First, SNV was used to preprocess the original spectra of tea infusion; then, siPLS was used to select the efficient spectra regions from the preprocessed spectra. Experimental results showed that the spectra regions [7 8 18] were selected, which were out of the strong absorption of H2O. The optimal PLS model was developed with the selected regions when 6 PCs components were contained. The RMSEP value was equal to 0.316 and the correlation coefficient (R) was equal to 0.8727 in prediction set. The results demonstrated that NIR can be successfully used to determinate the ration of tea polyphenols to amino acids in green tea infusion.


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