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Browsing by Author "Niyaz Ahmad"

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    Evaluation of solvent and temperature effect on green accelerated solvent extraction (ASE) and UHPLC quantification of phenolics in fresh olive fruit (Olea europaea),
    (2021) Rizwan Ahmad; Niyaz Ahmad; Ahmed Aljamea; Saad Abuthayn; Mohammed Aqeel
    A green ASE (accelerated solvent extraction) with a shorter UHPLC (ultra-high performance liquid chromatography) method was developed for simultaneous determination of phenolics. High extract yield (130آ mg/g) was observed for water at 100آ آ°C in a short time of 19.5آ min using 33.5آ mL solvent whereas, UHPLC showed more phenolics of GA (gallic acid), QT (quercetin), LT (luteolin) in ACE (acetone) and RT (rutin) in EtOH (ethanol) solvent at 60آ آ°C. The binary solvent system of ACE: EtOH (1:1) at 60آ آ°C was optimized as extraction set. UHPLC runtime was 3آ min with retention times of (min); 0.63 (GA), 0.97 (RT), 2.00 (QT) and 2.41 (LT). Average for phenolics (ppm) was, QT (10.91)آ >آ GA (7.33)آ >آ LT (4.10)آ >آ RT (3.90) whereas, Spanish whole green olive (SP2) showed more phenolics (20.72). Individual phenolic was, GA (47.06)آ >آ RT (26.21)آ >آ QT (19.34)آ >آ LT (6.18). Multivariate, K-mean and PCA (principal component analysis) for solvent*extract yield showed significant correlation and temperature showed no significant correlation for phenolics.
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    Green accelerated solvent extraction (ASE) with solvent and temperature effect and green UHPLC-DAD analysis of phenolics in pepper fruit (Capsicum annum L.),
    (2021) Rizwan Ahmad; Niyaz Ahmad; Sadeq Alkhars; Ali Alkhars; Mohammed Alyousif; Ali Bukhamseen; Saad Abuthayn; Mohammed Aqeel; Ahmed Aljamea
    The study presents for the first time, a green and efficient accelerated solvent extraction (ASE) method for phenolic compounds (GA gallic acid, QT quercetin, RT rutin, LT luteolin) with simultaneous determination using a green and effective UHPLC-DAD method. The effect of solvents (ACE acetone, EtOH ethanol, and H2O water) and temperatures (60, 80, 100 °C) Vs extract yield and phenolic recovery was investigated. The scale-up for ASE-UHPLC method was accomplished in 27 food-grade samples of Capsicum annum/pepper fruit (PF). ASE-MD (method development) showed a high extract yield (198.23 mg/g) in water (33 mL) at 100 °C within a time frame of 19.5 min. UHPLC-DAD revealed more yield for GA in ACE whereas, for RT, QT, LT in EtOH at 60 °C. Binary solvent system (ACE: EtOH; 1:1) and 60 °C was optimized the extraction set. The UHPLC-MDMV showed a run time of 5 min with individual retention times of 0.667 (GA), 1.05 (RT), 3.24 (QT), and 3.78 (LT) in the linearity range (1–100 ppm). The average for phenolics (ppm) in 27 PF-food samples was; GA (19.46) > QT (10.19) > LT (4.06) > RT (2.41). SP4 (Spanish green bell pepper) sample showed more amount of total phenolics (32.52 ppm, 25.36 %) whereas, the order for individual phenolic amount (ppm) was; GA (53.39) > QT (13.58) > RT (10.04) > LT (4.62). Multivariate analysis resulted a significant correlation for solvent*temperature with extract yield but with a lack of correlation for phenolics amount. K-mean correlation was positive for solvent Vs phenolic yield (P < 0.05) whereas, extract yield and temperature were less significant for phenolics content. Solvent established a high significant role for extraction and phenolic recovery whereas, temperature was more significant for extract yield rather than phenolic amount.