Henan University of Technology

About: Henan University of Technology is a education organization based out in Zhengzhou, China. It is known for research contribution in the topics: Catalysis & Starch. The organization has 7648 authors who have published 6503 publications receiving 73067 citations. The organization is also known as: Hénán Gōngyè Dàxué.

Simultaneous determination of six plant growth regulators in fruits using high performance liquid chromatography based on solid-phase extraction and cleanup with a novel mixed-mode functionalized calixarene sorbent

Abstract: In this paper, a rapid and practical high performance liquid chromatography (HPLC) method, using home-made tetraazacalix[2]arene[2]triazine-modified silica gel (NCSi) as a solid-phase extraction (SPE) sorbent, was developed for the simultaneous determination of six plant growth regulators (PGRs) including thidiazuron (TDZ), naphthaleneacetic acid (NAA), p-chlorophenoxyacetic (PCPA), 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (6-BA) and forchlorfenuron (KT-30) in fruits. NCSi is a novel multi-interaction and mixed mode functionalized calixarene sorbent, which can enrich different classes of PGRs. Prior to HPLC separation, the key factors influencing SPE performance were investigated in the sample pretreatment step, including the dosage of the NCSi sorbent, and the flow rate, volume and composition of the eluant. HPLC analysis was carried out on a Waters XBridge C18 column (250 × 4.6 mm i.d., 5 μm) with a mobile phase of methanol/0.1% H3PO4 (55 : 45,v/v). With a detection wavelength of 220 nm, the good linearities of the six PGRs were obtained in the concentration range of 0.03 to 200 mg kg−1 (R2 ≥ 0.999). The lower detection limits (4.3–20.4 μg kg−1) and quantitation limits (12.9–64.0 μg kg−1) of the six PGRs were also obtained, which can meet the trace analysis requirements. In addition, overall recoveries through the extraction and purification steps ranged from 72.4 to 94.9%, and RSDs were less than 4.84%. The proposed method was successfully used to determine residual PGRs in real samples. It is practical and promising for the study of plant physiology by the determination of trace PGR content in the plant or fruits with a complex matrix.

Simultaneous esterification and transesterification of waste phoenix seed oil with a high free fatty acid content using a free lipase catalyst to prepare biodiesel

Abstract: Biodiesel is a typical renewable and green energy, that is usually produced by the transesterification of edible vegetable oils. However, the cost of edible vegetable oils as feedstock accounts for 60%–80% of the total cost of biodiesel production. To overcome these issues, in this work, a low-cost feedstock, waste phoenix seed oil (PSO) with a high free fatty acid (FFA) content (30.1 ± 0.6%), consisting of the main fatty acid, linoleic acid (30.2%), oleic acid (22.2%), and palmitic acid (17.4%), was developed as a new feedstock to prepare biodiesel. A novel one-step method including simultaneous esterification of FFAs and transesterification of the PSO to prepare biodiesel was developed. Free lipase was used as catalyst. The influences of the reaction parameters were explored and optimized by response surface methodology. The results showed that the free lipase Lipozyme TL100L from Thermomyces lanuginosus can simultaneously catalyze esterification and transesterification. Under the optimum conditions (enzyme load 9.7%, reaction time 6.9 h, reaction temperature 31 °C and substrate ratio (methanol/PSO) 4.3: 1 (mol/mol)), the maximum biodiesel yield (93.8 ± 0.5%) was achieved. The activation energy from biodiesel preparation using PSO with a high FFA content was 39.7 kJ/mol. Furthermore, the kinetic values for K'm and Vmax were 0.18 mol/L and 0.043 mol/(L·min), respectively. The reaction mechanism of the simultaneous esterification and transesterification was also proposed. These results indicate that PSO with a high FFA content can be used as a potential feedstock for biodiesel production.

Formation of Benzo(a)pyrene in Sesame Seeds During the Roasting Process for Production of Sesame Seed Oil

Abstract: The main aim of this research was to enhance the understanding of the formation mechanisms of benzo(a)pyrene (BaP) during roasting of sesame seeds (SS). BaP levels in hot- and cold-pressed sesame seed oil (SSO) were evaluated to correlate oil technology and BaP formation. Extracted principal components from SS were roasted either singly or in mixtures at 230 °C for 30 min. BaP was measured by HPLC with fluorescence detection. The results showed that BaP levels in hot-pressed SSO were significantly higher than those in cold-pressed SSO (p < 0.05), BaP formation mostly occurred during SS roasting and increased with roasting temperature (between 80 and 280 °C) and time (from 10 to 50 min). Furthermore, the BaP level in the roasted hulled SS (3.64 μg/kg) was higher than it was in roasted whole SS (1.63 μg/kg). The maximum BaP level observed (5.03 μg/kg) was detected in a roasted mixture of SS protein and SSO. The addition of sesame protein to protein-free SSO promoted the formation of BaP, which suggests that the pyrolysis products of protein and triacylglycerols are probably important precursors in BaP formation.