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Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ascorbic acid or vitamin C is mostly found in natural products such as fruits and vegetables. Ultra performance liquid chromatography (UPLC) method has been developed to compare the ascorbic acid content in some fresh fruits (apple, orange) and vegetables (carrot, beet, cherry tomato) extracts with two different extraction solvents; i) 9% metaphosphoric acid, ii) 3% citric acid. The compound has been detected and quantified by the use of UPLC equipped with Photodiode Array (PDA) detector. The amount of ascorbic acid detected in fruits and vegetables extracts prepared with the two solvents mentioned was different. For the orange extracted using citric acid 3% recorded the highest concentration of ascorbic acid (38.2mg/100g FW) higher than with 9% metaphosphoric acid (33.3mg/100g FW), respectively the extractions of both varieties of apples, carrot, beet and cherry tomato with metaphosphoric extraction solvent recorded the highest values of ascorbic acid: 4.1mg/100g FW in case of ‘Golden’, 9.92mg/100g FW for carrot and 13.56mg/100g FW for beet. The results showed that ascorbic acid content was higher by extraction with 9% metaphosphoric acid as compared, by extraction with 3% citric acid. [ABSTRACT FROM AUTHOR]

Two wheat varieties grown in Upper and Delta Egypt were compared for their total phenolic content and antioxidant activities. Three solvent systems have been used to prepare the antioxidant extracts from whole wheat and its bran fraction. The three solvent systems included 50% acetone ( v / v ), 70% methanol ( v / v ) and 70% ethanol ( v / v ). Antioxidant activities were tested using DPPH radical scavenging activity and total flavonoid content. The results showed that the extraction solvents and wheat varieties significantly altered the total phenolics and antioxidant activity of whole wheat and bran, and 50% acetone is a recommended solvent for extracting phenolic compounds from the tested wheat and bran. Also data indicated that the bran fraction was rich in total phenolic content and high power for radical scavenging activity than whole wheat. These results showed that wheat bran could be considered as a potential source of antioxidant agent. Therefore, durum wheat variety (Beni-suef-3) showed high level of total phenol contact and antioxidant properties in bran fraction than common wheat variety (Gemiza-9). So, whole meal wheat products maximize health benefits and strongly recommended for use in food processing. [ABSTRACT FROM AUTHOR]

Abstract: Several species belonging to the genus Rhamnus (Rhamnaceae), comprising ones among which are found the most typical plants of the Italian flora, are known to contain biologically active anthraquinone secondary metabolites. Although several Rhamnus species were so far investigated, no information is available concerning the content and relative abundances of anthraquinones in R. saxatilis. In this study we used a simple, reliable, and accurate analytical method to determine the anthraquinones in bark of R. saxatilis. This allowed us also to trace a comparative study on the efficacy of different extraction solvents in ultrasonication time dependent assays. Separation and quantification of anthraquinones were accomplished using a C18 column with the mobile phase of H2O:methanol (40:60, v/v, 1% formic acid) at a flow rate of 0.7mL/min and a detection wavelength of 254nm, while the qualitative analyses were also achieved at a wavelength of 435nm.Finally, the described HPLC method, was used to obtain a specific chemical fingerprint for this species in comparison with other species from the same family. [Copyright &y& Elsevier]