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Summary: Nine solvents of varying polarity (water, methanol, ethanol, isopropyl alcohol, acetone, n‐butyl alcohol, ethyl acetate, chloroform and petroleum ether) were used to determine the optimal extraction solvent that gives the highest yield of bioactive compounds from six Asparagus Officinalis L root (AR) cultivars from China and New Zealand. The contents of total phenolics (TPC), total flavonoids (TFC), total saponins (TSC) and caffeic acid (CA) were determined. Antioxidant assessments included ferric reducing/antioxidant power (FRAP), 2, 2′‐azinobis‐(3‐ diphenyl‐ethylbenzothiazoline‐6‐sulphonic acid) radical cation (ABTS) and β‐carotene bleaching activity assays. The results indicated that yellow AR from China had the highest content of TPC, TFC, TSC and CA compared to other AR cultivars. The most effective solvents for bioactive compound recoveries and antioxidant activities from A. officinalis L root extraction were ethanol and methanol. The content of CA in ethanol extracts of yellow AR achieved 92.0 mg g−1 DE. [ABSTRACT FROM AUTHOR]

Perilla frutescens var. acuta has traditionally been used to treat disease including, depression, inflammation and tumors. Especially, the presence of rosmarinic acid can induce beneficial and health promoting effects. According to, this work was conducted to comparison of various extraction conditions (extraction process, solvent and time) of total phenolic, floavonoid and rosmainic acid contents from the leaves of Perilla frutescens var. acuta. Also, rosmarinic acid was determined in leaves of Perilla frutescens var. acuta by high-performance liquid chromatography (HPLC) and the described method was ideally suited for rapid routine analysis. The highest yield of total phenolic, flavonoid and rosmarinic acid was shown 12.15 mg gallic acid equivalents g−1 dry weight (DW), 7.23 mg rutin equivalents g−1 DW and 3.76 mg g−1 DW, respectively. The best condition for extraction efficiency of total phenolic, flovonoid and rosmarinic were found to be: ethanol concentration of 70%, extraction time of 24 h and extraction process of refluxed extraction. [ABSTRACT FROM AUTHOR]

The objectives of this study were to screen the optimum conditions for antioxidant and antimicrobial activities of garlic as affected by pre-heating and different extraction solvents, and to evaluate the antioxidant and antimicrobial effects of these extracts in ground meat during refrigerated storage. Methanol extracted garlic had a greater total phenolic content, 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging activity and reducing power than water extracted one ( P < 0.05), whereas the latter had a greater yield and iron chelating ability than the former ( P < 0.05). Moreover, water extract from fresh garlic (WEFG) and methanol extract from heated garlic (MEHG) produced an inhibition zone against Escherichia coli O157:H7 and Listeria monocytogenes. The addition of garlic extracts (WEFG, MEHG and their combinations WEFMEHG)) to pork patties decreased the pH, hunter a values (redness), thiobarbituric acid substances values and the number of total plate count and Enterobacteriaceae ( P < 0.05), while the hunter b values (yellowness) increased ( P < 0.05). Results of this study indicated that the use of the garlic extracts was able to control lipid oxidation and microbial growth in pork patties. [ABSTRACT FROM AUTHOR]