Influence of production systems on phenolic characteristics and antioxidant capacity of highbush blueberry cultivars.

Blueberry is a crop grown worldwide due to the excellent quality and high polyphenol content of its fruit and tolerance to cold conditions. We investigated the influence of three production systems, namely an open field, heated greenhouse, and non-heated (plastic) greenhouse, on the phenolic characteristics (total phenolic, flavonoid, and anthocyanin content) and antioxidant capacities of "Spartan" (northern highbush), "Sharpblue" (southern highbush), and "O'Neal" (southern highbush) blueberry cultivars. The non-heated production system showed the highest phenolic characteristics and antioxidant capacity in "Spartan" and "O'Neal," while the open field production system showed the highest phenolic characteristics and antioxidant capacity in "Sharpblue." Derivatives of delphinidin and malvidin were two of the most abundant anthocyanins. The heated greenhouse production system resulted in larger amounts of delphinidin derivatives compared with the other production systems, while the blueberry grown in the non-heated greenhouse produced larger amount of malvidin derivatives. The anthocyanin profiles varied according to production system and blueberry cultivars. The principal component analysis loading plot of blueberries for individual anthocyanins explained over 95% of the total variance. In summary, the results of this study suggest that a strategic approach to blueberry production could elevate the phenolic content and antioxidant capacity of cultivated blueberry. PRACTICAL APPLICATION: The highbush blueberry, a rich source of bioactive polyphenols, is a popular fruit. The microclimate of the production system of highbush blueberries affects the concentrations of antioxidative phenolic compounds such as anthocyanins. Therefore, discovering and applying the appropriate method of production for each blueberry cultivar could facilitate production of high-quality blueberries rich in phenolic antioxidants.

Physiochemical properties, dietary fibers, and functional characterization of three yuzu cultivars at five harvesting times.

This research focused on physiochemical and nutritional properties and functional characterization of three cultivars of yuzu-Native, Tadanishiki yuzu, and Namhae1-during different seasons. According to the cultivar and harvest time, yuzu cultivars were analyzed for free sugar, dietary fiber, hesperidin, naringin, and flavonoid content as well as antioxidant and antihypertensive activity. During November, Namhae1 exhibited the highest fruit weight, °Brix/acidity ratio, and total dietary fiber content. Tadanishiki contained the highest fructose and sucrose levels, pectin and cellulose contents, and soluble dietary fiber. Tadanishiki also had the highest hesperidin content in October, while the naringin content and antioxidant activity were the greatest in November. Antihypertensive activity was also the strongest for Tadanishiki, which was picked in October and November. These results indicated that Tadanishiki in October or November was the best for consumption or favorable processing because of its excellent product quality and high levels of nutritional and functional compounds.

Phage PPPL-1, A New Biological Agent to Control Bacterial Canker Caused by Pseudomonas syringae pv. actinidiae in Kiwifruit.

Pseudomonas syringae pv. actinidiae (Psa) is a Gram-negative bacterium that causes bacterial canker disease in kiwifruit. Copper or antibiotics have been used in orchards to control this disease, but the recent emergence of antibiotic-resistant Psa has called for the development of a new control agent. We previously reported that the bacteriophage (or phage) PPPL-1 showed antibacterial activity for both biovar 2 and 3 of Psa. To investigate the possibility of PPPL-1 to control bacterial canker in kiwifruit, we further tested the efficacy of PPPL-1 and its phage cocktail with two other phages on suppressing disease development under greenhouse conditions using 6 weeks old kiwifruit plants. Our results showed that the disease control efficacy of PPPL-1 treatment was statistically similar to those of phage cocktail treatment or AgrimycinTM, which contains streptomycin and oxytetracycline antibiotics as active ingredients. Moreover, PPPL-1 could successfully kill streptomycin-resistant Psa isolates, of which the treatment of BuramycinTM carrying only streptomycin as an active ingredient had no effect in vitro. The phage PPPL-1 was further characterized, and stability assays showed that the phage was stable in the field soil and at low temperature of 0 ± 2 °C. In addition, the phage could be scaled up quickly up to 1010 pfu/mL at 12 h later from initial multiplicity of infection of 0.000005. Our results indicate that PPPL-1 phage is a useful candidate as a biocontrol agent and could be a tool to control the bacterial canker in kiwifruit by Psa infection in the field conditions.

Changes in phenolics, soluble solids, vitamin C, and antioxidant capacity of various cultivars of hardy kiwifruits during cold storage.

Hardy kiwifruits (Actinidia arguta) contain various bioactive compounds such as vitamin C and phenolics and can withstand cold temperatures. Changes in soluble solid, vitamin C, total phenolic, and total flavonoid content, and antioxidant capacity of three cultivars of hardy kiwifruits (A. arguta × A. deliciosa cv. Mansu, A. arguta cv. Haeyeon, and A. arguta cv. Chiak) were comparatively evaluated for 8 weeks of storage at 1 ± 0.5 °C. After the 8 weeks of storage, soluble solid content of three cultivars increased, whereas their vitamin C content decreased. Throughout this storage period, total phenolic and flavonoid content of cv. Mansu and cv. Haeyeon remained the same, while antioxidant capacity of these two cultivars also remained similar but with slightly more variations. Cv. Chiak, however, showed a decrease in total phenolic and flavonoid content and antioxidant capacity. These results suggest that cold storage of the hardy kiwifruits maintains levels of bioactive compounds.

Phenolic Profiles of Hardy Kiwifruits and Their Neuroprotective Effects on PC-12 and SH-SY5Y Cells against Oxidative Stress.

Hardy kiwifruits (Actinidia arguta Planch.) have high amounts of antioxidants, including ascorbic acid (vitamin C) and phenolics. The anti-cholinesterase activity and neuroprotective effects of three different cultivars of hardy kiwifruits, cv. Mansu (A. arguta × A. deliciosa), cv. Haeyeon (A. arguta), and cv. Chiak (A. arguta), on PC-12 and SH-SY5Y cells were evaluated. Extraction of phenolics and vitamin C was carried out using 80% (v/v) aqueous ethanol and metaphosphoric acid assisted with homogenization, respectively. Hardy kiwifruit of cv. Mansu showed higher total phenolic, total flavonoid, and vitamin C contents and antioxidant capacity compared to the other tw°Cultivars of hardy kiwifruits, cv. Haeyeon and cv. Chiak. Analysis of high-performance liquid chromatography results revealed the presence of procyanidin B2, (?)-epicatechin, neochlorogenic acid, cryptochlorogenic acid, rutin, hyperoside, isoquercitrin, and astragalin in hardy kiwifruits. The three cultivars of hardy kiwifruits had a wide range of vitamin C content of 55.2?130.0 mg/100 g fresh weight. All three cultivars of hardy kiwifruits had protective effects on neuronal PC-12 and SHSY5Y cells exposed to hydrogen peroxide by increasing cell viability and reducing intracellular oxidative stress. Furthermore, the hardy kiwifruits inhibited acetylcholinesterase and butyrylcholinesterase. Collectively, these results suggest that hardy kiwifruits rich in antioxidants like phenolics and vitamin C have good potential as functional materials in neuroprotective applications.

Kiwifruit of Actinidia eriantha cv. Bidan has in vitro antioxidative, anti-inflammatory and immunomodulatory effects on macrophages and splenocytes isolated from male BALB/c mice.

Kiwifruit is known to contain considerable amount of antioxidative phenolics. The objective of this study was to evaluate the antioxidative, anti-inflammatory and immunomodulatory effects of Actinidia eriantha cv. Bidan and A. deliciosa cv. Hayward kiwifruits. The antioxidant capacity of kiwifruit was measured with the DPPH, ABTS and ORAC assays, and was significantly (p < 0.05) higher in cv. Bidan than in cv. Hayward. The production of proinflammatory cytokines interleukin-6, interleukin-12 and tumor necrosis factor-α by peritoneal macrophages from male BALB/c mice was significantly (p < 0.05) lower following treatment of cv. Bidan extracts than after treatment with lipopolysaccharide alone. Cv. Bidan extracts significantly (p < 0.05) increased the proliferation of splenocytes stimulated with an anti-CD3 antibody and significantly (p < 0.05) reduced their interferon-γ secretion. Taken together, these findings suggest that cv. Bidan kiwifruit is rich in antioxidants and may be a source of anti-inflammatory and immunomodulatory agents.

Effects of freeze-drying on antioxidant and anticholinesterase activities in various cultivars of kiwifruit (Actinidia spp.).

Oxidative stress contributes to neurodegenerative disorders such as Alzheimer's disease. Phenolic antioxidants can efficiently reduce oxidative stress. In this study, we evaluated the effects of the freeze-drying process on phenolics, antioxidants, and cholinesterase inhibition in five cultivars of kiwifruits grown in Korea, Actinidia chinensis cv. Hort16A, cv. Happygold, and cv. Haegeum; A. deliciosa cv. Hayward; and A. eriantha cv. Bidan, by comparing them with their fresh counterparts. Among the five cultivars of both fresh and freeze-dried kiwifruits tested in this study, cv. Bidan had the highest levels of total phenolics, total flavonoids, and antioxidants, and cv. Hayward had the lowest. Freezedried kiwifruits inhibited acetylcholinesterase and butyrylcholinesterase that catalyze the breakdown of acetylcholine (neurotransmitter). On sensory evaluation, cv. Happygold had the highest overall preference scores among the freeze-dried kiwifruits. The results suggest that freeze-dried kiwifruit could serve as a good source of antioxidants and cholinesterase inhibitors.

Antioxidant and Anti-Inflammatory Effects of Various Cultivars of Kiwi Berry (Actinidia arguta) on Lipopolysaccharide-Stimulated RAW 264.7 Cells.

The present study evaluated the total phenolic and flavonoid contents as well as total antioxidant capacity (TAC) of three cultivars of Actinidia arguta Planch. kiwi berries; cv. Mansoo (Mansoo), cv. Chiak (Chiak), and cv. Haeyeon (Haeyeon). In addition, the anti-inflammatory effects of the three cultivars of kiwi berries were investigated using a lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophage cell line. Mansoo had the highest total phenolic content and TAC among the three cultivars, whereas Chiak had the highest total flavonoid content. The total antioxidant capacities of the kiwi berry extracts were more strongly correlated with total phenolic content than with total flavonoid content. The kiwi berry extracts suppressed the secretion of pro-inflammatory cytokines, including interleukin-6 and tumor necrosis factor-α, from LPS-stimulated RAW 264.7 cells. The release of nitrite, an indirect indicator of nitric oxide, was also ameliorated by pre-treatment with the kiwi berry extracts in a dose-dependent manner. Cellular-based measurements of antioxidant capacity exhibited that the kiwi berry extracts had cellular antioxidant capacities. Such cellular antioxidant effects are possibly attributed to their direct antioxidant capacity or to the inhibition of reactive oxygen species generation via anti-inflammatory effects. Our findings suggest that kiwi berries are potential antioxidant and anti-inflammatory agents.