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关键词： Blueberry   PPOs   Purification   Biochemical properties   Binding mechanism   CHLOROGENIC ACID   PURIFICATION   TYROSINASE   PROTEIN   MECHANISM   DAMAGE  

摘要： Purification of blueberry polyphenol oxidase (PPO) has not been substantially progressed for a long time, which leads to little further study. We purified three PPOs from blueberries for the first time by modified Native-Page. The PPO-2 consists of two subunits (68 and 36 kDa), whereas PPO-3 and PPO-4 contain only one subunit (36 kDa). The optimum pH and temperature of PPO-2, PPO-3, and PPO-4 were 5.8-6.2 and 40 degrees C-45 degrees C with catechol as a substrate. The optimal substrates for them were all catechol (K-m = 14.91, 7.19, and 11.20, respectively). High-pressure processing (HPP) had a limited inhibitory effect on the three PPOs. The activities of PPO-2, PPO-3, and PPO-4 were significantly reduced with increased SDS concentration. The binding of substrate to catalytic cavity is related to the residues His76, His209, His213, Gly228, and Phe230. The carbonyl group of residue Gly228 is one of the key sites for screening substrates.

关键词： Fish health indicators   Salmonids   Farmed fish   Fish blood samples   Reference intervals   RAINBOW-TROUT   ACUTE STRESS   CHEMISTRY   PARAMETERS   SURVIVAL   INDEXES   GROWTH   INDICATORS   CORTISOL   WALBAUM  

摘要： Blood biochemistry and haematological parameters in fish are affected by environmental changes, nutritional status, stress and health. As such, they are useful indicators of fish health and welfare. However, the correct interpretation of these parameters depends on the availability of species-specific reference values. This study provides baseline data and reference ranges for 34 blood biochemistry and haematological indicators for presumed healthy Chinook salmon, Oncorhynchus tshawytscha, including a comparison of the normal ranges of individuals sampled from freshwater and seawater farms in New Zealand. We found significant differences between the two environments for some parameters, including haematocrit, haemoglobin, sodium, chloride, potassium, globulin, cholesterol, haptoglobin and enzymes including alkaline phosphatase, aspartate aminotransferase and creatinine phosphokinase. We also found that some parameters were significantly correlated with fish size, and in some cases, this relationship was also affected by the environment where the fish was farmed. Our results are an important step forward in developing blood biochemistry and haematology tools to assess the health status of farmed Chinook salmon in New Zealand.

关键词： Forsythiaside A   Hepatoprotection   Acetaminophen   Liver injury   Network pharmacology   MATRIX METALLOPROTEINASES   INDUCED HEPATOTOXICITY   N-ACETYLCYSTEINE   WEB SERVER   SUSPENSA   PROTECTS   MECHANISM   APOPTOSIS   EXTRACT   CANCER  

摘要： Ethnopharmacological relevance: Forsythiae Fructus, the dried fruit of Forsythia suspensa (Thunb.) Vahl, is a commonly used traditional Chinese medicine and possesses various pharmacological activities, including anti inflammation, anti-oxidant and liver protection. Aim of the study: Although acetaminophen (APAP) has been frequently used for its antipyretic and analgesic effects, it leads to liver injury at an overdose or long-term medication. Forsythiaside A (FA), the principal active component of Forsythiae Fructus, exerts prominent antioxidant, anti-inflammatory and hepatoprotective effects. However, the protective property and underlying mechanism of FA against APAP challenge have not yet been elucidated. Therefore, we aimed to explore the hepatoprotective effect and action mechanism of FA against APAP-induced liver injury in zebrafish. Materials and methods: In this study, liver-specific transgenic zebrafish larvae (lfabp: EGFP) were used to investigate the protective effect of FA against overdose APAP exposure. The liver phenotype, morphological and biochemical assessments were carried out to evaluate the hepatoprotective effect of FA. Network pharmacology and molecular docking study were conducted to analyze the potential targets of FA in the treatment of APAPinduced liver injury. Finally, the mechanism of action was verified by reverse transcription quantitative realtime polymerase chain reaction (RT-qPCR). Results: The liver phenotype, morphological and biochemical assessments indicated that FA could mitigate APAPtriggered liver injury. Network pharmacology and molecular docking analysis indicated that the protective effect of FA might be related to the regulation of targets tumor necrosis factor (TNF), matrix metallopeptidase 9 (MMP9), matrix metallopeptidase 2 (MMP2), and phosphatidylinositol 3-kinase (PI3K). PCR results confirmed that FA could reverse the progressive alterations of genes involving in extracellular matrix remolding and PI3K/ AKT-mediated

关键词： Citrus phenotypical traits   Real-time retrieval   Leaf and canopy scale   Seasonal dynamics   Physiological informatics   Fruit orchards   WATER-STRESS DETECTION   LEAF-AREA INDEX   NITROGEN-CONTENT   CHLOROPHYLL CONTENT   CANOPY REFLECTANCE   MULTISPECTRAL IMAGERY   INFRARED SPECTROSCOPY   STOMATAL CONDUCTANCE   DEFICIT IRRIGATION   HYPERSPECTRAL DATA  

摘要： Remote sensing provides accurate and cost-effective solution to quantify the biophysical and biochemical traits of citrus fruit orchards. Timely information on these traits can be used to design real-time computerized applications for site-specific orchard management, yield estimation, and scheduling precise and proper application of inputs thus growing net returns and optimizing resource utilization. Retrieval of these traits has been playing an important role during the last 30 years with steady improvement in remote sensing platforms and sensors and the techniques and methods forthwith. However, with dense canopy, variable illumination conditions and saturation effects caused by seasonal dynamics of leaf and canopy pigments combined with high year-round leaf density pose challenges for the accurate and precise inference of biophysical and biochemical traits in citrus fruit orchards. Concerning these challenges in the pursuit of earth observation, the present paper aims to provide a comprehensive and in-depth review of the remotely sensed technologies and applications for real-time and state-of-the-science retrieval of biophysical and biochemical traits of citrus fruit orchards. Establishing a database of citrus traits at leaf, canopy and orchard level is very important for future smart agriculture to help farmers for site-specific orchard management, plan farm management practices, selection of best cultivars, scheduling precise and proper application of inputs in citrus production paradigm; thus growing net returns and optimize resource utilization. Technical methods for different levels of remote sensing acquisition have also been elaborated highlighting the current situation of citrus traits acquired by remote sensing.

关键词： Cut flower   Vase life   Calotropis   Antibacterial   Enzyme activity   POSTHARVEST PERFORMANCE   ANTIBACTERIAL ACTIVITY   CALOTROPIS-PROCERA   WATER RELATIONS   MOVIE STAR   ROSE   L.   BLOCKAGE   SENESCENCE   LONGEVITY  

摘要： Gladiolus is among the most versatile cut flowers and available in an array of colors. However, it has a relatively short vase life, associated with increased postharvest losses and decreased quality. Commercially, synthetic chemicals are applied to enhance its postharvest vase life, but in general they are not environmentally friendly. The current research aimed to evaluate whether natural plant extracts can serve as effective preservatives to extend the postharvest vase life of gladiolus spikes. There is no record in the literature of the use of leaf extract of Calotropis procera as a vase-life extender for cut flowers, though its leaf extract has been shown to have antimicrobial, antioxidant and insecticidal activity. In contrast, leaf extract of Moringa sp. and Mentha sp. are commonly known to extend the vase life. The leaf extracts of Moringa olifera, Mentha piperita and Calotropis procera at 2 and 4 % were used in holding solutions to compare their effects on vase life, physiological and metabolic activities of gladiolus cut spikes. In current results, Calotropis procera leaf extract (CPLE) at 2 % exhibited maximum vase life up to 14.50 days, open florets (64 %) and RFW (40 %) in comparison to Moringa olifera leaf extract (MOLE) and Mentha piperita leaf extract (MPLE). Similarly, maximum RWC (41 %), MSI (30 %), and CAT (66 %), POX (74 %), SOD (57 %) and reduced bacterial count (64 %) was also recorded in 2 % CPLE than MOLE and MPLE over untreated spikes. The cut spikes preserved in 2 % MOLE described maximum Chl a, (71 %), Chl b (64 %) and Car (49 %) contents than CPLE. Hence, CPLE at 2 % appears to be an effective natural preservative to prolong the vase life of gladiolus cut spikes.

关键词： Solanum lycopersicum var. cerasiforme   Functional food   Antioxidant activity   Sensory analysis   Postharvest quality   ANTIOXIDANT ACTIVITY   ASCORBIC-ACID   CHERRY TOMATO   QUALITY   FRUITS   MASTICATION   VEGETABLES   CAPACITY   TEXTURE   HARVEST  

摘要： The choice of promising parents represents a crucial step in developing improved cultivars in breeding programs for mini-tomatoes-highly demanded miniature vegetables. The association of non-sensory and sensory features of fruit greatly enhances the generation of cultivars that meet the expectations of the productive and commercial chain of tomatoes, focusing on diverse market niches. Thus, in this study, five genotypes of mini-tomatoes were characterized based on physical, biochemical, and sensory attributes. The genetic material encompasses four cultivars (BRS Iracema, BRS Zamir, Irai, and Sweet Heaven) and one landrace (UEL 238). The fruit were characterized by their dimension, color, firmness, soluble solids content, acidity, vitamin C, carotenoids, phenolic compounds, flavonoids, and antioxidant activity. In the sensorial test, 109 participants, including 27 chefs, evaluated the shape, size, color, aroma, flavor, texture, and overall liking of the fruit. The cultivar Sweet Heaven, with an oblong red fruit, brought together the main desirable physical traits, such as greater mass, pericarp thickness, firmness, and soluble solids content; while BRS Zamir presented superior values for biochemical characteristics, such as total phenolic compounds, total flavonoids, and antioxidant activity. Despite the lesser appreciation of the landrace UEL 238, all genotypes were accepted by consumers, especially BRS Iracema (round red fruit), followed by Irai (oblong yellow fruit). The characterized mini-tomatoes may be explored in breeding programs as promising parents to combine desirable sensory attributes with the highest nutraceutical quality, resulting in superior cultivars that have been increasingly demanded on the market.

关键词： Abiotic stress   Antioxidant system   Hydroponics   Strawberry   Water quality   TRANSCRIPTIONAL REGULATION   DROUGHT STRESS   PLANTS   BALANCE   H2S   PHOTOSYNTHESIS   TOLERANCE   AUTOPHAGY   SALINITY   CADMIUM  

摘要： Plant stress caused by alkalinity in irrigation water can significantly limit the growth and development of plants. Emerging evidence suggests that hydrogen sulfide (H2S), as a versatile signal molecule, can ameliorate stress-induced adverse effects. The objective of this study was to determine the effects of sodium hydrosulfide (NaHS) application on growth, fruit yield and biochemical responses of strawberry plants exposed to alkalinity stress under greenhouse conditions. Strawberry plants were grown hydroponically under three levels (0, 15 and 30 mM) of alkalinity stress (induced using sodium bicarbonate and sodium carbonate) along with three levels of foliar application (0, 0.2 and 0.5 mM) of the H2S donor, NaHS. The results showed that compared to the control conditions, alkalinity stress reduced plant biomass, fruit yield, maximum quantum efficiency of photosystem II (Fv/Fm) and chlorophyll SPAD value. Oxidative stress was induced, which was measured, as accumulation of reactive oxygen species (ROS). On the other hand, when alkalinity stress was mitigated with the application of NaHS, the recovery of photosynthetic activity, a decrease in ROS and an improvement in antioxidative defense system were observed. Overall, NaHS treatments had the best results on lower level (15 mM) of alkalinity stress compared to the 30 mM alkalinity stress. These findings indicate possible role for H2S for improving strawberry plant growth and yield under non-stress conditions and moderate alkalinity stress.