Expression Analyses in the Rachis Hint towards Major Cell Wall Modifications in Grape Clusters Showing Berry Shrivel Symptoms.

Berry shrivel (BS) is one of the prominent and still unresolved ripening physiological disorders in grapevine. The causes of BS are unclear, and previous studies focused on the berry metabolism or histological studies, including cell viability staining in the rachis and berries of BS clusters. Herein, we studied the transcriptional modulation induced by BS in the rachis of pre-symptomatic and symptomatic clusters with a custom-made microarray qPCR in relation to a previous RNASeq study of BS berries. Gene set analysis of transcript expression in symptomatic rachis tissue determined suppression of cell wall biosynthesis, which could also be confirmed already in pre-symptomatic BS rachis by CESA8 qPCR analyses, while in BS berries, a high number of SWITCH genes were suppressed at veraison. Additionally, genes associated with the cell wall were differently affected by BS in berries. A high percentage of hydrolytic enzymes were induced in BS grapes in rachis and berries, while other groups such as, e.g., xyloglucan endotransglucosylase/hydrolase, were suppressed in BS rachis. In conclusion, we propose that modulated cell wall biosynthesis and cell wall assembly in pre-symptomatic BS rachis have potential consequences for cell wall strength and lead to a forced degradation of cell walls in symptomatic grape clusters. The similarity to sugar starvation transcriptional profiles provides a link to BS berries, which are low in sugar accumulation. However, further studies remain necessary to investigate the temporal and spatial coordination in both tissues.

Application of ultrasonic incorporated with calcium gluconate maintains physicochemical quality of pink guavas during short-term storage at room temperature.

The effectiveness of simultaneous calcium gluconate (0.5% w/v) (Ca-G) and ultrasonication (Ca-G + US) on physicochemical quality of pink guavas under room temperature (27 ± 1 °C) was monitored. The fruits were sonicated for 2, 4, 6 and 8 min and the untreated fruits were defined as control. Peel discoloration and black spot disease were evidently controlled by Ca-G + US for 4 min. The treatment delayed the loss of acidity and total chlorophylls content and the increase in total carotenoids content. The fruit softening and cell membrane permeability and peroxidation were retarded by Ca-G + US for 4 min. Ca-G + US for 4 min enhanced ascorbic acid content and maintained total phenols content and antioxidant activity. In conclusion, the application of Ca-G + US for 4 min is feasible approach maintaining physicochemical quality such as peel color, texture and nutritional value of pink guavas during the short-term storage.

Impact of steaming pretreatment process on characteristics and antioxidant activities of black garlic (Allium sativum L.).

Impact of steaming pretreatment processes on physical properties, bioactive compounds and antioxidant activities, of black garlics (Allium sativum L.) was studied. Steaming pretreatment at different times (0, 4 and 6 min) was conducted before incubating in 60 °C-incubator at different incubation times (0, 9 and 18 days). Different steaming pretreatment processes affected the color and hardness of black garlic differently, while total polyphenol content (TPC) and total flavonoid content (TFC) were also determined by the steaming pretreatment time used. TPC and TFC increased with increasing of incubating time, where the highest those bioactive compounds was observed from 18-day incubation, especially with 4 min of steaming pretreatment (p ≤ 0.05). Increase of those bioactive compounds was in accordance with increasing of DPPH radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP) of black garlic during incubation. In addition, black garlic obtained from 18-day incubation with steaming pretreated for 4 min revealed the optimum condition providing the black garlic with high in both DPPH and FRAP, compared with others (p ≤ 0.05). Therefore, steaming pretreatment could effectively improve the efficiency of black garlic production process by increase the generation rate of bioactive compounds as well as induce antioxidant properties of black garlic with shorten process time.

Ultraviolet-C irradiation maintaining texture and total sugars content of ready to cook baby corn during commercial storage.

The aim of this study was to investigate the effects of ultraviolet-C (UV-C) irradiation on the changes in total sugars concentration and texture of ready to cook baby corn during cold storage. The baby corns were irradiated with UV-C at the dose of 0 (control), 2.2, 4.4 and 6.6 kJ m-2 and then stored at 5 ± 1 °C for 7 days. The results showed that the losses of total sugars were delayed by UV-C irradiation treatments. All the UV-C treatments significantly maintained the firmness of the treated baby corn samples and prevented the increase in electrolyte leakage, especially at 4.4 kJ m-2. Compared to control sample, the 4.4 kJ m-2 UV-C irradiated baby corn retarded the depolymerisation of pectin substances by suppressing the polygalacturonase and pectin methyl esterase activities. Therefore, the dose of 4.4 kJ m-2 could be a feasible alternative UV-C treatment maintaining texture and the total sugar concentration of ready to cook baby corn during commercial storage.

Browning inhibition on fresh-cut apple by the immersion of liquid endosperm from mature coconuts.

The application of natural antibrowning agents for fresh-cut products has been recently considered. This study manifested the efficiency of coconut liquid endosperm, coconut water (CW), from mature tall (cooking) coconut (C-CW) and yellow dwarf coconut (Y-CW) on browning inhibition of 'Gala' apple wedges during storage at 4 ± 1 °C for 9 days. The apple wedges were immersed in water (control), C-CW or Y-CW for 1 min. The visual appearance, superficial colour attributes, browning pigment concentration, total phenols concentration, polyphenoloxidase (PPO) activity and reducing antioxidant capacity of apple wedges were monitored. Moreover, antioxidant activity of both C-CW and Y-CW was also observed. Antioxidant activity of Y-CW was higher than that of C-CW. Both of the CW immersions maintained visual appearance, whiteness and lightness values as well as delayed the increased yellowness and brownness values of hypanthium (flesh) and mesocarp (core) of apple wedges. The browning pigment concentration and PPO activity were obviously lowered by both CW immersions. Total phenols concentration and antioxidant activity of C-CW and Y-CW immersed apple wedges were higher than those of control samples. In conclusion, both of the mature coconut liquid endosperms are feasible natural agent inhibiting browning incidence of fresh-cut fruits during storage.

Phytohormone profiles are strongly altered during induction and symptom development of the physiological ripening disorder berry shrivel in grapevine.

The process of grape berry ripening follows three phases with distinct metabolic processes and complex regulations via phytohormones. The physiological ripening disorder berry shrivel (BS) is characterized by reduced sugar accumulation, low anthocyanin contents, and high acidity in affected berries. The processes leading to BS induction are unknown, but recent transcriptional data on reduced expression of switch genes hint towards a disturbed ripening onset. Herein we investigated the phytohormone composition throughout grape berry ripening in healthy and BS berries in Vitis vinifera L. cultivar Blauer Zweigelt. Thereby we hypothesize that phytohormones are key players for BS induction and suppress the expression of switch genes at veraison. The presented metabolomics and RNAseq data describe two distinct phytohormone profiles in BS berries, differing between pre- and post-veraison with a clear ethylene precursor (aminocyclopropane-1-carboxylic acid, ACC) peak before veraison. Exogenous application of ACC led to BS symptoms, while ethephone application led to berry abscission. During post-veraison, we observed high ABA-glucose ester (ABA-GE) and low indole-3-acetate aspartate (IAA-Asp) and isopentenyladenine (iP) contents in BS berries and the transcriptional induction of several phytohormone pathways. The presented descriptive data provide valuable knowledge to further decipher the role of phytohormones in BS induction and BS symptom development.

Efficiency of salicylic acid or methyl jasmonate immersions on internal browning alleviation and physicochemical quality of Queen pineapple cv. "Sawi" fruit during cold storage.

The pineapples were dipped in salicylic acid (SA) (2.5 or 5.0 mM) or methyl jasmonate (MeJA) (0.01 or 0.1 mM) for 1, 2, or 3 hr and then held at 13 ± 1°C for 10 days. The parameters were determined after left the fruits at 25°C for 2 days. It was found that, in the tissue adjacent to the core, 5.0 mM SA for 2 hr and 0.01 mM MeJA for 3 hr alleviated chilling injury (CI) and maintained color than other treatments. The MeJA immersions lowered CI score, electrolyte leakage, and malondialdehyde content greater than other treatments. SA and MeJA immersions retarded polyphenol oxidase activity, total phenols, and induced antioxidant activity during storage. In the pulp tissue, SA treatment increased ascorbic acid and total sugar contents, and MeJA immersions enhanced bioactive compound and antioxidant enzyme activities than SA immersion. Therefore, MeJA immersions could alleviate CI and enhance antioxidant better than other treatments of pineapples during cold storage. PRACTICAL APPLICATIONS: Postharvest immersion at the optimum concentration of SA or MeJA can be applied for commercial scale in order to alleviate chilling of "Sawi" pineapple fruit during storage. MeJA treatment enhances antioxidant activity and reduces internal browning better than SA treatment in pineapple.

Efficiency of combinative salicylic acid and chitosan preharvest-treatment on antioxidant and phytochemicals of ready to eat daikon sprouts during storage.

Effects of salicylic acid (SA), chitosan and combinative SA and chitosan (SA + Chitosan) preharvest-treatments on bioactive compounds improvement of daikon sprouts during cold storage (5 ±â€¯1 °C) were investigated. In preliminary experiment, 2.0 mM SA and 0.1% chitosan treatments were best concentration in improving antioxidant activity and bioactive compounds of the sprouts during storage. In the main experiment, the effects of SA + Chitosan treatment on visual appearance, antioxidant activity, phytochemicals and antioxidant enzymes of the sprouts were monitored during storage. Visual appearance and pigments contents did not significantly change throughout storage. SA + Chitosan treated sprouts contained total phenols, ascorbic acid, antioxidant enzymes and antioxidant activity higher that control. Compared to SA and chitosan, SA + Chitosan enhanced total phenols, ascorbic acid, catalase activity and free radical scavenging activity during storage. In conclusion, SA + Chitosan could be a good mean enhancing phytochemicals of daikon sprouts during cold storage.

Physicochemical changes in fresh-cut wax apple (Syzygium samarangenese [Blume] Merrill & L.M. Perry) during storage.

Physicochemical changes, such as peel and flesh colours, total anthocyanin content, browning index, firmness, total soluble solid (TSS), titratable acidity (TA), sugar acid ratio (TSS/TA), antioxidant capacity, total phenolic content and ascorbic acid content, in fresh-cut Taaptimjan wax apple fruit stored at 4±2°C and 12±2°C for 7days were investigated. The skin of fresh-cut fruit stored at 4±2°C showed higher a(∗) value, chroma and total anthocyanin content and lower hue angle than those stored at 12±2°C. Lightness (L(∗) value) and whiteness index of the fresh-cut fruit flesh stored at 12±2°C showed significantly lower than those stored at 4±2°C which related to an significant increase in browning index. Firmness, total soluble solid, titratable acidity and sugar acid ratio did not significant changes during storage. Antioxidant capacity and total phenolic content increased throughout storage. Ascorbic acid content of the fresh-cut fruit stored at 4±2°C remained constant throughout storage whilst ascorbic content at 12±2°C decreased and was lower than that at 4±2°C. At 4±2°C antioxidant capacity and ascorbic acid content were higher than that stored at 12±2°C whilst there was no significant difference in total phenolic content. In conclusion, the reduction of whiteness index and the increase in browning index of fresh-cut wax apple flesh were the key factors affecting its quality and storage at 4±2°C could reduce the change in the flesh colour and maintained the peel colour and nutritional values of fresh-cut wax apple fruit during storage.