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Blueberries are vulnerable to chilling injury (CI). This can lead to limited longevity when they are subjected to cold storage conditions. This study investigated the effectiveness of a preharvest spray containing 0.02% hexanal in reducing CI and improving the postharvest storage quality of 'Star' and 'Biloxi' blueberries. The blueberries were stored for a period of 5 weeks at 2 °C and in 90% relative humidity (RH). The findings revealed that the preharvest hexanal spraying of both cultivars delayed senescence by mitigating CI, as evidenced by the bolstering of the antioxidant defense system through increased superoxide dismutase (SOD), ascorbate peroxidase (APX), peroxidase (POD), catalase (CAT), and phenylalanine ammonia lyase (PAL) enzyme activity. The treated fruit also maintained elevated levels of total phenol content (TPC), total flavonoids (TFC), and vitamin C, demonstrating enhanced free radical scavenging capacity (FRSC), while exhibiting reduced polyphenoloxidase (PPO) activity, and reduced malondialdehyde (MDA), and H2O2 content in comparison with the control group. The preharvest hexanal treatment also suppressed fruit softening by maintaining greater firmness and higher membrane stability index (MSI) scores, inhibiting the activity of polygalacturonase (PG), pectinmethylesterase (PME), xylanase, and α‐amylase, and reducing microbial counts (MC) and incidence of decay (DI) in comparison with the control. Preharvest hexanal treatment also improved the overall storage quality by reducing weight loss, total soluble solids (TSS), pH, and the TSS/acid ratio, while increasing titratable acidity (TA) in comparison with the control during cold storage. The findings suggest that hexanal, as a preharvest application, delays senescence effectively and preserves overall quality by enhancing cold tolerance through antioxidant defense mechanisms in blueberry storage under cold conditions. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The black wolfberry (Lycium ruthenicum) belongs to the Solanaceae family. The genus Lycium comprises 87 recognized species and is distributed in arid and semi-arid regions of temperate to subtropical zones in the world. At present, China is the greatest global producer and supplier of wolfberry products. The goji berry has recently became one of the most popular fruits in Turkey due to its health-beneficial compounds such as phenolic compounds (phenolic acids and flavonoids), carotenoids, tocopherol, ascorbic acid and antioxidant properties. Lycium fruits have been used as a remedy since ancient times in Asian countries, especially in China, for their emmenagogue, diuretic, antipyretic, tonic, aphrodisiac, hypnotic, and hepatoprotective effects. The purpose of this paper is to determine the biochemical characteristics (namely total phenolic and anthocyanin contents, as well as the total antioxidant capacity) of black wolfberries grown under the Aksaray ecological conditions.

The pistachio (Pistacia vera L.), a small nut tree belonging to the Anacardiaceae family, is extensively grown in Turkey, which is one of the leading world producers of pistachios. Kernel color is an important parameter for the evaluation of raw pistachios containing chlorophylls a and b as the major pigments. Moreover, kernel color is one of the most important quality attributes evaluated by consumers, producers and distributors. Chlorophylls a and b are the predominant pigments responsible for the green color of pistachios. Pigment concentrations are influenced by a number of factors such as geographic origin, ripeness degree, storage conditions and processing methods. Chlorophylls are sensitive to heat and can be degraded into pheophytins and pyropheophytins. Therefore, the purpose of this paper is to determine the chlorophyll content of the 'Uzun' pistachio cultivar (Pistacia vera L.) using the spectrophotometric methods and different solvents.

The 'Sweet Lemon' and 'Interdonato' lemon varieties were evaluated based on their antioxidant activity, sugar, total phenol and citric, succunic and L-ascorbic acid content in the present study. The total phenol content (TPC) of 'Sweet Lemon' and 'Interdonato' lemon fruit juice were about 123.19 mgGAE/100g and 81.76 mgGAE/100g respectively. The FRAP content were detected as 146.86 μmoltrolox/g in 'Sweet Lemon' while 106.78 μmoltrolox/g in 'Interdonato' lemon variety. However the trolox equivalent antioxidant capacity (TEAC) assay, which measures the reduction of the ABTS radical cation by antioxidant ABTS content was 96.25 μmoltrolox/g and 79.09 μmoltrolox/g respectively. Fructose was 3.26 %, sucrose was 0.19 % and glucose was 2.44 % in 'Sweet Lemon' variety. Therefore, fructose content was 1.22 %, sucrose was 0.19 % and glucose was 0.80 % in 'Interdonato' lemon variety. The results indicated that 'Sweet Lemon' fruit juices are rich in FRAP, ABTS, TPC and fructose, succinic and L-ascorbic acid content compared to 'Interdonato' lemon. The organic acids (citric acid, L-Ascorbic acid and succinic acid) values of both 'Sweet Lemon' and 'Interdonato' are 0.24-8.86 %, 62.25-55.50 mg/100g and 1.93-0.09 %, respectively. The present study revealed that the healthy properties of lemon fruits have been attributed to L-ascorbic acid and phenolic compounds, mainly to antioxidant content.

Pretreatment is extremely required in lignocellulosic bioethanol production to improve enzymatic digestibility of biomass by disrupting lignin structure, reducing cellulose crystallinity, and increasing biomass porosity. The aim of this study was to evaluate the effects of different chemical pretreatments (dilute acid, alkaline, and sequential dilute acid/alkaline) for the conversion of miscanthus biomass to fermentable sugars. Pretreatments were performed in an autoclave at 121 °C for 30 and 60 min. Sequential dilute sulfuric acid (H2SO4)/sodium hydroxide (NaOH) pretreatments caused the highest lignin removal (80.2–93.1%) but the lowest solid recovery (28.7–34%) among the pretreatments. Additionally, the dilute H2SO4 pretreatments induced significantly lower hemicellulose recovery than the NaOH and lime (Ca(OH)2) pretreatments. On the other hand, the significantly highest theoretical ethanol yield (206.8 mg g–1 raw material) was achieved when the biomass was subjected to 1% NaOH (w/v) pretreatment for 30 min, primarily due to its high sugar production (613.3 mg g–1) and moderate solid recovery (66.1%). These results indicated that the NaOH pretreatment was the most promising option among the chemical pretreatments tested to ensure sustainable bioethanol production from miscanthus. [ABSTRACT FROM AUTHOR]

Growth and production of carotenoid in three Dunaliella species (Dunaliella salina (Dunal) Teodoresco, Dunaliella bardawil Ben-Amotz & Avron and Dunaliella sp.) were investigated using flat-plate photobioreactors in outdoor conditions with two optical paths (3 cm and 5 cm). The experiment was conducted in duplicate and lasted four weeks during which light intensity, temperature, pH and optical density were checked daily. The pigment production (total carotenoid and chlorophyll a) was monitored every two days. To induce an additional stress besides temperature and light intensity, two different salt concentrations were used, i.e. 6% and 8% NaCl. The highest growth in all treatment groups was noticed for Dunaliella sp. followed by D. bardawil and D. salina. D. salina produced a higher content of carotenoid concentrations corresponding to 5 cm/8% and 5 cm/6% groups; 779.102 ± 0.434 μg.mL−1 and 694.326 ± 0.098 μg.mL−1 were registered at the end of the experiment. The same species had also greater content of β-carotene. [ABSTRACT FROM AUTHOR]