Determination of morpholine residues in apples by liquid chromatography tandem mass spectrophotometry (LC-MS/MS)

Morpholine is an emulsifier that is normally used as a protective wax coating on the surfaces of fruit and vegetable. In order to keep fruits fresh, extend their shelf-life, against insect and fungal contamination for a long time, morpholine has been widely applied despite of the reported carcinogenic potential in previous studies and export prohibition in many countries. A highly sensitive method has been developed for the determination of this food additive in fruits using ultra-performance liquid chromatography tandem mass spectrophotometry. By using 1 % acetic acid in methanol for extraction and analyzing with binary ammonium formate 20 mM and acetonitrile, the method has been applied successfully to determine morpholine residues in apple samples collected at local markets in Hanoi, Vietnam. The good coefficient correlation was achieved in the linear range of 5 - 300 µg/L (R2 = 0.9998). The low limit of detection (LOD) and limit of quantification (LOQ) were 2 µg/kg and 5 µg/kg, respectively. The recoveries of morpholine were 83 – 108 % over three spike levels 20 - 60 μg/L for apple, peel and pulp matrices. The repeatability (RSDr %) was 1.1 % for apple matrix, 2.36 % for peel and 3.67 % for pulp. The reproducibility values (RSDR %) were 1.49, 3.50 and 4.08 % for apple, peel and pulp, respectively. This method could be further performed in different type of fruit and vegetable comiditities to determine the morpholine content.

Treatments to prolong the postharvest life of Heliconia wagneriana Petersen

Tropical flowers have a growing market due to their exotic appearance and thus postharvest techniques are necessary to prolong their shelf life. The objective of this study was to evaluate the effectiveness of wax and salicylic acid (1 mM) in reducing chilling injury and increase the vase life in stems of Heliconia wagneriana stored at low temperature. For that, 120 stems were harvested in a commercial area. From these, 60 stems were waxed and air-dried; while 60 unwaxed stems served as controls. Then 2 groups of 48 stems from both treated and control were cold-stored at 13 °C and 84 % RH for 5 and 10 days. After storage, the stems were placed either in salicylic acid solution (1 mM) or tap water. The remaining stems (12 waxed and 12 control) were kept at room temperature. The variables evaluated were anatomical characteristics, fresh weight loss, solution uptake, vase life, enzymatic activity (polyphenol oxidase and peroxidase), and membrane integrity. The wax coating maintained the fresh weight and extended the vase life of the stored stems under room temperature for up to 2 more days. The vase life of the cold-stored stems of 5 and 10 days was extended by 3 and 2 more days respectively, as compared to the control. No significant effect was observed for the use of salicylic acid (1 mM). The bracts tissue of the waxed stems showed lower enzymatic activity, reflected in lower oxidative stress compared to the control. Tropical species as heliconia present a very low water absorption, then the use of wax coating is recommended to preserve the turgidity and shelf life of the stems.

High-yielding cultivar of spring turnip rapeseed of “000” type Gratsiya

The spring turnip rapeseed cultivar Gratsiya was developed at the Siberian experimental station – a branch of V.S. Pustovoit All-Russian Research Institute of Oil Crops by multiple individual and family selections from high-yielding, yellowseeded forms of the German cultivar Eldorado. In 2020, we isolated elite plant in the selection nursery by the main agronomic valuable traits: early maturity, high productivity, resistance to lodging, yellow seed color, low content of glucosinolates in the seeds and erucic acid in the oil. According to the results of three years competitive trials (2018–2020), 12 promising numbers with a growing season of 66–70 days were evaluated and a promising high-yielding number 31119 – the cultivar of type “000” Gratsiya was isolated. The cultivar of spring turnip rapeseed Gratsiya exceeded the standard cultivar Pobeda in seed yield by 0.21 t/ha and in oil yield by 0.08 t/ha. By the main agronomic traits, the cultivar Gratsiya differs from the standard one in lower content of glucosinolates in seeds (14.6 µmol/g) and erucic acid in oil (0.43 %). Seedlings are green, without wax coating, the plant is semi-dense, medium-branched, plant height of 120– 135 cm. The fruit is a pod, 5–7 cm long. Seeds are yellow, with an addition of brown – up to 2 %. Thousand-seed weight is 2.5–2.8 g. It is moderately drought-resistant, has uniform ripening, is suitable for mechanical harvesting, and is recommended for cultivation throughout the Russian Federation because of its early maturity.

Effects of Superhydrophobic Sand Mulching on Evapotranspiration and Phenotypic Responses in Tomatoes (Solanum lycopersicum) under Normal and Reduced Irrigation

Irrigated agriculture in arid and semi-arid regions is a vital contributor to the global food supply; however, these regions endure massive evaporative losses that are compensated by unsustainable freshwater withdrawals. Plastic mulches have been used to curtail evaporation, improve water-use efficiency, and ensure food and water security, but they are non-biodegradable and their disposal is unsustainable. We recently developed superhydrophobic sand (SHS), which comprises sand grains with a nanoscale wax coating that could offer a more sustainable mulching solution. Here, the effects of adding a 1.0 cm-thick layer of SHS mulch on the evapotranspiration and phenotypic responses of tomato (Solanum lycopersicum) plants are studied under normal and reduced irrigation. Under both irrigation regimes, SHS mulching suppressed evaporation and enhanced transpiration by 78% and 17%, respectively relative to the bare soil. Overall, SHS mulching enhanced root xylem vessel diameter, stomatal aperture, stomatal conductance, and chlorophyll content index by 21%, 25%, 28%, and 23%, respectively. Total fruit yields, total dry mass, and harvest index increased in SHS-mulched plants by 33%, 20%, and 16%, respectively than in bare soil. These findings demonstrate the potential of SHS to boost irrigation efficiency in water-limited environments and provide mechanistic insights behind yield enhancement by SHS mulching.

Self-assembly of Eucalyptus gunnii wax tubules and pure ß-diketone on HOPG and glass

Eucalyptus trees and many plants from the grass family (Poaceae) and the heather family (Ericaceae) have a protective multifunctional wax coating on their surfaces made of branched ß-diketone tubules. ß-diketone tubules have a different size, shape, and chemical composition than the well-described nonacosanol tubules of the superhydrophobic leaves of lotus (Nelumbo nucifera). Until now the formation process of ß-diketone tubules is unknown. In this study, extracted wax of E. gunnii leaves and pure ß-diketone were recrystallized on two different artificial materials and analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM) to study their formation process. Both the wax mixture and pure ß-diketone formed tubules similar to those on E. gunnii leaves. Deviating platelet-shaped and layered structures not found on leaves were also formed, especially on areas with high mass accumulation. High-resolution AFM images of recrystallized ß-diketone tubules are presented for the first time. The data showed that ß-diketone tubules are formed by self-assembly and confirmed that ß-diketone is the shape-determining component for this type of tubules.

Hog plums: Its importance, potentials and future prospects

Hog plums, scientifically known as Spondias mombin are medicinal plants that are rich in nutrients and antioxidants, and are of great importance in the food/agricultural industries and the health sector. In the food industries, it is an important fruit crop that can be eaten raw, juiced and processed for making jam, ice cream and jellies, and also provides farmers an alternative feeding material for lactating ruminants to help in galactogenesis and lactopoiesis. In the health sector, hog plums fruit, leaves and stem extract possess antimicrobial, cytotoxic, anti-tyrosinase, diuretic and febrifuge activities for the treatment of certain disease conditions, and it can be effectively preserved by wax coating of the fruits. Methanolic extract of Spondias contain methyl gallate, a substance that has the potential to facilitate apoptotic cell death in human glioblastoma, lung, and breast cancer Hog plums are also rich in vitamins, it strengthens the immune system, protects against heart disease, and stimulates the production of collagen which keeps the body healthy. It is a plant that has obvious and promising health benefits, and as such more research into its properties is advisable. Preservation of hog plum can be achieved by wax coating, retardation of ripening and senescence, and application of growth regulators.

Carnauba wax coating preserves the internal quality of commercial eggs during storage

The objective of this study was to evaluate the internal quality and lipid oxidation of eggs coated with a carnauba wax-based product at different concentrations and stored for up to 28 days under two temperatures. For analysis of internal quality, the eggs were assigned to a completely randomized 3 x 4 factorial design (uncoated eggs (control); eggs coated with carnauba wax at 12% concentration (Aruá®); eggs coated with carnauba wax at 15% concentration (Aruá®); four storage periods - 7, 14, 21, and 28 days). Fifteen eggs from each treatment were evaluated in each storage period, with each egg representing one replicate, i.e., 300 eggs per storage temperature (10 and 25°C). Egg weight loss, yolk percent (%), albumen percent (%), Haugh unit, yolk index, and specific gravity were calculated. Lipid oxidation of the egg yolk was measured by thiobarbituric acid reactive substances (TBARS), using 10 eggs at time 0 (fresh) and 30 eggs in each storage period (7, 14, 21, and 28 days), in triplicate, under only one storage temperature (25°C). A total of five pools, consisting of two eggs each, were used for each treatment. Each pool was considered a replicate, and each treatment consisted of five replicates. The weight loss of the eggs stored at 10°C and 25°C during the storage period was, on average, 46.1% and 37.3% lower for the eggs coated with carnauba wax than in uncoated eggs, respectively. Overall, coated eggs, regardless the concentration of the wax (12 or 15%) had higher Haugh units, specific gravity, and yolk index than uncoated eggs, in both temperatures (10 and 25°C). Uncoated and coated eggs showed similar lipid oxidation values regardless of the storage period. On the other hand, eggs coated with solutions containing 15% wax showed less oxidation than eggs coated with 12% wax. The coating of commercial eggs with carnauba wax, both at concentrations of 12 and 15%, was effective in maintaining their internal quality during storage at both storage temperatures (10 and 25°C). Eggs stored at 25°C had lower quality traits during storage compared with eggs kept under refrigeration. Coating eggs with wax did not minimize the oxidative processes in the egg yolk.

Effect of Wax Coating on Post Harvest Quality Parameters and Sensory Characteristics of Oranges

Various wax preservatives (Aloe vera gel, polyethene film, Candle wax, and Control) were evaluated to determine their effect on sensory characteristics (color, texture, and overall acceptability) of sweet oranges (Citrus sinensis) preserved at ambient temperature for 21 days. The goal of this study is to extend the shelf life of harvested oranges by the application of Aloe Vera wax, paraffin wax and polyethylene film to evaluate the treatment that will enhance physico-chemical parameters as well sensory characteristics. Other parameters examined were weight loss, pH, Total sugar (brix), Total solid, ash, moisture and vitamin C content. Results indicated that weight loss was observed across samples, however the weight loss was least with Aloe vera coated oranges which showed a significantly higher weight value (170.57 gm) after 3 weeks of storage. Sensory profile results showed that Aloe vera coated oranges had higher color and overall acceptability scores of 6.65 and 7.20 respectively. Also, the aloes vera coated oranges showed higher vitamin C content (24.15 mg/100 ml), indicating that oranges coated with Aloe vera gel prevented the deterioration of vitamin C during the period of storage.

Postharvest management of Heliconia psittacorum x H. spathocircinata cv. Tropics

Objetive: Evaluate different techniques to prolong the postharvest life of Heliconia psittacorum x H. spathocircinata cv. Tropics. Design/methodology/approach: Two experiments were carried out; in the first it was evaluated the effect of five pulse solutions [(T1 = control (water); T2 = Hydraflor® 100 (0.5 g L-1); T3 = Hydraflor® 100 (0.5 g L-1) + sucrose (5% w/v); T4 = salicylic acid (1mM) and T5 = salicylic acid (1mM) + sucrose (5% w / v)] prior to storage at 11 ° C and 85 % RH for 10 d. In the second experiment, a wax coating was applied to the heliconia bracts and then maintain at 13 °C and 84% RH for 10 d; after storage the stems were placed in water or salicylic acid solution (1 mM). The results were analyzed by a completely randomized design, 10 replicates were used per treatment, one stem was one experimental unit. An ANOVA and a means comparison test (Tukey, ?=0.05) were performed with the SAS version 9.4. Results: The anatomy of heliconia stems determines their vase life, since they have wide xylem vessels susceptible to cavitation, for which the absorption of water is limited, also and non-functional stomata in the bracts, which increase the loss of moisture from the tissue. The use of pulse solutions or preservatives has little effect in prolonging the life of heliconia stems. Therefore, the application of wax creates a physical barrier that maintains the turgor of the stems, reduces oxidation, maintaining the bracts quality and increased the total postharvest life for 6 d more than the control stems. Study limitations/implications: No limitations were found in this study Findings/conclusions: The postharvest life of heliconia is conditioned by the loss of turgor and low water absorption, which leads to an early wilting of the inflorescences. The application of pulse solutions or preservatives have little effect in prolonging the life of the vase, so the most suitable technique to preserve the quality of the stems is waxing.