Metabolic Variation among Fruits of Different Chili Cultivars (Capsicum spp.) Using HPLC/MS

Chilies are widely cultivated for their rich metabolic content, especially capsaicinoids. In our study, we determined individual sugars, organic acids, capsaicinoids, and total phenolic content in pericarp, placenta, and seeds of Capsicum annuum L., Capsicum chinense Jacq. and Capsicum baccatum L. by HPLC/MS. Dry weight varied in the cultivar ‘Cayenne’, with the first fruit having the lowest dry weight, with 4.14 g. The total sugar content and organic acid content did not vary among the fruits of all three cultivars. The cultivar ‘Cayenne’ showed differences in total phenolic and capsaicinoid content between fruits in the placenta, with the first fruit having the highest content of total phenolics (27.85 g GAE/kg DW) and total capsaicinoids (16.15 g/kg DW). Of the three cultivars studied, the cultivar ‘Habanero Orange’ showed the least variability among fruits in terms of metabolites. The content of dihydrocapsaicin, nordihydrocapsaicin, homocapsaicin, and homodihydrocapsaicin in the seeds of the second fruit was higher than that of the first fruit of the cultivar ‘Bishop Crown’. The results of our study provided significant insight into the metabolomics of individual fruits of the same chili plant. We have thus increased our understanding of how certain metabolites are distributed between fruits at different levels of the same plant and different parts of the fruit. This could be further investigated when chilies are exposed to different environmental stresses.

Role of Exogenous Melatonin, Hydrogen Sulfide and Nitric Oxide on Organic Acid Content of Eruca sativa L. under Salt Stress

Salt stress affects agricultural output by influencing numerous internal metabolisms in plants and disrupting physiological and biochemical activities such as photosynthesis, translocation, respiration, and growth stimulants. The role of exogenous melatonin, hydrogen sulfide and nitric oxide application on the organic acid contents of rocket plants under salt stress was examined in this study. Different salt doses (0, 150 and 250 mM NaCl) and exogenous applications (0, 50 and100 µM) were made to rocket plants under the greenhouse conditions. Plants leaves and roots exhibited a decline in the organic acid contents under salinity stress. Application of the amendments, however, was found significant in mitigating the negative effect of salt stress. Melatonin and hydrogen sulfide treatments had a stronger anti-salt action in the leaves. On the other hand, nitrous oxide role was more obvious in the roots followed by melatonin. With this, exogenous applications to the plant mitigated the harmful effects of salt stress on organic acid contents depending on the dose.

Comparison of Quality Characteristics of Commercial Kimchi Manufactured in Korea, China, and the United States

Recently, kimchi has been recognized as a healthy food worldwide, prompting increased interest in its health benefits and quality characteristics. Although commercial kimchi is manufactured in various countries, little is known about quality differences between the kimchi from different countries. To clarify differences in quality characteristics, minerals, free sugars, organic acids, free amino acids, and volatile compounds, commercial kimchi manufactured in Korea, China, and the United States were investigated. The composition of the microbial community and antioxidant activity were compared. Mineral and free sugar contents were high in Korean commercial kimchi, while the organic acid content was relatively low. The free amino acid content was markedly higher in Korean kimchi than that in kimchi manufactured in China and the United States. In addition, the volatile compound content differed between the kimchi produced in different countries. Considering the microbial communities, Leuconostoc and Weissella were more abundant in commercial kimchi from Korea than that from China or the United States. Commercial kimchi in Korea showed the highest antioxidant activity. These results support the high quality and antioxidant activity of commercial kimchi manufactured in Korea, emphasizing its importance in the global kimchi industry.

Influence of Green Light Added with Red and Blue LEDs on the Growth, Leaf Microstructure and Quality of Spinach (Spinacia oleracea L.)

The aim of this study was to investigate the effects of green light, added with red and blue LEDs, on the growth, leaf microstructure and quality of spinach plants. Plants were transplanted and grown hydroponically for 30 days under different combinations of red:blue with a 4:1 ratio (R4B1), red:blue:green with a 5:2:3 ratio (R5B2G3) and red:blue:green with a 1:1:1 ratio (R1B1G1), at a 190 µmoL m−2·s−1 photosynthetic photon flux density (PPFD). The results showed that green light, added to red and blue LEDs at a reasonable ratio, could reduce the growth, leaf microstructure and quality of spinach plants, but not the organic acid content. The highest values for the growth parameters, photosynthetic pigments, leaf structure characteristics and quality of the spinach plant were observed for the R4B1 treatment, but not for the organic acid content. Therefore, our results suggest that green light added to red and blue LEDs at a reasonable ratio is not suitable for the growth of spinach.

Manufacture of Mikania micrantha vinegar and investigation of its repellent activity for Forcipomyia taiwana

Crude vinegar was prepared from Mikania micrantha plants using a steel kiln. The ether-extracted vinegar and acidic, phenolic, and neutral fractions were obtained by the partition method. The fundamental properties of crude vinegar, including its fractions applied to repel biting midges (Forcipomyia taiwana), were investigated. Results indicated that the crude vinegar had a moisture content of 91%, Gardner color value of 11.2, a reddish-brown color, specific gravity of 1.0164, pH of 5.36, organic acid content of 2.50%, and soluble tar content of 0.78%. In ether-extracted vinegar of M. micrantha, the acidic component was the major ingredient, followed by the neutral, phenolic, and nitrogenous components. The main organic compounds of the acidic, phenolic, nitrogenous, and neutral components were acetic acid, phenol, 3-pyridinol, and 2-furanmethanol, respectively. The results also demonstrated that the crude vinegar, ether-extracted vinegar, and the phenolic and neutral fractions effectively repelled biting midges, with absolute repellent times of 49, 87, 83, and 99 min, respectively. The repellent activity of ether-extracted vinegar and the phenolic and neutral fractions of M. micrantha vinegar on biting midges was higher than that of a commercial repellent agent (named Dinling) with absolute repellent time of 61 min.

Exogenous 2,4-Epibrassinolide Treatment Maintains the Quality of Carambola Fruit Associated With Enhanced Antioxidant Capacity and Alternative Respiratory Metabolism

Brassinosteroids act by delaying fruit ripening. The effects of different concentrations of 2,4-epibrassinolide (eBL) treatments on carambola fruit ripening were investigated. The results show that treatment of 2.8 mg L–1, eBL with 10 min effectively delays ripening and maintains the quality of carambola fruit. This is achieved by retarding color changes and firmness losses while maintaining high level of soluble protein content and vitamin C, and low organic acid content. eBL-delayed senescence may be due to the inhibition of respiration rate and enhanced antioxidant system. It is noteworthy that eBL treatment markedly reduces the content of fructose-6-phosphate (6-P-F) and enhances the activity of cytochrome oxidase (CCO), and the total activity of glucose-6-phosphate dehydrogenase (G-6-PDH) and 6-phosphate gluconate dehydrogenase (6-PGDH). eBL treatment induces the IAA and GA contents but reduces that of ABA. In general, senescence retardation and quality improvement by eBL treatment may be due to the enhanced antioxidant capacity and altered respiratory pathways.

Substitution of potassium sorbate preservative by fermented wheat flour in the production of biscuits. Safety, nutritional and sensory characteristic potentials

In this study, the potential of the substitution of the conventional preservative potassium sorbate by fermented wheat flour as an alternative was analysed. The organic acid content and antibacterial activity of preservatives and the macronutrient characterisation were tested, as was the sensory evaluation of biscuits with added conventional and alternative preservatives. The results show that the fermented wheat flour contains secondary fermentation metabolites (e.g. acetic, lactic and pyruvic acids). Both fermented wheat flour and potassium sorbate have antibacterial effects against Staphylococcus aureus, Bacillus cereus and Bacillus subtilis. The sensory evaluation demonstrated that fermented wheat flour in the recommended concentration range had no impact on sensory quality. Therefore, fermented wheat flour represents a potential substitution for conventional potassium in bakery products.

Organic acid composition and consumer acceptability of fermented fish produced from black tilapia (Oreochromis mossambicus) and Javanese carp (Puntius gonionotus) using natural and acid-assisted fermentation

Ikan pekasam is an example of traditional fermented food products in Malaysia, prepared from freshwater fish such as black tilapia (Oreochromis mossambicus) and Javanese carp (Puntius gonionotus), salt and ground roasted rice, which is added as the only source of carbohydrate. However, some producers add tamarind (Tamarindus indica) pulp and/or dried slices of Garcinia atroviridis to assist the fermentation process. In this study, there was no correlation detected between pH value, titratable acidity (% lactic acid), salt concentration, organic acid composition and the consumer acceptability of ikan pekasam commercial samples made of black tilapia as well as Javanese carp. The organic acid composition in both natural and acid-assisted fermented ikan pekasam from black tilapia and Javanese carp were compared. The results obtained showed that lactic acid was the major organic acid detected, followed by succinic acid and acetic acid. The addition of tartaric and/or garcinia acids was proven to reduce the fermentation time. Therefore, the addition of acid has assisted the fermentation process by increasing the total organic acid content, mainly lactic acid. Moreover, the 9-point hedonic scale showed that ikan pekasam made of Javanese carp had higher overall acceptability due to tender flesh/muscle texture compared to black tilapia regardless of the fermentation process and organic acid content

Investigation on the Organic Acid Content inside the Storage of a Woodblock Print Collection and Evaluation on the FFU System as a Mitigation Strategy

This paper describes an investigation on the storage environment of an Edo period woodblock print collection in terms of volatile organic acid content, using active air sampling and precision gas detector tubes that can measure organic acid emissions in the low microgram range, and evaluates an organic acid mitigation method based on the fan filter unit (FFU) system. Ion-exchange chromatography method was also employed for estimation of acetic and formic acid ratio. Findings revealed an organic acid-concentrated microclimate inside the storage box, nevertheless, the off-gassing rates of the woodblock prints were low, with the exception of a print positioned in the middle of the stack. The acetic acid/formic acid ratio was similar between the storage room environment and inside the storage box, but comparatively higher levels of formic acid were identified in the mulberry paper folder housing the prints. Finally, the FFU system was able to reduce organic acid concentrations inside the storage box for a 5-month observation period, but it did not eliminate the tendency of the storage materials to create organic acid-concentrated microclimates.

Effects of Different Packaging Materials on Storage Quality of Crisp Plum

This experiment uses “Bashan crisp plum” as the material, uses nano-bags and spontaneous modified atmosphere preservation bags for packaging, combined with 1-MCP fumigation treatment, and stores in a cold storage at 1±1.5℃. The physiological and biochemical measurements are measured every 15 days Indicators to discuss the low-temperature storage effects of different packaging materials. The results showed that the use of nano-bags and air-permeability of 3000mL/bag/24h modified atmosphere packaging can reduce fruit rot, delay the yellowing of the peel, better maintain the fruit texture and organic acid content, and better maintain the original fruit.