Tannins, present in numerous plants, exhibit a binding affinity for proteins. In this study, we aimed to exploit this property to reduce the concentration of allergenic egg white proteins. Tannins were extracted, using hot water, from the lyophilized powder of underutilized resources, such as chestnut inner skin (CIS), young persimmon fruit (YPF), and bayberry leaves (BBLs). These extracts were then incorporated into an egg white solution (EWS) to generate an egg white gel (EWG). Allergen reduction efficacy was assessed using electrophoresis and ELISA. Our findings revealed a substantial reduction in allergenic proteins across all EWGs containing a 50% tannin extract. Notably, CIS and BBL exhibited exceptional efficacy in reducing low allergen levels. The addition of tannin extract resulted in an increase in the total polyphenol content of the EWG, with the order of effectiveness being CIS > YPF > BBL. Minimal color alteration was observed in the BBL-infused EWG compared to the other sources. Additionally, the introduction of tannin extract heightened the hardness stress, with BBL demonstrating the most significant effect, followed by CIS and YPF. In conclusion, incorporating tannin extract during EWG preparation was found to decrease the concentration of allergenic proteins while enhancing antioxidant properties and hardness stress, with BBL being particularly effective in preventing color changes in EWG.
Diospyros , Tannins , Allergens , Skin , Gels , Plant Extracts
Wheat-dependent, exercise-induced anaphylaxis has no fundamental cure and requires patients to refrain from wheat consumption or to rest after eating. Although hypoallergenic wheat production by enzymatic degradation or thioredoxin treatment has been investigated, challenges still exist in terms of labor and efficacy. We investigated a hypoallergenic wheat product manufacturing technology that takes advantage of the property of tannins to bind tightly to proteins. Commercially available bread wheat (BW) and hypoallergenic wheat (1BS-18 "Minaminokaori", 1BS-18M) were used. Chestnut inner skin (CIS) was selected as a tannin material based on the screening of breads with added unused parts of persimmon and chestnut. Hypoallergenicity was evaluated using Western blotting. The effect of CIS addition on the antioxidative properties of bread was also measured. For both BW and 1BS-18M, CIS addition reduced the immunoreactivity of wheat allergens. Antioxidant activities increased with increasing CIS substitution. However, 10% CIS-substituted breads were substantially less puffy. Five percent CIS substitution was optimal for achieving low allergenicity, while maintaining bread quality. The strategy investigated herein can reduce allergies related to wheat bread consumption. In this study, the evaluation of hypoallergenicity was limited to instrumental analysis. In the future, we will evaluate hypoallergenicity through clinical trials in humans.
Antioxidants , Bread , Humans , Allergens , Flour
To promote the use of waxy barley bran, an underutilized resource, samples of waxy barley were divided into three parts: polished waxy barley powder (PWBP), inner bran layer powder (IBLP), and outer bran layer powder (OBLP). The color and appearance, general properties, minerals, vitamins, ß-glucan, antioxidant properties, and aroma of each part were compared. In terms of appearance and color, IBLP and OBLP appeared more yellow than PWBP; general components that were more abundant in IBLP and OBLP compared with PWBP were protein, fat, and ash. IBLP and OBLP had characteristically high values of Mg and Zn, monounsaturated and polyunsaturated fatty acids, vitamin B1, total polyphenol content, H-ORAC, and DPPH. In particular, the vitamin B1 content of OBLP was approximately 10 times higher than that of PWBP, and Mg and Zn content was more than five times higher than in PWBP. The ß-glucan content of IBLP and OBLP was lower than that of PWBP, but relatively high. GC-MS analysis revealed that hexanal was the aroma component common to all three samples, and the peak areas were in the order of PWBP > OBLP > IBLP.
The present study aimed to investigate the effect of the addition of tannins from unutilized resources on wheat allergen reduction, antioxidant properties, and quality by substituting 3%, 5%, and 10% of the flour with chestnut inner skin (CIS) and young persimmon fruit (YPF) powders to produce cookies. The enzyme-linked immunosorbent assay and Western blotting showed significantly lower wheat allergen content in CIS- or YPF-substituted cookies than in control cookies, and this effect was pronounced for CIS-substituted cookies. In addition, the tannin content and antioxidant properties of the CIS- or YPF-substituted cookies were markedly higher than those of the control cookies. Quality analysis of the CIS- and YPF-substituted cookies showed that the specific volume and spread factor, which are quality indicators for cookies, were slightly lower in the CIS- and YPF-substituted cookies than in the control cookies. Compared to the control, CIS substitution did not affect the breaking stress and total energy values of the cookies; however, YPF substitution at 10% increased these values. Color was also affected by the addition of CIS and YPF. The results suggest that the addition of CIS and YPF can reduce wheat allergens in cookies and improve tannin content and antioxidant properties.
This study has developed a production method for high-quality Genova tea with excellent antioxidant properties. The antioxidant properties of each part of the Genova basil plant (i.e., leaves, flowers, and stems) were determined; the leaves and flowers showed higher antioxidant values. We also investigated the effects of steaming time and drying temperature on the antioxidant composition and properties, color, and aroma using leaves with good yield potential and high antioxidant properties. The color showed excellent green color retention with freeze- and machine-drying at 40 °C without steam-heat treatment. Steaming for 2 min was effective in maintaining high values of total polyphenol content, antioxidant properties (1,1-diphenyl-2-picrylhydrazine and hydrophilic oxygen radical adsorption capacity), rosmarinic acid, and chicoric acid, and a drying temperature of ≤40 °C was recommended. Freeze-drying without steaming was the best method to retain all three of Genova's main aroma components, Linalool, trans-alpha-bergamotene, and 2-methoxy-3-(2-propenyl)-phenol. The method developed in this study can improve the quality of dried Genova products and be applied in the food industry, cosmetics, and pharmaceutical industries.
Non-astringent persimmon (Diospyros kaki Thunb.) paste is typically produced by treating astringent persimmon fruit with alcohol or dry ice (to remove tannins) followed by abrasion. However, considering the large yield of astringent persimmons harvested in a short time, this long, laborious method has hindered the use of persimmon paste in food processing. Herein, the addition of polysaccharides was used to produce a non-astringent persimmon paste while maintaining its quality. Among the nine evaluated polysaccharides, high- (HM) and low-methoxyl (LM) pectins, carrageenan, xanthan gum, and sodium alginate exhibited high astringency removal efficiencies. No astringency recurrence was observed after freezing when HM or LM pectin, guar gum, carrageenan, or sodium alginate were added. Moreover, the addition of HM pectin, or LM pectin, or sodium alginate prevented astringency upon heating. Additionally, guar, xanthan, tara gum, or carrageenan effectively inhibited syneresis. Thus, high-quality pastes could be easily and efficiently produced using a combination of polysaccharides.
The soluble tannins in Japanese persimmon gives it an unpleasant astringent taste, which can be removed using certain conventional methods. However, these methods are not very efficient and lead to the recurrence of astringency upon heating. Thus, the use of persimmon in processed food is severely limited. Although the effects of heating time and temperature on astringency recurrence have been explored in detail, the effect of the heating method used has not yet been clarified. Considering this, we subjected an astringency-removed paste to various heat treatments, namely, stir frying, boiling, and pressurization, and examined their effect on astringency recurrence. Soluble tannin contents were also determined, and sensory evaluation was conducted. It was observed that stir frying, which is accompanied by moisture evaporation, is superior with respect to the suppression of astringency recurrence and the prevention of syneresis compared with the other two methods. Moreover, the bright orange color and the gummy texture obtained upon stir frying are favorable for commercial purposes. Therefore, it is expected that these findings will lead to the significant improvement of astringent persimmon processing.
Chestnuts are widely cultivated for their edible portion (kernel), whereas the non-edible parts are discarded. To enable the utilization of the by-products of processed chestnuts, we separated them into green and brown burs, shells, inner skin, and leaves, and analyzed the bioactive properties of the ground components. We also created a composite paper, comprising the inner skin, and examined its deodorant properties. It was revealed that the inner skin had the highest functionality and showed potent antioxidant, antibacterial, and deodorant properties. Furthermore, when we produced a paper, containing 60% inner skin, and examined its deodorant properties, we found that it was highly effective in deodorizing ammonia and acetic acid gases. These results show that the inner skin of chestnuts is a promising material for developing hygiene and other products.
Fruit peels are often produced as a byproduct of processing and are usually disposed of as industrial waste. We conducted a study on the effective use of peels for the food industry using persimmons and mandarins as models. The production of persimmon and mandarin peel pastes, their flavor components, color, polyphenol contents, physical properties, and uses in foods (jam, cookies, and madeleines) were studied. The effects of heat treatment for sterilization, to effectively use persimmon and mandarin peels, were also investigated. The amount of water added to produce the optimum persimmon and mandarin peel pastes was 0.5× and 2.0× the weight of the respective peel samples. The main flavor components, as per GC-MS spectra of persimmon and mandarin peel pastes, were 4 and 1, respectively. The Folin assay showed the polyphenol contents of persimmon and mandarin pastes as 33.9 mg and 236.3 mg of catechin equivalent per 100 g of fresh fruit, respectively. The persimmon paste specifically improved the physical properties of cookies, whereas the mandarin paste was well suited to all the processed food forms. Heat treatment for sterilization decreased cohesiveness but increased breaking strength and adhesiveness in persimmon and mandarin pastes.
Molecular organogels, comprising small organic gelators in solvents, can be applied for dispersal of optical devices, such as emitters. Phenolic compounds and the surfactant bis(2-ethylhexyl) sulfosuccinate (AOT) are known examples of self-assembly organogels. However, conventional phenol + AOT gels in aromatic and acyclic alkane solvents are optically turbid, which is an obstacle for use as host materials in optical devices. In this study, a variety of aryl alcohol-AOT-solvent sets have been investigated systematically, and the correlation between the molecular architecture and optical transparency of the gels was considered. Accordingly, p-chlorophenol + AOT gels in cyclic alkane solvents were shown to form optically transparent gels. In contrast, aromatic and acyclic alkane solvents gave rise to turbid or opaque gels, even when utilizing the same gelators. AFM, NMR, SAXS, and FTIR were employed to determine the organogel structures. Consequently, we found that the gel transparency strongly depends on the size of the fibrous network of the gel, the structure of which is attributed to higher-order aggregates of the gelators. The average contour length and diameter of the fibrous network, lav and dav, respectively, were determined from AFM images. The transparent gels were shown to have lav = 4-9 µm and dav ≤ 0.3 µm, whereas the turbid gels had lav = 15 µm and dav = 0.4-0.6 µm. Such differences in the size of the fibrous network significantly affected the mechanical response of the gels, as shown by stress-strain measurements.
The effects of various light compositions on the levels of anthocyanin, rutin and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity in buckwheat (Fagopyrum esculentum Moench) sprouts were evaluated. Dark-grown 6-day-old buckwheat sprouts were irradiated with different sources of visible and ultraviolet (UV) light. Particularly, we examined the effect of UV-B at wavelengths of 260-320 nm, 280-320 nm, and 300-320 nm on the production of flavonoid compounds, using multiple fluorescent lights and cylinders that filter out certain portions of the UV-B. The results showed that irradiation with UV-B>300 nm increased the levels of anthocyanin and rutin, as well as the DPPH radical scavenging activity. When sprouts were irradiated with UV-B light at wavelengths of 260-300 nm, yellowing or withering occurred within 24h of irradiation, indicating that wavelengths in this range are detrimental to the growth of buckwheat sprouts.
Anthocyanins/analysis , Fagopyrum/chemistry , Fagopyrum/radiation effects , Free Radical Scavengers/analysis , Plant Extracts/analysis , Rutin/analysis , Seeds/growth & development , Fagopyrum/growth & development , Germination/radiation effects , Seeds/chemistry , Seeds/radiation effects , Ultraviolet Rays
Flavonoids are ingested by the general population as anti-oxidant and anti-inflammatory agents. In this study, we investigated the effects of myricitrin, a flavonoid rich in Myrica rubra leaf, upon anti-inflammatory action. Myrica rubra leaf extracts inhibited pro-inflammatory TNFα production in a macrophage cell line, Raw264.7 cells. We observed that the serum IgE levels in the leaf extract-treated DO11.10, a mouse allergy model, were down-regulated. HPLC was performed to demonstrate that M. rubra leaf extracts contain a large amount of myricitrin. We observed an inhibitory effect of HPLC-purified myricitrin on TNFα production in Raw264.7 cells. Thus, myricitrin may be of potential interest in the management of inflammatory conditions.
Flavonoids/chemistry , Flavonoids/pharmacology , Myrica/chemistry , Plant Extracts/chemistry , Plant Leaves/chemistry , Animals , Anti-Inflammatory Agents/pharmacology , Cell Line , Chemokine CCL5/metabolism , Chromatography, High Pressure Liquid , Enzyme-Linked Immunosorbent Assay , Immunoglobulin E/metabolism , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Molecular Structure , Tumor Necrosis Factor-alpha/metabolism
