Screening the Key Region of Sunlight Regulating the Flavonoid Profiles of Young Shoots in Tea Plants (Camellia sinensis L.) Based on a Field Experiment.

Both UV and blue light have been reported to regulate the biosynthesis of flavonoids in tea plants; however, the respective contributions of the corresponding regions of sunlight are unclear. Additionally, different tea cultivars may respond differently to altered light conditions. We investigated the responses of different cultivars ('Longjing 43', 'Zhongming 192', 'Wanghai 1', 'Jingning 1' and 'Zhonghuang 2') to the shade treatments (black and colored nets) regarding the biosynthesis of flavonoids. For all cultivars, flavonol glycosides showed higher sensitivity to light conditions compared with catechins. The levels of total flavonol glycosides in the young shoots of different tea cultivars decreased with the shade percentages of polyethylene nets increasing from 70% to 95%. Myricetin glycosides and quercetin glycosides were more sensitive to light conditions than kaempferol glycosides. The principal component analysis (PCA) result indicated that shade treatment greatly impacted the profiles of flavonoids in different tea samples based on the cultivar characteristics. UV is the crucial region of sunlight enhancing flavonol glycoside biosynthesis in tea shoots, which is also slight impacted by light quality according to the results of the weighted correlation network analysis (WGCNA). This study clarified the contributions of different wavelength regions of sunlight in a field experiment, providing a potential direction for slightly bitter and astringent tea cultivar breeding and instructive guidance for practical field production of premium teas based on light regimes.

Combination of Selenium and UVA Radiation Affects Growth and Phytochemicals of Broccoli Microgreens.

Addition of selenium or application of ultraviolet A (UVA) radiation for crop production could be an effective way of producing phytochemical-rich food. This study was conducted to investigate the effects of selenium and UVA radiation, as well as their combination on growth and phytochemical contents in broccoli microgreens. There were three treatments: Se (100 µmol/L Na2SeO3), UVA (40 µmol/m2/s) and Se + UVA (with application of Se and UVA). The control (CK) was Se spraying-free and UVA radiation-free. Although treatment with Se or/and UVA inhibited plant growth of broccoli microgreens, results showed that phytochemical contents increased. Broccoli microgreens under the Se treatment had higher contents of total soluble sugars, total phenolic compounds, total flavonoids, ascorbic acid, Fe, and organic Se and had lower Zn content. The UVA treatment increased the contents of total chlorophylls, total soluble proteins, total phenolic compounds, and FRAP. However, the Se + UVA treatment displayed the most remarkable effect on the contents of total anthocyanins, glucoraphanin, total aliphatic glucosinolates, and total glucosinolates; here, significant interactions between Se and UVA were observed. This study provides valuable insights into the combinational selenium and UVA for improving the phytochemicals of microgreens grown in an artificial lighting plant factory.

Gamma-Irradiated Chrysin Improves Anticancer Activity in HT-29 Colon Cancer Cells Through Mitochondria-Related Pathway.

Irradiation technology can improve the biological activities of natural molecules through a structural modification. This study was conducted to investigate the enhancement of the anticancer effects of chrysin upon exposure to gamma irradiation. Gamma irradiation induces the production of new radiolytic peaks simultaneously with the decrease of the chrysin peak, which increases the cytotoxicity in HT-29 human colon cancer cells. An isolated chrysin derivative (CM1) exhibited a stronger apoptotic effect in HT-29 cells than intact chrysin. The apoptotic characteristics induced by CM1 in HT-29 cells was mediated through the intrinsic signaling pathway, including the excessive production of included reactive oxygen species, the dissipation of the mitochondrial membrane potential, regulation of the B cell lymphoma-2 family, activation of caspase-9, 3, and cleavage of poly (adenosine diphosphate-ribose) polymerase. Our findings suggest that CM1 can be a potential anticancer candidate for the treatment of colon cancer.

UV-B radiation increases anthocyanin levels in cotyledons and inhibits the growth of common buckwheat seedlings.

The impact of short-term UV-B treatment on the content of individual flavonoids and photosynthetic pigments in cotyledons and the growth of common buckwheat (Fagopyrum esculentum Moench) seedlings was investigated. Seeds of four common buckwheat cultivars were germinated in darkness over a period of 4 days and acclimatized for 2 days under a 16/8 h light/dark photoperiod at 24/18 °C day/night, and exposure to 100-120 µmol ∙ m-2 ∙ s-1 of photosynthetically active radiation (PAR). Seedlings were divided into three batches, including two batches subjected to different doses of UV-B (5 W ∙ m-2 and 10 W ∙ m-2, one hour per day) for 5 days, and a control group exposed to PAR only. Exposure to UV-B increased anthocyanin levels in the cotyledons of all examined cultivars, it inhibited hypocotyl elongation, but did not affect the content of photosynthetic pigments. Flavone concentrations increased in cv. Red Corolla and Kora, remained constant in cv. Panda and decreased in cv. Hruszowska. Exposure to UV-B decreased rutin levels in cv. Hruszowska, but not in the remaining cultivars. Cultivars Hruszowska, Panda and Kora appeared to be less resistant to UV-B than Red Corolla. Higher resistance to UV-B radiation in Red Corolla can probably be attributed to its higher content of anthocyanins and rutin in comparison with the remaining cultivars.

Effects of Light Intensity on the Growth, Photosynthetic Characteristics, and Flavonoid Content of Epimedium pseudowushanense B.L.Guo.

Epimedium pseudowushanense B.L.Guo is used in traditional medicine as an aphrodisiac and to strengthen muscles and bones. Several recent reports have shown that flavonoids from Epimedium also significantly affect the treatment of breast cancer, liver cancer, and leukemia. However, few studies have examined the medicinal-ingredient yield of Epimedium, a light-demanding shade herb, under different light intensities. To investigate the effects of light intensity on medicinal-ingredient yields, Epimedium was exposed to five levels of light intensity until harvest time. Leaf dry biomass under L4 was the highest among different light treatments. L4 was also associated with the highest net photosynthetic rate. Quantification of epimedin A, epimedin B, epimedin C, and icariin showed that L3 produced the highest amount of epimedin C, and that flavonoid content responded to light levels differently. Results indicated that L3 and L4 were the optimal light levels for medicinal-ingredient yield.

Gamma radiation effects on peanut skin antioxidants.

Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative properties when added to soybean oil.

Chemical composition and antioxidant properties of γ-irradiated Iranian Zataria multiflora extracts.

CONTEXT: Irradiation is the process of exposing food such as herbal plant to ionizing radiation to destroy microorganisms. Zataria multiflora Boiss (Lamiaceae), known as Avishan-e-Shirazi in Persian, is a thyme-like plant that grows naturally in central and southern parts of Iran and is used in traditional folk medicine. OBJECTIVE: In this study, the effects of γ-radiation on chemical composition and antioxidant properties of Z. multiflora were investigated. MATERIALS AND METHODS: The plants were first irradiated with Co60 source (0, 10, and 25 kGy) and then subjected to Clevenger extraction to obtain essential oils. The composition of the oil was analyzed by a gas chromatography and compared with samples pretreated under different conditions. In parallel, the hydroalcoholic extract was prepared and used for measuring flavonoid content. Thereafter, the free-radical scavenging and antioxidant properties of essential oils and hydroalcoholic extract were examined. RESULTS: Despite the minor change in the individual oil constituents, the total percentage of the main components remained unaffected before and after irradiation (~95%). In addition, the total flavonoid content of hydroalcoholic extract was also unchanged due to irradiation (~32 mg QE/g extract). The high radical scavenging activity of the oil (~67%) and hydroalcoholic extract (~71%), in addition, the antioxidant properties of the oil (~91%) and hydroalcoholic extract (~95%), were unaffected after irradiation. DISCUSSION AND CONCLUSIONS: These findings may suggest the sustainability of Z. multiflora extract properties pretreated with γ-radiation. With a view to its antioxidant applications, resistance of Z. multiflora and its properties against radiation effects are promising findings.

Optimization of ultrasound-assisted extraction (UAE) of flavonoids compounds (FC) from hawthorn seed (HS).

Hawthorn seed (HS), an important by-product of the Hawthorn industry, is rich in potentially health-promoting flavonoids compounds. In this paper, the ultrasound-assisted extraction (UAE) of FC from HS was investigated. Important variables and their levels were obtained using Plackett-Burman (PB) design and Box-Behnken (BB) design. A mathematical model was developed to show the effects of each variable and their combinatorial interactions on extraction yield of FC. A high coefficient of determination (R(2) = 91.26%) indicated good agreement between the experimental and predicted values of FC yield. The optimum levels of these significant parameters were determined using response surface methodology (RSM), which revealed these as follows: ultrasound temperature 65 °C, ultrasonic time 37 min, extraction temperature 91 °C, extraction time 1.5h, solid-liquid ratio of 1:18, and 72% ethanol. Under the optimum condition, the UAE rate of FC was up to 91.7%, and the yield of FC was 16.45 ± 0.02 mg/g (P<0.05) that was 1.32-fold the yield of conventional reflux extraction (CRE).

Correlation between antioxidant activity of garlic extracts and WEHI-164 fibrosarcoma tumor growth in BALB/c mice.

The biological activities of garlic may be affected by different processing methods. This study, therefore, aimed to evaluate potential anticancer effects of different type of processed garlic extracts on WEHI-164 tumor cells in inbred BALB/c mice and correlate the tumor growth rates with some garlic constituents. In a preclinical trial 60 BALB/c mice were injected with WEHI-164 tumor cells and divided into six groups of 10 animals. Group 1 mice received 200 µL of saline, and groups 2-6 were injected intraperitoneally with fresh, microwaved, 3-month-old, leaves, and boiled garlic extracts, respectively, at 20 mg/kg/0.2 mL. Three weeks following tumor inoculation, the mean tumor size in garlic extract-treated groups was reduced with significant reductions observed in the fresh and microwaved extract groups compared with the control group (P<.05). The antioxidant capacity and the amounts of allicin, flavonoids, and phenolic compounds in differentially processed garlic were evaluated and correlated with their anticancer activities. There was a linear correlation between the amounts of allicin, flavonoids, or phenolic components derived from fresh, microwaved, 3-month-old, leaves, and boiled garlic and cancer growth prevention. In conclusion, garlic has anticancer activity against WEHI-164 tumor cells, and processing such as heating reduces its effect dramatically. The anticancer activities of different kinds of garlic are related to the level of allicin, flavonoids, and phenolic components. Therefore, fresh garlic has the highest content of bioactive components and the greatest anticancer efficacy.

[Effects of light on flavonoids accumulation and related gene expression in suspension cultures of Scutellaria baicalensis].

OBJECTIVE: To investigate the effects of light on baicalin,baicalein accumulation and related genes expression in suspension cultures of Scutellaria baicalensis. METHOD: The content of baicalin, baicalein in suspension cultures of S. baicalensis was determined by HPLC. The related genes expression was analyzed by semi-quantitative PCR. RESULT: Active ingredients in suspension cultures of S. baicalensis were promoted significantly by light, PAL gene transcription under the conditions of light was higher than that under the dark conditions, the UBGAT gene expression levels was significantly related to the baicalein (r = -0.995). CONCLUSION: Active ingredients and related genes (PAL, UBGAT) in suspension cultures of S. baicalensis were promoted significantly by light.

The use of a photoactivatable kaempferol analogue to probe the role of flavonol 3-O-galactosyltransferase in pollen germination.

Flavonol induced pollen germination in petunia is rapid, specific, and achieved at low concentrations of kaempferol or quercetin. To determine the macromolecules that interact with the flavonol signal we have synthesized affinity-tagged kaempferol analogues. The first generation molecules are based on a benzophenone photophore. We find that 2-(3-benzoylphenyl)-3,5,7-trihydroxychromen-4-one (BPKae) antagonizes flavonol-induced pollen germination in a concentration-dependent manner. Further, BPKae acts as an irreversible inhibitor of flavonol 3-O-galactosyltransferase (F3GalTase), the gametophyte-specific enzyme that controls the accumulation of glycosylated flavonols in pollen. The effects of BPKae are mediated by UV-A light treatment. The binding characteristics of BPKae to F3GalTase suggest that it can be used to identify the residues required for flavonol-binding and catalysis.