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.

Application of Light-Emitting Diodes for Improving the Nutritional Quality and Bioactive Compound Levels of Some Crops and Medicinal Plants.

Light is a key factor that affects phytochemical synthesis and accumulation in plants. Due to limitations of the environment or cultivated land, there is an urgent need to develop indoor cultivation systems to obtain higher yields with increased phytochemical concentrations using convenient light sources. Light-emitting diodes (LEDs) have several advantages, including consumption of lesser power, longer half-life, higher efficacy, and wider variation in the spectral wavelength than traditional light sources; therefore, these devices are preferred for in vitro culture and indoor plant growth. Moreover, LED irradiation of seedlings enhances plant biomass, nutrient and secondary metabolite levels, and antioxidant properties. Specifically, red and blue LED irradiation exerts strong effects on photosynthesis, stomatal functioning, phototropism, photomorphogenesis, and photosynthetic pigment levels. Additionally, ex vitro plantlet development and acclimatization can be enhanced by regulating the spectral properties of LEDs. Applying an appropriate LED spectral wavelength significantly increases antioxidant enzyme activity in plants, thereby enhancing the cell defense system and providing protection from oxidative damage. Since different plant species respond differently to lighting in the cultivation environment, it is necessary to evaluate specific wavebands before large-scale LED application for controlled in vitro plant growth. This review focuses on the most recent advances and applications of LEDs for in vitro culture organogenesis. The mechanisms underlying the production of different phytochemicals, including phenolics, flavonoids, carotenoids, anthocyanins, and antioxidant enzymes, have also been discussed.

UV-C mediated accumulation of pharmacologically significant phytochemicals under light regimes in in vitro culture of Fagonia indica (L.).

Fagonia indica (L.) is an important medicinal plant with multitude of therapeutic potentials. Such application has been attributed to the presence of various pharmacological important phytochemicals. However, the inadequate biosynthesis of such metabolites in intact plants has hampered scalable production. Thus, herein, we have established an in vitro based elicitation strategy to enhance such metabolites in callus culture of F. indica. Cultures were exposed to various doses of UV radiation (UV-C) and grown in different photoperiod regimes and their impact was evaluated on biomass accumulation, biosynthesis of phytochemicals along antioxidant expression. Cultures grown under photoperiod (16L/8D h) after exposure to UV-C (5.4 kJ/m2) accumulated optimal biomass (438.3 g/L FW; 16.4 g/L DW), phenolics contents (TPC: 11.8 µgGAE/mg) and flavonoids contents (TFC: 4.05 µgQE/mg). Similarly, HPLC quantification revealed that total production (6.967 µg/mg DW) of phytochemicals wherein kaempferol (1.377 µg/mg DW), apigenin (1.057 µg/mg DW), myricetin (1.022 µg/mg DW) and isorhamnetin (1.022 µg/mg DW) were recorded highly accumulated compounds in cultures at UV-C (5.4 kJ/m2) dose than other UV-C radiations and light regimes.. The antioxidants activities examined as DPPH (92.8%), FRAP (182.3 µM TEAC) and ABTS (489.1 µM TEAC) were also recorded highly expressed by cultures under photoperiod after treatment with UV-C dose 5.4 kJ/m2. Moreover, same cultures also expressed maximum % inhibition towards phospholipase A2 (sPLA2: 35.8%), lipoxygenase (15-LOX: 43.3%) and cyclooxygenases (COX-1: 55.3% and COX-2: 39.9%) with 1.0-, 1.3-, 1.3- and 2.8-fold increased levels as compared with control, respectively. Hence, findings suggest that light and UV can synergistically improve the metabolism of F. indica and could be used to produce such valuable metabolites on commercial scale.

Effects of Supplementary Blue and UV-A LED Lights on Morphology and Phytochemicals of Brassicaceae Baby-Leaves.

Brassicaceae baby-leaves are good source of functional phytochemicals. To investigate how Chinese kale and pak-choi baby-leaves in response to different wavebands of blue (430 nm and 465 nm) and UV-A (380 nm and 400 nm) LED, the plant growth, glucosinolates, antioxidants, and minerals were determined. Both agronomy traits and phytochemical contents were significantly affected. Blue and UV-A light played a predominant role in increasing the plant biomass and morphology, as well as the contents of antioxidant compounds (vitamin C, vitamin E, phenolics, and individual flavonols), the antioxidant activity (DPPH and FRAP), and the total glucosinolates accumulation. In particular, four light wavebands significantly decreased the content of progoitrin, while 400 nm UV-A light and 430 nm blue light were efficient in elevating the contents of sinigrin and glucobrassicin in Chinese kale. Meanwhile, 400 nm UV-A light was able to increase the contents of glucoraphanin, sinigrin, and glucobrassicin in pak-choi. From the global view of heatmap, blue lights were more efficient in increasing the yield and phytochemical levels of two baby-leaves.

Gamma irradiation for enhancing active chemical compounds in leaf extracts of Libidibia ferrea (Leguminosae).

This research was designed to evaluate the influence of the irradiation process of the leaf extracts of Libidibia ferrea (Leguminosae) on the production of secondary chemical compounds, including their biological activity. Leaves were collected and prepared to obtain the crude extract, which was then aliquoted and separately exposed to a Co-60 source with different doses, namely: 5, 7, 10, 12, 15, 20, 25, and 30 kGy. From irradiated and control samples, tests of toxicity were carried out with the microcrustacea Artemia salina Leach at three moments: 24 h, 60 and 180 days after the irradiation of the samples. Bioassays showed an increase in the toxicity of the irradiated extracts, correlated with the dose. The toxicity level did not change with the storage time, indicating the excellent stability of the samples. To assess the phytochemical profile of the crude and irradiated extracts, three techniques were employed: thin-layer chromatography (TLC), liquid chromatography coupled to mass spectrometry (LC-MS), and gas chromatography coupled to mass spectrometry (GC-MS). The phytochemical results emphasized the presence of phenols, tannins, and triterpenes. The analytical tests confirmed the role of ionizing radiation in breaking down macromolecules into simpler chemical species responsible for increasing chemical activity of the extract. This report presents and discusses ionizing radiation as an outstanding tool for enhancing active chemical compounds in leaf extracts of Libidibia ferrea, which reflects on their biochemical properties.

Effects of gamma irradiation on the shelf-life and bioactive compounds of Tuber aestivum truffles packaged in passive modified atmosphere.

The effects of gamma irradiation (0.5, 1.0, 1.5 and 2.5 kGy doses) on Tuber aestivum packaged under modified atmosphere was evaluated. The respiration rate, microbial populations, sensory characteristics and content of bioactive compounds (total carbohydrates, chitins, ß-glucans, proteins, total phenols and sterols) were monitored from immediately after treatment up to day 42 of storage at 4 °C. All the irradiation treatments tested reduced the microbial groups studied by more than 3 log cfu/g. Increasing irradiation doses slowed down the subsequent microbial development throughout the conservation period for all the groups studied. The irradiation treatments did not negatively affect truffle sensory characteristics. Only a slight visible superficial yeast growth was detected at the end of the shelf-life in all doses applied. Total carbohydrate content, chitins, ß-glucans and proteins levels were not affected after irradiation. However, sterols, particularly stigmasterol, slightly decreased after irradiation, while levels of phenolic compounds doubled during storage. Gamma irradiation (2.5 kGy) could be used to extend the shelf-life of summer truffles packaged under modified atmosphere, since no remarkable reduction of bioactive compounds were noticed after 42 days of storage, and their sensory and microbial parameters were of higher quality than those of non-irradiated controls.

LED-enhanced biosynthesis of biologically active ingredients in callus cultures of Ocimum basilicum.

Ocimum basilicum is a medicinal plant with multiple health benefits including cardiovascular, cancer and diabetics. In the present study, the influences of light emitting diodes (LEDs) were investigated on the accumulation of biologically active ingredients in callus cultures of Ocimum basilicum. Among the various tested treatments optimum levels of Total phenolic content (TPC) was noted in callus culture grown under blue lights as compared to control, while maximum accumulation of Total flavonoid content (TFC) was noted in callus culture grown under red light as compared to control. HPLC analyses showed that highest concentrations of Rosmarinic acid (96.0 mg/g DW) and Eugenol (0.273 mg/g DW) were accumulated in blue light which was 2.46 and 2.25 times greater than control (39.0 mg/g DW, 0.171 mg/g DW), respectively. Chicoric acid (81.40 mg/g DW) optimum accumulation was noted in callus grown under the continuous white light, which was almost 4.52 times greater than control. Anthocyanins content were also analyzed, the highest amount of Peonidin (0.127 mg/g DW) and cyanidin (0.1216 mg/g DW) were found in callus culture grown under red light. These findings suggest that application of LED's is a promising strategy for enhancing production of biologically active ingredients in callus cultures Ocimum basilicum.

Effect of Ionizing Radiation on the Microbiological Safety and Phytochemical Properties of Cooked Malva sylvestris L.

Nowadays, recent studies have demonstrated that plant-derived foods were characterized by their richness in bioactive phytochemicals and their consumption has a protective effect for human health. The effects of ionizing radiation on phytochemical properties of cooked Malva sylvestris L. (Mallow) were investigated. Irradiation increased significantly (P<0.05) the total polyphenols and flavonoids content of cooked Mallow. Irradiation at 2 and 4 kGy doses resulted in a significant increase in the DPPH and ABTS radical-scavenging ability of cooked Mallow extracts. There was no significant change on carbohydrate, lipid, ash, and protein content. While the mineral composition of K and Na was affected slightly after irradiation, the amounts of Mg, P, Ca, Fe, Z, and Cu remain unaffected at 2 kGy and reduced slightly at 4 kGy. The antimicrobial activity was unaffected after irradiation. Postirradiation storage studies showed that the cooked irradiated Mallow was microbiologically safe even after 20 days of storage period. Sensory properties of cooked irradiated Mallow were unaffected by the treatment. This study supports that cooking process followed by gamma irradiation did not compromise the chemical composition and sensory characteristics of Mallow.

Euphorbia kansui fry-baked with vinegar modulates gut microbiota and reduces intestinal toxicity in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Euphorbia kansui (EK), a kind of toxic traditional Chinese medicine (TCM), is used in the treatment of edema, ascites and asthma. EK fry-baked with vinegar (VEK) is regularly used to reduce the toxicity in TCM. Previous studies have confirmed that fry-baking with vinegar could significantly reduce the significant gastrointestinal toxicity of EK. The toxic side-effects of EK are closely associated with intestinal tract, but existing research results could not provide practical measures for detoxification in terms of the biological effects of EK fry-baked with vinegar. AIM OF THE STUDY: This study aimed to investigate the gastrointestinal toxicity of EK and detoxification of VEK through the regulation of gut microbiota. Thirty male Sprague Dawley (SD) rats were randomly divided equally into 3 groups and received by oral gavage 0.5% CMC-Na (C group), EK (EKC group) or VEK (VEKC group) powder at 680 mg/kg for seven consecutive days. RESULTS: The ten toxic components in VEK were reduced significantly compared with those in EK. After fry-baked with vinegar, those side effects associated with VEK were significantly relieved in terms of histopathology and inflammatory injury indices of intestinal tissues, liver function and oxidative damage indices. The toxicity of EK might be highly correlated with Lactobacillus and Blautia genera. In addition, EK fry-baked with vinegar increased the production of short-chain fatty acids (SCFAs), which are regulated by gut microbiota. CONCLUSIONS: The proportion of main probiotics increased and potentially pathogenic bacteria decreased after EK was fry-baked with vinegar. It turned out that effective detoxification could be achieved by fry-baking with vinegar.

Photooxidation of phytochemicals in food and control: a review.

Phytochemicals are widely present in food and have been confirmed to be bioactive, thereby contributing to human health. However, some phytochemicals are sensitive to light owing to their structures and may suffer from photodegradation, especially when sensitizers exist, resulting in sensory quality change, nutrient loss in food, and even the formation of toxic compounds. The photooxidation of phytochemicals occurs through three different mechanisms: (1) by directly absorbing luminous energy, (2) with triplet-excited state sensitizers through electron transfer or proton transfer (type I photooxidation), and (3) with singlet oxygen produced by O2 (type II photooxidation). On the basis of these mechanisms, adequate antioxidants can be added to quench the triple-excited state sensitizers or singlet oxygen to protect against the photooxidation of phytochemicals in food. Here, we summarize and discuss the possible pathways and products of the photooxidation of phytochemicals that have been reported and the relationships between structures and photooxidation. We also propose some control measures, with special attention paid to the potential abilities of phytochemicals in the prevention of food photooxidation.