Blue LED light promoting the growth, accumulation of high-value isoflavonoids and astragalosides, antioxidant response, and biosynthesis gene expression in Astragalus membranaceus (Fisch.) Bunge hairy root cultures.

The root of Astragalus membranaceus (Fisch.) Bunge is one of the most frequently used herbs in traditional Chinese medicine (TCM) formulae for fighting COVID-19 infections, due to the presence of isoflavonoids and astragalosides associated with antiviral and immune-enhancing activities. For the first time, the exposure of A. membranaceus hairy root cultures (AMHRCs) to different colors of LED lights i.e., red, green, blue, red/green/blue (1/1/1, RGB), and white, was conducted to promote the root growth and accumulation of isoflavonoids and astragalosides. LED light treatment regardless of colors was found beneficial for root growth, which might be a result of the formation of more root hairs upon light stimulation. Blue LED light was found most effective for enhancing phytochemical accumulation. Results showed that the productivity of root biomass in blue-light grown AMHRCs with an initial inoculum size of 0.6% for 55 days was 1.40-fold higher than that in dark (control), and yields of high-value isoflavonoids and astragalosides including calycosin, formononetin, astragaloside IV, and astragaloside I increased by 3.17-fold, 2.66-fold, 1.78-fold, and 1.52-fold relative to control, respectively. Moreover, the photooxidative stress together with transcriptional activation of biosynthesis genes might contribute to the enhanced accumulation of isoflavonoids and astragalosides in blue-light grown AMHRCs. Overall, this work offered a feasible approach for obtaining higher yields of root biomass and medicinally important compounds in AMHRCs via the simple supplementation of blue LED light, which made blue-light grown AMHRCs industrially attractive as plant factory in controlled growing systems. Supplementary Information: The online version contains supplementary material available at 10.1007/s11240-023-02486-7.

Health-Promoting Phenolic Compound Accumulation, Antioxidant Response, Endogenous Salicylic Acid Generation, and Biosynthesis Gene Expression in Germinated Pigeon Pea Seeds Treated with UV-B Radiation.

Germinated pigeon pea seeds (GPPSs) are good dietary supplements with satisfactory nutritional and medicinal values. In this study, UV-B treatment was used to promote the accumulation of health-promoting phenolic compounds (10 flavonoids and 1 stilbene) in GPPS. The total yield of 11 phenolic compounds (235 839.76 ± 17 118.24 ng/g DW) significantly improved (2.53-fold increase) in GPPSs exposed to UV-B radiation (3 W/m2) for 8 h, whereas free amino acid and reducing sugar contents exhibited a decreasing tendency during UV-B exposure. Meanwhile, the positive response in the antioxidant activities of enzymes and nonenzymatic extracts was noticed in UV-B-treated GPPSs. Moreover, UV-B radiation could cause tissue damages in hypocotyls and cotyledons of the GPPSs and enhance the generation of endogenous salicylic acid, thus activating the expression of biosynthesis genes (especially CHS and STS1). Overall, the simple UV-B supplementation strategy makes GPPSs more attractive as functional foods/nutraceuticals in diet for promoting human health.

Simultaneous quantification of eleven bioactive phenolic compounds in pigeon pea natural resources and in vitro cultures by ultra-high performance liquid chromatography coupled with triple quadrupole mass spectrometry (UPLC-QqQ-MS/MS).

Bioactive phenolics primarily contribute to versatile health benefits of pigeon pea. For the first time, an UPLC-QqQ-MS/MS method was developed for the quantitative analysis of eleven bioactive phenolic compounds in pigeon pea natural resources (seeds, leaves, and roots) and in vitro cultures (calli and hairy roots). The proposed method could be achieved within 6 min of running time, and displayed the satisfactory linearity, sensitivity, precision, accuracy, and stability. According to analytical results, the distribution of eleven target compounds in different organs of pigeon pea was clarified. Also, it was surprisingly found that pigeon pea in vitro cultures exhibited superiority in contents of genistin and cajaninstilbene acid as compared with natural resources. Overall, the present work provided a rapid and sensitive analysis approach, which could be useful not only for quality control of pigeon pea natural resources, but also for applicability and safety evaluation of pigeon pea in vitro cultures.

Effective Production of Phenolic Compounds with Health Benefits in Pigeon Pea [Cajanus cajan (L.) Millsp.] Hairy Root Cultures.

Phenolic compounds in pigeon pea possess various biological properties beneficial to human health. In this study, pigeon pea hairy root cultures (PPHRCs) were developed as an effective in vitro platform for the production of phenolic compounds. A high-productive hairy root line was screened and characterized, and its culture conditions were optimized in terms of biomass productivity and phenolic yield. The comparative profiling of 10 phenolic compounds in PPHRCs and pigeon pea natural resources (seeds, leaves, and roots) was achieved by ultra-high-performance liquid chromatography-tandem mass spectrometry analysis. The total phenolic yield in PPHRCs (3278.44 µg/g) was much higher than those in seeds (68.86 µg/g) and roots (846.03 µg/g), and comparable to leaves (3379.49 µg/g). Notably, PPHRCs exhibited superiority in the yield of the most important health-promoting compound cajaninstilbene acid (2996.23 µg/g) against natural resources (4.42-2293.31 µg/g). Overall, PPHRCs could serve as promising potential alternative sources for the production of phenolic compounds with nutraceutical/medicinal values.

Enhanced Production of Two Bioactive Isoflavone Aglycones in Astragalus membranaceus Hairy Root Cultures by Combining Deglycosylation and Elicitation of Immobilized Edible Aspergillus niger.

A cocultivation system of Astragalus membranaceus hairy root cultures (AMHRCs) and immobilized food-grade fungi was established for the enhanced production of calycosin (CA) and formononetin (FO). The highest accumulations of CA (730.88 ± 63.72 µg/g DW) and FO (1119.42 ± 95.85 µg/g DW) were achieved in 34 day-old AMHRCs cocultured with immobilized A. niger (IAN) for 54 h, which were 7.72- and 18.78-fold higher than CA and FO in nontreated control, respectively. IAN deglycosylation could promote the formation of CA and FO by conversion of their glycoside precursors. IAN elicitation could intensify the generation of endogenous signal molecules involved in plant defense response, which contributed to the significantly up-regulated expression of genes in CA and FO biosynthetic pathway. Overall, the coupled culture of IAN and AMHRCs offered a promising and effective in vitro approach to enhance the production of two health-promoting isoflavone aglycones for possible nutraceutical and pharmaceutical uses.

Enhanced and green extraction polyphenols and furanocoumarins from Fig (Ficus carica L.) leaves using deep eutectic solvents.

Nowadays, green extraction of bioactive compounds from medicinal plants has gained increasing attention. As green solvent, deep eutectic solvent (DES) have been highly rated to replace toxic organic solvents in extraction process. In present study, to simultaneous extraction five main bioactive compounds from fig leaves, DES was tailor-made. The tailor-made DES composed of a 3:3:3 molar ratio of glycerol, xylitol and D-(-)-Fructose showed enhanced extraction yields for five target compounds simultaneously compared with traditional methanol and non-tailor DESs. Then, the tailor-made DES based extraction methods have compared and microwave-assisted extraction was selected and optimized due to its high extraction yields with lower time consumption. The influencing parameters including extraction temperature, liquid-solid ratio, and extraction time were optimized using response surface methodology (RSM). Under optimal conditions the extraction yield of caffeoylmalic acid, psoralic acid-glucoside, rutin, psoralen and bergapten was 6.482mg/g, 16.34mg/g, 5.207mg/g, 15.22mg/g and 2.475mg/g, respectively. Macroporous resin D101 has been used to recovery target compounds with recovery yields of 79.2%, 83.4%, 85.5%, 81.2% and 75.3% for caffeoylmalic acid, psoralic acid-glucoside, rutin, psoralen and bergapten, respectively. The present study suggests that DESs are truly designer and efficient solvents and the method we developed was efficient and sustainable for extraction main compounds from Fig leaves.mg/g.

Antioxidant Properties of Phenolic Compounds in Renewable Parts of Crataegus pinnatifida inferred from Seasonal Variations.

In this study, the effect of seasonal variations on Crataegus pinnatifida, changes in antioxidant activity and active components in C. pinnatifida leaves, roots, twigs, and fruits from May to October were investigated. Through correlation analysis of climatic factors and 7 phenolic compounds yield, the phenolic compounds content was positively correlated with temperatures and daytime. The correlation coefficient of temperatures and daytime were 0.912 and 0.829, respectively. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, 2,2'-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging and reducing power tests were employed to evaluate the antioxidant activity of the C. pinnatifida. C. pinnatifida leaves exhibited significant advantages in terms of higher phenolic contents and excellent antioxidant activities. Principal component analysis (PCA) revealed that 2 main PC characterize the C. pinnatifida phenolic composition (82.1% of all variance). C. pinnatifida leaves in September possessed remarkable antioxidant activity. The results elucidate that C. pinnatifida leaves, as renewable parts, are suitable for application as antioxidant ingredients.

Efficient production of isoflavonoids by Astragalus membranaceus hairy root cultures and evaluation of antioxidant activities of extracts.

In this study, Astragalus membranaceus hairy root cultures (AMHRCs) were established as an attractive alternative source for the efficient production of isoflavonoids (IF). A. membranaceus hairy root line II was screened as the most efficient line and was confirmed by PCR amplification of rolB, rolC and aux1 genes. Culture parameters of AMHRCs were systematically optimized, and five main IF constituents were quali-quantitatively determined by LC-MS/MS. Under optimal conditions, the total IF accumulation of 34 day old AMHRCs was 234.77 µg/g dry weight (DW). This yield was significantly higher compared to that of 3 year old field grown roots (187.38 µg/g DW). Additionally, in vitro antioxidant assays demonstrated that AMHRC extracts exhibited antioxidant activities with lower IC50 values (1.40 and 1.73 mg/mL) as compared to those of field grown roots (1.96 and 2.17 mg/mL). Overall, AMHRCs may offer a promising and continuous product platform for naturally derived, high quality and valuable nutraceuticals.

Microwave-assisted aqueous enzymatic extraction of oil from pumpkin seeds and evaluation of its physicochemical properties, fatty acid compositions and antioxidant activities.

Microwave-assisted aqueous enzymatic extraction (MAAEE) of pumpkin seed oil was performed in this study. An enzyme cocktail comprised of cellulase, pectinase and proteinase (w/w/w) was found to be the most effective in releasing oils. The highest oil recovery of 64.17% was achieved under optimal conditions of enzyme concentration (1.4%, w/w), temperature (44°C), time (66 min) and irradiation power (419W). Moreover, there were no significant variations in physicochemical properties of MAAEE-extracted oil (MAAEEO) and Soxhlet-extracted oil (SEO), but MAAEEO exhibited better oxidation stability. Additionally, MAAEEO had a higher content of linoleic acid (57.33%) than SEO (53.72%), and it showed stronger antioxidant activities with the IC50 values 123.93 and 152.84, mg/mL, according to DPPH radical scavenging assay and ß-carotene/linoleic acid bleaching test. SEM results illustrated the destruction of cell walls and membranes by MAAEE. MAAEE is, therefore, a promising and environmental-friendly technique for oil extraction in the food industry.

Rapid analysis of Fructus forsythiae essential oil by ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction followed by gas chromatography-mass spectrometry.

A rapid, green and effective miniaturized sample preparation and analytical technique, i.e. ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction (ILAMD-HS-SDME) followed by gas chromatography-mass spectrometry (GC-MS) was developed for the analysis of essential oil (EO) in Fructus forsythiae. In this work, ionic liquids (ILs) were not only used as the absorption medium of microwave irradiation but also as the destruction agent of plant cell walls. 1-Ethyl-3-methylimidazolium acetate ([C2mim]OAc) was chosen as the optimal ILs. Moreover, n-heptadecane (2.0 µL) was selected as the appropriate suspended solvent for the extraction and concentration of EO. Extraction conditions of the proposed method were optimized using the relative peak area of EO constituents as the index, and the optimal operational parameters were obtained as follows: irradiation power (300 W), sample mass (0.7 g), mass ratio of ILs to sample (2.4), temperature (78°C) and time (3.4 min). In comparison to previous reports, the proposed method was faster and required smaller sample amount but could equally monitor all EO constituents with no significant differences.

Biodiesel from Forsythia suspense [(Thunb.) Vahl (Oleaceae)] seed oil.

In the present work, Forsythia suspense seed oil (FSSO) was investigated for the first time as an alternative non-conventional feedstock for the preparation of biodiesel. The FSSO yield is 30.08±2.35% (dry weight of F. suspense seed basis), and the oil has low acid value (1.07 mg KOH/g). The fatty acid composition of FSSO exhibits the predominance of linoleic acid (72.89%) along with oleic acid (18.68%) and palmitic acid (5.65%), which is quite similar to that of sunflower oil. Moreover, microwave-assisted transesterification process of FSSO with methanol in the presence of potassium hydroxide catalyst was optimized and an optimal biodiesel yield (90.74±2.02%) was obtained. Furthermore, the fuel properties of the biodiesel product were evaluated as against ASTM D-6751 biodiesel standards and an acceptable agreement was observed except the cetane number. Overall, this study revealed the possibility of FSSO as a potential resource of biodiesel feedstock.