Phenolic Profiles and Antioxidant Activity of Lotus Root Varieties

Ultrasound-assisted extraction of polyphenols from lotus rhizome epidermis by alcohol/salt-based aqueous two-phase system: Optimization, extraction mechanism and antioxidant activities

In this study, ultrasonic-assisted (UA) alcohol/salt-based aqueous two-phase system (ATPS) method was constructed to extract lotus rhizome epidermis (LRE) polyphenols. The extraction conditions were optimized as salt concentration 26.75 %, ethanol concentration 25.45 %, ultrasonic power 487 W and liquid-solid ratio 35.33 mL/g by comparing response surface methodology (RSM) and artificial neural network (ANN) models. Then, l-dopa (2.35 ± 0.036 mg/g dw), gallocatechin (1.66 ± 0.0035 mg/g dw) and epigallocatechin (1.37 ± 0.0035 mg/g dw) were determined as major polyphenols in LRE by using UA-ATPS method. Moreover, study showed that ultrasound, van der Waals force, hydrogen bond and salting out could accelerate the mass transfer and extraction of polyphenols in LRE cells. The high-pressure cavity and collapse effect of ultrasound could also accelerate the extraction of polyphenols. In vitro antioxidant experiments showed that LRE polyphenols have good antioxidant ability. In sum, this study developed a green and efficient extraction method to enhance the profitability of LRE in food and medicine industries.

Formation mechanism of blue pigment in boiled lotus rhizome discs: Insight into the chelation of polyphenols and iron

Boiled lotus rhizome discs (BLRDs), as common processed products of lotus rhizome, have gained increasing attention from consumers and food manufacturers. However, the blue pigment formed during boiling affects its appearance and reduces the appetite of BLRDs. In this study, the effects of polyphenols and iron contents on blue pigment formation in BLRDs in different regions and months were investigated. Results revealed that blue variation was more serious in March and April of the second year in Wuhan, and polyphenols and iron contents in these two months were significantly higher than those in other months. Then, UPLC and UV-Vis analysis showed that polyphenols causing the formation of blue pigment in BLRDs were L-dopa, gallocatechin, catechin, epigallocatechin, chlorogenic acid and epicatechin, among which L-dopa (52.450 mg/100 g in fresh lotus rhizome (FLR)) and gallocatechin (36.210 mg/100 g in FLR) possessed the greatest effect. Moreover, the ESI-Q-TOF-MS analysis of L-dopa-iron chelate and gallocatechin-iron chelate suggested that the blue pigment of BLRDs was mainly in the form of bis-complexes under boiling conditions. The study on formation mechanism of blue pigment in BLRDs can provide a reference for lotus rhizome processing.

Cost-effective and natural-inspired lotus root/GelMA scaffolds enhanced wound healing via ROS scavenging, angiogenesis and reepithelialization

Skin wounds, prevalent and fraught with complications, significantly impact individuals and society. Wound healing encounters numerous obstacles, such as excessive reactive oxygen species (ROS) production and impaired angiogenesis, thus promoting the development of chronic wound. Traditional clinical interventions like hemostasis, debridement, and surgery face considerable challenges, including the risk of secondary infections. While therapies designed to scavenge excess ROS and enhance proangiogenic properties have shown effectiveness in wound healing, their clinical adoption is hindered by high costs, complex manufacturing processes, and the potential for allergic reactions. Lotus root, distinguished by its natural micro and macro porous architecture, exhibits significant promise as a tissue engineering scaffold. This study introduced a novel scaffold based on hybridization of lotus root-inspired and Gelatin Methacryloyl (GelMA), verified with satisfactory physicochemical properties, biocompatibility, antioxidative capabilities and proangiogenic abilities. In vivo tests employing a full-thickness wound model revealed that these scaffolds notably enhanced micro vessel formation and collagen remodeling within the wound bed, thus accelerating the healing process. Given the straightforward accessibility of lotus roots and the cost-effective production of the scaffolds, the novel scaffolds with ROS scavenging, pro-angiogenesis and re-epithelialization abilities are anticipated to have clinical applicability for various chronic wounds.

Evaluation of Pre-Harvest Nutrient Composition and Functional Active Substances in Various Lotus Roots

This study investigated the impact of variety and harvest time on the visual appearance, nutritional quality, and functional active substances of six lotus root cultivars: "Xinsanwu", "Wuzhi No. 2", "Baiyuzhan", "Huaqilian", "Elian No. 6", and "Elian No. 5". Samples were collected monthly from December 2023 to April 2024. A nutrient analysis revealed a decrease in the water content with a delayed harvest. The total soluble solids and soluble sugar content peaked towards the end and middle-to-late harvest periods, respectively. Starch levels initially increased before declining, while the soluble protein exhibited a triphasic trend with an initial rise, a dip, and a final increase. The vitamin C (Vc) content varied across cultivars. Functional active substances displayed dynamic changes. The total phenolics initially decreased, then increased, before ultimately declining again. The total flavonoid content varied by both cultivar and harvest time. The phenolic acid and flavonoid content mirrored the trends observed for total phenolics and total flavonoids. Gastrodin was the most abundant non-flavonoid compound across all varieties. "Wuzhi No. 2" and "Baiyuzhan" displayed higher levels of functional active substances and starch, while the Elian series and "Xinsanwu" cultivar exhibited a greater content of Vc, soluble sugar, and soluble protein. Specific harvest periods yielded optimal results: "Wuzhi No. 2" (H1 and H5), "Huaqilian" (H2), and "Baiyuzhan" (H3 and H4) demonstrated a high nutrient and functional active substance content. Overall, the lotus roots harvested in period H4 achieved the highest score. Overall, this study provides the foothold for the rapid identification of superior lotus root cultivars and the valorization of lotus root by-products via advanced processing methods. Additionally, it offers valuable insights for market participants and consumers to select optimal varieties and harvest times based on their specific needs.

Study on the formation mechanism of blackening in damaged lotus rhizome epidermis: Effects of polyphenols and iron

Lotus rhizome is an important aquatic vegetable, but the blackening of lotus rhizome epidermis (LRE) seriously affects its appearance and quality, which makes lotus rhizome products unmarketable. In this study, the effects of polyphenols and iron on the LRE color were studied to explore the possible mechanism of LRE blackening. Results indicated that the measurable total phenols contents in the mud treatment (MT) group were significantly reduced, and the total iron contents were significantly increased compared with the bruised treatment group (p < 0.05). The high-performance liquid chromatography results showed that the main polyphenols in LRE were dopa, gallocatechin, and catechin, as well as a small amount of catechol, epicatechin, proanthocyanidin B2, and proanthocyanidin C1. Moreover, the results of color difference and ultraviolet adsorption spectroscopy showed that there were obviously black or brown-gray of dopa (525 nm), gallocatechin (504.5 nm), and catechin (550 and 504.5 nm) with FeCl2. The simulated system treatment of LRE further confirmed that the chromaticity effect of dopa and iron in bruised LRE was similar to that of the MT group, whereas 1% (w/w) ascorbic acid, 2% (w/w) EDTA-2Na, or 3% (w/w) citric acid could solely prohibit the blackening. This suggested that the dopa in LRE and FeCl2 in mud may mainly combine into [2(DOPA-2H+)+Fe3+]- through non-covalent interaction, which leads to the blackening of bruised LRE under neutral conditions. These results can guide the storage of lotus rhizomes and improve the development of the lotus rhizome industry.

Complexes of Soluble Dietary Fiber and Polyphenols from Lotus Root Regulate High-Fat Diet-Induced Hyperlipidemia in Mice

In this paper, complexes of soluble dietary fiber (SDF) and polyphenols (PPs) isolated from lotus roots were prepared (SDF-PPs), as well as physical mixtures (SDF&PPs), which were given to high-fat-diet (HFD)-fed mice. The results demonstrated that SDF-PPs improve lipid levels and reverse liver injury in hyperlipidemic mice. Western blotting and real-time quantitative Polymerase Chain Reaction (RT-qPCR) results showed that SDF-PPs regulated liver lipids by increasing the phosphorylation of Adenine monophosphate activated protein kinase (AMPK), up-regulating the expression of Carnitine palmitoyltransferase1 (CPT1), and down-regulating the expression of Fatty acid synthase (FAS) and 3-hydroxy-3-methyl glutaryl coenzyme A (HMG-CoA), as well as the transcription factor sterol-regulatory element binding protein (SPEBP-1) and its downstream liposynthesis genes. Additionally, the intervention of SDF-PPs could modulate the composition of intestinal gut microbes, inducing an increase in Lachnospiraceae and a decrease in Desulfovibrionaceae and Prevotellaceae in high-fat-diet-fed mice. Thus, the research provides a theoretical basis for the application of lotus root active ingredients in functional foods and ingredients.

Persistent effects of swine manure biochar and biogas slurry application on soil nitrogen content and quality of lotus root

Using swine manure biochar and biogas slurry in agriculture proves to be an effective strategy for soil improvement and fertilization. In this study, a pot trial on the growth of lotus root was conducted to investigate the persistent effects of applying 350°C swine manure biochar (1% and 2%) and biogas slurry (50% and 100%) on soil nitrogen nutrient and lotus root quality. The results showed that compared to chemical fertilizer alone (A0B0), swine manure biochar significantly increased soil nitrogen content after one year of application. The contents of total nitrogen (TN), alkali-hydrolyzed nitrogen (AHN), ammonium nitrogen (NH4 +-N), and nitrate nitrogen (N O 3 -   - N ) increased by 17.96% to 20.73%, 14.05% to 64.71%, 17.76% to 48.68% and 2.22% to 8.47%, respectively, during the rooting period. When swine manure biochar was present, the application of biogas slurry further elevated soil nitrogen content. The co-application of swine manure biochar and biogas slurry significantly increased soil nitrogen content, and the 100% nitrogen replacement with biogas slurry combined with 2% swine manure biochar (A2B2) treatment exhibited the most significant enhancement effect during whole plant growth periods. Soil enzyme activities, including soil protease (NPT), leucine aminopeptidase (LAP), b-glucosidase (β-GC) and dehydrogenase (DHA), showed a tendency to increase and then decrease with the prolongation of lotus root fertility period, reaching the maximum value during the rooting period. Compared to A0B0, the treatment with 2% swine manure biochar had the most significant effect on enzyme activities and increased the lotus root's protein, soluble sugar, and starch contents. Nitrate content decreased with the application of 2% swine manure biochar as the amount of biogas slurry increased. In conclusion, swine manure biochar effectively improved soil nitrogen content, enzyme activity, and lotus root quality. Even after one year of application, 2% swine manure biochar had the best enhancement effect.

Physicochemical and Functional Changes in Lotus Root Polysaccharide Associated with Noncovalent Binding of Polyphenols

To promote the functional applications of lotus root polysaccharides (LRPs), the effects of noncovalent polyphenol binding on their physicochemical properties, as well as antioxidant and immunomodulatory activities, were investigated. Ferulic acid (FA) and chlorogenic acid (CHA) were spontaneously bound to the LRP to prepare the complexes LRP-FA₁, LRP-FA₂, LRP-FA₃, LRP-CHA₁, LRP-CHA₂ and LRP-CHA₃, and their mass ratios of polyphenol to LRP were, respectively, 121.57, 61.18, 34.79, 2359.58, 1276.71 and 545.08 mg/g. Using the physical mixture of the LRP and polyphenols as a control, the noncovalent interaction between them in the complexes was confirmed by ultraviolet and Fourier-transform infrared spectroscopy. The interaction increased their average molecular weights by 1.11~2.27 times compared to the LRP. The polyphenols enhanced the antioxidant capacity and macrophage-stimulating activity of the LRP depending on their binding amount. Particularly, the DPPH radical scavenging activity and FRAP antioxidant ability were positively related to the FA binding amount but negatively related to the CHA binding amount. The NO production of the macrophages stimulated by the LRP was inhibited by the co-incubation with free polyphenols; however, the inhibition was eliminated by the noncovalent binding. The complexes could stimulate the NO production and tumor necrosis factor-α secretion more effectively than the LRP. The noncovalent binding of polyphenols may be an innovative strategy for the structural and functional modification of natural polysaccharides.

Lotus Root Polysaccharide-Phenol Complexes: Interaction, Structure, Antioxidant, and Anti-Inflammatory Activities

This research aimed to explore the interaction between lotus root polysaccharides (LRPs) and phenolic compounds, and to study the effects of phenolic binding on the structural and functional properties of LRPs. The influences of pH, temperature, and NaCl and phenol concentration on the binding ratio of gallic acid (GA)/epigallocatechin (EGC) to LRPs were evaluated. LRP-GA/EGC complexes with different phenolic binding amounts were then prepared and characterized via ultraviolet-visible (UV-Vis) and Fourier-transform infrared (FTIR) spectroscopy, and average molecular weight (MW) measurements. The results suggest that hydrogen bonds contributed to the binding of GA/EGC and LRPs. The phenolic binding led to significant changes in the structure and MW of LRPs. Moreover, antioxidant activity and the macrophage-stimulating effect of LRPs were improved after binding with GA/EGC, depending on the binding amount and type of polyphenol. Interestingly, LRP-GA/EGC complexes with polyphenol binding amounts of 105.4 mg/g and 50.71 mg/g, respectively, showed better stimulation effects on the anti-inflammatory cytokine IL10 secretion of macrophages when compared to LRPs. These results show the great potential of phenolic binding to be applied to improve the structure and functional activity of LRPs.

Nontarget Metabolites of Rhizomes of Edible Sacred Lotus Provide New Insights into Rhizome Browning

The “edible rhizome” variant of Nelumbo nucifera with various cultivars has a long history of use as a food in East Asia. In this study, 48 target metabolites were untargeted and identified in 212 rhizome cultivars (tropical and temperate types) using ultraperformance liquid chromatography-electrospray ionization quadrupole time-of-flight high-resolution mass spectrometry; among these, 32 compounds were newly reported in the rhizome. Combined with the browning phenotype of 212 lotus rhizomes, (epi) catechin, norarmepavine, and N-feruloyl-3-methoxytyramine were used as predominant chemical markers to separate different degrees of lotus rhizome browning. p-Coumaroyltyramine and N-trans-feruloyltyramine were selected as predominant chemical markers to investigate the differential expression between tropical and temperate lotus using principal component analysis and orthogonal partial least squares discriminant analysis. Shared and unique structure plots were used to compare the outcomes of the ecotype and browning OPLS model, showing that variation in tropical lotus rhizome browning is not obvious; this will be of great importance for genetic improvement by providing a hereditary basis.

A comparative review on the anti-nutritional factors of herbal tea concoctions and their reduction strategies

Tea is an important beverage consumed worldwide. Of the different types of tea available, herbal tea is an important beverage consumed owing to its popularity as a drink and stress relieving factors, several different herbal concoctions made from seeds, leaves, or roots are currently consumed and sold as herbal teas. The herbal teas are not the usual tea but "tisanes." They are caffeine free and popular for their medicinal property or immune boosters. Herbal tea formulations are popularly sold and consumed by millions owing to their health benefits as they are rich in antioxidants and minerals. However, plants are also known to contain toxic and anti-nutritional factors. Anti-nutritional factors are known to interfere with the metabolic process and hamper the absorption of important nutrients in the body. These anti-nutritional factors include saponins, tannins, alkaloids, oxalates, lectins, goitrogens, cyanogens, and lethogens. These chemicals are known to have deleterious effects on human health. Therefore, it is important to understand and assess the merits and demerits before consumption. Also, several techniques are currently used to process and reduce the anti-nutrients in foods. This review is focused on comparing the contents of various anti-nutritional factors in some underutilized plants of North-East India used as herbal tea along with processing methods that can be used to reduce the level of these anti-nutrients.

LC-ESI-QTOF-MS/MS Characterization and Estimation of the Antioxidant Potential of Phenolic Compounds from Different Parts of the Lotus (Nelumbo nucifera) Seed and Rhizome

Edible lotus (Nelumbo nucifera G.) is widely consumed in Asian countries and treated as a functional food and traditional medicinal herb due to its abundant bioactive compounds. Lotus rhizome peels, rhizome knots, and seed embryos are important byproducts and processing waste of edible lotus (Nelumbo nucifera G.) with commercial significance. Nevertheless, the comprehensive phenolic profiling of different parts of lotus is still scarce. Thus, this study aimed to review the phenolic contents and antioxidant potential in lotus seeds (embryo and cotyledon) and rhizomes (peel, knot, and pulp) grown in Australia. In the phenolic content and antioxidant potential estimation assays by comparing to the corresponding reference standards, the lotus seed embryo exhibited the highest total phenolic content (10.77 ± 0.66 mg GAE/g_f.w.), total flavonoid content (1.61 ± 0.03 mg QE/g_f.w.), 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity (9.66 ± 0.10 mg AAE/g_f.w.), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) scavenging activity (14.35 ± 0.20 mg AAE/g_f.w.), and total antioxidant capacity (6.46 ± 0.30 mg AAE/g), while the highest value of ferric ion reducing antioxidant power (FRAP) activity and total tannin content was present in the lotus rhizome knot (2.30 ± 0.13 mg AAE/g_f.w.). A total of 86 phenolic compounds were identified in five parts of lotus by liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS), including phenolic acids (20), flavonoids (51), lignans (3), stilbenes (2), and other polyphenols (10). The most phenolic compounds, reaching up to 68%, were present in the lotus seed embryo (59). Furthermore, the lotus rhizome peel and lotus seed embryo exhibit significantly higher contents of selected polyphenols than other lotus parts according to high-performance liquid chromatography (HPLC) quantification analysis. The results highlighted that byproducts and processing waste of edible lotus are rich sources of phenolic compounds, which may be good candidates for further exploitation and utilization in food, animal feeding, and pharmaceutical industries.

Phenolic profiles, antioxidant activity and inhibition of digestive enzymes of water caltrop pericarps

BACKGROUND

Water caltrop (Trapa natans L.) is widely cultivated as a popular vegetable or fruit in Asian countries. In China, water caltrop pericarp is also used as a functional food to treat metabolic syndrome. However, the profiling of bioactive substances and their pharmacological activities in different water caltrop varieties remains to be investigated. In the present study, three varieties of water caltrop pericarps collected from 13 origins in China were analyzed for their phenolic substances. To investigate the pharmacological activities, samples were tested for their free radical scavenging capacity and inhibitory potency against α-glucosidase and pancreatic lipase.

RESULTS

In total, 46 phenolic compounds were identified in the ethanol extract of water caltrop pericarp using a liquid chromatography-quadrupole time of flight-tandem mass spectrometry method, most of which were hydrolyzable tannins. Two cultivated varieties samples exhibited a relatively higher phenolic content and stronger antioxidant and inhibitory activities against α-glucosidase and pancreatic lipase compared to those from the wild variety. Correlation analysis between phenolic contents and biological activities suggested that phenolic compounds exhibited potential free radical scavenging capacity, α-glucosidase and pancreatic lipase inhibitory activities.

CONCLUSION

It is concluded that the phenolic compounds of water caltrop pericarp are promising sources of natural antioxidants, α-glucosidase and pancreatic lipase inhibitors. © 2021 Society of Chemical Industry.

The mechanism of interaction between lotus rhizome polyphenol oxidase and ascorbic acid: Inhibitory activity, thermodynamics, and conformation analysis

In this study, the interaction between lotus rhizome polyphenol oxidase (PPO) and ascorbic acid (AA) was discussed from the aspects of inhibitory activity, thermodynamics, and conformation. Results showed that PPO was purified from lotus rhizome by DEAE-52 anion exchange chromatography and Sephadex G-100 gel filtration chromatography, with its optimum substrate being determined as pyrogallic acid. Spectrophotometric and polarographic assays demonstrated that AA exhibited strong inhibitory activity against PPO. Thermodynamics, fluorescence, and circular dichroism spectral analysis showed that hydrophobic interactions caused the formation of AA-PPO complex, leading to the remarkable fluorescence quenching and conformational change of PPO. Atomic force microscopic analysis revealed that binding to AA induced significant changes in the surface morphology and molecular aggregation of PPO molecules. In this study, the interaction mechanism between PPO and AA was proposed for the first time, which provided a theoretical basis for AA to inhibit lotus rhizome browning. PRACTICAL APPLICATIONS: Lotus rhizome, an aquatic vegetable, is prone to enzymatic browning in processing operations, which leads to a decrease in market value and economic loss. At present, ascorbic acid (AA) is widely used in industries as an excellent antioxidant because of its good antibrowning effect and relatively low cost. However, the interaction between the enzymatic browning-related polyphenol oxidase (PPO) from lotus rhizome and ascorbic acid has not been clearly studied. Understanding the mechanism of inhibiting PPO will help to prevent vegetable browning, especially fresh-cut products. The inhibitory effect of AA on PPO in lotus rhizome favors simultaneous use with other types of PPO inhibitors because of their likely synergistic effects.

Phytochemicals and Immunomodulatory Effect of Nelumbo nucifera Flower Extracts on Human Macrophages

This research characterizes phytochemicals inherent in lotus flower and investigates the antioxidant and immunomodulatory activity of ethyl acetate (EA) and ethyl alcohol (ET) lotus petal extracts. In the experiment, human monocytes-derived macrophages were stimulated by lipopoly-saccharide to mimic bacteria-induced inflammation. The results showed that ferulic acid, couma-rin, and chlorogenic acid were three dominant polyphenols. The EA and ET lotus petal extracts also possessed high antioxidant capability. Furthermore, the extracts exhibited immunomodulatory properties by suppressing TNF-α secretion in inflammatory-induced human macrophages by in-hibiting NF-κB-dependent inflammatory response. In essence, the lotus petal extracts possess reme-dial attributes beneficial to individuals afflicted with declined immune functions.

Quantitative Assessment of Abiotic Stress on the Main Functional Phytochemicals and Antioxidant Capacity of Wheatgrass at Different Seedling Age

The wheat seedlings of 6 days old were daily subjected to ultraviolet irradiation (irradiating for 5, 10, 20, 40, and 60 min/day, respectively), Polyethylene glycol 6000 (5, 10, 15, 20, 25% in 1/2 Hoagland solution, respectively), and salinity solution (10, 25, 50, 100, 200 mM in 1/2 Hoagland solution, respectively), while the control group (CK) was supplied only with the Hoagland solution. The wheatgrass was harvested regularly seven times and the total soluble polysaccharides, ascorbic acid, chlorophyll, total polyphenol, total triterpene, total flavonoid, and proanthocyanins content were tested. The antioxidant capacity was evaluated through 2,2'-azino-bis (3-ethylbenzthia-zoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and ferric ion reducing power. Technique for order preference by similarity to ideal solution (TOPSIS) mathematical model was adopted to comprehensively assess the functional phytochemicals of the different treatments. The results showed that the accumulation patterns of phytochemicals under abiotic stress were complex and not always upregulated or downregulated. The antioxidant activity and functional phytochemicals content of wheatgrass were significantly affected by both the stress treatments and seedling age, while the latter affected the chemicals more efficiently. The top five highest functional phytochemicals were observed in the 200 mM NaCl treated group on the 21st and 27th day, 25% PEG treated group on the 24th day, 200 mM NaCl treated group on the 24th day, and the group of 40 min/day ultraviolet exposure on 27th day.

Comprehensive characterization of lotus root polysaccharide-phenol complexes

To explore the effects of phenolic binding on the structure and activity of lotus root polysaccharides (LRPs), five LRP-phenol complexes containing catechin (61.22 mg/g), gallic acid (9.37 mg/g), ferulic acid (29.28 mg/g), chlorogenic acid (83.80 mg/g) or caffeic acid (14.80 mg/g) were prepared via noncovalent intermolecular interaction, respectively. The interaction was confirmed by the differences among LRPs, phenols and their complexes in ultraviolet-visible and Fourier-transform infrared spectra. The phenolic binding caused significant changes in the molecular weight (MW) distribution and aggregation behavior of LRPs, particularly their average MW (34.49 kDa) increased by 3.73-8.30 times. Compared to LRPs, the complexes all showed stronger antioxidant activities. Notably, the binding of catechin improved the macrophage-stimulating effect of LRPs, specifically promoting the NO production at normal condition and inhibiting the NO overproduction induced by lipopolysaccharide. The noncovalent interaction with phenolic compounds is a promising method for the structural and functional improvement of LRPs.

Comparative Analysis of Chemical Constituents in Different Parts of Lotus by UPLC and QToF-MS

Six parts of lotus (seeds, leaves, plumule, stamens, receptacles and rhizome nodes) are herbal medicines that are listed in the Chinese Pharmacopoeia. Their indications and functions have been confirmed by a long history of clinical practice. To fully understand the material basis of clinical applications, UPLC-QToF-MS combined with the UNIFI platform and multivariate statistical analysis was used in this study. As a result, a total of 171 compounds were detected and characterized from the six parts, and 23 robust biomarkers were discovered. The method can be used as a standard protocol for the direct identification and prediction of the six parts of lotus. Meanwhile, these discoveries are valuable for improving the quality control method of herbal medicines. Most importantly, this was the first time that alkaloids were detected in the stamen, and terpenoids were detected in the cored seed. The stamen is a noteworthy part because it contains the greatest diversity of flavonoids and terpenoids, but research on the stamen is rather limited.

Effect of ultraviolet treatment on shelf life of fresh lotus root

The potential use of ultraviolet (UV)-C (254 nm) to extend postharvest shelf life of fresh unprocessed lotus root (Nelumbo nucifera G.) was determined. UV treatment for 30 and 60 min effectively reduced weight loss, improved moisture, color retention, and soluble solids of samples when stored at 25°C for 15 days. Microbial growth inhibition of UV was evidenced by 1.8 and 1.0 log reductions in the 30 and 60 min-treated samples. Phenylalanine ammonia lyase (PAL) activity and total phenol contents (TPCs) detected in lotus root were higher, while oxidative enzymes peroxidase (POD) and polyphenol oxidase (PPO) were inhibited by UV treatment. Gallic acid, gallocatechin, and catechin levels were increased in 30 min-treated samples by about 0.9, 13.4, 8.0 mg/100 g. The results suggest that extension of postharvest storage life by UV-C is most likely through the protective roles exerted from stimulation of the phenylpropanoid pathway in the treated roots. PRACTICAL APPLICATIONS: Unlike previous studies that are mainly focused on shelf life extension of processed products of the rhizome, this study determines the potential use of a nonchemical and ecologically friendly ultraviolet (UV-C) treatment to extend shelf life of intact uncut fresh lotus root. Our results demonstrated that UV-C treatment significantly prolonged the shelf life of lotus root. Use of this method is promising as a treatment to improve postharvest storage life of fresh lotus root, to improve its export potential and help to address unmet local demands for the crop.

Transcription Profiles Reveal the Regulatory Synthesis of Phenols during the Development of Lotus Rhizome (Nelumbo nucifera Gaertn)

Lotus (Nelumbo nucifera Gaertn) is a wetland vegetable famous for its nutritional and medicinal value. Phenolic compounds are secondary metabolites that play important roles in the browning of fresh-cut fruits and vegetables, and chemical constituents are extracted from lotus for medicine due to their high antioxidant activity. Studies have explored in depth the changes in phenolic compounds during browning, while little is known about their synthesis during the formation of lotus rhizome. In this study, transcriptomic analyses of six samples were performed during lotus rhizome formation using a high-throughput tag sequencing technique. About 23 million high-quality reads were generated, and 92.14% of the data was mapped to the reference genome. The samples were divided into two stages, and we identified 23,475 genes in total, 689 of which were involved in the biosynthesis of secondary metabolites. A complex genetic crosstalk-regulated network involved in the biosynthesis of phenolic compounds was found during the development of lotus rhizome, and 25 genes in the phenylpropanoid biosynthesis pathway, 18 genes in the pentose phosphate pathway, and 30 genes in the flavonoid biosynthesis pathway were highly expressed. The expression patterns of key enzymes assigned to the synthesis of phenolic compounds were analyzed. Moreover, several differentially expressed genes required for phenolic compound biosynthesis detected by comparative transcriptomic analysis were verified through qRT-PCR. This work lays a foundation for future studies on the molecular mechanisms of phenolic compound biosynthesis during rhizome formation.

Antioxidant and Anti-Inflammatory Activities of Fractions from Bidens engleri O.E. Schulz (Asteraceae) and Boerhavia erecta L. (Nyctaginaceae)

Background: According to recent studies, reactive oxygen is the leader of human metabolic disease development. The use of natural antioxidants is the best way to stop or prevent this problem. Therefore, the aim of this study was to evaluate the antioxidant and anti-inflammatory activities and to determine the polyphenolic contents of the Bidens engleri and Boerhavia erecta fractions. Methods: Plant fractions were obtained using Soxhlet procedures with hexane, dichloromethane, acetonitrile, ethyl acetate, methanol, and butanol solvent, successively. The different fractions were compared according to their antioxidant, anti-inflammatory activities, total phenolic, and total flavonoid contents. The phenolic contribution to the biological activity was evaluated. Result: The Bidens engleri and Boerhavia erecta fractions showed the highest antioxidant abilities, notably the polar fractions, which inhibited significantly the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-O-azinobis(3-ethylbenzoline-6-sulphonate) (ABTS). The butanol fraction from Bidens engleri and methanol fraction from Boerhavia erecta have presented the best iron (III) reduction power with 211.68 and 198.55 mgAAE/g, respectively. Butanol and acetonitrile were the best solvents for extracting phenolic compounds from Bidens engleri and Boerhavia erecta, respectively. In contrast, dichloromethane was the best solvent for extracting a flavonoid from two plants with anti-COX-2 and anti-LOX-15 active compounds. The phenolic compound contributed significantly to antioxidant activity (r > 0.80). Conclusion: The Bidens engleri and Boerhavia erecta fractions possessed a potential antioxidant for fighting oxidative stress and helping to prevent diabetes, hypertension, and cardiovascular diseases. The uses of this plant could be promoted in Burkina Faso.

Fingerprint profiling of polysaccharides from different parts of lotus root varieties

Thirty-nine polysaccharides isolated from different parts of 13 lotus root varieties were characterized with fingerprint and chemometrics analyses to explore their similarity and diversity. The physicochemical features of lotus root polysaccharides (LRPs) were found to be the following: LRPs contained mainly polysaccharides (5.94 kDa) and polysaccharide-protein complexes (11.57 kDa and 5.30 kDa); their carbohydrates were composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose and arabinose approximately in the molar ratio of 0.19 : 0.14 : 0.08 : 0.17 : 6.49 : 1.00 : 0.16; and node LRPs possessed more binding proteins and uronic acids than both flesh and peel LRPs. Their fingerprints based on Fourier-transform infrared spectroscopy, pre-column derivatization high-performance liquid chromatography and high performance size-exclusion chromatography all exhibited relatively high similarities, contributing to the common figerprint models which could be utilized as references for the identification of LPRs. In addition, the fingerprint characteristics associated with the between-group variability of LRPs in the score plots derived from multivariate analytical models might indicate which variety or part of lotus root they were isolated from. Therefore, multi-fingerprinting techniques have the potential to be applied to the identification and quality control of LRPs.

Thirty-nine polysaccharides isolated from lotus roots were characterized with fingerprint and chemometrics analyses to explore their similarity and diversity.

Comparative evaluations on phenolic antioxidants of nine adulterants and anti-inflammation of four alternatives with their original herb Erycibe schmidtii

Erycibe schmidtii is widely used as folk medicine in China for treatments of various inflammations.