Optimization of extraction yield and antioxidant properties of Brassica oleracea Convar Capitata Var L. leaf extracts

Cabbage (Brassica oleracea var. capitata) Development in Time: How Differential Parenchyma Tissue Growth Affects Leafy Head Formation

This study aims to categorize the morphological changes during cabbage (B. oleracea ssp. capitata) development, seedling, rosette, folding, and heading, and to elucidate the cellular mechanisms of the leaf curvature, essential for the formation of the leafy head. We followed the growth of two cabbage cultivars with distinct head shapes (round and pointed) and one non-heading collard cultivar; we phenotyped the size and volume of the whole plant as well as the size, shape, and curvature of the leaves during growth. By integrating these phenotypic data, we determined the four vegetative stages for both cabbages. The histological phenotypes of microtome sections from five distinct leaf positions of the rosette, folding, and heading leaves at two timepoints during leaf growth were quantified and revealed variations in cellular parameters among leaf types, between leaf positions, and between the adaxial and abaxial sides. We identified two synergistic cellular mechanisms contributing to the curvature of heading leaves: differential growth across the leaf blade, with increased growth at the leaf's center relative to the margins; and the increased expansion of the spongy parenchyma layer compared to the palisade parenchyma layer, resulting in the direction of the curvature, which is inwards. These two processes together contribute to the typical leafy heads of cabbages.

Physicochemical and Functional Properties of Yeast-Fermented Cabbage

Microbial fermentation is often used to improve the functionality of plant-based food materials. Herein, we investigated changes in the physicochemical and functional properties of cabbage during yeast fermentation to develop new products using fermented cabbage. Among the 8 types of food-grade yeast, both Saccharomyces cerevisiae and Saccharomyces boulardii fermented 10% cabbage powder solution (w/w) the most effectively, leaving no soluble sugars after 12 h of fermentation. In addition, the yeast fermentation of cabbage resulted in functionally positive outcomes in terms of sulforaphane content, antioxidant properties, and anti-inflammatory activity. Specifically, the yeast-fermented cabbages contained about 500% more sulforaphane. The soluble fraction (5 μg/ml) of yeast-fermented cabbage had no cytotoxicity in murine RAW 264.7 cells, and the radical-scavenging capacity was equivalent to 1 μg/ml of ascorbic acid. Moreover, cabbage fermented with S. boulardii significantly suppressed both lipopolysaccharides (LPS)-induced nitric oxide production and LPS-induced reactive oxygen species production in RAW 264.7 cells, suggesting a potential anti-inflammatory effect. These results support the idea that yeast fermentation is promising for developing functionally improved cabbage products.

Green-Mediated Synthesis of NiCo2O4 Nanostructures Using Radish White Peel Extract for the Sensitive and Selective Enzyme-Free Detection of Uric Acid

The ability to measure uric acid (UA) non-enzymatically in human blood has been demonstrated through the use of a simple and efficient electrochemical method. A phytochemical extract from radish white peel extract improved the electrocatalytic performance of nickel-cobalt bimetallic oxide (NiCo2O4) during a hydrothermal process through abundant surface holes of oxides, an alteration of morphology, an excellent crystal quality, and increased Co(III) and Ni(II) chemical states. The surface structure, morphology, crystalline quality, and chemical composition were determined using a variety of analytical techniques, including powder X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS). The electrochemical characterization by CV revealed a linear range of UA from 0.1 mM to 8 mM, with a detection limit of 0.005 mM and a limit of quantification (LOQ) of 0.008 mM. A study of the sensitivity of NiCo2O4 nanostructures modified on the surface to UA detection with amperometry has revealed a linear range from 0.1 mM to 4 mM for detection. High stability, repeatability, and selectivity were associated with the enhanced electrochemical performance of non-enzymatic UA sensing. A significant contribution to the full outperforming sensing characterization can be attributed to the tailoring of surface properties of NiCo2O4 nanostructures. EIS analysis revealed a low charge-transfer resistance of 114,970 Ohms that offered NiCo2O4 nanostructures prepared with 5 mL of radish white peel extract, confirming an enhanced performance of the presented non-enzymatic UA sensor. As well as testing the practicality of the UA sensor, blood samples from human beings were also tested for UA. Due to its high sensitivity, stability, selectivity, repeatability, and simplicity, the developed non-enzymatic UA sensor is ideal for monitoring UA for a wide range of concentrations in biological matrixes.

Tissue specific changes of phytochemicals, antioxidant, antidiabetic and anti-inflammatory activities of tea [Camellia sinensis (L.)] extracted with different solvents

Different parts of Camellia sinensis (L.) were extracted with solvents according to polarity, and the extracts' phytochemical profiling and biological activities were examined. The total phenolic (TPC) and total flavonoid (TFC) contents increased with the increasing polarity of the solvent which met its maximum in polar solvents. The increasing antioxidant, anti-inflammatory and antidiabetic activities were recorded with increasing polarity of solvents which showed hydroalcoholic as best solvent. The strong and significant correlation was among the TPC, TFC, DPPH, anti-inflammatory and antidiabetic activities for different parts of tea. HPTLC study of individual phenolic acids, epigallocatechin gallate, gallocatechin and theaflavin met their maximum level of content with polar solvents like hydroalcohol, methanol and water mostly in mainly tea leaves. Our finding suggested that the polar solvents and young leaves of tea were beneficial for obtaining extracts. On the other hand, phenolics were found to be potent antioxidant, anti-inflammatory and antidiabetic agent.

Vanillic Acid as a Promising Xanthine Oxidase Inhibitor: Extraction from Amomum villosum Lour and Biocompatibility Improvement via Extract Nanoemulsion

Gout is an oxidative stress-related disease. Food-derived vanillic acid, a promising xanthine oxidase inhibitor, could potentially be used as a safe, supportive, and therapeutic product for gout. The extraction of vanillic acid from a classic Chinese herbal plant Amomum villosum with ethanol was investigated in the study. The optimum conditions were determined as extraction time of 74 min, extraction temperature of 48.36 °C, and a solid-to-liquid ratio of 1:35 g·mL⁻¹ using the Box–Behnken design (BBD) of response surface methodology (RSM). The experimental extraction yield of 9.276 mg·g⁻¹ matched with the theoretical value of 9.272 ± 0.011 mg·g⁻¹ predicted by the model. The vanillic acid in Amomum villosum was determined to be 0.5450 mg·g⁻¹ by high-performance liquid chromatography–diode array detection (HPLC–DAD) under the optimum extraction conditions and exhibited xanthine oxidase (XO) inhibitory activity, with the half-maximal inhibitory concentration (IC50) of 1.762 mg·mL⁻¹. The nanoemulsion of Amomum villosum extract consists of 49.97% distilled water, 35.09% S_mix (mixture of tween 80 and 95% ethanol with 2:1 ratio), and 14.94% n-octanol, with a particle size of 110.3 ± 1.9 nm. The nanoemulsion of Amomum villosum extract exhibited markable XO inhibitory activity, with an inhibition rate of 58.71%. The result demonstrated the potential benefit of Amomum villosum as an important dietary source of xanthine oxidase inhibitors for gout.

Cabbage (Brassica oleracea var. capitata): A food with functional properties aimed to type 2 diabetes prevention and management

Type 2 diabetes mellitus (T2DM) is increasing the prevalence worldwide at an alarming rate, becoming a serious public health problem that mainly affects developing countries. Functional food research is currently of great interest because it contributes to developing nutritional therapy strategies for T2DM prevention and treatment. Bioactive compounds identified in some plant foods contribute to human health by mechanisms of action that exert biological effects on metabolic pathways involved in the development of T2DM. Hence, vegetables with high bioactive compounds content may be a source of functional value for the control of T2DM. Cabbages varieties (Brassica oleracea var. capitata) such as green (GCB), white (WCB), and red (RCB) are foods consumed (raw or cooked) and cultivated in different regions of the world. Scientific evidence shows that cabbage has multi-target effects on glucose homeostatic regulation due to its high content of bioactive compounds. It has also been shown to decrease damage to organs affected by T2DM complications, such as the liver and kidney. Additionally, it could contribute as a preventive by attenuating problems underlying the development of T2DM as oxidative stress and obesity. This review highlights the functional properties of cabbage varieties involved in glucose regulation and the main mechanisms of the action exerted by their bioactive compounds. In conclusion, cabbage is a valuable food that can be employed as part of nutritional therapy or functional ingredient aimed at the prevention and treatment of T2DM.

Total and bioaccessible heavy metals in cabbage from major producing cities in Southwest China: health risk assessment and cytotoxicity

Green leafy vegetables are economical and nutritious, but they may be contaminated with heavy metals. In this study, we assessed the total and bioaccessible concentrations of As, Cd, Pb and Cr in a popular vegetable cabbage (Brassica oleracea) from four major producing cities in Yunnan, Southwest China. With the mean concentrations of As, Cd, Pb and Cr being 0.24, 0.20, 0.32 and 1.28 mg kg-1, the As, Cd and Pb concentrations were within the limits of 0.2-0.5 mg kg-1 based on Chinese National Standards and the WHO/FAO, but Cr concentration was 2.6-times greater than the limit of 0.5 mg kg-1. Based on an in vitro bioaccessibility assay of the Solubility Bioaccessibility Research Consortium (SBRC), As bioaccessibility was the lowest at 11% while those of Cd, Pb and Cr were much greater at 68-87%. The estimated daily intake (EDI) of metals through cabbage ingestion was similar for children and adults. Among the four metals, only Cr's EDI at 2.29-1.87 exceeded 1 based on total and bioaccessible concentrations. The high Cr concentration at 1.28 mg kg-1 coupled with its high bioaccessibility at 67.5% makes Cr of concern in cabbage. However, human gastrointestinal cells exposed to the gastric digesta with high bioaccessible heavy metals and risky EDI, showed no obvious cytotoxicity, indicating that existing models based on total or bioaccessible heavy metals may overestimate their human health risk. Taken together, to accurately assess the human health risk of heavy metals in cabbage, both total/bioaccessible concentrations and the gastrointestinal cell responses should be considered.

Phytotherapy and food applications from Brassica genus

Plants of the genus Brassica occupy the top place among vegetables in the world. This genus, which contains a group of six related species of a global economic significance, three of which are diploid: Brassica nigra (L.) K. Koch, Brassica oleracea L., and Brassica rapa L. and three are amphidiploid species: Brassica carinata A. Braun, Brassica juncea (L.) Czern., and Brassica napus L. These varieties are divided into oily, fodder, spice, and vegetable based on their morphological structure, chemical composition, and usefulness of plant organs. The present review provides information about habitat, phytochemical composition, and the bioactive potential of Brassica plants, mainly antioxidant, antimicrobial, anticancer activities, and clinical studies in human. Brassica vegetables are of great economic importance around the world. At present, Brassica plants are grown together with cereals and form the basis of global food supplies. They are distinguished by high nutritional properties from other vegetable plants, such as low fat and protein content and high value of vitamins, fibers along with minerals. In addition, they possess several phenolic compounds and have a unique type of compounds namely glucosinolates that differentiate these crops from other vegetables. These compounds are also responsible for numerous biological activities to the genus Brassica as described in this review.

Effect of particle size on functional properties of Brassica napobrassica leaves powder. Starch interactions and processing impact

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Size fractionation of vegetable by-product allows obtaining diverse functionality.

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In starchy systems, the addition of vegetable powder affected the pasting properties.

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Starch interaction with vegetable powder depended on the type of starch.

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Maize starch interacted more with phenolic compounds showing a protective effect.

The aim of this work was to determine the physicochemical and functional properties of a Brassica napobrassica leaves powder sieved at three particle sizes. Moreover, in order to understand the potential interactions between the Brassica napobrassica leaves powder and starch, the pasting properties were assessed and the effect of pH (4–9) and temperatures (70–90 °C) on the phenolic compounds and antiradical activities were also evaluated. Particle size had an effect on physicochemical and functional properties of the vegetable powder. Vegetable fractions affected the apparent viscosity of starch suspension along heating and cooling, with larger effect during heating. The effect of the processing conditions on the functional properties of starch suspensions was influenced by the powder particle sized and the type of starch used. Maize starch seemed to interact more with phenolic compounds than rice starch, which resulted in a protective effect against pH and temperature variations, leading to higher antiradical activities.

Phenolic Fingerprinting, Antioxidant, and Deterrent Potentials of Persicaria maculosa Extracts

Persicaria maculosa (Polygonaceae) (known as lady’s thumb) is an annual morphologically variable weed that is widely distributed in Chile. The purpose of this study was to investigate the antifeedant potential of methanolic (MeOH), ethanolic (EtOH), and dichloromethane (DCM) extracts from the aerial parts of this plant collected in the Valparaíso and Curicó provinces (Chile) and relate this activity to the antioxidant capacity and the presence of phenolic compounds in the extracts. A phenolic profile based on HPLC-ESI-MS/MS allowed the identification of 26 phenolic compounds, most of them glycosyl derivatives of isorhamnetin, quercetin, and kaempferol. In addition, the total phenolic content (TP), total flavonoids (TF), and antioxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion scavenging (O₂⁻), ferric-reducing antioxidant power (FRAP), and cupric-reducing antioxidant capacity (CUPRAC) of the extracts are reported. The antifeedant potentials of the plant extracts were tested against Epilachna paenulata, Pseudaletia adultera, Macrosiphum euphorbiae, and Diaphorina citri insects for the first time. The activity against the aphid M. euphorbiae was significant for the DCM extracts of plants from Valparaíso and Curicó (settling % = 23% ± 4% and 23% ± 5%, respectively). The antifeedant activities against the beetle E. paenulata and the lepidoptera P. adultera were significant for Valparaíso extracts, especially when tested against E. Paenulata (IFP = 1.0 ± 0.0). Finally, the MeOH and EtOH extracts from Valparaíso plants reduced the diet consumption of the psilid D. citri (p < 0.05). The results showed that P. maculosa is a good source of flavonoids with some antioxidant capacities and has potential interest as botanical eco-friendly alternative with deterrent activity.

Oxidative Leaching Kinetics of Vanadium from the Vanadium-Chromium-Reducing Residue with K2Cr2O7

Oxidative-alkaline leaching of vanadium from vanadium-chromium-reducing residues with K2Cr2O7 was investigated in this paper. The effects of processing parameters including dosage of NaOH, dosage of K2Cr2O7, reaction time, and reaction temperature on the leaching efficiency of vanadium were studied. The results simulated by response surface methodology indicated that vanadium leaching was affected significantly by the dosage of K2Cr2O7 and NaOH, and the processing parameters that affected the leaching efficiency of vanadium followed the order m(NaOH)/m(residue) > m(K2Cr2O7)/sssssm(residue) > reaction temperature > reaction time. The leaching efficiency of vanadium was up to 99.92% under optimal conditions: reaction temperature of 90 °C, reaction time of 60 min, liquid-to-solid ratio of 5:1 mL g-1, m(K2Cr2O7)/m(residue) = 0.10, and m(NaOH)/m(residue) = 0.30. The kinetics analysis indicated that diffusion through the product layer was the controlling step and the apparent activation energy for vanadium leaching was calculated to be 58.275 kJ·mol-1.

Efficient Removal of Hexavalent Chromium from Wastewater with Electro-Reduction

Removal of hexavalent chromium had attracted much attention as it is a hazardous contaminant. An electrocoagulation-like technology electro-reduction was applied. The chromium (VI) in the wastewater was reduced to chromium (III) by the electron supplied by electricity power and Fe2+, formed from corrosion of steel electrodes in acidic conditions. The mechanism and parameters affecting the reaction were investigated. The results optimized by response surface methodology indicated that the influence of single factor on the reduction efficiency followed the order: A: dosage of H2SO4 > C: reaction time > D: reaction temperature > B: current intensity. The reduction efficiency was hardly affected by current intensity, while it was increased with the increasing of reaction time and acid concentration. The reducing agent, Fe2+ an and extra free electron, acted as a reducing agent and could easily reduce hexavalent chromium to trivalent chromium at high temperatures in an acidic medium.

Volatile component interaction effects on compatibility of Cyperi Rhizoma and Angelicae Sinensis Radix or Chuanxiong Rhizoma by UPLC-MS/MS and response surface analysis

Cyperi Rhizoma (Xiangfu) combined with either Angelicae Sinensis Radix (Danggui) or Chuanxiong Rhizoma (Chuanxiong) are herb pairs that are commonly used in clinical settings. To illustrate the herb-herb interactions that occur when extracts from these herbs are obtained together, ultra-high-performance liquid chromatography coupled with triple quadrupole electrospray tandem mass spectrometry and response surface analysis were used. Volatile components, α-cyperone, nootkatone, ligustilide, senkyunolide A and senkyunolide I, were accurately identified with high precision. When Xiangfu was combined with Danggui at a 1:1 ratio, or with Chuanxiong at a 1:1 or 2:1 ratio, the dissolution rates of α-cyperone and nootkatone from the herbs were greatly increased, compared to those obtained from Xiangfu extract alone. The dissolution rates of ligustilide, senkyunolide A and senkyunolide I from Danggui or Chuanxiong changed proportionally to changes in the ratios of Xiangfu with either Danggui or Chuanxiong. Response surface analysis results presented polynomial regression equations between the dissolution of tested compounds and the corresponding input variables, including compatibility proportions and solvent dosage. Based on the predicted results from response surface analysis, a combination of Xiangfu with Chuanxiong at a ratio of near 1:1, or with Danggui at 1:2, resulted in the maximum dissolution of five volatile components. Our established method could be applied to herb-herb interaction research, and the results may provide a scientific basis for the development of Cyperi Rhizoma-Chuanxiong Rhizoma, or Cyperi Rhizoma-Angelicae Sinensis Radix-based formulas and products.