Research Progress of Quinoa Seeds (Chenopodium quinoa Wild.): Nutritional Components, Technological Treatment, and Application.

Quinoa (Chenopodium quinoa Wild.) is a pseudo-grain that belongs to the amaranth family and has gained attention due to its exceptional nutritional properties. Compared to other grains, quinoa has a higher protein content, a more balanced amino acid profile, unique starch features, higher levels of dietary fiber, and a variety of phytochemicals. In this review, the physicochemical and functional properties of the major nutritional components in quinoa are summarized and compared to those of other grains. Our review also highlights the technological approaches used to improve the quality of quinoa-based products. The challenges of formulating quinoa into food products are addressed, and strategies for overcoming these challenges through technological innovation are discussed. This review also provides examples of common applications of quinoa seeds. Overall, the review underscores the potential benefits of incorporating quinoa into the diet and the importance of developing innovative approaches to enhance the nutritional quality and functionality of quinoa-based products.

Comparison of the contents of phenolic compounds including flavonoids and antioxidant activity of rice (Oryza sativa) and Chinese wild rice (Zizania latifolia).

The contents of phenolic compounds, especially flavonoids, and antioxidant activity of rice (Oryza sativa, Os) and Chinese wild rice (Zizania latifolia, Zl) harvested in China were compared. Zl possessed significantly higher contents of total phenolics, flavonoids, and proanthocyanidins and exhibited higher antioxidant activity than in the Os Xian group, the Os Geng group, and red rice. The flavonoid contents of Os and Zl were compared using a UHPLC-QqQ-MS-based metabolomics approach. A total of 159 flavonoids were identified, among which 78 showed differential expression (72 up-regulated and six down-regulated in the Zl group). The Kyoto Encyclopaedia of Genes and Genomes annotation and classification indicated that the differentially expressed flavonoids were mainly related to anthocyanin biosynthesis. Moreover, candidate genes for flavonoid biosynthesis in Os and Zl were identified in this study. Compared with non-pigmented and red rice, Zl may be more nutritious and is thus considered a better source of natural antioxidants.

Effect of baking on the flavor stability of green tea beverages.

Flavor stability is important for the quality of tea beverages. Baking is a typical processing technology to improve the flavor of tea leaves. In present study, seven raw tea materials, including steamed spring and autumn tea leaves, pan-fired spring tea leaves, and their corresponding baked tea leaves, were used to investigate the effect of baking on flavor stability of green tea beverages. The results showed that tea beverages prepared with baked tea had better flavor stability. The baking process obviously changed the concentrations of some important flavor substances, especially the aromatic pyrrole substances from 0 (unbaked) to 338.13 µg/L (baked) in tea beverages. Heat treatment had little influence on the flavor of tea beverages prepared from baked tea, but caused great changes in non-volatile and volatile components in those prepared from unbaked leaves. These results could help guide the processing of tea beverages which would improve their flavor quality stability.

Castanopsis lamontii Water Extract Shows Potential in Suppressing Pathogens, Lipopolysaccharide-Induced Inflammation and Oxidative Stress-Induced Cell Injury.

Castanopsis lamontii is traditionally used to prevent inflammatory diseases such as periodontitis and pharyngitis by residents in southwest China. However, little scientific evidence has been found to support this. In this research, the antibacterial activities of Castanopsis lamontii water extract (CLE) were assessed using the micro-dilution method. The anti-inflammatory and antioxidant activities of CLE were investigated in RAW264.7 cells. Key bioactive compounds in CLE were also explored. Results showed that CLE was capable of inhibiting the periodontitis pathogen Porphyromonas gingivalis and the pharyngitis pathogen ß-hemolytic Streptococcus. It suppressed lipopolysaccharide-induced inflammation in RAW 264.7 cells via inactivating the TLR4/NF-κB pathway. Besides, it reduced oxidative stress-induced cell injury via scavenging reactive oxygen species. Chemical composition analysis revealed that CLE was rich in epicatechin and procyanidin B2. Further studies confirmed that epicatechin predominantly contributed to the antibacterial activities of CLE, while procyanidin B2 was mainly responsible for the anti-inflammatory activities of CLE. Both compounds contributed to the antioxidant activities of CLE. Acute oral toxicity tests proved that CLE was practically non-toxic. These results provide experimental evidences of the health-beneficial effects of CLE and may help promote the application of CLE in the food and health industries.

Improving the taste of autumn green tea with tannase.

Green tea processed from autumn leaves is more bitter and astringent than that from spring leaves, mainly due to gallated catechins. The present study aimed to improve the taste of autumn green tea and green tea infusion by using tannase to treat tea leaves and tea infusion. The results showed that, after hydrolysis, the sweet aftertaste and overall acceptability improved, and the ratio of gallated catechins decreased, as did the bitterness and astringency of the autumn green tea. The pH value was significantly correlated with the concentrations of gallated catechins (r = 0.930, p < 0.01), non-gallated catechins (r = -0.893, p < 0.01), and gallic acid (r = 0.915, p < 0.01), as well as with the intensities of bitterness, astringency, and sweet aftertaste during hydrolysis. Gallic acid contributed to the sweet aftertaste of green tea infusion. These results will help to improve autumn green tea products with tannase.

A novel chitosan formulation treatment induces disease resistance of harvested litchi fruit to Peronophythora litchii in association with ROS metabolism.

This study aimed to investigate the effects of a novel chitosan formulation (Kadozan) treatment on disease development, response of disease resistance, metabolism of reactive oxygen species (ROS) in Peronophthora litchii-inoculated "Wuye" litchis. Compared with P. litchii-inoculated litchis, Kadozan-treated P. litchii-inoculated litchis exhibited lower fruit disease index, higher lignin content, higher activities of disease resistance-related enzymes (CHI, GLU and PAL), lower O2- generating rate and malondialdehyde content, higher activities of ROS scavenging enzymes (SOD, CAT and APX), higher contents of ascorbic acid and glutathione, and higher levels of reducing power and DPPH radical scavenging activity. These results suggest that Kadozan can be used to inhibit the growth of P. litchii in harvested litchis owning to the enhancement of disease resistance and ROS scavenging capacity, and decreases in O2- accumulation and membrane lipid peroxidation. Kadozan treatment can be used as a facile and novel method for suppressing postharvest pathogenic disease of litchis.

Influence of Extraction Conditions on Ultrasound-Assisted Recovery of Bioactive Phenolics from Blueberry Pomace and Their Antioxidant Activity.

The increase in diet-related chronic diseases has prompted the search for health-promoting compounds and methods to ensure their quality. Blueberry pomace is a rich yet underutilized source of bioactive polyphenols. For these high-value bioactive molecules, ultrasound-assisted extraction (USAE) is an attractive and green alternative to conventional extraction techniques for improving purity and yields. This study aimed to assess the impact of USAE parameters (sonication time, solvent composition, solid/liquid ratio, pH and temperature) on the recovery of phenolic compounds from blueberry pomace and antioxidant activity of the extracts. Total phenolic, flavonoid and anthocyanin contents (TPC, TFC and TAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity were analysed. USAE in 50% ethanol/water was the most efficient, yielding the highest TPC (22.33 mg/g dry matter (DM)), TFC (19.41 mg/g DM), TAC (31.32 mg/g DM) and DPPH radical scavenging activity (41.79 mg Trolox/g DM). USAE in water showed the lowest values even at low (1/40) solid/liquid ratio (7.85 mg/g DM, 3.49 mg/g DM, and 18.96 mg/g DM for TPC, TFC and TAC, respectively). Decreasing the solid/liquid ratio in water or 50% ethanol significantly increased TPC, TFC, TAC and DPPH radical scavenging. With ethanol, increasing the temperature in the range 20⁻40 °C decreased TPC but increased TFC and DPPH radical scavenging activity. Anthocyanin profiles of water and ethanolic extracts were qualitatively similar, consisting of malvidin, delphinidin, petunidin and cyanidin. These findings indicate that USAE is a method of choice for extracting high-value bioactive phenolics from blueberry pomace. Selective enrichment of different phenolic fractions is possible under select extraction conditions.

Phenolic Compositions and Antioxidant Activities Differ Significantly among Sorghum Grains with Different Applications.

Sorghum grains with different applications had different phenolic profiles, which were corresponded to various antioxidant capacities. In this study, total phenolic, proanthocyanidins and flavonoids contents, as well as contents of individual phenolic compounds from sorghum grains with various applications were determined, and their antioxidant capacities were evaluated. Total phenolic contents (TPC) and total proanthocyanidins contents (TPAC) showed strong correlation with antioxidant activities (r > 0.95, p < 0.01). Hongyingzi (S-1), one of the brewing sorghums, showed the highest level of TPC and TPAC, while white grain sorghum (S-8) had the lowest. Except for black grain sorghum (S-7), that contained the highest contents of ferulic acid, brewing sorghum grains contained the higher contents of the most individual phenolic compounds, especially the variety S-1. The correlation among individual phenolic compounds and antioxidant activities indicated that the free forms of protocatechuic acid (r = 0.982 of FRAPassay, p < 0.01) and taxifolin (r = 0.826 of FRAP assay, p < 0.01) may be the main functional compounds. These results indicate that brewing sorghum grains can also be utilized as effective materials for functional foods.

Pectin from Citrus Canning Wastewater as Potential Fat Replacer in Ice Cream.

Pectin had been recovered from canning wastewater produced by chemical treatment of segment membrane during preparation of canned citrus in our previous research. The purpose of this study was to characterize the extracted pectin from canning wastewater, and to evaluate its application as a fat alternative to replace fat in ice cream. The monosaccharide composition and rheological properties of the pectin were determined. The influences of fat reduction and pectin addition on the physicochemical, rheological and sensory properties of low-fat ice cream were determined. The rheological results showed that pectin solutions were typical pseudoplastic fluids. The addition of pectin in ice cream can cause an increase in viscosity, overrun, and hardness, and a decrease in meltdown of the ice cream. When 0.72% pectin (w/w) is incorporated into ice cream, a prototype product of ice cream with 45% lower fat content compared to the control was made. Results indicated that their qualities such as appearance, flavor, and taste were not significantly different. The low-fat ice cream had higher smoothness scores and lower mouth-coating scores. Hence, pectin extracted from citrus canning wastewater can be potentially used as fat replacer in ice cream, which benefits both the environment and the food industry.

Quality development and main chemical components of Tieguanyin oolong teas processed from different parts of fresh shoots.

The Tieguanyin oolong tea is popular in China. However, the quality development and chemical change during processing were still unclear. This study aimed to investigate the chemical compositions and quality of Tieguanyin oolong teas processed from different leaves of fresh shoots. The results showed the fermentation degree of oolong teas decreased from the first leaves to the fourth-fifth leaves, and was associated with the changes in infusion color (b∗) and chroma, as well as the contents of total theaflavins, (E)-nerolidol and indole. After shaking and setting, the differences in the water contents and the activities of polyphenoloxidase, peroxidase, and ß-glucosidase of the tea leaves, significantly influenced the oxidation of catechins. The hydrolysis of volatile compounds might influence the fermentation degrees of the oolong teas processed from different leaves of fresh shoots. The results generated from the present study can be used in guiding the production of oolong teas.

Effects of a novel chitosan formulation treatment on quality attributes and storage behavior of harvested litchi fruit.

The effects of Kadozan (a novel chitosan formulation) treatment on physiological attribute, nutritional quality and storage behavior of harvested "Wuye" litchi fruit were studied. Compared with control litchis, Kadozan treatment significantly decreased fruit respiration rate, retarded the increase of pericarp cell membrane permeability, maintained higher contents of anthocyanins and flavonoids and higher values of L∗, a∗ and b∗ in litchi pericarp, and reduced the decreases of titratable acidity, total soluble solids, total soluble sugars, and vitamin C contents in litchi pulp, maintaining better quality of litchis. Furthermore, Kadozan treatment decreased browning index and disease index of litchis, kept higher rate of commercially acceptable fruit, and reduced fruit weight loss, showing better storage behavior of litchis under ambient temperature. The optimal Kadozan treatment for litchis was the 1:100 (VKadozan: VKadozan + Water) dilution, which might be a promising method for keeping quality and prolonging shelf-life of harvested "Wuye" litchi fruit.

Physicochemical characteristics and immunomodulatory activities of three polysaccharide-protein complexes of longan pulp.

Three polysaccharide-protein complexes of longan pulp (LP1-3) were isolated in this work. Their physicochemical characteristics and immunomodulatory effects on splenocytes, natural killer (NK) cells and macrophages in vitro were investigated. The carbohydrate portions of LP1-3 were principally composed of glucose, arabinose and mannose. LP3 displayed the maximal moisture absorption, and the thermal stability of LP2 was obviously higher than that of LP1 and LP3. All of them showed the characteristic polysaccharide and protein bands in the Fourier Transform Infrared (FTIR) spectrum. For a certain dose, all the fractions could significantly stimulate splenocyte proliferation, macrophage phagocytosis against neutral red, and NK cell cytotoxicity against YAC-1 lymphoma cell (P < 0.05). The results demonstrated that the polysaccharide-protein complexes of longan pulp have medical potential as immunotherapeutic adjuvants due to their immunomodulatory activities.

Effect of girdling at various positions of 'Huang Zhi Xiang' tea tree (Camellia sinensis) on the contents of catechins and starch in fresh leaf.

The contents of starch and catechins in the fresh leaf of 'Huang Zhi Xiang' Oolong tea trees girdled at the bottom, middle (on the big branches) and top (on the small branches) were determined. The study demonstrated that the starch contents from girdled trees were significantly higher (p<0.05) than that from non-girdled ones. Furthermore, the contents of (-)-epicatechin (EC), (-)-epigallocatechin (EGC), total catechins (TC) and simple catechins (SC) from girdled trees were significantly higher (p<0.05) than those from non-girdled ones. Especially, the contents of (-)-epigallocatechin gallate (EGCG), (-)-epicatechin gallate (ECG) and catechin gallate (CG) from girdled at the middle were also significantly higher (p<0.05) than those from the non-girdled. The starch contents were negatively correlated with the contents of (-)-gallocatechin (GC), EC, SC, TC and EGC, while positively correlated with the contents of EGCG and CG in fresh shoots.

Wound-healing properties of the oils of Vitis vinifera and Vaccinium macrocarpon.

Vitis vinifera (grape) and Vaccinium macrocarpon (cranberry) are well known medicinal plants; most of the pharmacologically active phytochemicals have been isolated from the skin, fruit juice, fermented extract and alcohol fractions of the plants above. Here, the pharmacological properties of the phytochemical constituents present in oils of cranberry and grape were investigated. The oil of grape and cranberry has been evaluated for their wound healing activity by using an excision wound model in rats. The animals were divided into four groups of six each (n = 6). The experimental group 1 and 2 animals were treated topically with the grape and cranberry oil (100 mg/kg body weight), respectively. The controls were treated with petroleum jelly. The standard group of animals were treated with mupirocin ointment (100 mg/kg body weight). The healing was assessed by the rate of wound contraction and hydroxyproline content. On day 13, animals treated with cranberry oil exhibited a (88.1%) reduction in the wound area compared with grape-oil treated (84.6%), controls (74.1%) and standard group animals (78.4%) (p < 0.001). The hydroxyproline content of the granulation tissue was significantly higher in the animals treated with cranberry and the grape-oil (p < 0.000). Comparative investigation of the curative properties of the oils of V. vinifera and V. macrocarpon revealed a significant result which suggests their wound-healing potential.

Wound-healing activity of the skin of the common grape (Vitis Vinifera) variant, Cabernet Sauvignon.

The common Grape L. (Vitaceae) is regarded as an important medicinal plant. European healers have suggested the use of grapevine sap, juice, and whole grape in the treatment of pain, allergic reactions, inflammation, and to promote wound healing. We evaluated grape-skin powder for its wound-healing activity using an excision wound model in rats. Animals were randomly divided into three groups of six (n = 6) each. The test group animals were treated topically with the grape-skin powder (100 mg/kg/day). The controls and standard group animals were treated with petroleum jelly and mupirocin ointment respectively. Healing was assessed by the rate of wound contraction, period of epithelialization, and hydroxyproline content. On day 13, treatment of the wounds with grape-skin powder enhanced significantly the rate of wound contraction (100 %). Treated animals showed significant decrease in the epithelialization period (p < 0.000) and increase in the hydroxyproline content (p < 0.05) when compared to control and the standard. Histological analysis was also consistent with the proposal that grape-skin powder exhibits significant wound-healing potential. Increased rate of wound contraction, hydroxyproline content, and decrease in epithelialization time in the treated animals support the use of grape-skin powder in the management of wound healing.

Enhanced antioxidant and antityrosinase activities of longan fruit pericarp by ultra-high-pressure-assisted extraction.

The health benefits of fruits acting against chronic diseases are ascribed to their antioxidant activities which are mainly responsible due to the presence of phenolic compounds. The use of ultra-high-pressure-assisted extraction (UHPE) has shown great advantages for the extraction of these phenolic compounds from longan fruit pericarp (LFP). Studies were carried out to investigate the effects of UHPE at pressures of 200, 300, 400 and 500 MPa on total phenolic contents, extraction yield, antioxidant and antityrosinase activities from LFP. The antioxidant activities of these extracts were analyzed, using various antioxidant models like 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, total antioxidant capacity and superoxide anion radical scavenging activity. Extract from ultra-high-pressure-assisted extraction at 500MPa (UHPE-500) showed the highest antioxidant activities of all the tested models. In addition, it also showed moderate tyrosinase inhibitory activity. Three phenolic acids, namely gallic acid, ellagic acid, and corilagin were identified and quantified by HPLC. Corilagin content was the highest compared to other phenolic acids identified. UHPE-500 obtained the higher phenolic acid contents compared to other high pressure processing and conventional extractions (CE). Compared with CE, UHPE-500 exhibited good extraction effectiveness in terms of higher extraction yields with high phenolic contents and also with higher antioxidant and antityrosinase activities.

Purification and identification of antioxidant peptides from grass carp muscle hydrolysates by consecutive chromatography and electrospray ionization-mass spectrometry.

Grass carp muscles were hydrolyzed with various proteases (papain, bovine pancreatin 6.0, bromelain, neutrase 1.5MG and alcalase 2.4L) to extract antioxidant peptides. The hydrolysates were assessed using methods of hydroxyl radical scavenging ability and lipid peroxidation inhibition activity. Hydrolysate prepared with alcalase 2.4L was found to have the highest antioxidant activity. It was purified using ultrafiltration and consecutive chromatographic methods including ion-exchange chromatography, multilayer coil high-speed counter-current chromatography, and gel filtration chromatography. The purified peptide, as a potent antioxidant, was identified as Pro-Ser-Lys-Tyr-Glu-Pro-Phe-Val (966.3Da) using RP-HPLC connected on-line to an electrospray ionization mass spectrometry. As well, it was found that basic peptides had greater capacity to scavenge hydroxyl radical than acidic or neutral peptides and that hydrophobic peptides contributed more to the antioxidant activities of hydrolysates than the hydrophilic peptides. In addition, the amino acid sequence of the peptide might play an important role on its antioxidant activity.

Seasonal variations of phenolic compounds in Australia-grown tea (Camellia sinensis).

Seasonal variations of phenolic compounds in fresh tea shoots grown in Australia were studied using an HPLC method. Three principal tea flavanols [epigallocatechin gallate (EGCG), epicatechin gallate (ECG), and epigallocatechin (EGC)] and four grouped phenolics [total catechins (Cs), total catechin gallates (CGs), total flavanols (Fla), and total polyphenols (PPs)] in fresh tea shoots were analyzed and compared during the commercial harvest seasons from April 2000 to May 2001. The levels of EGCG, ECG, and CGs in the fresh tea shoots were higher in the warm months of April 2000 (120.52, 34.50, and 163.75 mg/g, respectively) and May 2000 (128.63, 44.26, and 183.83 mg/g, respectively) and lower during the cool months of July 2000 (91.39, 35.16, and 132.30 mg/g, respectively), August 2000 (91.31, 31.56, and 128.64 mg/g, respectively), and September 2000 (96.12, 33.51, and 136.90 mg/g, respectively). Thereafter, the levels increased throughout the warmer months from October to December 2000 and remained high until May 2001. In the warmer months, the levels of EGCG, ECG, and CGs were in most cases significantly higher (P < 0.05) than those in the samples harvested in the cooler months. In contrast, the levels of EGC and Cs were high and consistent in the cooler months and low in the warmer months. The seasonal variations of the individual and grouped catechins were significant (P < 0.05) between the cooler and warmer months. This study revealed that EGCG and ECG could be used as quality descriptors for monitoring the seasonal variations of phenolics in Australia-grown tea leaves, and the ratio (EGCG + ECG)/EGC has been suggested as a quality index for measuring the differences in flavanol levels in fresh tea shoots across the growing seasons. Mechanisms that induce seasonal variations in tea shoots may include one or all three of the following environmental conditions: day length, sunlight, and/or temperature, which vary markedly across seasons. Therefore, further studies under controlled conditions such as in a greenhouse may be required to direct correlate flavonoid profiles of green tea leaves with their yields and also to with conditions such as rainfall and humidity.

Saponins from edible legumes: chemistry, processing, and health benefits.

Demand for bean products is growing because of the presence of several health-promoting components in edible bean products such as saponins. Saponins are naturally occurring compounds that are widely distributed in all cells of legume plants. Saponins, which derive their name from their ability to form stable, soaplike foams in aqueous solutions, constitute a complex and chemically diverse group of compounds. In chemical terms, saponins contain a carbohydrate moiety attached to a triterpenoid or steroids. Saponins are attracting considerable interest as a result of their diverse properties, both deleterious and beneficial. Clinical studies have suggested that these health-promoting components, saponins, affect the immune system in ways that help to protect the human body against cancers, and also lower cholesterol levels. Saponins decrease blood lipids, lower cancer risks, and lower blood glucose response. A high saponin diet can be used in the inhibition of dental caries and platelet aggregation, in the treatment of hypercalciuria in humans, and as an antidote against acute lead poisoning. In epidemiological studies, saponins have been shown to have an inverse relationship with the incidence of renal stones. Thermal processing such as canning is the typical method to process beans. This study reviews the effect of thermal processing on the characteristics and stability of saponins in canned bean products. Saponins are thermal sensitive. During soaking and blanching, portions of saponins are dissolved in water and lost in the soaking, washing, and blanching liquors. An optimum thermal process can increase the stability and maintain the saponins in canned bean products, which is useful for assisting the food industry to improve thermal processing technology and enhance bean product quality.

Antioxidative properties of lycopene and other carotenoids from tomatoes: synergistic effects.

Lycopene is the major carotenoid in tomatoes. Tomatoes contain a matrix of many bioactive components, including vitamin C, vitamin E, other carotenoids (a-, beta-, gamma- carotene, lutein), and flavonoids. Their synergistic interactions, when used in combination, may be responsible for the observed beneficial effects of tomato-based products. This study investigated the synergistic antioxidant activity of lycopene in combination with beta-carotene, vitamin E, and lutein. A liposome system was used to test the synergistic antioxidant activity. The carotenoid mixtures were more efficient in protecting liposome from oxidation than the individual carotenoid. Mixtures of lycopene and vitamin E appear to have the greatest synergistic antioxidant activity.