Canola Seed Protein: Pretreatment, Extraction, Structure, Physicochemical and Functional Characteristics.

The rapid growth of the global population has led to an unprecedented demand for dietary protein. Canola seeds, being a widely utilized oil resource, generate substantial meal by-products following oil extraction. Fortunately, canola meals are rich in protein. In this present review, foremost attention is directed towards summarizing the characteristics of canola seed and canola seed protein. Afterwards, points of discussion related to pretreatment include an introduction to pulsed electric field treatment (PEF), microwave treatment (MC), and ultrasound treatment (UL). Then, the extraction method is illustrated, including alkaline extraction, isoelectric precipitation, acid precipitation, micellization (salt extraction), and dry fractionation and tribo-electrostatic separation. Finally, the structural complexity, physicochemical properties, and functional capabilities of rapeseed seeds, as well as the profound impact of various applications of rapeseed proteins, are elaborated. Through a narrative review of recent research findings, this paper aims to enhance a comprehensive understanding of the potential of canola seed protein as a valuable nutritional supplement, highlighting the pivotal role played by various extraction methods. Additionally, it sheds light on the broad spectrum of applications where canola protein demonstrates its versatility and indispensability as a resource.

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.

Metabolomics and proteomics reveal the molecular basis of colour formation in the pericarp of Chinese wild rice (Zizania latifolia).

Chinese wild rice (Zizania latifolia) is rich in flavonoids and the characteristic colour of its pericarp is attributed to the flavonoids. In this study, the molecular basis of the colour change in the pericarp of Chinese wild rice was studied using metabolomics and proteomics. Whole seeds in three developmental stages (10, 20, and 30 days after flowering) were characterised based on phenolic contents, free amino acids (FAAs), and the expression level and activities of enzymes critical in flavonoid biosynthesis. The total phenolic and proanthocyanidin contents of Chinese wild rice increased gradually, whereas total flavonoid and FAA contents decreased during seed development. Metabolomic analysis revealed gradual upward trends for 57 flavonoids (sub classes 1, 3, and 10) related to colour change in the pericarp. Proteomic analysis showed that the phenylpropanoid biosynthesis metabolic pathway was enriched with differentially expressed proteins and was associated with flavonoid biosynthesis. Proteomic data suggested that leucoanthocyanidin reductase and WD40 repeat protein may be involved in flavonoid biosynthesis in Chinese wild rice, which was also verified by real-time quantitative PCR. Our results provide new insights into the understanding of the colour formation in the pericarp of Chinese wild rice.

Comparison of Phenolic and Flavonoid Compound Profiles and Antioxidant and α-Glucosidase Inhibition Properties of Cultivated Soybean (Glycine max) and Wild Soybean (Glycine soja).

Wild soybean (Glycine soja Sieb.et Zucc; WS) has been used as a traditional food in China for many years and contains significantly higher levels of isoflavones than cultivated soybean (Glycine max; CS), but the secondary metabolites, including flavonoids and the phenolic composition differences between them, remain unclear. The results showed that WS possessed significantly higher total phenolic and flavonoid content and exhibited better antioxidant and α-glucosidase inhibition activities as well as excellent protective effects against H2O2-induced oxidative injury in a human endothelial cell line. Through metabolomic analysis, 642 metabolites were identified, and 238 showed differential expression, with 151 upregulated and 87 downregulated. A total of 79 flavonoid compounds were identified, 42 of which were upregulated in WS. 2'-Hydroxygenistein, garbanzol, protocatechuic aldehyde, ligustilide, and resveratrol were the most discriminated compounds in WS. The metabolic pathway analysis of differential metabolites related to the biosynthesis of flavonoids and phenolic acids were the biosynthesis of phenylpropanoids, flavonoids, isoflavonoids, flavones, and flavonols. This study substantially elucidated differences in the content of flavonoids and biological activities between WS and CS, which is useful information for the effective utilization of these two black soybean species in food processing.

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.

Wild rice (Zizania spp.): A review of its nutritional constituents, phytochemicals, antioxidant activities, and health-promoting effects.

Wild rice (Zizania spp.), an important aquatic cereal grain in North America and East Asia, has attracted interest worldwide because of its antioxidant activities and health-promoting effects. Wild rice is high in protein, minerals, and vitamins but is low in fat. The phytochemical content (phytosterols, γ-oryzanol, γ-aminobutyric acid, phenolic acids, and flavonoids) of wild rice warrants its development as a functional food. Phenolic acids, flavonoids, and other phytochemicals from Zizania plants have pronounced antioxidant properties, which are associated with prevention of chronic diseases. The health-promoting effects of Zizania plants include alleviation of insulin resistance and lipotoxicity, atherosclerosis prevention, and anti-inflammatory, anti-allergic, anti-hypertensive, and immunomodulatory effects. Here, we provide an overview of Zizania research up to April 2020, focusing on the nutritional constituents, phytochemicals, antioxidant activities, and health-promoting effects of Zizania plants. This review has important implications for further investigations and applications of Zizania plants in medicine and as functional foods.

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.

Effects of NtSPS1 Overexpression on Solanesol Content, Plant Growth, Photosynthesis, and Metabolome of Nicotiana tabacum.

Nicotiana tabacum solanesyl diphosphate synthase 1 (NtSPS1) is the key enzyme in solanesol biosynthesis. However, changes in the solanesol content, plant growth, photosynthesis, and metabolome of tobacco plants after NtSPS1 overexpression (OE) have not been previously reported. In the present study, these parameters, as well as photosynthetic gas exchange, chlorophyll content, and chlorophyll fluorescence parameters, were compared between NtSPS1 OE and wild type (WT) lines of tobacco. As expected, NtSPS1 OE significantly increased solanesol content in tobacco leaves. Although NtSPS1 OE significantly increased leaf growth, photosynthesis, and chlorophyll content, the chlorophyll fluorescence parameters in the leaves of the NtSPS1 OE lines were only slightly higher than those in the WT leaves. Furthermore, NtSPS1 OE resulted in 64 differential metabolites, including 30 up-regulated and 34 down-regulated metabolites, between the OE and WT leaves. Pathway enrichment analysis of these differential metabolites identified differentially enriched pathways between the OE and WT leaves, e.g., carbon fixation in photosynthetic organisms. The maximum carboxylation rate of RuBisCO and the maximum rate of RuBP regeneration were also elevated in the NtSPS1 OE line. To our knowledge, this is the first study to confirm the role of NtSPS1 in solanesol biosynthesis and its possible functional mechanisms in tobacco.

Dynamics of antioxidant activities, metabolites, phenolic acids, flavonoids, and phenolic biosynthetic genes in germinating Chinese wild rice (Zizania latifolia).

In this study, the antioxidant activity of germinating Chinese wild rice was found to decline initially, after which it increased. The largest difference in antioxidant activity was observed between the 36-h (G36) and the 120-h germination (G120) stage. We further assessed the dynamic changes in metabolites, phenolic acids, flavonoids, and phenolic biosynthetic genes in germinating Chinese wild rice. Ultra-high performance liquid chromatography-triple quadrupole mass spectrometry revealed that 315 metabolites were up-regulated and 28 were down-regulated between G36 and G120. Levels of p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillin, p-coumaric acid, ferulic acid, and epigallocatechin increased significantly during germination. Gene expression of four phenylalanine ammonia-lyases, one 4-coumarate-CoA ligase, one cinnamoyl-CoA reductase, two cinnamyl alcohol dehydrogenases, one chalcone synthase, and one chalcone isomerase was significantly higher at G120 than at G36 and promoted phenolics accumulation. This study elucidated the biochemical mechanisms involved in antioxidant activity and phenolic profile changes during Chinese wild rice germination.

Chemical composition, sensory properties and bioactivities of Castanopsis lamontii buds and mature leaves.

Castanopsis lamontii is used as functional herbal tea in southwest China. Usually, only buds rather than mature leaves are applied. To figure out whether mature leaves were suitable for producing herbal tea, chemical composition, sensory properties and bioactivities of Castanopsis lamontii bud infusion (CLB) and mature leaf infusion (CLM) were investigated. According to the results, CLB and CLM had similar non-volatile composition, but in different proportion. Meanwhile, CLB contained more types of volatiles than CLM, leading to distinguishable volatile profiles between them. Sensory assessment showed that CLB had sweet aftertaste and floral aroma. CLM tasted astringent and smelled grassy. Bioactivity evaluation indicated that CLB exhibited higher activities in scavenging free radicals and suppressing lipopolysaccharide-induced inflammation. Taken together, CLB had better overall acceptability in sensory quality and higher bioactivity, implying that Castanopsis lamontii buds were more suitable for producing herbal tea.

Extraction Optimization, Structural Characterization, and Anticoagulant Activity of Acidic Polysaccharides from Auricularia auricula-judae.

To explore Auricularia auricula-judae polysaccharides (AAP) as natural anticoagulants for application in the functional food industry, ultrasound assisted extraction (UAE) was optimized for the extraction of AAP by using a response surface methodology (RSM). The maximum extraction yield of crude AAP (14.74 mg/g) was obtained at the optimized extraction parameters as follows: Extraction temperature (74 °C), extraction time (27 min), the ratio of liquid to raw material (103 mL/g), and ultrasound power (198 W). Furthermore, the acidic AAP (aAAP) was precipitated with cetyltrimethylammonium bromide (CTAB) from crude AAP (cAAP). aAAP was further purified using ion exchange chromatography with a DEAE Purose 6 Fast Flow column to obtain aAAP-1. Additionally, according to the HPLC analysis, the aAAP-1 was mainly composed of mannose, glucuronic acid, glucose, galactose, and xylose, with a molar ratio of 80.63:9.88:2.25:1:31.13. Moreover, the results of the activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) indicated aAAP-1 had anticoagulant activity, which was a synergic anticoagulant activity by the endogenous and exogenous pathway.

iTRAQ-based proteomic analysis reveals the accumulation of bioactive compounds in Chinese wild rice (Zizania latifolia) during germination.

Polyphenols and γ-aminobutyric acid (GABA) accumulate during seed germination, but the mechanisms involved are poorly understood. The objective of this study was to elucidate the accumulation of these bioactive compounds in Chinese wild rice during germination. The greatest differences in the phenolic content were at 36-h (G36) and 120-h germination (G120) stages. An iTRAQ-based proteomic analysis revealed 7031 proteins, and a comparison of the G120 and G36 stages revealed 956 upregulated and 188 downregulated proteins. The KEGG analysis revealed significant protein enrichment in the "metabolic pathways", "biosynthesis of secondary metabolites" and "phenylpropanoid biosynthesis". Four phenylalanine ammonia-lyases, one 4-coumarate-CoA ligase, one cinnamoyl-CoA reductase, two cinnamyl alcohol dehydrogenases, and four glutamate decarboxylases exhibited higher expression at the G120 than at the G36 stage and promoted phenolics and GABA accumulation. This study revealed bioactive compound accumulation in germinating Chinese wild rice, and the finding may help develop functional foods derived from this cereal.

Lasiodiplodia theobromae (Pat.) Griff. & Maubl. reduced energy status and ATPase activity and its relation to disease development and pericarp browning of harvested longan fruit.

This study aimed to investigate the effects of Lasiodiplodia theobromae (Pat.) Griff. & Maubl (L. theobromae) inoculation on the energy status and activity of adenosine triphosphatase (ATPase) during L. theobromae-induced disease development and pericarp browning of harvested 'Fuyan' longan (Dimocarpus longan Lour. cv. Fuyan) fruit. The results showed that, compared to the control longans, L. theobromae-inoculated longans displayed higher indices of fruit disease and pericarp browning, lower pericarp ATP and ADP contents, higher AMP content, lower level of energy charge, as well as lower activities of Ca2+-ATPase, Mg2+-ATPase and H+-ATPase in membranes of plasma, vacuole, and mitochondria. These results indicated that the infection of L. theobromae reduced energy status and ATPase activities, caused ions disorder, damaged the integrity and function of the cell and organelles including vacuole and mitochondria in pericarp of longan fruit, which contributed to L. theobromae-promoted disease development and pericarp browning of harvested longan fruit during storage.

A comparative UHPLC-QqQ-MS-based metabolomics approach for evaluating Chinese and North American wild rice.

Wild rice (Zizania spp.) is considered by many consumers to be a health-promoting food. The perennial Z. latifolia (native to Asia) and annual Z. palustris (native to North America) are crops to produce Chinese and North American wild rice, respectively. In this study, we compare the metabolomes of the two species using a UHPLC-QqQ-MS-based metabolomics approach. In total, 672 metabolites were identified; of those, 357 showed differential expression (160 up-regulated versus 197 down-regulated). Metabolic pathway analysis of these differential metabolites showed a significant enrichment of the "Phenylpropanoid biosynthesis" pathway. A hierarchical cluster analysis of differential metabolites of the two species showed a clear grouping pattern in which the relative contents of five anthocyanins and four catechin derivatives differed significantly between the two groups. This study provides reference values for isolation and identification of functional compounds from wild rice and for research and development of functional foods from the two species.

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.

The microstructure of starchy food modulates its digestibility.

Starch is the main carbohydrate in human nutrition and shows a range of desired food properties. It has been demonstrated that fast digestion of starchy food can induce many health issues (e.g., hyperglycaemia, diabetes, etc.); therefore, how to modulate its digestion is an interesting topic. Previous studies have revealed that the microstructure and digestibility of starchy food of different botanical origin or from multiple processes are quite different; modulating starch digestion by retaining or altering its microstructure may be effective. In the present review, the current knowledge of the relationship between microstructural changes to starchy food and its digestibility at molecular, cell and tissue, and food processing levels is summarized. New technologies focused on microstructure studies and ways to manipulate food microstructure to modulate starch digestibility are also reviewed. In particular, some insights focusing on the future study of microstructure and the digestibility of starchy food are also suggested.

Recovery of High Value-Added Nutrients from Fruit and Vegetable Industrial Wastewater.

The industrial processing water of fruit and vegetables has raised serious environmental concerns due to the presence of many important bioactive compounds being disposed in the wastewater. Bioactive compounds have great potential for the food industry to optimize their process and to recover these compounds in order to develop value-added products and to reduce environmental impacts. However, to achieve this goal, some challenges need to be addressed such as safety assurance, technology request, product regulations, cost effectiveness, and customer factors. Therefore, this review aims to summarize the recent advances of bioactive compounds recovery and the current challenges in wastewater from fruit and vegetable processing industry, including fruit and beverage, soybean by-products, starch and edible oil industry. Moreover, future direction for novel and green technology of bioactive compounds recovery are discussed, and a prospect of bioactive compounds reuse and sustainable development is proposed.

Rethinking the Mechanism of the Health Benefits of Proanthocyanidins: Absorption, Metabolism, and Interaction with Gut Microbiota.

Proanthocyanidins, as the oligomers or polymers of flavan-3-ol, are widely discovered in plants such as fruits, vegetables, cereals, nuts, and leaves, presenting a major part of dietary polyphenols. Although proanthocyanidins exert several types of bioactivities, such as antioxidant, antimicrobial, cardioprotective, and neuroprotective activity, their exact mechanisms remain unclear. Due to the complexity of the structure of proanthocyanidins, such as their various monomers, different linkages and isomers, investigation of their bioavailability and metabolism is limited, which further hinders the explanation of their bioactivities. Since the large molecular weight and degree of polymerization limit the bioavailability of proanthocyanidins, the major effective site of proanthocyanidins is proposed to be in the gut. Many studies have revealed the effects of proanthocyanidins from different sources on changing the composition of gut microbiota based on in vitro and in vivo models and the bioactivities of their metabolites. However, the metabolic routes of proanthocyanidins by gut microbiota and their mutual interactions are still sparse. Thus, this review summarizes the chemistry, absorption, and metabolic pathways of proanthocyanidins ranging from monomers to polymers, as well as the mutual interactions between proanthocyanidins and gut microbiota, in order to better understand how proanthocyanidins exert their health-promoting functions.

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.