Investigation on the emulsification mechanism in aqueous enzymatic extraction of edible oil from Schizochytrium sp.

BACKGROUND: The interaction between emulsified substances and lipids generates an emulsification system during the extraction of microalgae edible oil by aqueous enzymatic method. This study aimed to resolve the dynamics of interfacial protein adsorption during the extraction of microalgae oil at different enzymatic times and the effect on the stability of the interfacial membrane formed by the proteins based on interfacial effects. RESULTS: At 1.5 h of enzymatic hydrolysis, the molecular weights of the proteins/peptides were all below 35 kD. In addition, the protein-peptide structure was loose, with the lowest number of disulfide bonds, peak surface hydrophobicity, the highest number of residues, and disordered lipid acyl arrangement. At the same time, the physical stability of the emulsion was the lowest, and the interfacial membrane rupture was distinct. On excessive enzymatic hydrolysis (at 3.0 h), a more uniform interfacial membrane was re-formed on the lipid surface. CONCLUSION: Protein is the main emulsifying substance in the emulsification system. The addition of protease affects the stability of the interfacial membrane formed by proteins. In addition, sufficient enzymatic hydrolysis (1.5 h) inhibited emulsification, while excessive enzymatic hydrolysis (3.0 h) promoted emulsification. © 2023 Society of Chemical Industry.

Mechanisms of Biochanin A Alleviating PM2.5 Organic Extracts-Induced EMT of A549 Cells through the PI3K/Akt Pathway.

Epithelial-mesenchymal transition (EMT) is an important step in tumor progression, which enables tumor cells to acquire migration and invasion characteristics. The aim of this study was to investigate the mechanism of biological biochanin A (BCA) in ameliorating fine particulate matter (PM2.5) lung injury. The results showed that PM2.5 could induce spindle-like changes in cell morphology, causing the ability of migration and invasion. However, they were significantly inhibited by BCA treatment (10/20/30 µm). After BCA treatment, the release and transcription of chemokine CXCL12 and its receptor gene CXCR4 were inhibited, and the release of growth inducer TGF-ß1 was significantly reduced. In addition, BCA promoted the transcription of E-cadherin and ß-catenin, inhibiting the expression of N-cadherin, vimentin, and fibronectin, and down-regulated the expression of MMP-2/9. We found that BCA effectively interfered with the PI3K/Akt signaling pathway activated by PM2.5. In conclusion, PM2.5 can induce EMT in lung cancer cells, and BCA may reverse this process by activating the PI3K/Akt signaling pathway.

The interplay between ABA/ethylene and NAC TFs in tomato fruit ripening: a review.

KEY MESSAGE: This review contains functional roles of NAC transcription factors in the transcriptional regulation of ripening in tomato fruit, describes the interplay between ABA/ethylene and NAC TFs in tomato fruit ripening. Fruit ripening is regulated by a complex network of transcription factors (TFs) and genetic regulators in response to endogenous hormones and external signals. Studying the regulation of fruit ripening has important significance for controlling fruit quality, enhancing nutritional value, improving storage conditions and extending shelf-life. Plant-specific NAC (named after no apical meristem (NAM), Arabidopsis transcription activator factor 1/2 (ATAF1/2) and Cup-shaped cotyledon (CUC2)) TFs play essential roles in plant development, ripening and stress responses. In this review, we summarize the recent progress on the regulation of NAC TFs in fruit ripening, discuss the interactions between NAC and other factors in controlling fruit development and ripening, and emphasize how NAC TFs are involved in tomato fruit ripening through the ethylene and abscisic acid (ABA) pathways. The signaling network regulating ripening is complex, and both hormones and individual TFs can affect the status or activity of other network participants, which can alter the overall ripening network regulation, including response signals and fruit ripening. Our review helps in the systematic understanding of the regulation of NAC TFs involved in fruit ripening and provides a basis for the development or establishment of complex ripening regulatory network models.

Different regulatory mechanisms of plant hormones in the ripening of climacteric and non-climacteric fruits: a review.

KEY MESSAGE: This review contains the regulatory mechanisms of plant hormones in the ripening process of climacteric and non-climacteric fruits, interactions between plant hormones and future research directions. The fruit ripening process involves physiological and biochemical changes such as pigment accumulation, softening, aroma and flavor formation. There is a great difference in the ripening process between climacteric fruits and non-climacteric fruits. The ripening of these two types of fruits is affected by endogenous signals and exogenous environments. Endogenous signaling plant hormones play an important regulatory role in fruit ripening. This paper systematically reviews recent progress in the regulation of plant hormones in fruit ripening, including ethylene, abscisic acid, auxin, jasmonic acid (JA), gibberellin, brassinosteroid (BR), salicylic acid (SA) and melatonin. The role of plant hormones in both climacteric and non-climacteric fruits is discussed, with emphasis on the interaction between ethylene and other adjustment factors. Specifically, the research progress and future research directions of JA, SA and BR in fruit ripening are discussed, and the regulatory network between JA and other signaling molecules remains to be further revealed. This study is meant to expand the understanding of the importance of plant hormones, clarify the hormonal regulation network and provide a basis for targeted manipulation of fruit ripening.

Investigation on the mechanisms of biochanin A alleviate PM10-induced acute pulmonary cell injury.

Epidemiological studies have shown that the elevated concentration of particulate matter with aerodynamic diameter less than 10 µm (PM10) is closely related to the increased risk of heart and lung diseases in the population. Natural isoflavone compound biochanin A (BCA) has anti-inflammatory and antioxidant activities, and has efficacy in alleviating lung injury. The objective of this study was to investigate the inhibitory effect of BCA on PM10 induced acute human bronchial epithelial cells injury. The results showed that PM10 decreased intracellular catalase level to 1.19 ± 0.01 nmol/min/mg prot and induce a surge of reactive oxygen species (ROS). It also increased lactate dehydrogenase (LDH) activity by 428.89% and caused the lipid peroxidation phenomenon. PM10 exposure also upregulates the expression of inflammatory cytokines and mediators. However, BCA could interfere with the above changes caused by PM10, inhibit the LDH level to 8.22 ± 0.03 u/mL, and show anti-inflammatory and antioxidant activities. In addition, the phosphatidylinositol 3-kimase (PI3K) /protein kinase B (PKB/Akt) is a key signal pathway in response to PM10 exposure. In this study, PI3K/Akt signaling pathway is seriously affected by PM10 exposure. PI3K/Akt signaling pathway, PI3K, AKT, tensin homolog deleted on chromosome 10 (PTEN), mechanistic target of rapamycin (mTOR) and p53 protein were all inhibited by PM10 exposure, and PI3K/Akt signaling pathway was inactivated. BCA exert anti-damage function by regulating the activation process of PI3K protein, intervening the regulation process of PI3K/Akt by PTEN, and intervening the expression and phosphorylation of downstream Akt protein.

Research advancement and commercialization of microalgae edible oil: a review.

The global food crisis has led to a great deal of attention being given to microalgal oil as a sustainable natural food source. This article provides an overview of the progress and future directions in promoting the commercialization of microalgal edible oils, including microalgal triglyceride accumulation, suitable edible oil culture strategies for high nutritional value, metabolic engineering, production, and downstream technologies. The integration of the production process, biosafety, and the economic sustainability of microalgal oil production are analyzed for their critical roles in the commercialization of microalgal edible oil to provide a theoretical and scientific basis for the comprehensive development and utilization of microalgal edible oil. © 2021 Society of Chemical Industry.

Physiological and metabolic analysis of winter jujube after postharvest treatment with calcium chloride and a composite film.

BACKGROUND: Ziziphus jujuba Miller cv. Dongzao is extremely susceptible to reddening, browning, nutritional loss, and perishability after harvest. In this study, we evaluated the mechanisms of calcium chloride and chitosan/nano-silica composite film treatments on the quality, especially in reddening, by physiological and metabolomic assays. RESULTS: The treatment delayed the decline of phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), and chalcone isomerase (CHI) activities. Meanwhile, the treated groups retarded the increases in anthocyanin and quercetin contents by inhibiting the gene expressions of flavonol synthase (ZjFLS), dihydroflavonol 4-reductase (ZjDFR), and anthocyanidin synthase (ZjANS), while promoting leucoanthocyanidin reductase (ZjLAR) expression, which leads to retardation of fruit reddening. Anthocyanins were found to be responsible for post-harvest winter jujube reddening through principal component analysis. Results from the technique for order preference by similarity to an ideal solution indicated that the treated group delayed the decline of the quality of 'Dongzao' and extended its shelf life. CONCLUSION: The treatment induced the heightening of flavonoids metabolism. They enhanced the nutritional value and the ability to resist stress by delaying the decline of PAL, CHS, and CHI activities. Meanwhile, the treated groups retarded the increase in anthocyanin and quercetin contents by inhibiting the gene expressions of ZjFLS, ZjDFR, and ZjANS and promoting ZjLAR expression, which leads to retardation of fruit reddening. Anthocyanins are responsible for post-harvest winter jujube reddening. Coating treatment effectively delayed the decline of winter jujube quality. © 2020 Society of Chemical Industry.

Amelioration of PM2.5-induced lung toxicity in rats by nutritional supplementation with biochanin A.

Epidemiological studies have shown that particulate matter with an aerodynamic diameter less than 2.5 µm (PM2.5) is closely associated with human health issues, especially pulmonary diseases such as chronic obstructive pulmonary disease (COPD), asthma and lung cancer. In this study, particles were characterized by scanning electron microscopy (SEM), microbeam energy-dispersive X-ray spectroscopy (EDS), inductively coupled plasma mass spectrometry (ICP-MS) and high-performance liquid chromatography (HPLC). A rat model of PM2.5 exposure was established by nonsurgical intratracheal instillation, and the effects of biochanin A (BCA) treatment were examined. BCA showed a protective effect; it reduced PM2.5-induced apoptosis and the production of proinflammatory factors, such as tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), interleukin-6 (IL-6), and the chemokine interleukin-8 (IL-8), as measured using ELISA. These effects were accompanied by increases in the levels of antioxidant enzymes and decreases in the levels of malondialdehyde (MDA), lactate dehydrogenase (LDH) and alkaline phosphatase (AKP). Furthermore, isobaric tag for relative and absolute quantitation (iTRAQ)-based analytical techniques and bioinformatics tools were used to identify putative biomarkers, including XRCC1, MP2K5, IGJ, and F1LQ12, and the results were verified by Western blot analysis. In conclusion, our findings have scientific significance for the application of flavonoids in preventive and therapeutic strategies for PM2.5-associated pulmonary diseases and for the promotion of human health.

Methyl jasmonate induces the resistance of postharvest blueberry to gray mold caused by Botrytis cinerea.

BACKGROUND: The effects of postharvest methyl jasmonate (MeJA) treatment (50 µmol L-1 ) on the control of gray mold caused by Botrytis cinerea in blueberry fruit were evaluated by analyzing (i) the levels of disease resistance signals; (ii) the activity of enzymes involved in antioxidant system, disease resistance and phenylpropanoid pathway, and (iii) the secondary metabolite content. RESULTS: The results indicated that MeJA treatment significantly restrained the development of gray mold decay in blueberries. The treatment induced a nitric oxide (NO) burst and increased the endogenous hydrogen peroxide (H2 O2 ) content in the earlier period of storage. The enhanced NO and H2 O2 generation by MeJA treatment might serve as a signal to induce resistance against B. cinerea infection. Furthermore, in inoculated fruit, MeJA treatment significantly promoted antioxidant enzymes and defense-related enzyme activity, which included superoxide dismutase, catalase, ascorbate peroxidase, chitinase, and ß-1,3-glucanase, and the degree of membrane lipid peroxidation was reduced. The MeJA treatment enhanced the phenylpropanoid pathway by provoking phenylalanine ammonialyase, cinnamate 4-hydroxylase, and 4-coumarate CoA ligase activity, which was accompanied by elevated levels of phenolics and flavonoids in blueberry fruit. CONCLUSION: These results suggested that MeJA could induce the disease resistance of blueberries against B. cinerea by regulating the antioxidant enzymes, defense-related enzymes, and the phenylpropanoid pathway through the activation of signaling molecules.

Effect of Ginkgo biloba seed exopleura extract and chitosan coating on the postharvest quality of ginkgo seed.

BACKGROUND: The effects of Ginkgo biloba seed exopleura extract (GSEE) and chitosan (CH) coating on the preservation of ginkgo seeds were investigated. RESULTS: Results showed that CH could alleviate the decay rate, and that CH combined with GSEE (CH-GSEE) treatment further inhibited the development of seed decay due to the additional antifungal activity of GSEE. The nutrient contents, including water, starch and soluble protein, were maintained by both CH-GSEE and CH treatments. CH-GSEE treatment led to better restriction on oxidative stress by decreasing superoxide anion production rate, membrane permeability, malondialdehyde content, respiration rate and ethylene production rate. The antioxidant enzyme activities of peroxidase, superoxide dismutase and catalase in ginkgo seeds were maintained by treatment with CH-GSEE at a higher level. These results were consistent with the enhanced visual appearance, qualities and storability of the CH-GSEE-treated seeds. Principal component analysis provided a global view of the internal relations of the ginkgo seeds with different treatments. CONCLUSIONS: The postharvest qualities of CH-GSEE-treated seeds were better than those of other treatment groups. Therefore, CH-GSEE is an effective and alternative way for inhibiting decay, maintaining quality and extending the postharvest life of ginkgo seeds. © 2018 Society of Chemical Industry.

NAC transcription factors play an important role in ethylene biosynthesis, reception and signaling of tomato fruit ripening.

NAC proteins comprise a large family of transcription factors that play important roles in diverse physiological processes during development. To explore the role of NAC transcription factors in the ripening of fruits, we predicted the secondary and tertiary structure as well as regulative function of the SNAC4 (SlNAC48, Accession number: NM 001279348.2) and SNAC9 (SlNAC19, Accession number: XM 004236996.2) transcription factors in tomato. We found that the tertiary structure of SNAC9 was similar to that of ATNAP, which played an important role in the fruit senescence and was required for ethylene stimulation. Likewise, the bio-function prediction results indicated that SNAC4 and SNAC9 participated in various plant hormone signaling and senescence processes. More information about SNACs was obtained by the application of VIGS (virus-induced gene silencing). The silencing of SNAC4 and SNAC9 dramatically repressed the LeACS2, LeACS4 and LeACO1 expression, which consequently led to the inhibition of the ripening process. The silencing of SNACs down-regulated the mRNA levels of the ethylene perception genes and, at the same time, suppressed the expression of ethylene signaling-related genes except for LeERF2 which was induced by the silencing of SNAC4. The expressions of LeRIN were different in two silenced fruits. In addition, the silencing of SNAC4 reduced its mRNA level, while the silencing of SNAC9 induced its expression. Furthermore, the silencing of LeACS4, LeACO1 and LeERF2 reduced the expression of SNAC4 and SNAC9, while the silencing of NR induced the expression of all of them. In particular, these results indicate that SNAC transcription factors bind to the promoter of the ethylene synthesis genes in vitro. This experimental evidence demonstrates that SNAC4 and SNAC9 could positively regulate the tomato fruit ripening process by functioning upstream of ethylene synthesis genes. These outcomes will be helpful to provide a theoretical foundation for further exploring the tomato fruit ripening and senescence mechanism.

Structure Identification of Triterpene from the Mushroom Pleurotus eryngii with Inhibitory Effects Against Breast Cancer.

Breast cancer is the leading cause of death among women, with approximately 1 million diagnoses annually. Triterpenoids, which have cancer preventive or anti-tumour efficacy towards various tumour cells, may play a role in breast cancer prevention. In our previous study, an acetic ether (EtOAc) fraction from the sporocarp of the edible mushroom Pleurotus eryngii (P. eryngii) exhibited significant tumour cell growth inhibition both in vitro and in vivo. In this study, three pentacyclic triterpenoid compounds (1-3) were isolated from EtOAc extracts using chromatographic separation and were identified using nuclear magnetic resonance (NMR) and mass spectrometry (MS). The compounds were 2, 3, 6, 23-tetrahydroxy-urs-12-en-28 oic acid (1), 2,3,23-trihydroxy-urs-12-en-28 oic acid (2) and lupeol (3). All three purified triterpenes showed significant inhibitory activity against breast cancer MCF-7 cell lines in vitro, with the greatest activity exhibited by compound 1, followed by compound 2 and 3. The IC(50) values were 15.71, 48 and 66.89 µM, respectively. Our study may help elucidate the health benefits of P. eryngii mushroom consumption.

A tolerant lactic acid bacteria, Lactobacillus paracasei, and its immunoregulatory function.

The aim of the present investigation was to isolate a probiotic strain from 23 samples of yurts cheese and 21 samples of kumiss (collected from scattered households in Xinjiang and Inner Mongolia), and from eN-Lac Capsules, a health-promoting product. The isolates were subjected to biochemical characterization analysis and were tested for tolerance to low pH, sodium salt, bile salt, pepsin, and trypsin. 16S DNA sequence analysis was conducted to identify the strain. The possible dose-dependent role of strain LP2 in immunomodulation was investigated using the ICR mouse model (from the Institute of Cancer Research). Daily, we conducted clinical observations, a carbon clearance test, a spleen lymphocyte proliferation test, and measurements of body mass and lymphoid organ index. Natural killer cell activity and delayed-type hypersensitivity reaction were determined. The results showed that 3 selected strains (LP2, LP4, and LP9) had high tolerance to low pH, sodium chloride, and bile salt and were not significantly different from Lactobacillus paracasei in terms of morphology, colony, and biochemistry characterizations. A further tolerance test showed that LP2 had the highest survival rate (90%) under the conditions of pH 3.0, 0.3% bile salt, 10 mg/mL pepsin, and 10 mg/mL trypsin for 24 h. The sequence heterogeneities within the 16S rDNA genes molecularly elucidated that the LP2 belongs to the L. paracasei family, on the basis of a homology of 99.6%. A significant enhanced footpad swelling reaction and natural killer cell activity in the middle-dose (10(8) cfu/mL) and the high-dose (10(9) cfu/mL) groups were observed but without obvious dose dependence (P < 0.05). Lymphocyte proliferation was also increased significantly in a dose-dependent manner (P < 0.01) compared with that of the control group, indicating a positive immunoregulatory effect.

Progress on the mechanism of natural products alleviating androgenetic alopecia.

Androgenetic alopecia (AGA) has become a widespread problem that leads to considerable impairment of the psyche and daily life. The currently approved medications for the treatment of AGA are associated with significant adverse effects, high costs, and prolonged treatment duration. Therefore, natural products are being considered as possible complementary or alternative treatments. This review aims to enhance comprehension of the mechanisms by which natural products treat AGA. To achieve this, pertinent studies were gathered and subjected to analysis. In addition, the therapeutic mechanisms associated with these natural products were organized and summarized. These include the direct modulation of signaling pathways such as the Wnt/ß-catenin pathway, the PI3K/AKT pathway, and the BMP pathway. Additionally, they exert effects on cytokine secretion, anti-inflammatory, and antioxidant capabilities, as well as apoptosis and autophagy. Furthermore, the review briefly discusses the relationship between signaling pathways and autophagy and apoptosis in the context of AGA, systematically presents the mechanisms of action of existing natural products, and analyzes the potential therapeutic targets based on the active components of these products. The aim is to provide a theoretical basis for the development of pharmaceuticals, nutraceuticals, or dietary supplements.

Maintaining quality of postharvest green pepper fruit using melatonin by regulating membrane lipid metabolism and enhancing antioxidant capacity.

Green pepper quality often deteriorates during storage because of membrane lipid damage and oxidative stress. This study investigated the effects of exogenous melatonin (MT) on green pepper storage quality, membrane lipids, and antioxidant metabolism. The results showed that MT increased the activities of superoxide dismutase, catalase, ascorbate peroxidase, peroxidase, monodehydroascorbate reductase, and dehydroascorbate reductase in green peppers compared to the control group. It upregulated expression of multiple enzymes; reduced accumulation of reactive oxygen species such as dehydroascorbic acid, H2O2, and O2.-; and maintained high ascorbic acid, glutathione, coenzyme II, and nicotinamide adenine dinucleotide while reducing oxidized glutathione levels. In addition, MT decreased lipoxygenase and phospholipase D activities, downregulated ReLOX and RePLD expression, and delayed the degradation of phosphatidylcholine, phosphatidylethanolamine, and oleic, linoleic, and linolenic acids in green peppers. These results suggest that MT helps to improve the chilling injury and quality of green peppers and extends shelf life.

The characterization of antimicrobial nanocomposites based on chitosan, cinnamon essential oil, and TiO2 for fruits preservation.

The freshness and safety of fruits have always been crucial issues in the development of the industry. However, the existing fresh-keeping methods have limited effect, meanwhile, the preservation mechanism of different materials. In this study, Cinnamon essential oil (CEO), TiO2, and chitosan (CS) were compounded to prepare safe and renewable nanocomposites (CS-T-C) for fruit preservation. The results showed that CEO mainly destroyed the bacterial cell wall through penetration, while TiO2 is through destruction. The strawberry coated with CS-T-C showed better hardness, lower weight loss and mildew rate, and the shelf-life at 20℃ was extended for four days compared with the control. And all four nanocomposites were not cytotoxic. In summary, nanocomposites can deal with many problems through different mechanisms to maximize the fresh-keeping effect, and the nanocomposites developed in this work might be a good choice for fruit preservation.

Effect of nanopackaging on the quality of edible mushrooms and its action mechanism: A review.

With higher demands for food packaging and the development of nanotechnology, nanopackaging is becoming a research hotspot in the field of food packaging because of its superb preservation effect, and it can effectively resist oxidation and regulates energy metabolism to maintain the quality and prolong the shelf life of mushrooms. Furthermore, under the background of SARS-CoV-2 pandemic, nanomaterials could be a potential tool to prevent virus transmission because of their excellent antiviral activities. However, the investigation and application of nanopackaging are facing many challenges including costs, environmental pollution, poor in-depth genetic research for mechanisms and so on. This article reviews the preservation effect and mechanisms of nanopackaging on the quality of mushrooms and discusses the trends and challenges of using these materials in food packaging technologies with the focus on nanotechnology and based on recent studies.

Rheological properties, gel properties and 3D printing performance of soy protein isolate gel inks added with different types of apricot polysaccharides.

A soybean protein isolate (SPI)-apricot polysaccharide gel with hypolipidemic activity that can be used for 3D printing was prepared and the mechanism of its gel formation was studied in this work. The results demonstrated that adding apricot polysaccharide to SPI could effectively improve the bound water content, viscoelastic properties and rheological properties of the gels. Low-field NMR, FT-IR spectroscopy and surface hydrophobicity confirmed that the interactions between SPI and apricot polysaccharide were mainly realized by electrostatic interactions, hydrophobic and hydrogen bonding. Furthermore, adding modified polysaccharide treated by ultrasonic-assisted Fenton method to SPI on the basis of low-concentration apricot polysaccharide contributed to improving the 3D printing accuracy and stability of the gel. Consequently, the gel formed by adding apricot polysaccharide (0.5 %, m/v) and modified polysaccharide (0.1 %, m/v) to SPI had the best hypolipidemic activity (the binding rate of sodium taurocholate and sodium glycocholate were 75.33 % and 72.86 %, respectively) and 3D printing characteristics.

Glycine betaine inhibits postharvest softening and quality decline of winter jujube fruit by regulating energy and antioxidant metabolism.

Winter jujube fruit easily softens after harvest. To investigate the effects of glycine betaine (N,N,N-trimethylglycine; GB) treatment on the quality of postharvest jujubes, fresh winter jujubes (Zizyphus jujuba Mill. cv. Dongzao) were immersed in 20 mmol·L-1 GB for 20 min. The results showed that GB application can effectively maintain cell wall component content by restraining gene expression and enzyme activities, including PG, CX, PME and ß-Glu. Meanwhile, the activities of antioxidant enzymes (APX, CAT, SOD, POD) and the contents of nonenzymatic antioxidants (MDA, H2O2, ASA, GSH) were enhanced in treated jujubes, thereby reducing the content of ROS. In addition, energy metabolism enzyme activities (H+-ATPase, Ca2+-ATPase, SDH and CCO) and gene expression were also significantly increased, thus maintaining higher energy levels (ATP, ADP, AMP and EC). In summary, GB enhances ATP biosynthesis by increasing energy metabolism. It offers essential energy for the antioxidant metabolism, thus retarding the softening of postharvest jujubes.

CRISPR/Cas9-mediated SNAC9 mutants reveal the positive regulation of tomato ripening by SNAC9 and the mechanism of carotenoid metabolism regulation.

NAC transcriptional regulators are crucial for tomato ripening. Virus-induced gene silencing (VIGS) of SNAC9 (SlNAC19, Gene ID: 101248665) affects tomato ripening, and SNAC9 is involved in ethylene and abscisic acid (ABA) metabolic pathways. However, the function of SNAC9 in pigment metabolism in tomatoes remains unclear. This work seeks to discover the mechanism of SNAC9 involvement in pigment metabolism during tomato ripening by establishing a SNAC9 knockout model using CRISPR/Cas9 technology. The results indicated that fruit ripening was delayed in knockout (KO) mutants, and SNAC9 mutation significantly affected carotenoid metabolism. The chlorophyll (Chl) degradation rate, total carotenoid content, and lycopene content decreased significantly in the mutants. The transformation rate of chloroplasts to chromoplasts in mutants was slower, which was related to the carotenoid content. Furthermore, SNAC9 changed the expression of critical genes (PSY1, PDS, CRTISO, Z-ISO, SGR1, DXS2, LCYE, LCYB, and CrtR-b2) involved in pigment metabolism in tomato ripening. SNAC9 knockout also altered the expression levels of critical genes involved in the biosynthesis of ethylene and ABA. Accordingly, SNAC9 regulated carotenoid metabolism by directly regulating PSY1, DXS2, SGR1, and CrtR-b2. This research provides a foundation for developing the tomato ripening network and precise tomato ripening regulation.