The longan industry produces a large amount of byproducts such as pericarp and seed, resulting in environmental pollution and resource wastage. The present study was performed to systematically evaluate functional components, i.e., polyphenols (phenolics and flavonoids) and alkaloids, in longan byproducts and their bioactivities, including antioxidant activities, nitrite scavenging activities in simulated gastric fluid and anti-hyperglycemic activities in vitro. Total phenolic and total flavonoid contents in pericarp were slightly higher than those in seeds, but seeds possessed higher alkaloid content than pericarp. Four polyphenolic substances, i.e., gallic acid, ethyl gallate, corilagin and ellagic acid, were identified and quantified using high-performance liquid chromatography. Among these polyphenolic components, corilagin was the major one in both pericarp and seed. Alkaloid extract in seed showed the highest DPPH radical scavenging activity and oxygen radical absorbance capacity. Nitrite scavenging activities were improved with extract concentration and reaction time increasing. Flavonoids in seed and alkaloids in pericarp had potential to be developed as anti-hyperglycemic agents. The research result was a good reference for exploring longan byproducts into various valuable health-care products.

There have been few studies dealing with chemical elucidation and pharmacological potentials of water-soluble polysaccharides from jasmine tea, limiting their use in functional foods. In this study, water-soluble polysaccharides (named as JSP) were extracted from Jasminum sambac (L.) Aiton tea and fractionated to afford two sub-fractions (JSP-1 and JSP-2). The main structural characteristics of novel JSP sub-fractions were determined by high performance gel permeation chromatography, ultra-performance liquid chromatography-tandem mass spectrometry, Fourier transform infrared, and nuclear magnetic resonance analysis. Physiologically, the abilities of JSP-1 and JSP-2 to reduce ferric ions, scavenge DPPH and hydroxyl radicals, as well as protect islet cells were confirmed in vitro. JSP-1 exhibited better antioxidant and hypoglycemic activities than JSP-2. The molecular weights of JSP-1 and JSP-2 were 18.4 kDa and 14.1 kDa, respectively. JSP-1 was made up of glucose, galactose, rhamnose, xylose, arabinose, and galacturonic acid with molar ratios 1.14:4.69:1.00:9.92:13.79:4.09, whereas JSP-2 with a triple helical structure was composed of galactose, rhamnose, xylose, arabinose, and galacturonic acid as 3.80:1.00:8.27:11.85:5.05 of molar ratios. JSP-1 contains →1)-α-Galƒ-(3→, →1)-α-Galƒ-(2→, →1)-α-Araƒ-(5→, →1)-α-Araƒ-(3→, →1)-α-Araƒ-(3,5→, →1)-β-Xylp-(2→ and →1)-β-Xylp-(3→ residues in the backbone. These results open up new pharmacological prospects for the water-soluble polysaccharides extracted from jasmine tea.

This study aimed to develop functional fruit wines using whole fruit, pulp, and peels from green bananas. The boiled banana homogenates were mixed with cane sugar before wine fermentation. Quality parameters, phenolic compounds, flavor components, and antioxidative properties of the green banana peel wine (GBPW), green banana pulp wine (GBMW), and whole banana wine (GBW) were determined. High-performance liquid chromatography was used to determine the phytochemical compounds in three wines, and the flavor components were further analyzed using headspace solid-phase microextraction combined with gas chromatography–mass spectrometry. The flavor components and in vitro antioxidant activities were, respectively, determined using the relative odor activity value and the orthogonal projections on latent structure discrimination analysis (OPLS-DA). In vitro antioxidative capacities for these wines were evaluated using antioxidant chemical assays and cell culture methods. The total phenolic and total tannin content of the GBPW, GBMW, and GBW showed reducing trends with increasing fermentation days, whereas the total flavonoid content of the wine samples exhibited downward trends. The antioxidant capacities of the three wine samples were higher than those of the raw fruit samples, except for the metal chelation rate (%). Additionally, the main flavor component in the wine samples was 3-methyl-1-butanol. Its percentages in the GBPW, GBMW, and GBW were 72.02%, 54.04%, and 76.49%, respectively. The OPLS-DA results indicated that the three wines presented significantly different antioxidant activities. The cell-culture-based antioxidant analysis showed that these wine samples had protective effects against the oxidative stress of the 3T3-L1 preadipocytes induced by hydrogen peroxide. This study provided a theoretical basis for defining the antioxidant characteristics of banana wines and expanding novel channels for using banana peels to develop nutraceuticals.

Polysaccharides from hemp seeds exhibit antioxidant activities in vitro and in vivo. However, crude polysaccharide quality is often low owing to the presence of fibres and pigment impurities, which are difficult to eliminate in the hemp seed shell. In this study, crude polysaccharides from hemp kernels (HKP) were obtained by hot water extraction and separated by membrane ultrafiltration into eight fractions with different molecular weights. Total antioxidant capacity and free radical scavenging (DPPH) assays were performed to evaluate the antioxidant activities of HKP and the fractions in vitro. The structural characteristics of HKP were determined using various analytical techniques. The Fe³⁺-reducing power of HKP was 7.65 ± 0.22 μmol/g, and HKP possessed the highest DPPH radical-scavenging rates (94.30 ± 2.27%), similar to 5 mg/mL Vitamin C (Vc), which had a rate of 95%. The HKP was an acidic polysaccharide with a low molecular weight (4.21 ± 0.12 kDa). The monosaccharide composition indicated that HKP primarily comprised mannose, ribose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, and fucose in a molar ratio of 0.96:1.95:8.27:0.98:9.46:1.69:6.10:2.82. The molar mass of HKP was distributed widely in a triple helical conformation. This study provides a scientific basis for further research on the use of hemp polysaccharides.

Passion fruit ( Passiflora edulia Sims ), an important tropical and sub-tropical species, is classified as a respiration climacteric fruit, the quality deteriorates rapidly after harvest. To reveal the mechanisms involved in ripening and rapidly fruit senescence, the phytochemical characteristics and RNA sequencing were conducted in the purple passion fruits with different (1-MCP and PF) treatment. Comprehensive functional annotation and KEGG enrichment analysis showed that the starch and sucrose metabolism, plant hormone signal transduction, phenylpropanoid biosynthesis, flavonid biosynthesis, carotenoid biosynthesis were involved in fruit ripening. Applying with PF and 1-MCP significantly affected transcript levels of passion fruit after harvest storage. A large number of differently expressed unigenes (DEGs) were identified significantly enrichen in starch and sucrose metabolism, plant hormone signal transduction and phenylpropanoid biosynthesis at postharvest stage. The preservative film (PF) and 1-Methylcyclopropene (1-MCP) treatments increased superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) gene expression and enzyme activities, accelerated the lignin accumulation, decline β-galactosidase (β-Gal), polygalacturonase (PG) and cellulose activities and gene expression to delay cell wall degradation during fruit senescence. The RNA sequencing data of cell wall metabolism and hormone signal transduction pathway related unigenes were verified by RT-qPCR. The results indicated that the cell wall metabolism and hormone signal pathways were notably related to passion fruit ripening. PF and 1-MCP treatment might inhibited ethylene signaling and regulated cell wall metabolism pathways to inhibited cell wall degradation. Our results reveal ripening and senescence related networks during passion fruit ripening, which can provide a foundation for understanding the molecular mechanisms underlying PF and 1-MCP treatment on fruit ripening.

This study aimed to screen out polysaccharides with the ability to activate NK cells. Ten polysaccharides (OP) were isolated from orah mandarin (Citrus reticulata cv. Orah) peel using hot-water extraction combined with the alcohol precipitation method and the ultrafiltration-membrane separation method. After measuring the effects of 10 OPs on NK-92MI cell proliferation and cytotoxicity, it was found that the polysaccharide OP5 had the highest activity in vitro. OP5 can significantly promote the proliferation of and increase the gene expression of perforin, granzyme B and IFN-γ in NK-92MI cells. Its molecular weight was between 50 and 70 kDa. The identification results of monosaccharide composition indicated that OP5 was composed of arabinose (31.52%), galacturonic acid (22.35%), galactose (16.72%), glucose (15.95%), mannose (7.67%), rhamnose (2.39%), fucose (1.41%), xylose (1.30%), glucuronic acid (0.42%) and ribose (0.27%). The sugar ring of the β-configuration was the main, and that of the α-configuration was the auxiliary. These results would provide a foundation for the functional product development of OPs.