Acute Toxicity, Antioxidant, and Antifatigue Activities of Protein-Rich Extract from Oviductus ranae

Polysaccharides from waste Zingiber mioga leaves: Ultrasonic-microwave-assisted extraction, characterization, antioxidant and anticoagulant potentials

Zingiber mioga is a highly economic crop that is used to produce vegetables, spices and herbal pharmaceuticals. Its edible flower bud contributes most to the economic value, but the big leaves were discarded as agricultural waste, which urgently needs to be exploited. In this work, polysaccharides from waste Z. mioga leaves (PWZMLs) were extracted using ultrasonic-microwave-assisted extraction (UMAE). After purification and characterization, the antioxidation and anticoagulation of PWZMLs were evaluated to appraise the potential in cardiovascular protection. Under the liquid-solid ratio of 26: 1 mL/g, after ultrasonication at 495 W for 10 min, followed by microwaving at 490 W for 5 min, the yield of PWZMLs achieved to 6.22 ± 0.14 %, notably higher (P < 0.01) than other methods, and ultrasound contributed more to the yield than microwave. Various analyses confirmed that PWZMLs were negatively charged polysaccharides with galacturonic acid the dominant uronic acid. PWZMLs exerted excellent antioxidant capacity, especially for scavenging 1, 1-diphenyl-2-picrylhydrazyl radical. PWZMLs also elicited promising anticoagulant property, particularly for prolonging activated partial thromboplastin time and lowering fibrinogen, which were almost equivalent to heparin at the same concentration. PWZMLs contained two polysaccharide fractions (199.53 and 275.42 kDa) that could synergistically contribute to the pronounced antioxidant and anticoagulant activities. The PWZMLs extracted with optimized UMAE have great potential in cardiovascular protection.

Microwave-assisted enzymatic extraction brings a notably high yield of polysaccharides from mountain Zizania latifolia

Mountain Zizania latifolia is produced at scale in China, and the edible swollen culm is exported to many countries, but little attention has been paid to its functional components. In this work, microwave-assisted enzymatic extraction (MAEE) is used for the first time to extract polysaccharides from mountain Z. latifolia swollen culm (PMZL). MAEE conditions optimized by Box-Behnken design-response surface methodology were as follows: 2.4% cellulase, microwaving for 6.0 min at 607 W, with a liquid-to-solid ratio of 63:1 ml g^-1 . Under these conditions, a notably high yield of 60.43% ± 1.12% for PMZL was achieved, which was significantly higher (p < 0.01) than from plain-grown varieties. PMZL are naturally occurring sulfated polysaccharide-protein complexes containing 8.46% ± 0.18% proteins and 7.86% ± 0.73% sulfates. PMZL comprises mannose, glucosamine, rhamnose, glucose, galactose, and arabinose at molar ratios of 3.80:2.68:1.00:17.41:5.12:2.91, with a weight-average molecular weight of 1569,219 Da and a number-average molecular weight of 364,088 Da. The surface morphology of PMZL is composed of tightly packed oval particles, and this kind of promising polysaccharides preferentially scavenges reactive nitrogen species. PRACTICAL APPLICATION: Due to global warming, the land available for planting vegetables is likely to expand to higher areas, so greater attention should now be paid to mountain-grown vegetables. This study provides an efficient way to obtain novel polysaccharides from mountain Zizania latifolia using microwave-assisted enzymatic extraction with a remarkably high yield of 60.4%. This promising source of natural carbohydrates has potential uses in pharmaceutical, nutraceutical, functional foods, cosmetics, and functional materials industries.

Synthesis, stability and anti-fatigue activity of selenium nanoparticles stabilized by Lycium barbarum polysaccharides

Lycium barbarum polysaccharides (LBP) with different molecular weights (LBP1, LBP2 and LBP3) of 92,441 Da, 7714 Da, and 3188 Da were used as stabilizers and capping agents to prepare uniformly dispersed selenium nanoparticles (SeNPs), and determined the storage stability. In addition, the anti-fatigue activity of LBP-decorated SeNPs with the best stability (LBP1-SeNPs) was estimated by using forced swimming test. The results showed that LBP1-SeNPs exhibited smaller particle size and more excellent stability than those of LBP2-SeNPs and LBP3-SeNPs when the storage time was extended to 30 days, and the average particle size was maintained at about 105.4 nm. The exhaustion swimming time of all tested dose groups of LBP1-SeNPs was significantly longer than the control group (p < 0.05), and the high-dose group among them was even obviously longer than the positive group (p < 0.05). The results of glycogen, blood urea nitrogen (BUN), blood lactic acid (BLA), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were further confirmed that LBP1-SeNPs could relieve fatigue by increasing the reserve of glycogen, enhancing antioxidant enzyme levels and regulating metabolic mechanism. These results demonstrated that LBP1-SeNPs could be developed as a potential anti-fatigue nutritional supplement.

Antibacterial effects of a polypeptide-enriched extract of Rana chensinensis via the regulation of energy metabolism

The improper usage of antibiotics is known to cause widespread antibiotic resistance. In this study, the antibacterial effects of a polypeptide-enriched extract from the skin of the amphibian Rana chensinensis (RCP) were evaluated against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive bacterium Staphylococcus aureus and the fungus Candida albicans. The mechanisms underlying these effects were also studied, and the minimum inhibitory concentration of RCP was determined for each species. Analyses of the levels of adenosine triphosphates (ATPases), including Na⁺/K⁺-ATPase and Ca²⁺-ATPase, and scanning electron microscopy confirmed that RCP damaged the microbial cell walls and membranes. RCP perturbed microbial metabolism and particularly affected the tricarboxylic acid cycle (TCA), suggesting that this agent downregulated the levels of succinate dehydrogenase, malate dehydrogenase and ATPase activity in cells. Furthermore, RCP caused the leakage of genetic material from all four microbial strains. In conclusion, RCP effectively inhibited the growth of Gram-negative and Gram-positive bacteria and a fungal species by disrupting energy metabolic processes.

Environmental influences on quality features of Oviductus Ranae in the Changbai Mountains

This work studied the influences of environmental factors on the quality features of Oviductus Ranae. Oviductus Ranae is mainly produced in the Changbai Mountains. The samples of Oviductus Ranae were collected from 24 different locations, which covered the main producing areas. The environmental parameters were assessed using a digital raingauge, GPS, a thermometer, and an atmospheric pressure-altimeter. The quality features including expansion degree, ethanol extract, total water, total ash, and five steroid components, of the collected Oviductus Ranae samples were quantified using high-performance liquid chromatography. The results showed that the cholesterol content in the samples collected from the Yanbian Korean region was slightly higher than the others. Samples collected from the Huadian area exhibited much higher contents of 7-hydroxycholesterol and 7-dehydrocholesterol than the rest of the producing areas. The highest content of cholest-4-en-3-one came from the samples collected from Dandong. The contents of 7-keto-cholesterol in samples from different regions were very close. The highest ethanol extract was from the samples in Tonghua. The correlations between the quality features and environmental factors were analyzed by SPSS (version 25.0, SPSS Inc., Chicago, IL, USA). The results showed that the content of cholest-4-en-3-one was related to the annual average temperature. The total water was correlated with the annual precipitation. 7-Hydroxycholesterol and expansion degree were related to the altitude. The results indicated that environmental factors have certain influences on the quality features.

Protective mechanism of 1-methylhydantoin against lung injury induced by paraquat poisoning

Paraquat (PQ), one of the most widely used herbicides worldwide, causes severe toxic effects in humans and animals. 1-methylhydantoin (MH) is an active ingredient of Ranae Oviductus, which has broad pharmacological activities, e.g., eliminating reactive oxygen species and inhibiting inflammation. This study investigated the effects of MH on lung injury induced by PQ. A PQ poisoning model was established by intragastric infusion of PQ (25 mg/kg), and the control group was simultaneously gavaged with the same dose of saline. The MH group was intraperitoneally injected with 100 mg/kg once per day after intragastric infusion of PQ (25 mg/kg) for five consecutive days. All animals were sacrificed on the sixth day, and the lung tissues were dissected for metabolomics analysis. The lactate dehydrogenase (LDH) activity, superoxide dismutase (SOD) activity, TNF-α and malondialdehyde (MDA) content were determined according to the instructions of the detection kit. Compared with that in the control group, the content of LDH, TNF-α and MDA in the lung tissue of the PQ group was significantly higher, and the activity of SOD in the lung tissue was significantly lower (all p<0.05). Compared with that in the control group, the content of LDH, TNF-α and MDA in the MH group was significantly higher, and the activity of SOD was significantly lower (all p<0.05). However, the differences in SOD activity, LDH activity between the PQ and MH groups were not statistically significant (all p > 0.05). There were significant differences in MDA and TNF-α content between the PQ group and MH group (all p<0.05). MH decreased the production of malondialdehyde and TNF-α to protect against the lung injury caused by PQ poisoning, but it had no significant effect on the activity of LDH and SOD. There were significant differences in metabolomics between the MH group and the PQ poisoning group, primarily in bile acid biosynthesis and metabolism of cholesterol, nicotinate, nicotinamide, alanine, aspartate, glutamate, glycine, threonine, serine, phenylalanine and histidine. Therefore, this study highlights that MH has non-invasive mechanisms and may be a promising tool to treat lung injury induced by PQ poisoning.

Traditional Uses, Bioactive Constituents, Biological Functions, and Safety Properties of Oviductus ranae as Functional Foods in China

Oviductus ranae is an animal-based traditional Chinese material widely used as tonics in China for hundreds of years. Various bioactive components are present in OR including proteins, amino acids, steroids, fatty acids, phospholipids, nucleosides, vitamins, hydantoins, and mineral elements. These constituents exert a myriad of biological functions such as immunomodulatory, antioxidant, antifatigue, antiaging, estrogen-like, hepatoprotective, hypolipidemic, antiosteoporotic, antidepressant, antitumor, antitussive, expectorant, anti-inflammatory, and antiasthmatic activities. Unlike other traditional Chinese crude drugs recorded in Chinese Pharmacopoeia, OR is seldom prescribed as medicine but often consumed as nutraceuticals to optimize health. In this review, the traditional uses, bioactive constituents, biological functions, and safety properties of OR as functional foods in China were summarized and discussed. It is expected that this review will provide useful information for anyone who is interested in OR.