天然植物抗氧剂二氢杨梅素抗氧活性影响因素研究

目的:研究天然植物抗氧剂二氢杨梅素的抗氧活性与影响因素的关系。方法:采用丙二醛测定法来评价其抗氧化效果。结果:在食品生产中,添加二氢杨梅素的质量浓度以0.06%为宜;在酸性介质下,二氢杨梅素可发挥抗氧作用,pH为4～5时,抗氧活性最大;不同溶剂对其抗氧活性有一定影响,乙醇对其具有增效作用;二氢杨梅素是一种耐热性很好的抗氧化剂,在200℃下处理2h后不影响其抗氧性能的发挥。结论:二氢杨梅素是一种颇具发展前景的新型抗氧化剂。

植物抗氧剂最近研究概况

植物成分的药理作用与其抗氧化性质密切相关。目前对植物抗氧剂的研究逐年增多,本文对几种植物抗氧剂的研究现状作了简要综述。

类SOD的鉴别及研究进展

本文综述了近年类SOD的研究进展,其内容主要包括类SOD的鉴别、抗氧酶和抗氧剂的抗氧化作用。类SOD的应用研究主要有抗肿瘤作用、免疫作用、抗辐射、抗衰老、抗疲劳等。

Antihymolytic and Antioxidant Effects of Medicinal Plant Capparis spinosa L.

Capparis spinosa L. is a traditionally used plant in Algerian folk medicine to treat asthma, rheumatism and other free radicals related disorders such inflammatory. The present study was designated to study the antioxidant activity of aerial and root parts of Capparis spinosa L.. Total polyphenol content was determined, after extraction with solvents in five subfractions; methanol （CE）, Hexan （HE） chloroform （CHE）, ethyl acetate （EAE） and aqueous extracts （AE）, employing the ＂Prussian blue assay＂. The results showed that EAE containing the highest concentration of phenolic compounds and Flavonoids followed by those of CHE of aerial and root parts, repectively. The antioxidant protective effects of extracts were determined by measuring the erythrocyte membrane resistance to free radical-induced. The results demonstrated that all the extracts exhibited a protective effect against t-BHP induced oxidative damages in human erythrocytes, the most potents wer CEs and CHEs with 86.55%, 85.81%, 74.59%, and 68.70%, for aerial and root parts, respectively, which were more effective than used standards： Quercetin （65.46%） and rutin （59.62%）. In order to more clarify the previous antioxidants activity of the extracts through other mechanisms, the iron chelating ability assays were realized. The results showed that the iron chelating ability of Aerial and root extracts were very considerable; the CE showed an excellent chelating with ICs0 of 0.197 ± 0.031 μM/quercetin equivalent, higher than that used standard EDTA, with approximately 0.34 folds. These results show that Capparis spinosa L. extracts have strong anti-oxidant effects and may have some clinical benefits.

Effects of Plant Extracts with Antioxidant Activities on Male Mule Ducks＇ Performance

Plant extracts with antioxidant activities have effect on male mule ducks performance, and livestock animals have a strong metabolism activity, due to their high production requirements. It can lead to oxidative stress disorders; deteriorate growth performance and even their health. The objective of this study was to assess the effect of a mixture of active ingredients of plant extracts, known for their antioxidant and anti-inflammatory properties, on performances of mule ducks, in rearing and force-feeding period. Then 3,200 day-old mule ducks （MMGxPKL） were separated in 2 groups （negative control and treatment = EL） ×4 replicates per group for the rearing period. Each group received the same feeding program. EL group was supplemented, until the force-feeding period, with a mixture of actives from plants incorporated at 0.5% in the complete feed. At 84 days, the live weight and the feed consumption were measured for each treatment. Blood samples were also taken to measure the activity of two antioxidant enzymes： SOD （superoxide dismutase） and GPx （glutathione peroxidase）. For force-feeding, the ducks were separated among 3 farmers during 12 days. At slaughter, individual measures of breast and liver were conducted. At 84 days, mean live weight for EL group was improved by 3.7% （p 〈 0.001）. Feed conversion ratio was also improved （4.50 versus 4.62）. At slaughter, breast weight was higher for EL group （p 〈 0.01）. A high variability in the results of the activities of antioxidant enzymes was obtained. A decrease in SOD activity in erythrocytes was observed for the EL group （p 〈 0.05）. The results showed that the actives assessed in this study, distributed to ducks during the rearing period, had a beneficial effect on growth performance over that period. The mechanisms of endogenous antioxidant system and inflammatory responses remain to be elucidated.

The Potential Application of Plant Essential Oils/Extracts as Natural Preservatives in Oils during Processing： A Review

The present work summarizes recent investigations carried out about the usage of natural antioxidants in lipid-rich food during processing. Synthetic antioxidants have been used as food additives to retard lipid oxidation and development of off-flavor for over 50 years. However, the literature has expressed safety concerns and health risks （toxic and carcinogenic effects） associated with the use of synthetic antioxidants recently. Natural antioxidative substances from the polyphenols of edible plants are believed to be safer and may provide with additional health benefits and more effective compared to synthetic antioxidants. Due to the fact that natural antioxidants are additives that people mixed with food and consumed for centuries, they are known to be safe by the consumer. Therefore, it is an area worth to investigate due to consumer concerns about health. In the literature, there are many studies showing that the natural antioxidants have important antioxidant effect. Plants （oil seeds, cereals, vegetables, fruits, herb and spices）, compounds from animal source （peptides and amino acids）, enzymes and some microorganisms are important natural antioxidants. Plant extracts have been widely used to retard lipid oxidation in foods during frying and accelerated storage processes. They were found as strong antioxidant sources due to their high contents of phenolic compounds. There are countless studies about natural antioxidants. However, they have not been investigated completely by means of toxicology.

Determination of the Antioxidant, Phytochemical and Antibacterial Profiles of Flowers from Selected Ornamental Plants in Nueva Vizcaya, Philippines

With the increasing interest on natural products discovery, utilization of plant parts which are commonly disregarded is another breakthrough. This study sought to determine the secondary metabolites present, phenolic contents, radical scavenging activities and antibacterial properties of 10 selected ornamental flowers which were Adenium obesum, Allamanda cathartica, Bougainvillea glabra, Catharanthus roseus, Caesalpinia pulcherrima, Heliconia subulata, Ixora coccinea, Mussaenda philippica, Tecoma stans and Torenia fournieri, from Nueva Vizcaya, Philippines. The ethanolic crude extracts were subjected to thin layer chromatography （TLC） phytochemical screening. Total phenolics expressed as mg AAE/g sample were determined through Folin-Ciocalteu method. Radical scavenging activities were measured using DPPH assay. Antibacterial activities were assessed through TLC bioautography. To quantify bacterial susceptibility of C. pulcherrima, MIC and MBC were employed in the ethyl acetate sub-fraction. TLC showed different types of phenolics, alkaloids, essential oils and terpenes. T. fournieri showed the highest total phenolics with 155 mg AAE/g while H. subulatahad showed the lowest with 3.50 mg AAE/g. Measurement of IC59 showed that H. subulata had the highest antioxidant activity followed by T. fournieri with 303 ppm and 320 ppm, respectively. H. subulata having the least amount of total phenolics had greatest radical scavenging activity. This indicates that other than phenolics, other metabolites can pose great antioxidant activities. The antibacterial testing showed that M. philippica, 1. coccinea, 1-1. subulata, C. pulcherrima and A. cathartica were bioactive against Staphylococcus aureus and Escherichia coll. MIC and MBC of C. pulcherrima ethyl acetate sub-fraction is within the range of 2.5-10 mg/mL.

Effects of ferulic acid on antioxidant activity in Angelicae Sinensis Radix, Chuanxiong Rhizoma, and their combination

The present study aimed at exploring different roles of the same compound in different environment, using preparative HPLC, and the significance to investigating bio-active constituents in traditional Chinese medicine （TCM） on the basis of holism. In this study, the depletion of target component ferulic acid （FA） by using preparative HPLC followed by antioxidant activity testing was applied to investigate the roles of FA in Angelicae Sinansis Radix （DG）, Chuanxiong Rhizoma （CX） and their combination （GX）. The antioxidant activity was performed by 1, 1-diphenyl-2-picrylhydrazyl （DPPH） radical-scavenging activity testing. FA was successfully and exclusively depleted from DG, CX, and GX, respectively. By comparing the effects of the samples, it was found that FA was one of the main antioxidant constituents in DG, CX and GX, and the roles of FA were DG 〉 CX 〉 GX. Furthermore, the effects of FA varied at different doses in these herbs. This study provided a reliable and effective approach to clarifying the contribution of same compound in different TCMs to their bio-activities. The role of a constituent in different TCMs might be different, and a component with the same content might have different effects in different chemical environments. Furthermore, this study also suggested the potential utilization of preparative HPLC in the characterization of the roles of multi-ingredients in TCM.

Endophytes from medicinal plants and their potential for producing indole acetic acid, improving seed germination and mitigating oxidative stress

Medicinal plants have been used by marginal communities to treat various ailments. However, the potential of endophytes within these bio-prospective medicinal plants remains unknown. The present study elucidates the endophytic diversity of medicinal plants（Caralluma acutangula, Rhazya stricta, and Moringa peregrina） and the endophyte role in seed growth and oxidative stress. Various organs of medicinal plants yielded ten endophytes, which were identified as Phoma sp.（6 isolates）, Alternaria sp.（2）, Bipolaris sp.（1）, and Cladosporium sp.（1） based on 18 S rD NA sequencing and phylogenetic analysis. The culture filtrates（CFs; 25%, 50%, and 100% concentrations） from these endophytes were tested against the growth of normal and dwarf mutant rice lines. Endophytic CF exhibited dose-dependent growth stimulation and suppression effects. CF（100%） of Phoma sp. significantly increased rice seed germination and growth compared to controls and other endophytes. This growth-promoting effect was due to the presence of indole acetic acid in endophytic CF. The gas chromatography/mass spectrometry（GC/MS） analysis showed the highest indole acetic acid content（（54.31±0.21） μmol/L） in Bipolaris sp. In addition, the isolate of Bipolaris sp. exhibited significantly higher radical scavenging and anti-lipid peroxidation activity than the other isolates. Bipolaris sp. and Phoma sp. also exhibited significantly higher flavonoid and phenolic contents. The medicinal plants exhibited the presence of bio-prospective endophytic strains, which could be used for the improvement of crop growth and the mitigation of oxidative stresses.

Antimelanogenic effects of Inula britannica flower petal extract fermented by Lactobacillus plantarum KCCM 11613P

The inhibitory effects of Lactobacillus plantarum-fermented and non-fermented Inula britannica extracts on the tyrosinase activity were comparatively investigated to examine whether and how they improve the whitening activity, and the contents of total flavonoids and polyphenolics as bioactive compounds were determined. The skin whitening activity using in vitro or ex vivo tyrosinase and L-3,4-dihydroxyphenylalanine(L-DOPA) staining was examined. The total flavonoid content(TFC) was increased by 13.4% after 72h-fermentation. The viabilities of the B16F10 cells treated with the fermented and non-fermented control extracts were 100.26% and 92.15% at 500μg/ml, respectively. In addition, the inhibition of tyrosinase activity was increased by the fermented samples from 29.33% to 41.74% following fermentation for up to 72h. The tyrosinase activity of the untreated control group was increased to 145.69% in B16F10 cells. The results showed that I. britannica fermented by L. plantarum dose-dependently inhibited tyrosinase activity, which was stimulated by α-melanocyte stimulating hormone. These results suggest that lactic fermented I. britannica extracts can be used as effective skin-whitening materials.