Peyer's patch-mediated intestinal immune system modulating activity of pectic-type polysaccharide from peel of Citrus unshiu.

An intestinal immune system modulating polysaccharide (CUI-3IIb-3-2, 18kDa) was purified from Citrus unshiu peel. CUI-3IIb-3-2 mainly comprised GalA, GlcA, Ara, Gal and Rha, and it consisted of 4-linked GalA, terminal Araf, 4- or 5-linked/3,4- or 3,5-branched Ara, terminal Gal, and 2-linked/2,4-branched Rha. After CUI-3IIb-3-2 digestion by endo-α-d-(1→4)-polygalacturonase, its hydrolysate was fractionated into PG-1 and PG-2. Methylation analyses of PG-1 and PG-2 using base-catalysed ß-elimination suggested that CUI-3IIb-3-2 be assumed as pectic-type polysaccharide. Since the activities of PG-1 and PG-2 were potently decreased, the whole polysaccharide structure of CUI-3IIb-3-2 would be essential to maintain the activity. Meanwhile, when CUI-3IIb was orally administered in mice, bone marrow cell proliferation and GM-CSF/IL-6 production from Peyer's patch cell were significantly higher (1.76- and 2.03/2.51-fold, respectively) than a saline. Therefore, a pectic-type polysaccharide from citrus peel could stimulate Peyer's patches and produce hematopoietic growth factors resulted in bone marrow cell proliferation.

An evaluation of the allelopathic potential of selected perennial groundcovers: foliar volatiles of catmint (Nepeta x faassenii) inhibit seedling growth.

Six perennial groundcovers including Alchemilla mollis, Nepeta x faassenii, Phlox subulata, Sedum acre, Solidago cutleri, and Thymus praecox were investigated for the allelopathic potential of their respective foliar tissues via evaluation of volatile constituents produced by foliage. These groundcovers were selected for further laboratory evaluation because of superior performance as weed-suppressive groundcovers in previous field experiments. Foliar volatile components of N. x faassenii exhibited the strongest inhibitory effects on seedling growth of curly cress (Lepidium sativum), but S. cutleri also showed allelopathic potential by reducing shoot growth of curly cress seedlings with extracted volatiles. Although A. mollis and P. subulata exhibited strong weed-suppressive traits in past field experiments, weed suppression is apparently associated with either competition for resources or other allelopathic mechanisms rather than an allelopathic effect caused by volatiles. Volatiles of N. x faassenii were further evaluated with gas chromatography coupled to mass spectrometry (GC-MS). A total of 21 chemical constituents were identified in the volatile cocktail; 17 components were identified from a direct crude leaf sample extraction, including sabinene, beta-pinene, beta-myrcene, 2-(2-ethoxyethoxy)-ethanol, 1,8-cineole, ocimene, neryl Acetate, 4aalpha,7alpha,7aalpha-nepetalactone, alpha-copaene, trans-caryophyllene, alloaromadendrene, 4abeta,7alpha,7abeta-nepetalactone, germacrene D, beta-farnesene, chi-cadinene, germacrene B, and beta-sesquiphellandrene. Five additional constituents were identified in a methanolic extract of dried of N. x faassenii foliage, but not the volatile cocktail collected from N. x faassenii foliage. These included methyl benzoate, 2,4-decadienal, neryl acetate, isodihydronepetalactone, and caryophyllene oxide. Three components, 2-(2-ethoxyethoxy)-ethanol, alloaromadendrene, and chi-cadinene, were not only detected in both the volatile mixture and the methanolic extract, but also in an aqueous foliar extract that exhibited potential allelopathic activity.

Sweet and sour cherry phenolics and their protective effects on neuronal cells.

The identification of phenolics from various cultivars of fresh sweet and sour cherries and their protective effects on neuronal cells were comparatively evaluated in this study. Phenolics in cherries of four sweet and four sour cultivars were extracted and analyzed for total phenolics, total anthocyanins, and their antineurodegenerative activities. Total phenolics in sweet and sour cherries per 100 g ranged from 92.1 to 146.8 and from 146.1 to 312.4 mg gallic acid equivalents, respectively. Total anthocyanins of sweet and sour cherries ranged from 30.2 to 76.6 and from 49.1 to 109.2 mg cyanidin 3-glucoside equivalents, respectively. High-performance liquid chromatography (HPLC) analysis revealed that anthocyanins such as cyanidin and peonidin derivatives were prevalent phenolics. Hydroxycinnamic acids consisted of neochlorogenic acid, chlorogenic acid, and p-coumaric acid derivatives. Glycosides of quercetin, kaempferol, and isorhamnetin were also found. Generally, sour cherries had higher concentrations of total phenolics than sweet cherries, due to a higher concentration of anthocyanins and hydroxycinnamic acids. A positive linear correlation (r2 = 0.985) was revealed between the total anthocyanins measured by summation of individual peaks from HPLC analysis and the total anthocyanins measured by the pH differential method, indicating that there was in a close agreement with two quantifying methods for measuring anthocyanin contents. Cherry phenolics protected neuronal cells (PC 12) from cell-damaging oxidative stress in a dose-dependent manner mainly due to anthocyanins. Overall results showed that cherries are rich in phenolics, especially in anthocyanins, with a strong antineurodegenerative activity and that they can serve as a good source of biofunctional phytochemicals in our diet.