Cladonia monomorpha,a neglected cup lichen from Europe

Abstract:Cladonia monomorpha is recognized as a distinct species in the Cladonia pyxidata group. It is characterized by thallus lobes with narrowly recurved margins, by the presence of discoid, bullate plates on the podetial surface and by long and sometimes branched proliferations of the scyphus margins supporting the apothecium discs. It is described from the Netherlands, where it occurs in acid inland sand dune areas with the highest terrestrial lichen diversity. It appears to be widespread in Europe on siliceous rock and acid sand.     

Cladonia petrophila,a new species from eastern North America

Cladonia petrophila, an overlooked, usually sterile species, morphologically similar toC. apodocarpa andC. caespiticia, is described as new on the basis of its distinctive chemistry, perlatolic and fumarprotocetraric acids, and habitat preference for moist non-calcareous rock.     

Cladonia krogiana,a new xanthone-containing species from Norway

Abstract:The new lichen species Cladonia krogiana is described from eight localities in SE Norway. It resembles C. polycarpoides morphologically, but differs in containing barbatic acid and chlorovinetorin.     

Cladonia singhii and other new reports of Cladonia from the Eastern Himalayan Region of India

Abstract:A new species, Cladonia singhii Ahti & Dixit (type from the state of Arunachal Pradesh), is described. A further seven Cladonia species, C. corniculata, C. kanewskii, C. laii, C. luteoalba, C. mauritiana, C. mongolica and C. rei, are reported as new to the recent checklist of lichens of the Indian subcontinent. The presence of C. cartilaginea in India is confirmed.     

Water-soluble phenolic compounds in lichens

The quantity and the qualitative composition (for some species) of phenolic compounds (PC) washed out of the intact thalli of lichens of the orders Peltigerales (the genera Peltigera, Solorina, and Nephroma) and Lecanorales (the genera Cladonia, Alectoria, and Cetraria) were studied. It was shown that the quantity of leachable PCs in Peltigerales was on average 2–3 times higher than in Lecanorales. At the same time, the extractability of PC from intact thalli by water was higher in Lecanorales than in Peltigerales: 48–88% and 34–70%, respectively, of the PC content in ethanol extracts from crushed thalli (i.e., of the total content of soluble PC). Water-soluble PC in the lichens Peltigera aphthosa, Solorina crocea, Cetraria islandica, Flavocetraria nivalis, Cladonia uncialis, and Cladonia arbuscula were represented by 7–12 phenolic compounds with similar qualitative composition in the species of the same order. The most part of water soluble PC were phenylpropanoids. All of the studied species showed the presence of p-hydroxybenzoic acid derivatives; vanillic and protocatechuic acid derivatives were found in Cetraria and Cladonia species, respectively.     

Aliphatic compounds in some lichens

The presence of free fatty acids in Cetraria nivalis and Cladonia gonecha has been demonstrated. Saturated wax esters occur in Cetraria cucullata and C. nivalis, whilst free alkanols were found in C. cucullata. Triglycerides in C. nivalis were detected by their MS fragmentation patterns. Hexa(α-hydroxyisovalerate) is present in C. nivalis and Cl. gonecha, and the presence of ribitol in C. nivalis was demonstrated by identification of its acetonide in an acetone extract.     

STRUCTURAL STUDIES ON THE GALACTOMANNANS OF LICHENS OF THE GENUSCLADONIA

Galactomannans were isolated fromCladonia signata,C. furcata,C. imperialis, andC. clathratavia successive alkaline extraction and precipitation with Fehling solution and Cetavlon. They were investigated using¹³C-NMR spectroscopy, methylation analysis, and Smith degradation, and their specific rotations and monosaccharide compositions determined. As with galactomannans of otherCladoniaspecies, they contained (1→6)-linked main chains of α-mannopyranose, which were non-substituted (structure4in Fig. 2), mono-substituted at O-2 with α-mannopyranose (structure6) or α-galactopyranose (structure1), O-4 with β-galactopyranose (structure2), and disubstituted at O-2 and O-4 with α-mannopyranosyl and β-galactopyranosyl units, respectively (structure5). Disubstitution was present to a greater extent in the galactomannans ofC. clathrataandC. imperialisthan in those ofC. signataandC. furcata. In the case of the galactomannans ofC. furcata,C. clathrata, andC. imperialis, substitution also occurred at O-2 withO-β-galactofuranosyl-(1→6)-O-α-mannopyranosyl units (structure7). As observed in previous investigations, the C-1 portion of the¹³C-NMR of mannose-containing polysaccharides is typical of the lichen species. However, those of galactomannans ofC. imperialisandC. clathrataare almost identical and, although other chemical data showed many structures in common, some differences were evident.     

The degradation of l-threose at Maillard reaction conditions

l-Threose, a comparatively unstable aldose, is produced from l-ascorbic acid in the presence of oxygen and participates vigorously in Maillard reactions, even at comparatively mild conditions. In the present study, the degradation of l-threose at pH 7.0 alone, in the presence of N-α-acetyl-l-lysine, and at pH 2.0 alone at 37°C was investigated by identification of some of the products produced in the reactions by means of GLC and GLC-MS. Among the compounds identified were3-deoxy-tetros-2-ulose (1), the predicted alkaline rearrangement product derived from 1 (2,4-dihydroxybutyrate, the 4-carbon metasaccharinic acid), as well as glyceraldehyde. Isotopic tracer studies clearly show that the glyceraldehyde is produced by loss of C-1 from the starting l-threose molecule. The presence of N-acetyl lysine in incubation solutions appears to accelerate the production of 1, but the formation of glyceraldehyde appears to be independent of the lysine derivative.     

Conservation genetics of the highly endangered Azorean endemics <Emphasis Type="Italic">Euphrasia azorica</Emphasis> and <Emphasis Type="Italic">Euphrasia grandiflora</Emphasis> using new SSR data

In the Azores Islands, two Euphrasia L. (Orobanchaceae) endemic species are recognized: Euphrasia azorica H.C.Watson, an annual herb, in Flores and Corvo, and Euphrasia grandiflora Hochst. ex Seub., a semi-shrub, in Pico, São Jorge and Terceira. Both species are highly endangered and protected by the Bern Convention and Habitats Directive. A population genetics study was conducted with new microsatellite primer pairs in 159 individuals of E. azorica and E. grandifolia, sampled from populations in Flores, Corvo, Pico and São Jorge. Allele sizing suggested that E. azorica is a diploid while E. grandiflora is a tetraploid. Euphrasia grandiflora revealed higher genetic diversity then E. azorica. The E. grandiflora population of Morro Pelado in São Jorge, displayed higher genetic diversity when compared with all others, while the E. azorica population of Madeira Seca in Corvo, showed the lowest. Private and less common bands were also overall higher in E. grandiflora populations. Population genetic structure analysis confirmed a distinctiveness between the two Azorean endemic Euphrasia, in addition to island-specific genetic patterns in E. azorica. The genetic structure obtained for E. grandiflora was complex with the populations of Cabeço do Mistério in Pico Island and of Pico da Esperança in São Jorge sharing the same genetic group, while a putative spatial barrier to gene flow was still retrieved between both islands. Although some populations of both species might benefit from propagation actions, studies are needed on plant host species and translocations between islands or between some populations of a same island should be avoided, due to the occurrence of putative ESUs. Eradication of invasive species and control of grazing will be fundamental to promote in situ restauration.     

矮石蕊在东亚的地位

中国和日本有关具粉末状粉芽的矮石蕊(Cladonia humilis)的报导大多数实际上是指本文中描述的新种,黑氏石蕊(Cladonia kurokawae Ahti & S. Stcnroos).其特征是杯体深裂,含有黑茶渍素和富马原岛衣酸.真正的矮石蕊在中国和日本是很少见的;日本的种类中,含有黑茶渍素和波衣酸的两个化学型都存在.     

Nutritive value of terricolous lichens for reindeer in winter

Abstract:In contrast to virtually all other species of ruminants, reindeer (Rangifer tarandus) eat substantial amounts of lichens in winter. Several different species of lichens are eaten and most are highly palatable. The chemical composition and the in vitro digestibility of six species of terricolous lichens commonly eaten by reindeer were measured. Ruminal inoculum was obtained in winter from six free-ranging reindeer that had been grazing on natural pastures in northern Norway. Analysis of the plant parts recovered from their rumens confirmed that the animals had been eating a mixed diet that included both lichens and vascular plants. The chemical composition and the in vitro digestibility of the different species of lichens varied considerably between species and genera. Cetraria islandica, C. nivalis andCladonia arbuscula were highly digestible [69–77% dry matter (DM)], Stereocaulon paschale was poorly digestible (43% DM), whereas Cladonia stellaris and C. gracilis had an intermediate digestibility (56–57% DM). Mixing Cladonia stellaris with vascular plants (50:50) had no effect on the in vitro digestibility of the combined substrates. The in vitro digestibility of Cladonia stellaris in inoculum from two captive reindeer which had had no access to lichens was very low (10% DM). This shows that the source of inoculum used for digestibility trials has a major effect on the apparent digestibility of the substrates. Evidently, the extent to which reindeer are able to utilize lichens depends on the species that are selected and on what the animals have been eating recently.     

Gap dynamics and regeneration strategies in <Emphasis Type="Italic">Juniperus-Laurus</Emphasis> forests of the Azores Islands

We asked the following questions regarding gap dynamics and regeneration strategies in Juniperus-Laurus forests: How important are gaps for the maintenance of tree diversity? What are the regeneration strategies of the tree species? Thirty canopy openings were randomly selected in the forest and in each the expanded gap area was delimited. Inside expanded gaps the distinction was made between gap and transition zone. In the 30 expanded gaps a plot, enclosing the gap and transition zone, was placed. In order to evaluate the differences in regeneration and size structure of tree species between forest and expanded gaps, 30 control plots were also delimited in the forest, near each expanded gap. In the 60 plots the number of seedlings, saplings, basal sprouts and adults of tree species were registered. Canopy height and width of adult individuals were also measured. The areas of the 30 gaps and expanded gaps were measured and the gap-maker identified. Juniperus-Laurus forests have a gap dynamic associated with small scale disturbances that cause the death, on average, of two trees, mainly of Juniperus brevifolia. Gap and expanded gap average dimensions are 8 and 25 m², respectively. Gaps are of major importance for the maintenance of tree diversity since they are fundamental for the regeneration of all species, with the exception of Ilex azorica. Three types of regeneration behaviour and five regeneration strategies were identified: (1) Juniperus brevifolia and Erica azorica are pioneer species that regenerate in gaps from seedlings recruited after gap formation. However, Juniperus brevifolia is a pioneer persistent species capable of maintaining it self in the forest due to a high longevity and biomass; (2) Laurus azorica and Frangula azorica are primary species that regenerate in gaps from seedlings or saplings recruited before gap formation but Laurus azorica is able to maintain it self in the forest through asexual regeneration thus being considered a primary persistent species; (3) Ilex azorica is a mature species that regenerates in the forest.     

Hantupeptins B and C,cytotoxic cyclodepsipeptides from the marine cyanobacterium Lyngbya majuscula

Hantupeptins B (2) and C (3) were isolated, along with the previously reported hantupeptin A (1), from the marine cyanobacterium, Lyngbya majuscula, collected from Pulau Hantu Besar, Singapore. Their structures were elucidated by interpretation of extensive 1D and 2D NMR spectroscopic data. Compounds 2 and 3 are cyclic depsipeptides consisting of five α-amino/hydroxy acid residues, including phenyllactic acid, proline, N-methyl-valine, valine, N-methyl-isoleucine, and a β-hydroxy acid unit with different degrees of unsaturation at the terminal end of each molecule. The absolute configurations of the common amino acids and phenyllactic acid were determined by the advanced Marfey’s and chiral HPLC analyses, respectively. The complete stereochemistry of 3-hydroxy-2-methyl-7-octynoic acid moiety in hantupeptin A was elucidated by a combination of homonuclear J-resolved 2D NMR experiments and by Mosher’s method. Hantupeptins B and C showed moderate in vitro cytotoxicity when tested against MOLT-4 (leukemic) and MCF-7 (breast cancer) cell lines.     

Determination of absolute configuration of salvic acid,an ent-labdane from Eupatorium salvia,by vibrational circular dichroism

The relative stereochemistry at C13 and the absolute configuration of salvic acid, a constituent of the leaves of Eupatorium salvia, were established as the 13-(R)-ent-labdane 1. The results follow from vibrational circular dichroism measurements of the derived O-methyl ether methyl ester 3 which were compared to DFT B3LYP/DGDZVP calculated spectra. The relative stereochemistry of salvic acid at C13 was independently verified by single crystal X-ray diffraction measurements of 1, and of its derived diol 4.     

Chevalierinoside B and C: Two new isoflavonoid glycosides from the stem bark of Antidesma laciniatum Muell. Arg (syn. Antidesma chevalieri Beille)

Chevalierinosides B (1) and C (2), two new isoflavonoid glycosides, characterized as biochanin A 7-O-[β-d-apiofuranosyl-(1→2)-β-d-glucopyranoside] and genistein 7-O-[β-d-apiofuranosyl-(1→2)-β-d-glucopyranoside], together with the known isoflavonoids, chevalierinoside A (3) and genistein 7-O-β-d-glucopyranoside (4), kaempferol 3-O-β-d-glucopyranoside (5) and triterpenes, friedelin (6), betulinic acid (7), 30-oxobetulinic acid (8), 30-hydroxybetulinic acid (9), were isolated from the stem bark of Antidesma laciniatum Muell. Arg. (syn. Antidesma chevalieri Beille). Their structures were established by direct interpretation of their spectral data, mainly HR-TOFESIMS, 1D-NMR (¹H, ¹³C and DEPT) and 2D-NMR (COSY, NOESY, TOCSY, HSQC and HMBC), and by comparison with the literature.     

Structural and synthetic studies on the retrofractamides—amide constituents of Piper retrofractum

Two new unsaturated amides, retrofractamides A and C, were isolated from the total above-ground parts of Piper retrofractum. Retrofractamide A was shown to be N-isobutyl-9(3′,4′-methylenedioxyphenyl)2E,4E,8E-nonatrienamide from spectroscopic and chemical investigations. The structure 6 for retrofractamide C was suggested from spectroscopic and chemical studies and was confirmed by a total stereoselective synthesis. The presence of sesamin and 3,4,5-trimethoxydihydrocinnamic acid as well as two higher homologues of retrofractamide A, viz. pipericide (retrofractamide B) and retrofractamide D was demonstrated. The synthesis of pipericide was also achieved.     

Macrolide (cucujolide) biosynthesis in the rusty grain beetle,Cryptolestes ferrugineusI

Males of the cucujid grain beetles, Cryptolestes ferrugineus (Stephens), C. pusillus (Schönhen), C. turcicus (Grouvelle), Oryzaephilus mercator (Fauval) and O. surinamensis (L.), produce seven structurally related macrolides (“cucujolides”). Species-specific combinations of these macrocyclic lactones function as aggregation pheromones. To study the biosynthesis of these cucujolides, mixed sex cultures of the rusty grain beetle, C. ferrugineus, were fed oats impregnated with radiolabelled substrates. Culture volatiles were trapped on Porapak Q, eluted by back-flushing with solvent, concentrated and purified to constant specific activity by high performance liquid chromatography and preparative gas chromatography. The incorporation of radiolabelled acetate and mevalonate into cucujolide I [4(E),8(E)4,8-dimethyldecadien-10-olide] provided evidence that this pheromone is of terpenoid origin. The efficient incorporation of radiolabelled fatty acid substrates into cucujolides II 3(Z)dodecen-11-olide], III 5(Z)tetradecen-13-olide], IV [3(Z),6(Z)dodecadien-11-olide] and V [5(Z),8(Z)tetradecadien-13-olide] provided evidence that these cucujolides are of fatty acid origin. Radiolabelled palmitic acid was incorporated into cucujolides II, III, IV and V; radiolabelled oleic acid was incorporated into II and III; and radiolabelled linoleic acid was incorporated into IV. Radiolabelled acetate was incorporated into cucujolides II, III and V, indicating that C. ferrugineus can produce these cucujolides de novo.     

Flavanone derivatives from Macaranga tanarius

A new flavanone, epoxynymphaeol C (1), was isolated from the acetone extract of the leaves of Macaranga tanarius, together with two known compounds, nymphaeols B (2) and C (3). The structure of the new compound was determined by NMR and mass spectral data. Chemotaxonomic significance for the presence of the flavanone derivatives in M. tanarius is discussed.     

Batatins III-VI, glycolipid ester-type dimers from Ipomoea batatas

Batatins III-VI (1-4), glycolipid ester-type dimers, were isolated from the tuberous roots of sweet potato (Ipomoea batatas) using recycle high performance liquid chromatography. Their structures were characterized by means of several high-resolution NMR and mass spectrometry techniques. These compounds are the first examples of ester-type dimers which consist of two units of the heterotetrasaccharide operculinic acid C. Each unit was esterified by a different amount and type of acid residues: (2S)-methylbutanoic, cinnamic, decanoic (capric) and dodecanoic (lauric) acids. Batatins III-VI (1-4) are an example of the presence of a large number of resin glycoside congeners in each morning glory species caused by partial acylation of their constitutive saccharide cores.     

Glycosides for testing glycosidases: Vinyl,l-ethoxyethyl,and l-ethoxybut-3-enyl d-glucopyranosides

The reaction of ethyl vinyl ether and 2,3,4,6-tetra-O-acetyl-β-d-glucopyranose (1) in the presence of Hg-(OAc)₂ and toluene-p-sulphonic acid as catalysts yielded the acetylated vinyl, l-ethoxyethyl, and l-ethoxybut-3-enyl glycosides in varying proportions. Crystalline l-ethoxybut-3-enyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyranoside (2), vinyl 2,3,4,6-tetra-O-acetyl-α-d-glucopyranoside (3), and l-ethoxyethyl 2,3,4,6-tetra-O-acetyl-β-d-glucopyranoside (4) were isolated by chromatography. Compound 4 was also prepared by the reaction of 1 with cold acetaldehyde diethyl acetal containing a trace of acetic acid, and its α anomer (5) by the reaction of 1 with boiling acetaldehyde diethyl acetal containing a trace of acetic acid. Each deacetylated d-glucoside was cleaved by the corresponding d-glucosidase, to yield d-glucose and either acetaldehyde (from deacetylated 3-5) or but-3-enal (from deacetylated 2).