Yellow Filaments Research Articles

Geolashon (Teloschistes flavicans), a natural yellow dye from the Peruvian Andes: traditional uses, bioactive extraction, and potential applications

Recently, interest in studying pigments from lichens has been aroused due to their bioactive properties and health benefits. The Geolashon (Teloschistes flavicans) is a thousand-year-old lichen from the Peruvian Andes characterized by its yellow filaments, traditionally used by the Peruvian inhabitants as a natural pigment for making handicrafts and medicinal purposes. In this sense, this article aims to compile all the studies on Geolashon as a source of natural yellow pigments, starting from its importance and applications by the Andean population to research on obtaining, characterizing, and properties of its extracts. Although studies on this lichen are limited, it was observed that the obtained from lichen are rich in 3-[1’-(2”,3”-dihydroxy-phenyl)-propyl]-7-hydroxy- chroman-4-one, vicanicin, parietin, other compounds and has antidiabetic, antibacterial, antileukemic, antimicrobial, anticancer and termiticide activity that would be interesting for use in the pharmaceutical, cosmetic, food and agricultural industries, generating added value in the final product. Aspects such as processing, functional properties, and toxicology of the bioactive components of Geolashon must be studied for its correct use.

Primulina fangdingii (Gesneriaceae), a new species from Guangxi, China

Primulina fangdingii, a species of Gesneriaceae new to science from Guangxi, China, is corroborated by both morphological and molecular evidence. The new species is similar to P. longzhouensis in leaf shape and size, but is easily distinguished from the latter by its adaxially glabrous leaf blades, yellow corolla with reddish inner surface and yellow filaments. It is also similar to P. repanda in corolla color and corolla shape, but can be diagnosed by its fleshy small leaves with glabrous adaxial surface, glandular and eglandular pubescent pedicels, yellow filaments and annular disc. In addition, Primulina fangdingii is somewhat similar to nine other species of Primulina, including P. cordifolia, P. danxiaensis, P. xiuningensis, P. chingipengii, P. cordistigma, P. diffusa, P. jingxiensis, P. petrocosmeoides and P. sinovietnamica, in either floral or vegetative morphology. However, all these species differ from P. fangdingii by a series of morphological characters. Phylogenetic analyses with ITS and two chloroplast DNA regions (rpL32‐trnL, trnL‐F) revealed that P. fangdingii is sister to P. luochengensis and isolated from its morphological relatives. Primulina fangdingii is described and illustrated here, and a key to the new species and its morphological allies is provided.

Visual function of red staminal filaments in a bee-pollinated plant

ABSTRACT Background Floral colour is a primary signal in plant-pollinator interactions. Presumably because bees lack red receptors, bee-pollinated flowers are rarely red. Hypericum (Hypericaceae) is a genus, with yellow flowers and filaments, mainly pollinated by bees. However, one species, H. ascyron exhibits unique red filaments. Aims We tested whether the red filaments influence pollinator visitation frequency and colour perception. Methods We examined whether H. ascyron require pollinators for seed set and compared insect visitation rates of H. ascyron with those of a sympatric yellow-filamented congener. Colour perception by bees was also estimated. Results Pollinator visitation substantially enhanced seed set under natural conditions and flowers of H. ascyron had similar rates of visitation by bees as their yellow-filamented congener. Red filaments per se absorbed ultraviolet light and therefore should not be perceived as a chromatic colour by bees. The chromatic contrasts between filaments and petals as perceived by pollinators was similar between species, whereas achromatic contrasts were higher in H. ascyron. Conclusions Pure-red staminal filaments work as well in attracting potential pollinators as the yellow filaments of congeners. Based on our findings, we suggest that the evolution of red filament colour may have been driven by factors other than pollinator attraction.

Miconia waimiri-atroari (Miconieae, Melastomataceae): a new species from the Brazilian Amazon Forest

Miconia waimiri-atroari is presented here as a new species from the Brazilian Amazon Forest. This new species has discolorous leaf blades, inflorescences with scorpioid branches, and petals and antesepalous stamen connectives with glandular trichomes. It has been misidentified as Miconia argyrophylla, another species from the Amazon Forest that has this same set of characters. However, the new species has cylindrical young branches (vs. quadrangular in M. argyrophylla), stellate trichomes on leaf abaxial surface (vs. arachnoid), stamens with yellow filaments that turn red in old flowers (vs. stamens with white filaments that only turn pale in old flowers), and style with glandular trichomes (vs. glabrous). At the moment, the species is only known from a small area north of Manaus, state of Amazonas, Brazil. Morphological description, illustrations, general comments and comparison to other similar species are also provided.

Paris variabilis (Melanthiaceae), a new species from southwestern China

Paris variabilis, a new species from the Wumengshan Mountains, southwestern China, is described and illustrated. The new species is placed in Paris section Euthyra. The new taxon was determined to be most morphologically similar to P. vietnamensis but differs in its oblong leaf blades with an acute apex, stamens 2–4 × petal number, greenish yellow filaments and an enlarged, purplish red style base. The phylogenetic placement of this species was assessed based on nuclear ribosomal ITS DNA sequences data. The results of morphological and phylogenetic analyses support the status of the taxon as a new species.

A new species of Barringtonia (Lecythidaceae) from Thailand and taxonomic notes on B. schmidtii

A new species of Barringtonia (Lecythidaceae), B. thailandica, is described from eastern Thailand. This species resembles B. acutangula in habit, leaf and flower characters, but differs mainly by its ellipsoid-shaped fruit with eight ribs. Additionally, B. schmidtii is reinstated as an independent species and it can be distinguished from its closely related taxa B. acutangula by its swollen leaf base, tomentose rachis, hypanthium and sepals, yellow filaments as well as obovoid-shaped, 4-angled and puberulent fruit. B. bicolor and B. badia are conspecific with B. schmidtii.

Primulina porphyrea (Gesneriaceae), a new species from southern Hunan, China

A new species of Gesneriaceae, Primulina porphyrea, is described and illustrated from southern Hunan, China. The new species resembles P. polycephala and P. yangshuoensis in leaf blade shape and indumentum of the plants, but it can be easily distinguished by having long petiole and purple leaf abaxial surface, purple corolla lobes and yellow corolla tube with several reddish-purple stripes, dark yellow filaments, and 3 staminodes. It flowers from May to August.

<i>Massonia citrina</i> (Hyacinthaceae, Hyacinthoideae)—a new species from the Western Cape Province (South Africa)

In the course of a taxonomic revision of the genus Massonia Houtt., Massonia citrina M.Pinter, Deutsch, U.Müll.- Doblies & D.Müll.-Doblies, a new species of this genus from the Western Cape Province (South Africa), is here described. This species is similar to members of the M. depressa group, but it can be easily distinguished by its yellow filaments and style and the longer perigone-filament tube. A complete morphological description of the new species is presented.

A new species Tulipa heweri related to T. praestans (Liliaceae)

A new species Tulipa heweri is described (subgenus Tulipa, section Eichleres, series Multiflorae). The species is related to T. praestans and differs by having smaller and less densely ciliate leaves, yellow or ochre flowers, yellow filaments, anthers and stigma, and a green ovary. The two species are allopatric, T. heweri being endemic to northern Afghanistan. Crosses between T heweri and T. praestans yielded moderate seed set.

Paeonia (Paeoniaceae) in Xizang (Tibet)

Paeonia (Paeoniaceae) in Xizang (Tibet)

Hydrogen evolution by photobleached Anabaena cylindrica

We have studied the evolution of hydrogen by photobleached filaments of the heterocystous bluegreen alga Anabaena cylindrica. The photobleached cells became orange-yellow due to the heavy accumulation of carotenoids. We found that the yellow filaments produced much larger amounts of hydrogen than the normal, green ones, while the nitrogenase activity responsible for hydrogen evolution increased to a lesser extent. We suggest that a reversible hydrogenase activity induced in photobleached filaments is responsible for the excess amount of hydrogen. 3-(3',4'-dichlorophenyl)-1,1-dimethyl urea (DCMU) inhibits the hydrogen evolution of the yellow filaments which produce much more oxygen and fix less CO2 than the green filaments. Therefore we consider the water to be a possible electron source for this hydrogenase. The low efficiency of light energy conversion (0.3%) in nitrogenase-catalyzed H2 evolution (Laczkó, 1980 Z. Pflanzenphysiol. 100, 241-245) is increased to 1.5-2% by the appearance of the reversible hydrogenase activity.

The Actinomyces of Potato Scab Demonstrated by Fluorescence Microscopy

The potato scab Actinomyces, like other acid-fast organisms, can be selectively impregnated with carbol-auramin and when exposed to ultraviolet radiation fluoresces bright yellow. The marked contrast of the bright yellow filaments permits ready localization and study of the micropathology of the tissue with a simple fluorescence microscope. The staining technic is done at room temperature and no counterstain is used. The fluorescence technic confirms Lutman's conclusion that the filaments are intercellular and grow within the middle lamellae. After complete removal of the paraffin, the sections are stained 4 minutes in carbol-auramin, (distilled water 97 ml., liquified phenol 3 ml., certified auramin 0.1 g.), washed, destained in a 0.5% solution of NaCl in 70% alcohol with 0.5 ml, HCl (conc.) per 100 ml., washed, and mounted in glycerin.