Production of higher alcohols during indonesian tapé ketan fermentation

A study was made of the higher alcohols (fusel oils) produced during the Indonesian tapé ketan fermentation using Amylomyces rouxii as the principal mold, alone or in combination with yeasts belonging to genera commonly found in the tapé ketan fermentation (Endomycopsis, Candida, and Hansenula). Total fusel oils increased with length of fermentation. Fusel oils detected in the product distillate included isobutanol and isoamyl and active amyl alcohols. No n-propanol was detected. Isobutanol and isoamyl alcohols were formed in the largest amounts. A. rouxii alone produced nearly the same quantity of fusel oils (total production, 275 mg/liter at 192 h) as it did in combination with Endomycopsis burtonii (total production, 292 mg/liter at 192 h).A. rouxii and Endomycopsis fibuliger produced fusel oils totaling 72 mg/liter at 32 h and 558 mg/liter at 192 h. A. rouxii in combination with Candida yeasts produced somewhat more fusel oils, ranging from 590 to 618 mg/liter at 192 h. A. rouxii in combination with Hansenula yeasts produced the least fusel oils, totaling 143 to 248 mg/liter at 192 h. During the first 36 h, production of fusel oils was higher at 30 and 35 degrees C than at 25 degrees C. At 48 h fusel oil production was slightly higher at 30 degrees C than at 35 degrees C. Beyond 48 h, production of fusel oils was higher at 25 degrees C. A. rouxii in combination with Hansenula anomala and Hansenula subpelliculosa produced considerable ethyl acetate, ranging from 145 to 199 mg/liter at 36 h and 354 to 369 mg/liter at 192 h.     

The cover of living and dead corals from airborne remote sensing

Trends in coral cover are widely used to indicate the health of coral reefs but are costly to obtain from field survey over large areas. In situ studies of reflected spectra at the coral surface show that living and recently dead colonies can be distinguished. Here, we investigate whether such spectral differences can be detected using an airborne remote sensing instrument. The Compact Airborne Spectrographic Imager (Itres Research Ltd, Canada) was flown in two configurations: 10 spectral bands with 1-m² pixels and 6 spectral bands with 0.25-m² pixels. First, we show that an instrument with 10 spectral bands possesses adequate spectral resolution to distinguish living Porites, living Pocillopora spp., partially dead Porites, recently dead Porites (total colony mortality within 6 months), old dead (>6 months) Porites, Halimeda spp., and coralline red algae when there is no water column to confuse spectra. All substrata were distinguished using fourth-order spectral derivatives around 538 nm and 562 nm. Then, at a shallow site (Tivaru) at Rangiroa Atoll, Tuamotu Archipelago (French Polynesia), we show that live and dead coral can be distinguished from the air to a depth of at least 4 m using first- and fourth-order spectral derivatives between 562–580 nm. However, partially dead and recently dead Porites colonies could not be distinguished from an airborne platform. Spectral differences among substrata are then exploited to predict the cover of reef substrata in ten 25-m² plots at nearby Motu Nuhi (max depth 8 m). The actual cover in these plots was determined in situ using quadrats with a 0.01-m² grid. Considerable disparity occurred between field and image-based measures of substrate cover within individual 25-m² quadrats. At this small scale, disparity, measured as the absolute difference in cover between field and remote-sensing methods, reached 25% in some substrata but was always less than 10% for living coral (99% of which consisted of Porites spp.). At the scale of the reef (all ten 25-m² quadrats), however, disparities in percent cover between imagery and field data were less than 10% for all substrata and extremely low for some classes (e.g. <3% for living Porites, recently dead Porites and Halimeda). The least accurately estimated substrata were sand and coralline red algae, which were overestimated by absolute values 7.9% and 6.6%, respectively. The precision of sampling was similar for field and remote-sensing methods: field methods required 19 plots to detect a 10% difference in coral cover among three reefs with a statistical power of 95%. Remote-sensing methods required 21 plots. However, it took 1 h to acquire imagery over 92,500 m² of reef, which represents 3,700 plots of 25 m² each, compared with 3 days to survey 10 such plots underwater. There were no significant differences in accuracy between 1-m² and 0.25-m² image resolutions, suggesting that the advantage of using smaller pixels is offset by reduced spectral information and an increase in noise (noise was observed to be 1.6–1.8 times greater in 0.25-m² pixels). We show that airborne remote sensing can be used to monitor coral and algal cover over large areas, providing that water is shallow and clear, and that brown fleshy macroalgae are scarce, that depth is known independently (e.g. from sonar survey).     

Islands: stability, diversity, conservation

Islands present both a diversity and a stability paradox. They are often highly species-poor but have considerable biological interest in terms of extraordinary endemic genera and taxonomically isolated groups. They appear to be stable, as in some cases these organisms have persisted for many millions of years, and having an oceanic climate, extreme climatic events may be comparatively rare. However, when subject to extrinsic (anthropogenic) disturbance they do not appear to be stable, but often suffer catastrophic ecological change. These apparent paradoxes are resolved when it is realized that all these features are consequences of the same island characteristics: biotic isolation and oceanicity. As a result of these two characteristics, far oceanic islands are quantitatively different from continental systems in the nature of their ecological processes, which appear to give rise to an extreme punctuated equilibrium model of evolutionary change. Endemics may be ancient relict endemics displaying prolonged stasis and persistence, or products of adaptive radiation representing rapid punctuational events. A process-based definition of a relict endemic (palaeoendemic) is one whose founding lineage (i.e. the original continental source taxon) has not left any descendents. A corollary of this definition is that the time of divergence between an endemic and its continental sister-group should predate the colonization of the island by the now endemic lineage. An example is Dicksonia arborescens which has been on St Helena for at least 9 Myrs and no longer occurs in the likely source area of Africa. These relict endemics, frequent on islands, are important as the last remnants of tranches of biodiversity that have vanished elsewhere. Island conservation strategies require an integrated understanding of both sides of the diversity and stability paradox so that both island processes and island organisms can be conserved.     

Comparison of molecular and morphological data on St Helena: Elaphoglossum

The endemic elaphoglossoid ferns, Elaphoglossum dimorphum, E. nervosum and Microstaphyla furcata of St Helena, form a closely related group within section Lepidoglossa when analysed phylogenetically using sequences from the chloroplast trnL intron (partial) and trnL-F intergenic spacer. Microstaphyla furcata, traditionally placed in its own genus, is clearly shown to belong to Elaphoglossum confirming the previous transfer of this species to Elaphoglossum as E. bifurcatum. There is hardly any trnL-F sequence divergence between the species, in fact sequences of E. nervosum and E. dimorphum are identical. These results are consistent with the possible origin of E. dimorphum as a hybrid between E. bifurcatum and E. nervosum or with the view that the three species are the result of a recent radiation. The potential conflict between phylogenetic and morphological distinctness in determining species conservation priorities is discussed.     

The mating system ofElatostema (Urticaceae) in relation to morphology: A comparative study

To investigate why some species are dioecious and others monoecious, a data set of 14 morphological characters in 106 species ofElatostema was regressed onto mating system using partial multiple regression (controlling for subgeneric classification to avoid spurious associations). Morphology and mating system are significantly related (p = 0.05), and dioecious species tend to have large stipules, woody habit, and large leaves. The correlation of dioecy with large stipules is reported for the first time, but this character, like woodiness, is an indicator of plant size, suggesting a functional relationship of large plants (of the under-canopy) with dioecy.     

Legume comparative genomics: progress in phylogenetics and phylogenomics

The legumes are the focus of numerous rapidly expanding genomic projects, all of which involve members of one part of the Leguminosae, the subfamily Papilionoideae. This subfamily is monophyletic, and recent studies concur on a series of clades within it that are well supported and have received informal names. These include the Cladrastis clade, the genistoids (including Lupinus), the mirbelioids, the dalbergioids (including Arachis), the millettioids (including Glycine and Phaseolus), and the hologalegina (galegoid) legumes, which comprise the robinioids (including Lotus) and the inverted repeat loss (IRL) clade (including Medicago and Pisum). The canavanine-accumulating legumes appear to fall into a single clade, consistent with the idea that the production of this toxic amino acid evolved only once. Recent advances in analytical techniques for dating phylogenies support an 'early explosion hypothesis', suggesting that much of the morphological diversity of the legume family evolved rapidly around 50-60 million years ago. Within the papilionoids, the divergence between Glycine and Medicago is estimated to have taken place around 54 million years ago. There is strong evidence for a palaeoduplication event that affected both Glycine (a millettioid) and Medicago (from the IRL clade). As more genomic data are forthcoming for Arachis, it will be possible to test whether this event extends to the dalbergioids.     

The distribution and evolutionary history of the PRP8 intein

Background  

We recently described a mini-intein in the PRP8 gene of a strain of the basidiomycete Cryptococcus neoformans, an important fungal pathogen of humans. This was the second described intein in the nuclear genome of any eukaryote; the first nuclear encoded intein was found in the VMA gene of several saccharomycete yeasts. The evolution of eukaryote inteins is not well understood. In this report we describe additional PRP8 inteins (bringing the total of these to over 20). We compare and contrast the phylogenetic distribution and evolutionary history of the PRP8 intein and the saccharomycete VMA intein, in order to derive a broader understanding of eukaryote intein evolution. It has been suggested that eukaryote inteins undergo horizontal transfer and the present analysis explores this proposal.