Impact of Lymphopenia on Definitive Treatment of Locally Advanced Cervical Cancer

PURPOSE/OBJECTIVE(S)

Pre-treatment lymphopenia prior to initiating treatment has been correlated with reduced survival in a number of different cancers. The purpose of this study is to evaluate the association between lymphopenia and survival in women with locally advanced cervical cancer (LACC) treated with primary chemoradiation (CRT).

MATERIALS/METHODS

We retrospectively reviewed patients with LACC treated at a single institution from 2005 - 2021 with available lymphocyte information. Patient and treatment characteristics were recorded including age, tumor size and stage, EBRT dose/fractionation, and brachytherapy dosimetry data. Absolute lymphocyte counts (ALC) were collected prior to initiating CRT and at 3-month intervals following CRT and graded based on severity of lymphopenia using CTCAE v 5.0. Overall survival (OS), progression free survival (PFS), and local control (LC) were calculated from the start of treatment to date of last follow-up. Kaplan-Meier survival analysis was performed to evaluate whether lymphocyte changes were associated with OS, PFS, or LC.

RESULTS

A total of 124 patients met study inclusion criteria with stage IB - IV disease (41 stage I, 41 stage II, 36 stage III, 6 stage IV) and a median follow up of 3.6 years (range 0.2-16.5 years). The median age was 49 years (range 26-77). The median EBRT dose was 45 Gy (range: 26-57.5 Gy) and 44.2% of patients received para-aortic (PA) nodal EBRT (28.8% elective and 15.4% with positive PA nodes). 5-year OS, PFS, and LC were 60.3% (95% CI 51.5-70.7), 47.5% (95% CI 39-58), and 75.5% (95% CI 67.3-82.9), respectively. Pre-treatment lymphopenia (ALC <1000 cells/mm3) was present in 11 (9%) patients. When the total cohort was divided into patients with and without pre-treatment lymphopenia, OS was statistically improved in the patients without baseline lymphopenia, with a 5-year OS of 63.2% (95% CI 53.9-73.9) versus 35.3% (95% CI 14.5-86.3) in the lymphopenia group (p = 0.034). LC also trended to being improved in the patients without lymphopenia, though this did not reach statistical significance in our small sample size of lymphopenic patients, with 5-year LC of 76.8% (95% CI 68.4-84.3) versus 67.5% (05% CI 36.6-93.8), p = 0.45.

CONCLUSION

In this single institution experience of LACC treated with definitive CRT, we found that baseline lymphopenia is associated with inferior OS. Patients with higher pre-CRT ALC may represent a population with more robust immune systems, producing more favorable tumor responses to treatment. Additional studies are warranted to investigate the evolving role of combined EBRT and systemic therapy in LACC.

The influence of the Southern Oscillation Index on the timing of breeding of a forest-bird community in south-eastern Australia

ContextLong-term changes in the breeding phenology of bird communities have been widely studied. For many species, breeding appears to be starting earlier as temperatures increase. For south-eastern Australia, such a trend has not so far been demonstrated. AimsThe aim was to determine how the date of laying of the first egg (FE; for sedentary species) or arrival times (for migratory species) responded to climatic factors such as rainfall, air temperature and the Southern Oscillation Index (SOI), and whether FE or arrival time showed a trend through time. MethodsThe date of laying of the first egg (FE) for 13 sedentary species of birds was recorded over 18 (1975–1984 and 2007–2014) breeding seasons (August to January) at a single site in a coastal forest in south-eastern Australia. The arrival times for seven migratory species were also recorded for these seasons. Key resultsLinear mixed models showed that FE was negatively correlated with the mean monthly SOI for April to July (A-J SOI), the period directly before the breeding season. Eggs were laid earlier when A-J SOI was positive and later when it was negative. SOIs calculated over different combinations of months showed that those for the January to March period had no influence on FE. FE was not related to minimum or maximum temperatures during April to July, despite increases in temperature between 1975 and 2014, nor was it related to rainfall between April and July. Mixed linear models showed that arrival date for migratory species became earlier between 1975 and 2014, but was uninfluenced by A-J SOI or rainfall. ConclusionsMigratory species arrived earlier by 0.27 days per year. However, this was at least an order of magnitude smaller than annual temporal changes in FE for sedentary species (6–7 days) associated with cyclical SOI fluctuations. Changes in SOI dominated the annual breeding phenology of the community. ImplicationsThe mechanisms by which A-J SOI influences the timing of nesting may be related to the primary productivity of forests and the influence of this on insect abundance. There are few data on these factors.

Microbial biosurfactants: current trends and applications in agricultural and biomedical industries

Synthetic surfactants are becoming increasingly unpopular in many applications due to previously disregarded effects on biological systems and this has led to a new focus on replacing such products with biosurfactants that are biodegradable and produced from renewal resources. Microbially derived biosurfactants have been investigated in numerous studies in areas including: increasing feed digestibility in an agricultural context, improving seed protection and fertility, plant pathogen control, antimicrobial activity, antibiofilm activity, wound healing and dermatological care, improved oral cavity care, drug delivery systems and anticancer treatments. The development of the potential of biosurfactants has been hindered somewhat by the myriad of approaches taken in their investigations, the focus on pathogens as source species and the costs associated with large-scale production. Here, we focus on various microbial sources of biosurfactants and the current trends in terms of agricultural and biomedical applications.

No Evidence Against Sketch Reinstatement of Context, Verbal Labels or the Use of Registered Intermediaries for Children with Autism Spectrum Disorder: Response to Henry et al. (2017)

Recently, Henry et al. (J Autism Dev Disord 8:2348-2362, 2017) found no evidence for the use of Verbal Labels, Sketch Reinstatement of Context and Registered Intermediaries by forensic practitioners when interviewing children with a diagnosis of autism spectrum disorder. We consider their claims, noting the limited ecological validity of the experimental paradigm, the impacts of repeated interviewing where retrieval support is not provided at first retrieval, question the interviewer/intermediary training and their population relevant experience, and comment on the suppression of population variances. We submit that rejecting these techniques on the basis of this study is completely unwarranted and potentially damaging, particularly if used in legal proceedings to undermine the value of testimony from children with ASD, who continually struggle to gain access to justice.

Rhamnolipids and lactonic sophorolipids: natural antimicrobial surfactants for oral hygiene

AIMS

To assess the efficacy of rhamnolipid (mixture of monorhamnolipid and dirhamnolipid congeners), purified monorhamnolipid, dirhamnolipid and lactonic sophorolipid biosurfactants against pathogens important for oral hygiene.

METHODS AND RESULTS

Acquired and produced biosurfactants were fully characterized to allow the antimicrobial activity to be assigned to the biosurfactant congeners. Antimicrobial activity was assessed using the resazurin-aided microdilution method. Mixed rhamnolipid JBR425 (MR) and lactonic sophorolipids (LSLs) demonstrated the lowest minimum inhibitory concentration (MIC) which ranged between 100 and 400 μg ml^-1 against Streptococcus mutans, Streptococcus oralis, Actinomyces naeslundii, Neisseria mucosa and Streptococcus sanguinis. Combining these biosurfactants with standard antimicrobial agents namely chlorhexidine, sodium lauryl sulphate, tetracycline HCl and ciprofloxacin showed a dramatic drop in the MIC values. In addition, in vitro studies demonstrated the biosurfactants' ability to prevent and disrupt oral pathogens biofilms. The increased permeability of microorganisms treated with biosurfactant, as shown using bisbenzimide dye, in part explains the inhibition effect.

CONCLUSION

The results demonstrate that rhamnolipids and LSLs have the ability to inhibit oral pathogens both in planktonic and oral biofilm states.

SIGNIFICANCE AND IMPACT OF THE STUDY

The findings indicate the potential value of biosurfactants for both oral hygiene and the pharmaceutical industries since there is a serious need to reduce the reliance on synthetic antimicrobials and antibiotics.

Pseudomonas aeruginosa biofilm disruption using microbial surfactants

AIMS

To establish the ability of the rhamnolipids biosurfactants from Pseudomonas aeruginosa, in the presence and absence of caprylic acid and ascorbic acid, to disrupt bacterial biofilms, compared with the anionic alkyl sulphate surfactant Sodium dodecyl sulphate (SDS).

METHODS AND RESULTS

Pseudomonas aeruginosa ATCC 15442 biofilms were disrupted by rhamnolipids at concentrations between 0·5 and 0·4 g l(-1) and with SDS at 0·8 g l(-1) . The combination of rhamnolipids 0·4 g l(-1) and caprylic acid at 0·1 g l(-1) showed a remarkable effect on biofilm disruption and cell killing. After 30 min of treatment most of the biofilm was disrupted and cell viability was significantly reduced. Neither caprylic acid nor ascorbic acid has any effect on biofilm disruption at 0·1 g l(-1) . SDS is an effective antimicrobial agent; however, in the presence of caprylic acid its effect was neutralized.

CONCLUSIONS

The results show that rhamnolipids at low concentration in the presence of caprylic acid are promising molecules for inhibition/disruption of biofilms formed by Ps. aeruginosa ATCC 15442.

SIGNIFICANCE AND IMPACT OF THE STUDY

The disruption of biofilms has major significance in many industrial and domestic cleaning applications and in medical situations.

Effects of three whole-farmlet management systems on Merino ewe fat scores and reproduction

As part of the Cicerone Project’s whole-farmlet experiment on the Northern Tablelands of New South Wales, Australia, the fat scores and reproductive performance of ewes were measured to assess the effect of different management systems on these important production parameters over time. The three farmlets (each of 53 ha) included one (farmlet B) subjected to ‘typical’ district management consisting of moderate levels of inputs and a target stocking rate of 7.5 dse/ha, with flexible grazing management across eight paddocks. A second farmlet (A) was managed in a similar fashion to farmlet B with respect to number of paddocks and grazing management, but modified by high rates of pasture renovation and higher levels of soil fertility, with a target stocking rate of 15 dse/ha. The third farmlet (C) was managed at the same level of moderate inputs as farmlet B but employed intensive rotational grazing over 37 paddocks and also had a high target stocking rate of 15 dse/ha. The experiment was conducted over 6.5 years from July 2000 to December 2006. In spite of the fact that target levels of stocking rate were chosen at the beginning of the experiment, stocking rate, together with fat scores and reproduction were treated as emergent properties of each farmlet system. Joining took place in April–May and lambing occurred in September–October of each year. Over the first 2 years of the experiment, there were few differences among farmlets in ewe fat scores or reproductive performance. From 2003 onwards, while the percentage of ewes pregnant was similar between farmlets, the average proportion of multiple births (ewes scanned in late July, with twins) was 30%, 16% and 12%, respectively, on farmlets A–C. However, lamb losses were greater on farmlet A, with average lamb mortalities recorded on farmlets A–C of 29%, 10% and 19%, respectively. Over the duration of the experiment, ewes on farmlets A and B were more often above a fat score level of 3, and less often below 2.5, than were ewes from farmlet C. Differences among farmlet ewes in fat score were found to be significant in 7 of the total of 13 assessments over the duration of the experiment. A generalised additive model applied to whole-farmlet data showed that green digestible herbage, legume herbage, stocking rate, the amount of supplement fed and especially the proportion of each farmlet grazed at any one time all influenced fat scores of ewes. While fat scores and conception rates tended to be highest on farmlet A, farmlet B had slightly better reproductive outcomes due to less lambing losses, whereas ewes on farmlet C tended to have somewhat lower fat scores and levels of reproduction. These farmlet-scale findings highlighted the importance for livestock managers to focus not only on grazing management, stocking rate and stock density during lambing, but also on the availability of sufficient green, and especially legume herbage, and the difficulty of overcoming a deficit in quality herbage with supplementation.

Selection of experimental treatments, methods used and evolution of management guidelines for comparing and measuring three grazed farmlet systems

The Cicerone Project was a collaborative effort by livestock producers, researchers and extension specialists, which aimed to explore the profitability and sustainability of grazing enterprises on the Northern Tablelands of New South Wales, Australia. A major part of the Project was the creation of a moderate scale, unreplicated farmlet experiment. The process of selecting the farmlet treatments and the design of the experiment involved considerable negotiation over an extended period in order to achieve ‘ownership’ by all those involved. The farmlets were designed to compare a typical farmlet (B) as the control with a second farmlet (A), which received higher levels of pasture renovation and soil fertility, and a third (C), which employed intensive rotational grazing management with short graze and long rest periods. Management guidelines were developed for all soil, pasture, livestock and grazing management decisions on the three farmlets. Whole-farmlet data are presented for the pastures sown, fertiliser applied, supplement fed, the stocking rates attained and the pattern of graze and rest periods over the experimental period from July 2000 to December 2006. Over the first 4 years of the trial, pastures were renovated on 71% of farmlet A while 8% of each of farmlets B and C were renovated. The rates of fertiliser applied to the three farmlets varied according to soil test values and the different target values for soil phosphorus and sulfur. In the first year of the trial (2000–01), the annual average stocking rates on farmlets A, B and C were 9.5, 7.9 and 9.1 dry sheep eqivalents/ha, respectively, whereas by the fifth year (2005), the stocking rates were 11.2, 7.8 and 7.4 dry sheep equivalents/ha, respectively. This paper provides details of the general methods used in the farmlet trial, of relevance to a series of related papers which explore all aspects of the farmlet experiment and its findings. It also reports on the selection and definition of the farmlet treatments and describes how the guidelines evolved over the duration of the trial in response to the practical realities of conducting this complex, agroecosystem experiment.

Livestock weights in response to three whole-farmlet management systems

This paper reports changes in livestock weights recorded in a whole-farmlet experiment, which aimed to examine the profitability and sustainability of three different pasture and grazing management strategies. The assessment of liveweights was considered a key component of measuring the integrated effects of the farmlet-scale treatments. The three farmlets comprised a typical management regime, which employed flexible rotational grazing over eight paddocks with moderate soil fertility (farmlet B), a system based on the same grazing management and paddock number but with higher levels of sown pasture and soil fertility (farmlet A) and a farmlet with moderate soil fertility and intensive rotational grazing over 37 paddocks (farmlet C). Early in the experimental period, there were no significant differences between farmlets in the liveweight of any class of livestock. However, from the second year onwards, as the pasture renovation, soil fertility and grazing management treatments took effect, differences in liveweight between farmlets became more apparent and significant. The stocking rate, which was treated as an emergent property of each farmlet, reached a maximum annual average value after 5 years of 12.6, 8.5 and 7.7 dry sheep equivalents (dse)/ha on farmlets A, B and C representing 84, 113 and 51% of their respective target stocking rates which were 15, 7.5 and 15 dse/ha. The liveweights of ewes, both before joining and during pregnancy, varied with year and farmlet with those on farmlets A and B tending to be significantly heavier than those on farmlet C. From 2003 to 2006, liveweights were significantly (P < 0.001) affected by a wide array of factors and their interactions including: date, ewe age, green digestible herbage, legume herbage mass, proportion of farmlet grazed, stocking rate and level of supplementary feeding. The weights of lambs/weaners/hoggets, both pre- and post-weaning, were at times also higher on farmlets A and B compared with those on farmlet C and were affected by a similar range of factors to those which affected ewe weights. Similar relative differences also applied to the liveweights of the other livestock run on the farmlets, namely wethers and non-reproductive cattle. The results suggest that stocking rate was able to be increased towards the higher target of farmlet A due to the higher level of pasture renovation and soil fertility on that farmlet, which led to high liveweights per head as well as the higher stocking rate. However, as the stocking rate increased on farmlet A, the differences between farmlets in liveweight per head diminished and the need for supplementary feeding increased. In contrast, the intensive rotational grazing practised on farmlet C did not allow the farmlet to increase its stocking rate towards its higher target. It appears that the higher proportion of each of farmlets A and B grazed at any one time allowed all classes of livestock to reach higher liveweights per head than on farmlet C, due presumably to the greater proportion of those two farmlets grazed at any one time.

Reflections on the concept, conduct and findings of the producer-led Cicerone Project

The Cicerone Project began as a producer-led partnership that sought, over a period of 8 years, to enhance the profitability and sustainability of livestock enterprises by improving the connection between those producers, research and extension. Following a detailed survey, the research and extension needs of livestock producers were identified and several applied investigations were conducted to meet those needs and delivered through a range of extension activities. This final paper of the Cicerone Special Issue reflects on the entire Project from a wide array of perspectives, including livestock producers, researchers, extension specialists and staff employed by the Project, all of whom are authors of this paper. A notable early successful outcome of the Project was the improved precision of footrot diagnosis, which has been of value to the entire sheep industry, and that flowed from a field investigation of benign and virulent footrot combined with detailed genetic investigations, which led to an improved testing regime. This paper also reflects on the findings of an unreplicated agricultural ecosystem research trial, which measured the impact of pasture renovation, increased soil fertility and grazing management on the profitability and sustainability of three different 53-ha farmlets. Valuable findings from this whole-farmlet trial included the need for a high quality feed supply for increasing stocking rate and animal liveweights; the ability and utility of satellite imagery to detect changes in pasture growth, composition and recent grazing pressure; the value of short grazing and long rest periods for controlling Barber’s pole worms of sheep; the impact of increased stocking rates on whole-farm profitability and risk; methods of optimising decisions relating to pasture renovation, fertiliser applications and grazing management; and an integrated analysis of all key measured components of the farmlet management systems. Collectively, these findings were powerful as they were demonstrated at a scale credible to livestock producers using the ‘compare – measure – learn – adopt’ approach, which was the key philosophy adopted by the Cicerone Project. By comparing and measuring different whole-farm systems, and by ensuring that producers had ownership of the trial process, the Project successfully delivered objective findings that producers trusted and which increased our understanding of important drivers of complex grazing enterprises under variable climatic conditions. Some of these drivers included: the influence of soil phosphorus on botanical composition and subsequent livestock production, the role of pasture renovation and soil fertility on herbage supply, herbage quality and stocking rate, and the improved gastrointestinal nematode control delivered by intensive rotational grazing. The beneficiaries of the Project included the 180 farmer members who participated in some 61 field days and workshops; the research and extension collaborators including four postgraduates who completed their research investigations in conjunction with the Project; and some 500 undergraduate and 300 technical students who benefited from coming to understand the applied field comparisons of the three whole-farmlet systems. Having livestock producers play a significant leadership role led to valuable outcomes achieved with research collaborators; this should encourage the development of other learning partnerships which aim to explore complex farming system issues.

Delivering extension and adult learning outcomes from the Cicerone Project by ‘comparing, measuring, learning and adopting'

The Cicerone Project was a partnership between livestock producers, researchers and extension specialists on the Northern Tablelands of New South Wales, Australia that investigated several complex grazing enterprise issues between 1998 and 2006. It was conducted as a Participatory Action Research project, which first surveyed livestock producers to learn of their problems and then carried out investigations according to the Project’s chosen motto of ‘compare – measure – learn – adopt’. The Project included research into footrot diagnosis and an investigation of whole-farmlet livestock and pasture management systems complemented by a multi-faceted extension and education component, which delivered findings to a wide array of stakeholders across the Northern Tablelands and adjacent regions. This paper describes the extension and education methods and outcomes and reflects on how successful the engagement of livestock producers was through a partnership, which focussed on co-learning by all participants. Several different communication approaches were used including the production of 40 newsletters and the delivery of 61 field days. Collaborators also held two symposia, which presented comprehensive overviews of the research results. In the final year of the Project, a roadshow was held to communicate results to a wider audience in neighbouring districts. The results of the two footrot trials, which were conducted as Participatory Action Research projects, led to rapid and substantial changes in the testing regime for virulent footrot, resulting in large savings for livestock producers through more accurate detection of the disease. Other valued extension and industry outcomes were the ability to compare the biophysical and economic performance of different whole farmlets, an appreciation of the value of the whole-farm system approach, the trustworthiness of the results and the stimulation of livestock producers to think more deeply about their management systems, stocking rate and risk. The Project benefited from the research efforts of four postgraduate students and was of benefit to ~300 high school and technical college students and also some 500 university undergraduate students who undertook learning projects in conjunction with Project members and collaborators. This Special Issue of 24 journal papers represents a substantial delivery of the findings from this complex agroecosystem Project, which broke new ground in terms of securing much closer working relationships between livestock producers, scientists and extension specialists. Ultimately, this volume will allow extension of the results of the Cicerone Project to reach a wider audience than has typically been achieved through other Participatory Action Research projects.

Implanted renal replacement for end-stage renal disease

The nearly 400000 American patients on dialysis suffer high cardiovascular and infectious mortality, but there is now evidence that this morbid phenotype can be rescued by intensive dialytic therapy. Self-care dialysis at home is limited by patient fears about skill and safety. An implanted artificial kidney would provide the benefits of intensive therapy while avoiding the focal points of patient concern. Hollow fiber polymer membranes and dialytic waste removal are lifesaving innovations but are difficult to adapt to implantable therapies. Biomimetic membranes and living cells can replicate the native kidney's strategy for waste removal. Three key technology developments are necessary for implementation of an implantable artificial kidney: high efficiency ultrafiltration membranes, control of blood-materials interactions such as thrombosis and fouling, and stable differentiated function of renal proximal tubule cells in an engineered construct. There has been significant progress in demonstrating proof-of-concept experiments in each key technology area.

Solution self-assembly and adsorption at the air-water interface of the monorhamnose and dirhamnose rhamnolipids and their mixtures

The self-assembly in solution and adsorption at the air-water interface, measured by small-angle neutron scattering, SANS, and neutron reflectivity, NR, of the monorhamnose and dirhamnose rhamnolipids (R1, R2) and their mixtures, are discussed. The production of the deuterium-labeled rhamnolipids (required for the NR studies) from a Pseudomonas aeruginosa culture and their separation into the pure R1 and R2 components is described. At the air-water interface, R1 and R2 exhibit Langmuir-like adsorption isotherms, with saturated area/molecule values of about 60 and 75 Å(2), respectively. In R1/R2 mixtures, there is a strong partitioning of R1 to the surface and R2 competes less favorably because of the steric or packing constraints of the larger R2 dirhamnose headgroup. In dilute solution (<20 mM), R1 and R2 form small globular micelles, L(1), with aggregation numbers of about 50 and 30, respectively. At higher solution concentrations, R1 has a predominantly planar structure, L(α) (unilamellar, ULV, or bilamellar, BLV, vesicles) whereas R2 remains globular, with an aggregation number that increases with increasing surfactant concentration. For R1/R2 mixtures, solutions rich in R2 are predominantly micellar whereas solutions rich in R1 have a more planar structure. At an intermediate composition (60 to 80 mol % R1), there are mixed L(α)/L(1) and L(1)/L(α) regions. However, the higher preferred curvature associated with R2 tends to dominate the mixed R1/R2 microstructure and its associated phase behavior.

Mixing behavior of the biosurfactant, rhamnolipid, with a conventional anionic surfactant, sodium dodecyl benzene sulfonate

The use of small angle neutron scattering, SANS, neutron reflectivity, NR, and surface tension to study the mixing properties of the biosurfactant rhamnolipid with a conventional anionic surfactant, sodium dodecyl 6-benzene sulfonate, LAS, is reported. The monorhamnose rhamnolipid, R1, mixes close to ideally with LAS at the air-water interface, whereas for mixtures of LAS with the dirhamnose rhamnolipid, R2, the LAS strongly partitions to the air-water interface relative to R2, probably because of the steric hindrance of the larger R2 headgroup. These trends in the binary mixtures are also reflected in the ternary R1/R2/LAS mixtures. However, for these ternary mixtures, there is also a pronounced synergy in the total adsorption, which reaches a maximum for a LAS/rhamnolipid mole ratio of about 0.6 and a R1/R2 mol ratio of about 0.5, an effect which is not observed in the binary mixtures. In solution, the R1/LAS mixtures form relatively small globular micelles, L(1), at low surfactant concentrations (<20 mM), more planar structures (lamellar, L(α), unilamellar/multilamellar vesicles, ulv/mlv) are formed at higher surfactant concentrations for R1 and LAS rich compositions, and a large mixed phase (L(α)/L(1) and L(1)/L(α)) region forms at intermediate surfactant compositions. In contrast, for the R2/LAS mixtures, the higher preferred curvature of R2 dominates the phase behavior. The predominant microstructure is in the form of small globular micelles, except for solution compositions rich in LAS (>80 mol % LAS) where more planar structures are formed. For the ternary mixtures, there is an evolution in the resulting phase behavior from one dominated by L(1) (R2 rich) to one dominated by planar structures, L(α), (R1, LAS rich), and which strongly depends upon the LAS/rhamnolipid and R1/R2 mole ratio.

Lactic acid production by mixed cultures of Kluyveromyces marxianus, Lactobacillus delbrueckii ssp. bulgaricus and Lactobacillus helveticus

Lactic acid production using Kluyveromyces marxianus (IFO 288), Lactobacillus delbrueckii ssp. bulgaricus (ATCC 11842) and Lactobacillus helveticus (ATCC 15009) individually or as mixed culture on cheese whey in stirred or static fermentation conditions was evaluated. Lactic acid production, residual sugar and cell biomass were the main features examined. Increased lactic acid production was observed, when mixed cultures were used in comparison to individual ones. The highest lactic acid concentrations were achieved when K. marxianus yeast was combined with L. delbrueckii ssp. bulgaricus, and when all the strains were used revealing possible synergistic effects between the yeast and the two lactic acid bacteria. The same synergistic effects were further observed and verified when the mixed cultures were applied in sourdough fermentations, proving that the above microbiological system could be applied in the food fermentations where high lactic acid production is sought.

Whey-cheese production using freeze-dried kefir culture as a starter

AIMS

The aim of the present study was to evaluate the use of a freeze-dried kefir culture in the production of a novel type of whey-cheese similar to traditional Greek Myzithra-cheese, to achieve improvement of the quality characteristics of the final product and the extension of shelf-life.

METHODS AND RESULTS

The use of kefir culture as a starter led to increased lactic acid concentrations and decreased pH values in the final product compared with whey-cheese without starter culture. The effect of the starter culture on production of aroma-related compounds responsible for cheese flavour was also studied using the solid phase microextraction gas chromatography/mass spectrometry technique. Spoilage in unsalted kefir-whey-cheese was observed on the thirteenth and the twentieth day of preservation at 10 and 5 degrees C, respectively, while the corresponding times for unsalted whey-cheese preservation were 11 and 14 days.

CONCLUSIONS

The cheeses produced were characterized as high-quality products during the preliminary sensory evaluation. An indication of increased preservation time was attributed to the freeze-dried kefir culture, which also seemed to suppress growth of pathogens.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results suggested the use of kefir culture as a means to extend the shelf-life of dairy products with reduced or no salt content.

Characterization of a fungal strain isolated from a polyphenol polluted site

A group of fungal strains were isolated from a polyphenol polluted soil, taken from an olive oil processing plant in Attica, Greece. The fungi were tested for their ability to decolorize a polyaromatic dye Poly R-478, which was used as a model compound to test their ligninolytic activities. The strain K1.1 decolorized efficiently the dye on agar plates and was further studied. PCR amplification of the internal transcribed spacer (ITS) region of the ribosomal RNA genes from the genomic DNA isolated from mycelium grown in liquid culture resulted in amplified fragments. Via BLASTN search, the length of a 773 base pairs was identified as the basidiomycetes Coprinellus xanthothrix. The growth rates and the tolerance of the fungus were compared on solid media, containing four different concentrations of pentachlorophenol. Extracellular enzyme activities (lignin peroxidase, manganese peroxidase and laccase) were determined in defined liquid medium. The isolate expressed laccase and manganese peroxidase but not lignin peroxidase. The removal of the dye was also estimated in liquid medium. The fungus showed biosorption and biotransformation as removal mechanisms.

Use of Saccharomyces cerevisiae cells immobilized on orange peel as biocatalyst for alcoholic fermentation

A biocatalyst was prepared by immobilizing a commercial Saccharomyces cerevisiae strain (baker's yeast) on orange peel pieces for use in alcoholic fermentation and for fermented food applications. Cell immobilization was shown by electron microscopy and by the efficiency of the immobilized biocatalyst for alcoholic fermentation of various carbohydrate substrates (glucose, molasses, raisin extracts) and at various temperatures (30-15 degrees C). Fermentation times in all cases were low (5-15 h) and ethanol productivities were high (av. 150.6 g/ld) showing good operational stability of the biocatalyst and suitability for commercial applications. Reasonable amounts of volatile by-products were produced at all the temperatures studied, revealing potential application of the proposed biocatalyst in fermented food applications, to improve productivities and quality.

Effects of available nutrition and sire breeding values for growth and muscling on the development of crossbred lambs. 1: Growth and carcass characteristics

The growth and development of 387 crossbred lamb progeny from 9 Poll Dorset sires representing muscle (M), control (C), and growth (G) sire-types was studied. Sires were selected on the basis of their LAMBPLAN estimated breeding values (EBVs) for post-weaning growth (PWWT) and depth of loin muscle (PEMD). Lambs were provided with either LOW or HIGH levels of available grazing nutrition from 10 days of age onwards. Liveweight gain (LWG) throughout the study was less on LOW nutrition than on HIGH nutrition, leading to a 9.5 kg lower weaning liveweight (LW) and a 14.9 kg lower final LW in LOW lambs. After adjustment for final LW, HIGH lambs had significantly greater fat depth at the C-site (approximately 40 mm from the midline over the 12th rib) and tissue depth at the GR site (110 mm from the midline over the 12th rib) than did LOW lambs. This effect was consistent across sire-types. Depth of fat at the C-site was positively associated with the EBV of the sire for fat depth. The improvement in pre-weaning LWG, weaning weight, and final weight of lambs resulting from use of sires with a greater PWWT EBV was dependent upon the level of nutrition. This interaction was identified as different slopes (coefficients) for the regression between PWWT and trait for the 2 nutrition levels, indicating that the expression of the sire’s genetic potential for growth at these times was significantly moderated by nutrition. The additional depth of lamb loin muscle resulting from use of sires of higher PEMD EBV was consistent across both LOW and HIGH nutrition treatments, with 1 mm of PEMD leading to a 0.6-mm increase in loin depth. Other consequences of sires having a high genetic capacity for loin muscle depth were reduced carcass C-fat depth with increasing sire PEMD and a tendency for conformation score to improve with the PEMD of the sire. The wool-growth response to improved nutrition was less in M lambs than in lambs of other sire-types, suggesting a difference in priority for protein partitioning between muscle and wool in lambs differing in genetic propensity for muscle growth.

Biodegradation of lindane by Pleurotus ostreatus via central composite design

The degradation of lindane was studied in liquid-agitated cultures using a commercial strain of the fungus Pleurotus ostreatus as the biodegrading organism. The biodegradation was accomplished with the action of extracellular oxidative enzymes, produced by the fungus to decompose woody substrates. Enzyme activities of manganese peroxidase and laccase were measured in a liquid mineral medium. An orthogonal Central Composite Design of experiments was used to construct second-order response surfaces with the fungus growth, final pH and the lindane biodegradation as optimization parameters. The initial lindane concentration, the nitrogen content, the incubation time and the temperature were used as design factors. Optimal conditions found for all these parameters will be used for the continuation of this project aiming at the bioremediation of contaminated sites with persistent organic pollutants such as lindane.

Distribution and molecular investigation of highly thermophilic bacteria associated with cool soil environments

In this study, both molecular and culture-based methods were used to characterize thermophilic bacteria associated with the subsurface soil environment in Northern Ireland. A total of 53 thermophilic, aerobic, sporulating and non-sporulating bacteria were isolated from subsurface soil samples obtained from two sites. They were screened by amplified ribosomal DNA restriction analysis prior to 16 S rRNA gene sequencing. The majority of the sequences were associated with Geobacillus thermoleovorans (50%) and Geobacillus caldoxylosilyticus (34.6%). Isolates F10, F20 and Tf exhibited only 93% similarity with Geobacillus toebii strain F70. Hence they may represent a new species of the genus Geobacillus.

Habitat, applications and genomics of the aerobic, thermophilic genus Geobacillus

Thermophilic bacteria belonging to Bacillus genetic group 5 have been reclassified as being members of Geobacillus gen. nov., with G. stearothermophilus as the type strain. Geobacillus species, literally meaning earth or soil Bacillus, are widely distributed and readily isolated from natural and man-made thermophilic biotopes. Work within our group has however shown that an abundance of genetically distinct Geobacillus isolates can be obtained from temperate Irish soils. As with many thermophiles there is considerable interest in potential industrial application of these bacteria and their gene products. This review describes two novel applications for Geobacillus isolates, firstly in the metabolism of the herbicide glyphosate and secondly in the metabolism of quorum-sensing signal molecules from Gram-negative bacteria. Finally the current state of the art is described for Bacillus genomics, with details given of three independent genome-sequencing projects of Geobacillus isolates.

High-Temperature Wine Making Using the Thermotolerant Yeast Strain Kluyveromyces marxianus IMB3

Kluyveromyces marxianus IMB3 yeast cells were immobilized on delignified cellulosic material, apple, and quince separately. Both immobilized and free cells were used in high-temperature wine making, and their fermented grape must contained 3 to 4% alcohol. Semisweet wines were produced by the addition of potable alcohol to the fermented must. Preliminary sensory evaluation of the produced semisweet wines showed good flavor and aroma. The final product contained extremely low levels of higher and amyl alcohols while ethyl acetate was at levels usually present in wines. The ferment produced may be blended with other products to improve their quality.

Factors affecting the genetic engineering of plants by microprojectile bombardment

Since its development in the mid-1980s, microprojectile bombardment has been widely employed as a method for direct gene transfer into a wide range of plants, including the previously difficult-to-transform monocotyledonous species. Although the numerous instruments available for microprojectile-mediated gene delivery and their applications have been widely discussed, less attention has been paid to the critical factors which affect the efficiency of this method of gene delivery. In this review we do not wish to describe the array of devices used for microprojectile delivery or their uses which have already been definitively described, but instead wish to report on research developments investigating the factors which affect microprojectile-mediated transformation of plants.

Enhanced bioremediation of n-alkane in petroleum sludge using bacterial consortium amended with rhamnolipid and micronutrients

The purpose of the present study was to investigate possible methods to enhance the rate of biodegradation of oil sludge from crude oil tank bottom, thus reducing the time usually required for bioremediation. Enhancement of biodegradation was achieved through bioaugmentation and biostimulation. About 10% and 20% sludge contaminated sterile and non-sterile soil samples were treated with bacterial consortium (BC), rhamnolipid biosurfactant (RL) and nitrogen, phosphorus and potassium (NPK) solution. Maximum n-alkane degradation occurred in the 10% sludge contaminated soil samples. The effects of treatment carried out with the non-sterile soil samples were more pronounced than in the sterile soils. Maximum degradation was achieved after the 56th day of treatment. n-Alkanes in the range of nC8-nC11 were degraded completely followed by nC12-nC21, nC22-nC31 and nC32-nC40 with percentage degradations of 100%, 83-98%, 80-85% and 57-73% respectively. Statistical analysis using analysis of variance and Duncan's multiple range test revealed that the level of amendments, incubation time and combination of amendments significantly influenced bacterial growth, protein concentration and surface tension at a 1% probability level. All tested additives BC, NPK and RL had significant positive effects on the bioremediation of n-alkane in petroleum sludge.

Grape and apple wines volatile fermentation products and possible relation to spoilage

The main volatile by-products of the alcoholic fermentation of grape wine, cider and apple pulp wine were investigated to determine if any correlated with spoilage resistance in the latter two. Spoilage was visually detected after seven days in low-alcohol grape wine in comparison to 11 and 16 days in cider and apple pulp wine, respectively. Acetaldehyde, ethyl acetate, methanol, propanol, isobutanol and amyl alcohols were the main fermentation by-products detected in all three wines. There were highest concentrations of acetaldehyde, ethyl acetate, methanol and propanol in grape wine and, therefore, these by-products could not be implicated in spoilage resistance in apple wines. Increased concentrations of isobutanol and amyl alcohols, however, in cider and apple pulp wine in comparison to grape wine might have been the reason for spoilage resistance in the apple wines.

Resolution of (RS)-proglumide using lipase from Candida cylindraceae

Proglumide is used in the treatment of neuropathic pain. It acts by inhibiting peptide cholecystokinin (CCK). Neural injury produces an elevation in plasma CCK. Proglumide has been also shown to augment the analgesic effect of sustained release morphine in neuropathic pain. Currently proglumide is administered as a racemic mixture. In the present study, an attempt is made to separate the racemic mixture of the drug using lipase obtained from Candida cylindracea by stereoselective esterification. Enzymatic stereoselective esterification was carried out in organic solvents. The resolution was studied using a chromatographic column with a chiral support and mass spectrometry. The reaction conditions for stereoselective esterification including amount of substrate, amount of enzyme, alcohol, solvent and temperature were optimised during the present investigation. Butanol and hexanol were found to be suitable for formation of S and R esters, respectively. Hexane was the best solvent for esterification and the optimum temperature was found to be 30 degreesC.

Continuous whey fermentation using kefir yeast immobilized on delignified cellulosic material

Delignified cellulosic-supported biocatalyst, prepared by immobilization of kefir yeast on delignified cellulosic material (DCM), was found to be suitable for continuous, modified whey fermentation. The modified whey contained 1% raisin extract and molasses. Ethanol productivities ranged from 3.6 to 8.3 g L(-1)day(-1), whereas parameters such as ethanol concentration, residual sugars, and daily fermented whey productivity were acceptable for the production of potable alcohol and alcoholic drinks in industrial fermentations. The continuous fermentation bioreactor was operated for 39 days, stored for 18 days at 4 degrees C, and operated again for another 15 days without any diminution of the ethanol productivity. The concentrations of higher alcohols (propanol-1, isobutyl alcohol, and amyl alcohols) were low. The main volatile byproducts formed in the continuous process were similar to those observed in alcoholic beverages, and the fermented whey had a good aroma. The concentrations of higher alcohols were very low when compared to that of ethyl acetate, therefore resulting in a quality product. The possibility of using such a process for the production of potable alcohol or a novel, low-alcohol content drink is proposed.

High-temperature alcoholic fermentation of whey using Kluyveromyces marxianus IMB3 yeast immobilized on delignified cellulosic material

A novel system for high-temperature alcoholic fermentation of whey is described. This system consists of Kluyveromyces marxianus yeast immobilized on delignified cellulosic material (DCM). The effect of pH, initial lactose concentration and temperature on the fermentation of a synthetic medium containing lactose was studied. Batch fermentations of whey were also carried out and the formation of volatile by-products was examined. The concentrations of higher alcohols were found to be in very low levels leading to a product of improved quality. The fermented whey had an improved characteristic aroma compared to unfermented whey. The possibility to use fermented whey as raw material for the production of a novel, low alcohol content drink was also investigated.

Improving the quality of industrially important enzymes by directed evolution

Directed evolution is a new process for developing industrially viable biocatalysts. This technique does not require a comprehensive knowledge of the relationships between sequence structure and function of proteins as required by protein engineering. It mimics the process of Darwinian evolution in a test tube combining random mutagenesis and recombination with screening or selection for enzyme variants that have the desired properties. Directed evolution helps in enhancing the enzyme performance both in natural and synthetic environments. This article reviews the process of directed evolution and its application to improve substrate specificity, activity, enantioselectivity and thermal stability.

Chromatographic method for diaminopimelic acid detection in calcareous rocks. Presence of a bacterial biomarker in stromatolites

The presence in the environment of diaminopimelic acid (DAP), a specific eubacterial marker, can be attributed to that of bacteria. We report a reliable and highly sensitive method for the quantification of DAP in calcareous rocks. It consists of acid hydrolysis of rock powder, purification of DAP by chromatography on Dowex 50W and Spherogel AA-NA+ columns, and quantitative analysis by high-performance liquid chromatography. Addition of tritiated DAP, the internal standard, allows one to follow the relevant fractions throughout the purification procedure and to determine their yield. The analytical step consists in pre-column derivatization with ortho-phthaldialdehyde of purified samples, and separation through a reversed-phase C18 column. Chemical controls, i.e., oxidation of samples to rule out the presence of co-eluting lanthionine and cystathionine, as well as mass spectrometry, confirm the presence of DAP in analyzed samples. Our method allows the separation of meso- from L- and/or D-stereoisomers of DAP, and reveals their presence in the examined rocks, two stromatolites of different age and geographic origin.

Microbial decolourisation and degradation of textile dyes

Dyes and dyestuffs find use in a wide range of industries but are of primary importance to textile manufacturing. Wastewater from the textile industry can contain a variety of polluting substances including dyes. Increasingly, environmental legislation is being imposed to control the release of dyes, in particular azo-based compounds, into the environment. The ability of microorganisms to decolourise and metabolise dyes has long been known, and the use of bioremediation based technologies for treating textile wastewater has attracted interest. Within this review, we investigate the mechanisms by which diverse categories of microorganisms, such as the white-rot fungi and anaerobic bacterial consortia, bring about the degradation of dyestuffs.