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BACKGROUND/AIMS: Signaling and metabolic perturbations contribute to dysregulated skeletal muscle protein homeostasis and secondary sarcopenia in response to a number of cellular stressors including ethanol exposure. Using an innovative multiomics-based curating of unbiased data, we identified molecular and metabolic therapeutic targets and experimentally validated restoration of protein homeostasis in an ethanol-fed mouse model of liver disease. METHODS: Studies were performed in ethanol-treated differentiated C2C12 myotubes and physiological relevance established in an ethanol-fed mouse model of alcohol-related liver disease (mALD) or pair-fed control C57BL/6 mice. Transcriptome and proteome from ethanol treated-myotubes and gastrocnemius muscle from mALD and pair-fed mice were analyzed to identify target pathways and molecules. Readouts including signaling responses and autophagy markers by immunoblots, mitochondrial oxidative function and free radical generation, and metabolic studies by gas chromatography-mass spectrometry and sarcopenic phenotype by imaging. RESULTS: Multiomics analyses showed that ethanol impaired skeletal muscle mTORC1 signaling, mitochondrial oxidative pathways, including intermediary metabolite regulatory genes, interleukin-6, and amino acid degradation pathways are β-hydroxymethyl-butyrate targets. Ethanol decreased mTORC1 signaling, increased autophagy flux, impaired mitochondrial oxidative function with decreased tricarboxylic acid cycle intermediary metabolites, ATP synthesis, protein synthesis and myotube diameter that were reversed by HMB. Consistently, skeletal muscle from mALD had decreased mTORC1 signaling, reduced fractional and total muscle protein synthesis rates, increased autophagy markers, lower intermediary metabolite concentrations, and lower muscle mass and fiber diameter that were reversed by β-hydroxymethyl-butyrate treatment. CONCLUSION: An innovative multiomics approach followed by experimental validation showed that β-hydroxymethyl-butyrate restores muscle protein homeostasis in liver disease.

B cells produce high-affinity immunoglobulins (Igs), or antibodies, to eliminate foreign pathogens. Mature, naïve B cells expressing an antigen-specific cell surface Ig, or B cell receptor (BCR), are directed toward either an extrafollicular (EF) or germinal center (GC) response upon antigen binding. B cell interactions with CD4+pre-T follicular helper (pre-Tfh) cells at the T-B border and effector Tfh cells in the B cell follicle and GC control B cell development in response to antigen. Here, we review recent studies demonstrating the role of B cell receptor (BCR) affinity in modulating T-B interactions and the subsequent differentiation of B cells in the EF and GC response. Overall, these studies demonstrate that B cells expressing high affinity BCRs preferentially differentiate into antibody secreting cells (ASCs) while those expressing low affinity BCRs undergo further affinity maturation or differentiate into memory B cells (MBCs).

Ammonia is a cytotoxic molecule generated during normal cellular functions. Dysregulated ammonia metabolism, which is evident in many chronic diseases such as liver cirrhosis, heart failure, and chronic obstructive pulmonary disease, initiates a hyperammonemic stress response in tissues including skeletal muscle and in myotubes. Perturbations in levels of specific regulatory molecules have been reported, but the global responses to hyperammonemia are unclear. In this study, we used a multiomics approach to vertically integrate unbiased data generated using an assay for transposase-accessible chromatin with high-throughput sequencing, RNA-Seq, and proteomics. We then horizontally integrated these data across different models of hyperammonemia, including myotubes and mouse and human muscle tissues. Changes in chromatin accessibility and/or expression of genes resulted in distinct clusters of temporal molecular changes including transient, persistent, and delayed responses during hyperammonemia in myotubes. Known responses to hyperammonemia, including mitochondrial and oxidative dysfunction, protein homeostasis disruption, and oxidative stress pathway activation, were enriched in our datasets. During hyperammonemia, pathways that impact skeletal muscle structure and function that were consistently enriched were those that contribute to mitochondrial dysfunction, oxidative stress, and senescence. We made several novel observations, including an enrichment in antiapoptotic B-cell leukemia/lymphoma 2 family protein expression, increased calcium flux, and increased protein glycosylation in myotubes and muscle tissue upon hyperammonemia. Critical molecules in these pathways were validated experimentally. Human skeletal muscle from patients with cirrhosis displayed similar responses, establishing translational relevance. These data demonstrate complex molecular interactions during adaptive and maladaptive responses during the cellular stress response to hyperammonemia.

Despite significant advances in cancer treatment, the prognosis for oral cancer remains poor in comparison to other cancer types, including breast, skin, and prostate. As a result, more effective therapeutic modalities are needed for the treatment of oral cancer. Consequently, in the present study, we examined the feasibility of using a dual peptide carrier approach, combining an epidermal growth factor receptor (EGFR)-targeting peptide with an endosome-disruptive peptide, to mediate targeted delivery of small interfering RNAs (siRNAs) into EGFR-overexpressing oral cancer cells and induce silencing of the targeted oncogene, cancerous inhibitor of protein phosphatase 2A (CIP2A).Fluorescence microscopy, real-time PCR, Western blot analysis, and in vivo bioimaging of mice containing orthotopic xenograft tumors were used to examine the ability of the dual peptide carrier to mediate specific delivery of bioactive siRNAs into EGFR-overexpressing oral cancer cells/tissues.Co-complexation of the EGFR-targeting peptide, GE11R9, with the endosome-disruptive 599 peptide facilitated the specific uptake of siRNAs into oral cancer cells overexpressing EGFR in vitro with optimal gene silencing observed at a 60:30:1 (GE11R9:599:siRNA) molar ratio. Furthermore, when administered systemically to mice bearing xenograft oral tumors, this dual peptide complex mediated increased targeted delivery of siRNAs into tumor tissues in comparison to the 599 peptide alone and significantly enhanced CIP2A silencing.Herein we provide the first report demonstrating the clinical potential of a dual peptide strategy for siRNA-based therapeutics by synergistically mediating the effective targeting and delivery of bioactive siRNAs into EGFR-overexpressing oral cancer cells.

Interest in dual nitrogen expander liquefaction technology for floating liquefied natural gas (FLNG) applications is driven by the following factors: inflammable refrigerantsimplicitylow weightno refrigerant sloshing or maldistribution due to motionquick start-upeasy adjustment for changing feed conditions The downside is that dual nitrogen expander technology offers significantly lower liquefaction efficiency than competing FLNG technologies. The proper selection and sizing of the upstream gas treating and liquefaction system is critical during Front End Engineering Design (FEED) to ensure that the system footprint, weight and center-of-gravity is appropriately estimated as this effects the sizing, design and performance of the floating hull. This paper will demonstrate how the process design can be optimized over a range of feed compositions or conditions if some flexibility is built into the liquefaction heat exchange during design. This preserves flexibility as a key advantage of the technology. The intent is to reduce process inefficiencies and promote competitiveness with other technologies. Note that there are many different nitrogen expander technology configurations available in the market. The configuration used here is generic and used to demonstrate the optimization concept. With 10 independent variables and coupling between the variables, this optimization is difficult to perform using simple manual methods. Therefore we will employ a coupled simulation-optimization method. This paper also provides insight to the application of coupled simulation-optimization to problems, as illustrated by the specific application to a dual titrogen expander technology. Although this method is applicable to the initial design of liquefaction processes, the focus here is on off-design optimization of the facility later in the design cycle and in operation. This optimization methodology is shown to provide benefits beyond the initial process design, extending into the operation of the facility. The methodology does not rely upon a specific tool set and there are non-academic tools that support this approach.

The protozoan parasite responsible for human amoebiasis is Entamoeba histolytica. An important facet of the life cycle of E. histolytica involves the conversion of the mature trophozoite to a cyst. This transition is thought to involve homologous recombination (HR), which is dependent upon the Rad51 recombinase. Here, a biochemical characterization of highly purified ehRad51 protein is presented. The ehRad51 protein preferentially binds ssDNA, forms a presynaptic filament and possesses ATP hydrolysis activity that is stimulated by the presence of DNA. Evidence is provided that ehRad51 catalyzes robust DNA strand exchange over at least 5.4 kilobase pairs. Although the homologous DNA pairing activity of ehRad51 is weak, it is strongly enhanced by the presence of two HR accessory cofactors, calcium and Hop2-Mnd1. The biochemical system described herein was used to demonstrate the potential for targeting ehRad51 with two small molecule inhibitors of human RAD51. We show that 4,4′-diisothiocyanostilbene-2,2′-disulfonic acid (DIDS) inhibited ehRad51 by interfering with DNA binding and attenuated encystation in Entamoeba invadens, while B02 had no effect on ehRad51 strand exchange activity. These results provide insight into the underlying mechanism of homology-directed DNA repair in E. histolytica.

Microbial growth in heating ventilation and air-conditioning (HVAC) systems with the subsequent contamination of indoor air is of increasing concern. Microbes and the subsequent biofilms grow easily within heat exchangers. A comparative study where heat exchangers fabricated from antimicrobial copper were evaluated for their ability to limit microbial growth was conducted using a full-scale HVAC system under conditions of normal flow rates using single-pass outside air. Resident bacterial and fungal populations were quantitatively assessed by removing triplicate sets of coupons from each exchanger commencing the fourth week after their installation for the next 30 weeks. The intrinsic biofilm associated with each coupon was extracted and characterized using selective and differential media. The predominant organisms isolated from aluminum exchangers were species of Methylobacterium of which at least three colony morphologies and 11 distinct PFGE patterns we found; of the few bacteria isolated from the copper exchangers, the majority were species of Bacillus. The concentrations and type of bacteria recovered from the control, aluminum, exchangers were found to be dependent on the type of plating media used and were 11,411-47,257 CFU cm(-2) per coupon surface. The concentration of fungi was found to average 378 CFU cm(-2). Significantly lower concentrations of bacteria, 3 CFU cm(-2), and fungi, 1 CFU cm(-2), were recovered from copper exchangers regardless of the plating media used. Commonly used aluminum heat exchangers developed stable, mixed, bacterial/fungal biofilms in excess of 47,000 organisms per cm(2) within 4 weeks of operation, whereas the antimicrobial properties of metallic copper were able to limit the microbial load affiliated with the copper heat exchangers to levels 99.97 % lower during the same time period.

Steatotic livers are sensitive to ischemic events and associated ATP depletion. Hepatocellular necrosis following these events may result from mitochondrial uncoupling protein-2 (UCP2) expression. To test this hypothesis, we developed a model of in vitro steatosis using primary hepatocytes from wild-type (WT) and UCP2 knockout (KO) mice and subjected them to hypoxia/reoxygenation (H/R). Using cultured hepatocytes treated with emulsified fatty acids for 24 h, generating a steatotic phenotype (i.e., microvesicular and broad-spectrum fatty acid accumulation), we found that the phenotype of the WT and UCP2 KO were the same; however, cellular viability was increased in the steatotic KO hepatocytes following 4 h of hypoxia and 24 h of reoxygenation; Hepatocellular ATP levels decreased during hypoxia and recovered after reoxygenation in the control and UCP2 KO steatotic hepatocytes but not in the WT steatotic hepatocytes; mitochondrial membrane potential in WT and UCP2 KO steatotic groups was less than control groups but higher than UCP2 KO hepatocytes. Following reoxygenation, lipid peroxidation, as measured by thiobarbituric acid reactive substances, increased in all groups but to a greater extent in the steatotic hepatocytes, regardless of UCP2 expression. These results demonstrate that UCP2 sensitizes steatotic hepatocytes to H/R through mitochondrial depolarization and ATP depletion but not lipid peroxidation.

Meiosis depends on homologous recombination (HR) in most sexually reproducing organisms. Efficient meiotic HR requires the activity of the meiosis-specific recombinase, Dmc1. Previous work shows Dmc1 is expressed in Entamoeba histolytica, a eukaryotic parasite responsible for amoebiasis throughout the world, suggesting this organism undergoes meiosis. Here, we demonstrate Dmc1 protein is expressed in E. histolytica. We show that purified ehDmc1 forms presynaptic filaments and catalyzes ATP-dependent homologous DNA pairing and DNA strand exchange over at least several thousand base pairs. The DNA pairing and strand exchange activities are enhanced by the presence of calcium and the meiosis-specific recombination accessory factor, Hop2-Mnd1. In combination, calcium and Hop2-Mnd1 dramatically increase the rate of DNA strand exchange activity of ehDmc1. The biochemical system described herein provides a basis on which to better understand the role of ehDmc1 and other HR proteins in E. histolytica.

The effects of chronic nicotine on the behavioral performance of young (4 month) and old (24 month) Fischer-344 rats were assessed on four behavioral tasks: activity chamber, rotating rod, serial pattern learning, and Morris water maze paradigm. Old and young nicotine-treated rats received an intraperitoneal injection of nicotine (0.20 mg/kg) 15 min prior to all behavioral testing, and old and young saline-treated rats received saline injections 15 min prior to all behavioral testing. Nicotine improved motor coordination and increased the general activity levels of the old rats compared to old saline-treated rats. There were no significant differences in the behaviors of the young rats in these behavioral evaluations. In young rats, nicotine improved the acquisition of a serial pattern, suggesting an improvement in working memory or related processes. Nicotine was found to increase swim speed in a Morris water maze paradigm with a hidden platform; however, no beneficial effects of nicotine in reference memory were obtained for either age group. These results suggests that nicotine may not be as beneficial in attenuating age-related learning and memory deficits as once proposed.

Despite a better understanding of the pathogenesis of oral cancer, its treatment outcome remains poor. Thus, there is a need for new therapeutic strategies to improve the prognosis of this disease. RNA interference (RNAi) appears to be a promising therapeutic tool for the treatment of many diseases, including oral cancer. However, an obstacle for RNAi-mediated therapies has been delivery, in particular, the retention of small interfering RNAs (siRNAs) in endosomes and their subsequent degradation in lysosomes, resulting in inefficient gene silencing. Thus, the current study examined the feasibility of designing and utilizing a peptide, termed 599, consisting of a synthetic influenza virus-derived endosome-disruptive fusogenic peptide sequence and a stretch of cationic cell-penetrating nona(D-arginine) residues, to deliver siRNAs into oral cancer cells and induce silencing of the therapeutic target, CIP2A, an oncoprotein overexpressed in various human malignancies including oral cancer. Increasing the 599 peptide-to-siRNA molar ratio demonstrated a higher binding capacity for siRNA molecules and enhanced siRNA delivery into the cytoplasm of oral cancer cells. In fact, quantitative measurements of siRNA delivery into cells demonstrated that a 50∶1 peptide-to-siRNA molar ratio could deliver 18-fold higher amounts of siRNAs compared to cells treated with siRNA alone with no significant long-term cytotoxic effects. Most importantly, the 599 peptide-mediated siRNA delivery promoted significant CIP2A mRNA and protein silencing which resulted in decreased oral cancer cell invasiveness and anchorage-independent growth. Together, these data demonstrate that a chimeric peptide consisting of a fusogenic sequence, in combination with cell-penetrating residues, can be used to effectively deliver siRNAs into oral cancer cells and induce the silencing of its target gene, potentially offering a new therapeutic strategy in combating oral cancer.

Cleaning is an effective way to lower the bacterial burden (BB) on surfaces and minimize the infection risk to patients. However, BB can quickly return. Copper, when used to surface hospital bed rails, was found to consistently limit surface BB before and after cleaning through its continuous antimicrobial activity.

A bacterium coded as strain HAP-1 was isolated from a municipal anaerobic digestor for its ability to reduce >7000 ppm perchlorate in wastewaters. The organism is capable of the dissimilatory reduction of perchlorate on chlorate to chloride for energy and growth. It is a Gram-negative, non-sporeforming, obligately anaerobic, motile thin rod. Antibiotic resistance, utilization of carbon substrates and utilization of electron acceptors by bacterium HAP-1 were similar toWolinella succinogenes. The organism's 16S rRNA sequence was 0.75% different from that of the type strain ofW. succinogenes. The fatty acid compositions of the two organisms are very similar. The morphological, physiological and 16S rRNA sequence data indicated that bacterium HAP-1 is a strain ofW. succinogenes that can utilize perchlorate or chlorate as a terminal electron acceptor.

Caribbean fruit fly, Anastrepha suspensa (Loew), males and females were given the choice Nu-Lure + sugar and water + sugar. The most active visitation periods were 0800-0830, 1300-1330, and 1600-1630 hours for Nu-Lure + sugar, and 0800-0830 hours for water + sugar. Female visits to food lures were ≈1.5 times male activity overall, but on only a few days could those female visits be statistically validated. Starved males visited water + sugar more than Nu-Lure + sugar at age 5 d. Fed flies displayed little or no pattern of feeding activity from 3-16 d old. Starved flies had peaks of visits to water + sugar for males on days 5. 6. 13, and 14, and females visits to Nu-Lure + sugar on days 8 and 9. Visitations to food lures by starved and fed females were mirrored by egg production. We conclude that A. suspensa has an absolute protein requirement for egg production.

Two major hurdles for small interfering RNA (siRNA)-mediated therapies are cell/tissue-type targeted delivery and endosomal entrapment of siRNAs, resulting in inefficient gene silencing. As a result, the objective of this study was to examine the feasibility of utilizing two peptides, one with cancer cell-targeting specificity and the second with endosome-disruptive properties, to co-deliver bioactive siRNAs into oral cancer cells overexpressing the epidermal growth factor receptor (EGFR) and induce silencing of the targeted oncoprotein, CIP2A. Previously, we designed a novel endosome-disruptive peptide, termed 599, that was demonstrated to mediate intracellular delivery of bioactive siRNAs targeting CIP2A (siCIP2A) in vitro. Furthermore, we recently demonstrated that 599 peptide-mediated delivery of siCIP2A into tumor tissues via intratumoral injections reduced the expression of CIP2A and significantly inhibited tumor growth. In order to induce targeted uptake via systemic administration, we designed the EGFR targeting peptide, GE11R9, which was found to deliver siRNAs specifically to EGFR-overexpressing oral cancer cells; however, it was incapable of mediating the delivery of bioactive siRNAs due to endosomal entrapment. Consequently, we developed a novel dual peptide delivery strategy, combining the 599 peptide, with the GE11R9 peptide and examined their ability to co-deliver siRNAs. Our results demonstrated that the dual peptide complex exhibited effective binding and specific uptake of siRNAs into EGFR-overexpressing cells compared to low-EGFR-expressing cells. The co-addition of the 599 peptide with the GE11R9 peptide also restored siRNA functionality. Furthermore, when administered systemically to mice bearing xenograft oral tumors, the dual peptide complex mediated increased targeted delivery of siRNAs into tumor tissues in comparison to the 599 peptide alone. Together, these data demonstrate the clinical potential of the dual peptide strategy for RNAi-based therapeutics by synergistically mediating the effective targeting and delivery of bioactive siRNAs into EGFR-overexpressing cancer cells. Citation Format: Angela A. Alexander-Bryant, Haiwen Zhang, William Pugh, Lu Dinh, Christopher Attaway, Laurence Eggart, Robert Sansevere, Liliana Cantini, Andrew Jakymiw. Dual peptide-mediated targeted delivery of siRNAs for the treatment of oral cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2057.

General methods for testing effects of toxicants on Ana stepha suspense (Loew) (Caribbean fruit fly) are described. We estimated relative toxicities of topically applied methamidophos, malathion, ethion, and acephate and orally administered dimethoate, methamidophos, phosdrin, acephate, malathion, and chlorpyrifos for a laboratory colony of A. suspense . Females were significantly more tolerant to malathion than males by oral administration but not by topical application. Other pesticides were not differentially toxic to sexes.

A mixed bacterial culture capable of reducing perchlorate stoichiometrically to chloride under naerobic conditions was enriched from municipal digester sludge. The reduction of 10 mM perchlorate resulted in oxidation of the medium and cessation of perchlorate reduction. The activity was recovered on addition of a reducing agent. Addition of air to the culture during perchlorate reduction immediately terminated the process and aeration for 12 h permanently destroyed the ability of the culture to reduce perchlorate. The culture also reduced nitrite, nitrate, chlorite, chlorate and sulfate. The presence of 10 mM nitrite or chlorite completely inhibited perchlorate reduction, whereas the same concentration of chlorate decreased the reduction rate. Nitrate or sulfate did not affect perchlorate reduction. Chlorate and chlorite, suspected intermediates in the reduction of perchlorate to chloride, were not detected in any cultures during reduction of perchlorate.

Abstract Unconventional gas reservoirs, including tight gas, shale gas and coalbed methane, are becoming a critically important component of the current and future gas supply. However, these reservoirs often present unique stimulation challenges. The use of water-based fracturing fluids in low permeability reservoirs may result in loss of effective frac half-length caused by phase trapping associated with the retention of the introduced water into the formation. This problem is increased by the water-wet nature of most tight gas reservoirs (where no initial liquid hydrocarbon saturation is, or ever has been, present) because of the strong spreading coefficient of water in such a situation. The retention of increased water saturation in the pore system can restrict the flow of produced gaseous hydrocarbons such as methane. Capillary pressures of 10 to 20 MPa or higher can be present in low permeability formations at low water saturation levels. The inability to generate sufficient capillary drawdown force using the natural reservoir drawdown pressure can result in extended fluid recovery times, or permanent loss of effective fracture half-length. Furthermore, use of water in subnormally saturated reservoirs may also reduce permeability and associated gas flow through a permanent increase in water saturation of the reservoir. Secondary costs, such as rig time for swabbing, can add to the negative economic impact. Gelled liquid petroleum gas-based fracturing fluids are designed to address phase trapping concerns by replacement of water with a mixture of liquid petroleum gas (LPG) and a volatile hydrocarbon fluid. Once the well is drawn down for flowback, some of the LPG portion of the fluid may be produced back as a gas, dependent upon temperature and pressure. The remaining LPG remains dissolved in the hydrocarbon fluid and is produced back as a miscible mixture using a methane drive mechanism. By eliminating water and having LPG as up to 80 - 90% of the total fluid system, cleanup is greatly facilitated, even in wells having very low permeability and reservoir pressure. The effects of fracturing fluid retention on gas flow in the fracture face can be as important as fracture conductivity when designing a treatment. It is possible to have a conductive fracture with good half-length in the desired productive zone and still not realize economic or optimum gas production if phase trapping and/or relative permeability effects are restricting gas flow. Description Gelled LPG-based fracturing fluids are a unique hydrocarbon-based fracturing fluid system designed for gas well stimulation. They use up to 100% gelled LPG for the pad and flush. The sand slurry stages use a mixture of up to 90% LPG with the balance of the volume being a volatile hydrocarbon-based fluid. All chemicals and proppant are added to the base fluid at the blender. LPG, which composes the balance of the downhole fluid volume, is injected at the wellhead where it forms one miscible mixture with the base oil. It is important to note that under pumping pressures, this is a single-phase gelled fluid system, similar to gelled oil in rheology, friction pressures, proppant transport and leakoff control.

Endocytosis is an important virulence function for Entamoeba histolytica, the causative agent of amoebic dysentery. Although a number of E. histolytica proteins that regulate this process have been identified, less is known about the role of lipids. In other systems, phosphatidylinositol 3-phosphate (PI3P), a product of phosphatidylinositol 3-kinase (PI 3-kinase), has been shown to be required for endocytosis. FYVE-finger domains are protein motifs that bind specifically to PI3P. Using a PI3P biosensor consisting of glutathione-S-transferase (GST) fused to two tandem FYVE-finger domains, we have localized PI3P to phagosomes but not fluid-phase pinosomes in E. histolytica, suggesting a role for PI3P in phagocytosis. Treatment of cells with PI 3-kinase inhibitors impaired GST-2 x FYVE-phagosome association supporting the authenticity of the biosensor staining. However, treatment with PI 3-kinase inhibitors did not inhibit E. histolytica-particle interaction, indicating that PI3P is not required for the initial step, but is required for subsequent steps of phagocytosis.

A co-culture of two Pseudomonas putida isolates was enriched from sediment on a mixture of benzene, toluene, ethylbenzene, m-xylene, p-xylene, and o-xylene. The co-culture readily degraded each of the compounds present. Benzene, toluene, and ethylbenzene were used as growth substrates by one isolate, while toluene, m-xylene, and p-xylene were used as growth substrates by the other. Neither isolate could grow on o-xylene, but it was removed in the presence of the other compounds presumably by co-metabolism. The findings presented here support other reports in which constructed communities were effectively used to degrade blends of between two and four of the components of BTEX. However, here the co-culture of two P. putida isolates effectively degraded a complete BTEX stream containing all six of the components.

The biotreatment of complex mixtures of volatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene, and xylene isomers (BTEX) has been investigated by many workers. However, the majority of the work has dealt with the treatment of aqueous or soil phase contamination. The biological treatment of gas and vapor phase sources of VOC wastes has recently received attention with increased usage of biofilters and bioscrubbers. Although these systems are relatively inexpensive, performance problems associated with biomass plugging, gas channeling, and support media acidification have limited their adoption. In this report we describe the development and evaluation of an alternative biotreatment system that allows rapid diffusion of both BTEX and oxygen through a silicone membrane to an active biofilm. The bioreactor system has a rapid liquid recycle, which facilitates nutrient medium mixing over the biofilm and allows for removal of sloughing cell mass. The system removed BTEX at rates up to 30 μg h−1 cm−2 of membrane area. BTEX removal efficiencies ranged from 75% to 99% depending on the BTEX concentration and vapor flowrate. Consequently, the system can be used for continuous removal and destruction of BTEX and other potential target VOCs in vapor phase streams. Journal of Industrial Microbiology & Biotechnology (2001) 26, 316–325.

This presentation is intended to commemorate the life’s work of a singular individual, Dr. Ralph C. Robbins, who was a pioneer among researchers studying the health benefits of flavonoids, particularly flavonoids such as hesperidin, tangeretin, nobiletin and others which occur in citrus fruits. Dr. Robbins entered the field in 1960, a time when research on health effects of flavonoids seemed to raise more questions than answers. To put Dr. Robbins’ research in perspective, let us first look very briefly at the history of flavonoid research.

This report describes studies on the degradation of nitroglycerin and nitroglycerin/perchlorate mixtures by an anaerobic mixed culture containing the perchlorate reducing bacterium HAP1. The final goal was to demonstrate the feasibility of biotreating a model hazard class 1.1 propellant (CYH) wastewater containing these compounds. The results showed that nitroglycerin rapidly disappeared under culture growth conditions. The disappearance appeared to be due to non-enzymatic chemical denitration resulting from the strong reducing potential generated in the medium. Nitroglycerin and nitrite were shown to inhibit perchlorate reduction. Both glycering and perchlorate were degraded in 10% CYH propellant wastewater. Perchlorate reduction in 25% and 50% CYH wastewater occurred only after nitroglycerin and nitrite were predegraded and the mixture culture was reinoculated. The other major components of the CYH wastewater, trice tin and resorcinol, were not inhibitory to perchlorate reduction.

Anaerobic degradation of the herbicide diuron, 3-(3,4-dichlorophenyl-1,1)dimethylurea, was studied. Enrichment cultures were established with seven different media in the presence of diuron (40 mg/liter). Media included combinations of sediment extract, mineral salts, and various organic amendments. Cultures were inoculated with aliquots of sediment collected from a pond previously treated with diuron and were maintained under an atmosphere of 95% N2 and 5% CO2. All enrichment cultures completely degraded diuron in 17–25 days. In all cultures showing diuron degradation, the product identified as 3-(3-chlorophenyl)-1,1-dimethylurea appeared in approximately stoichiometric amounts. Reinjection of diuron into each culture after 26 days resulted in rapid degradation of the parent herbicide with the appearance of proportionately more 3-(3-chlorophenyl)-1,1-dimethylurea. No other product was detected after 80 days in culture and the metachloro derivative was not degraded further during this time.

Visible and ultraviolet absorption and room temperature fluorescence excitation and emission spectra, obtained from alcoholic solutions of Florida orange juice (OJ) and orange pulpwash (PW), were used to characterize the collaborative study samples. The absorbance sum at 443, 325, and 280 nm and absorbance 443/325 nm ratio were used to estimate the percent total citrus material (TCM), OJ, PW, and dilution of the samples. Six laboratories participated in the study. Known samples of OJ and PW were given to each laboratory for familiarization and instrumental verification. Ten unknown samples (various combinations of OJ and PW) were analyzed by each laboratory. Three duplicate and 2 "closely matched pair" sample set combinations were reported. The results revealed that the method successfully detected the differences in sample formulations. The UV/vis and fluorescence spectrophotometric method has been adopted official first action for detecting adulteration of Florida orange juice with orange pulpwash.

Sterolic fractions ofRuppia maritima L.,Diplanthera wrightii Aschers,Halophila engelmanni Aschers,Syringodium filiforme Kutzing andThalassia testudinum Konig have been isolated. The sterolic fractions were characterized by IR spectroscopy and tentative identities of their components were determined by gas chromatography and mass spectrometry.

SUMMARY The flavor of orange juices was studied objectively through analyses of recovered volatile materials. Organic extracts of freshly recovered volatiles from juices of established varieties were shown with programmed-temperature gas chromatography (PTGC) and thermal conductivity detection to contain 40–50 components. Aroma profiles of the different juices were obtained with a programmed-temperature flame ionization gas chromatograph. Comparative evaluations were conducted of the flavor and aroma patterns of three varieties of Florida oranges: Hamlin, Pineapple, and Valencia. Preliminary investigation revealed no significant qualitative differences among varieties in gross analyses obtained with thermal conductivity an the ionization detection system using PTGC. Quantitative differences appeared responsible for the flavor differences noted among varieties. Analyses showed some compositional differences among varieties in control juices, peel-oil-free juices, their respective juice essences, and peel oils. The presence of certain chemical constituents in the juice was directly related to the peel oil. No significant qualitative differences existed in similarly prepared samples from different varieties. Some specific chemical identification and the methods used are outlined.

Steam-distilled leaf oils from 11 varieties of citrus were analysed and 28 compounds identified as constituents of one or more oils. Gas-liquid chromatographic (GLC) analyses were carried out on both analytical and semi-preparatory scales. Thin-layer chromatographic (TLC) data was obtained using both silica gel and aluminum oxide coated plates in conjunction with solvent systems of varying polarity. Mass spectral (MS) studies were conducted on a time-of-flight mass spectrometer.

Oils were extracted from the petals, stamens, and pistils of blossoms from two citrus species and from the petals and pistils of blossoms from a third by steam distillation. Analyses were performed using the techniques of gas-liquid chromatography, thin-layer chromatography, i.r. spectroscopy, and mass spectrometry. Thirty-eight compounds were isolated and identified.

The essential oils of “Valencia” orange peel and leaves were extracted at periodic intervals during the normal growing season, analyzed by gas-liquid chromatography, and qualitative variations noted. The major components of the peel oil from the very small immature fruit were linalool and sabinene, while at the end of the season (+)-limonene was the predominant compound in the mature fruit. The leaf oils did not show a pronounced seasonal variation. Analysis of the oils from petal, pistil, and stamen portions of the blossoms showed differences in their composition.

Five citrus methoxy flavones that have been found to have physiological activities on human erythrocyte can be separated and determined quantitatively by HPLC. Tangerine juice was found to have more nobiletin and tangeretin but lower amounts of the other three known flavones than orange juice. Several other peaks remain to be identified. Characteristic patterns of these juice flavones may be used to determine the presence of one juice in the other.

SUMMARY— Two approaches were used in a study of compounds contributing to the aroma of Hamlin oranges, which had been carefully handled to prevent release of peel‘oil. Volatile aromatic compounds emitted from the oranges on storage, and less volatile aroma compounds present on the cuticle of the fruit were isolated and analyzed. The volatile aroma of the stored oranges seemed to be contributed by ethyl esters, particularly ethyl butyrate, while sesquiterpene hydrocarbons appeared to be responsible for the persistent odor from the cuticle of fresh oranges. Volatile compounds definitely identified include ethyl acetate, ethanol, ethyl butyrate, limonene, ethyl caproate and ethyl caprylate. The sesquiterpene hydrocarbons on the cuticle consisted chiefly of valencene, with lesser amounts of elemene, caryophyllene, farnesene, humulene and cadinene.

Citrus fruit and leaf explants were fed linalool-3- 14 C. Volatile oils were recovered by steam distillation and fractionated by gas—liquid and thin-layer chromatography. α-Terpineol and other terpenoid alcohols were the predominant metabolites in leaves. Fruit also produced α-terpineol, but significant label could also be found in (+)-limonene and other hydrocarbons.

Sterolic fractions have been isolated from Recent marine sediments representing two different environments. The fractions were characterized by infrared spectroscopy and thin-layer chromatography. The major sterols in the fractions were identified by gas chromatography and mass spectrometry. The demonstrated survival of these common plant and animal sterols for several thousand years suggests that these molecules will be useful geochemical indicators.

The ability of 18 gram-negative bacterial isolates to detoxify diisopropyl fluorophosphate, a structural analog of the agents soman and sarin, was investigated. Detoxification by both frozen cell sonicates and acetone powders was assayed by two methods, i.e., the hydrolytic release of fluoride, measured by a fluoride-specific ion electrode, and the disappearance of acetylcholinesterase inhibition in vitro. Frozen cell sonicates for all strains exhibited some activity (F- ion release). In general, acetone powder preparations produced higher activity than frozen cell sonicates did, and the highest activities were exhibited by strains with known parathion hydrolase activity. Two ranges in activity were observed, low level, ranging from 0.1 to 7.0 mumol/min per g of protein, and high level, detected only in parathion hydrolase-producing strains, from 47 to greater than 300 mumol/min per g of protein. Results indicate that parathion hydrolase was nonspecific in phosphoesterase activity. Also, it was an effective detoxicant at low concentrations and near-neutral pH.