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Wildfires have become increasingly common across the United States in recent decades, with significant implications for ecosystem health and sustainability. The viability and metabolic activity of soil bacteria are key for maintaining global nitrogen-cycling processes and are likely to be impacted as burn severity continues to increase. To this end, wildfire-affected soils were studied to examine the impact on nitrogen-cycling bacteria in soils affected by low, moderate, and high wildfire severities. This objective was achieved by characterizing soil bacterial communities in control (i.e., unburned) and burned soils collected one year following the Woolsey wildfire (Los Angeles and Ventura Counties, CA, USA) using Illumina MiSeq 16S sequencing and profiling nitrogen-cycling gene expression using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Six families and 17 genera were significantly (Spearman rs > |0.4|; p < 0.05) negatively associated with wildfire severity, and three families and six genera were significantly positively associated with wildfire severity. Many of these taxa contain species that are known to be critical contributors to maintaining global nitrogen cycles. NosZ and NirS nitrifying genes had significantly lower transcription rates in high-severity samples compared with control and low/moderate-severity samples. Collectively, these results suggest that high-severity wildfires significantly negatively alter the community structures and functions of nitrogen-cycling bacteria, which may have significant ramifications for ecosystem recovery in postwildfire landscapes. [ABSTRACT FROM AUTHOR]

Byline: E. Gomez-Plaza (1), Rocio Gil-Munoz (1), J. Carreno-Espin (1), Jose Antonio Fernandez-Lopez (2), Adrian Martinez-Cutillas (1) Keywords: Key wordsaWine; Grape; Aroma; Volatile compounds; Clones Abstract: aAnalysis of the volatile compounds of wines from seven clones of Monastrell grapes was performed using ultrasound extraction of the compounds. Significant differences were found for some of the compounds and these compounds were used in order to characterize and differentiate among the clones. Linear discriminant analysis allowed some grouping of the clones, showing that differentiation among clones of a neutral grape variety is possible. Author Affiliation: (1) Centro de Investigacion y Desarrollo Agroalimentario, Consejeria de Medio Ambiente, Agricultura y Agua, Ctra. La Alberca s/n, E-30150 La Alberca, Murcia, Spain e-mail: Encarna.Gomez @accesosis.es, ES (2) Departamento de Ingenieria Quimica, Escuela Superior de Ingenieros Agronomos, Universidad de Murcia, Paseo Alfonso XIII, Cartagena, Murcia, Spain, ES Article note: Received: 21 April 1998 / Revised version: 19 November 1998

Objective: The aim of the present study is to investigate the effect of antioxidant polyphenol-rich pomegranate juice (PJ) supplementation for 5 weeks on patients with stable chronic obstructive pulmonary disease (COPD), since the oxidative stress plays a major role in the evolution and pathophysiology of COPD. Design: A randomized, double-blind, placebo-controlled trial was conducted. Subjects: A total of 30 patients with stable COPD were randomly distributed in two groups (15 patients each). Interventions: Both groups consumed either 400 ml PJ daily or matched placebo (synthetic orange-flavoured drink) for 5 weeks. Trolox Equivalent Antioxidant Capacity (TEAC) of PJ, blood parameters (14 haematological and 18 serobiochemical), respiratory function variables, bioavailability of PJ polyphenols (plasma and urine) and urinary isoprostane (8-iso-PGF[sub.2[alpha] ]) were evaluated. Results: The daily dose of PJ (containing 2.66 g polyphenols) provided 4 mmol/l TEAC. None of the polyphenols present in PJ were detected in plasma or in urine of volunteers. The most abundant PJ polyphenols, ellagitannins, were metabolized by the colonic microflora of COPD patients to yield two major metabolites in both plasma and urine (dibenzopyranone derivatives) with no TEAC. No differences were found (P [greater than] 0.05) between PJ and placebo groups for any of the parameters evaluated (serobiochemical and haematological), urinary 8-iso-PGF[sub.2[alpha] ], respiratory function variables and clinical symptoms of COPD patients. Conclusions: Our results suggest that PJ supplementation adds no benefit to the current standard therapy in patients with stable COPD. The high TEAC of PJ cannot be extrapolated in vivo probably due to the metabolism of its polyphenols by the colonic microflora. The understanding of the different bioavailability of dietary polyphenols is critical before claiming any antioxidant-related health benefit. Sponsorship: &apos;Fundaci#243;n S#233;neca&apos; (Murcia, Spain), Project PB/18/FS/02 and Spanish CICYT, Project AGL2003-02195. European Journal of Clinical Nutrition (2006) 60, 245-253. doi: 10.1038/sj.ejcn.1602309; published online 9 November 2005 Keywords: antioxidant, ellagitannin, ellagic acid, oxidative stress, bioavailability, microflora, Author(s): B Cerda [1]; C Soto [2]; M D Albaladejo [3]; P Martinez [3]; F Sanchez-Gascon [2]; F Tomas-Barberan [1]; J C Espin [1] Introduction The 2002 WHO World Health [...]