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M Parish

Publications and source records attributed to M Parish.

6 recordsLinked to original sources
PubMed2005

Identification of medicinal off-flavours generated by Alicyclobacillus species in orange juice using GC-olfactometry and GC-MS.

AIMS: The objective of this study was to identify compounds responsible for medicinal off-flavours produced by different species and strains of Alicyclobacillus in orange juice using a combination of chromatographic-coupled olfactometric techniques and gas chromatography-mass spectrometry (GC-MS). METHODS AND RESULTS: Each of five Alicyclobacillus strains was inoculated into separate juice samples and incubated up to 28 days at 45 degrees C. Aroma compounds in the juice were analysed by GC-olfactometry (GC-O) and confirmed using GC-MS. GC-O identified three components that were described as medicinal/antiseptic. Microbial populations were enumerated at timed intervals by spiral plating onto Alicyclobacillus agar. Within 28 days incubation, all five strains produced medicinal off-aromas from guaiacol and at least one halogenated phenol. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to evaluate individual juice aroma components produced by Alicyclobacillus species using olfactometry and to demonstrate that at least three medicinal off-flavour compounds are associated with the growth of alicyclobacilli in orange juice.

Beverages↗
PubMed1995

NGF modulates sympathetic innervation of lymphoid tissues.

Immune tissues are known to be innervated by the sympathetic nervous system, but little is known of what directs the innervation to specific tissue compartments. This report examines the sympathetic innervation of immune tissues in transgenic mice that overexpress nerve growth factor (NGF) in skin and other epithelial structures. NGF transgenic mice exhibited dramatic hyperinnervation in the splenic marginal zone, and the medulla and capsule of peripheral lymph nodes. In contrast, the transgenic mesenteric lymph nodes showed no hyperinnervation. This difference correlated with the location of these nodes; peripheral lymph nodes drain skin where the transgene was expressed while mesenteric lymph nodes drain non-transgene-expressing structures. In addition, the level of innervation correlated with the level of NGF peptide content as assayed by ELISA (3- and 13-fold increase in transgenic spleen and axillary lymph nodes, respectively; no increase in mesenteric nodes) and immunocytochemistry. RT-PCR showed that the NGF transgene was not being expressed in the immune tissues, suggesting that immune tissues can concentrate transgene-produced NGF. It was also demonstrated that the change in innervation had functional consequences. The mitogen response to concanavalin A (ConA) by spleen cells was decreased in the transgenics suggesting that elevated catecholamines or NGF can modulate the proliferative response of these cells. These mice demonstrate that NGF can modulate the sympathetic innervation and function of the immune system.

Animals↗