Non-volatile and volatile compound changes in blueberry juice inoculated with different lactic acid bacteria strains.

BACKGROUND: Lactic acid bacteria (LABs) are widely present in foods and affect the flavour of fermented cultures. This study investigates the effects of fermentation with Lactobacillus acidophilus JYLA-16 (La), Lactobacillus plantarum JYLP-375 (Lp), and Lactobacillus rhamnosus JYLR-005 (Lr) on the flavour profile of blueberry juice. RESULTS: This study showed that all LABs strains preferentially used glucose rather than fructose as the carbon source during fermentation. Lactic acid was the main fermentation product, reaching 7.76 g L-1 in La-fermented blueberry juice, 5.86 g L-1 in Lp-fermented blueberry juice, and 6.41 g L-1 in Lr-fermented blueberry juice. These strains extensively metabolized quinic acid, whereas oxalic acid metabolism was almost unaffected. Sixty-four volatile compounds were identified using gas chromatography-ion mobility spectrometry (GC-IMS). All fermented blueberry juices exhibited decreased aldehyde levels. Furthermore, fermentation with La was dominated by alcohols, Lp was dominated by esters, and Lr was dominated by ketones. Linear discriminant analysis of the electronic nose and principal component analysis of the GC-IMS data effectively differentiated between unfermented and fermented blueberry juices. CONCLUSION: This study informs LABs selection for producing desirable flavours in fermented blueberry juice and provides a theoretical framework for flavour detection. © 2023 Society of Chemical Industry.

Aroma profiles of sweet cherry juice fermented by different lactic acid bacteria determined through integrated analysis of electronic nose and gas chromatography-ion mobility spectrometry.

Sweet cherries are popular among consumers, with a recent explosion in sweet cherry production in China. However, the fragility of these fruits poses a challenge for expanding production and transport. With the aim of expanding the product categories of sweet cherries that can bypass these challenges, in this study, we prepared sweet cherry juice fermented by three different lactic acid bacteria (LAB; Lactobacillus acidophilus, Lactobacillus plantarum, and Lactobacillus rhamnosus GG), and evaluated the growth, physiochemical, and aroma characteristics. All three strains exhibited excellent growth potential in the sweet cherry juice; however, Lactobacillus acidophilus and Lactobacillus plantarum demonstrated more robust acid production capacity and higher microbial viability than Lactobacillus rhamnosus GG. Lactic acid was the primary fermentation product, and malic acid was significantly metabolized by LAB, indicating a transition in microbial metabolism from using carbohydrates to organic acids. The aroma profile was identified through integrated analysis of electronic nose (E-nose) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) data. A total of 50 volatile compounds characterized the aromatic profiles of the fermented juices by HS-GC-IMS. The flavor of sweet cherry juice changed after LAB fermentation and the fruity odor decreased overall. Lactobacillus acidophilus and Lactobacillus plantarum significantly increased 2-heptanone, ethyl acetate, and acetone contents, bringing about a creamy and rummy-like favor, whereas Lactobacillus rhamnosus GG significantly increased 2-heptanone, 3-hydroxybutan-2-one, and 2-pentanone contents, generating cheesy and buttery-like odors. Principal component analysis of GC-IMS data and linear discriminant analysis of E-nose results could effectively differentiate non-fermented sweet cherry juice and the sweet cherry juice separately inoculated with different LAB strains. Furthermore, there was a high correlation between the E-nose and GC-IMS results, providing a theoretical basis to identify different sweet cherry juice formulations and appropriate starter culture selection for fermentation. This study enables more extensive utilization of sweet cherry in the food industry and helps to improve the flavor of sweet cherry products.

Assessing influence for pharmaceutical data in zero-inflated generalized Poisson mixed models.

For clustered count data with excess zeros where the observations are either over-dispersed or under-dispersed, the zero-inflated generalized Poisson mixed (ZIGPM) regression model may be appropriate, in which the baseline discrete distribution is a generalized Poisson distribution, which is a natural extension of standard Poisson distribution. Motivated by one data set drawn from a pharmaceutical study, influence diagnostics for ZIGPM models based on case-deletion and local influence analysis are developed in this work. The one-step approximations of the estimates under case-deletion model and some case-deletion measures are given. Meanwhile, local influence measures are obtained under various perturbations of the observed data or model assumptions. Results from a pharmaceutical study illustrate the usefulness of the diagnostic statistics.

The expressions of HSP 70 mRNA and c-fos mRNA in the skeletal muscle and cardiac muscle of rabbits by electrocuted / 法医学杂志

OBJECTIVE@#To study the changes of HSP 70 mRNA and c-fos mRNA expression and to find a method to differentiate antemortem from postmortem electrocution.@*METHODS@#Fifteen New Zealand rabbits were randomly divided into three groups, the antemortem electrocution group, the postmortem electrocution group, and the control group. Each group consists of five rabbits. The levels of HSP 70 mRNA and c-fos mRNA in skeletal muscle and cardiac muscle were examined with quantitative fluorescent RT-PCR.@*RESULTS@#The levels of HSP 70 mRNA and c-fos mRNA in the antemortem electrocution group increased significantly (P<0.05), compared with that of the postmortem electrocution group.@*CONCLUSION@#The changes of HSP 70 mRNA and c-fos mRNA expression in skeletal muscle and cardiac muscle can be used as an indicator to distinguish antemortem from postmortem electrocution.

Study on preventing effects of procyanidins on selenite cataract development in rats / 中国中药杂志

<p><b>OBJECTIVE</b>To study the preventing effects of procyanidins (PC) on selenite cataract in rats and the time-effect relationship.</p><p><b>METHOD</b>Forty five SD rats were divided into three groups: control, model and experiment groups. The rats in the experiment group were fed additionally with the PC by 80 mg x kg(-1) when they were supplied the equal selenite with the model group. Five rats of each group were regularly sacrificed by bleeding from femoral artery at sixth, eleventh, sixteenth day and the level of malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) of all lenses was measured.</p><p><b>RESULT</b>Compared with the model group, the level of the MDA in the experiment group at the eleventh day and the sixteenth day greatly decreased (P < 0.01). At the sixteenth day the level of the SOD and GSH-Px had an increase (P < 0.01), which showed its anti-oxygenation.</p><p><b>CONCLUSION</b>PC indicated the obvious inhibition in the development of the rat cataract. The treatment period was recommended at least for fifteen days.</p>

Effects of Perinatal Bisphenol A Exposure on the Development of Brain of the F1 Generation Male SD Rats / 环境与健康杂志

Objective To investigate the effect of perinatal bisphenol A BPA exposure on brain development of F1 male offspring. Methods Pregnant SD rats were given BPA at 2 20 and 100 mg/kg body weight per day respectively from eleventh day of gestation to the whole lactation by gavage until their pups were weaned on postnatal day 21  the control group had no BPA exposure. Every six F1 male pups from each of the four groups were killed at differential time points on postnatal day 1510152130 and 45 respectively. Histopathological examination by HE stain was done on the brains. Results The results showed no abnormal change was found on postnatal day 1-10. Three dosage groups showed abnormal change of different degree on 15th 21th 30th postnatal day the mainly abnormal change was karyopyknosis of pyramidal cell in CA3 of hippocampus and cortical neuron in cerebral cortex. The cell numbers of pyramidal cell in CA3 of hippocampus and cerebral cortex were decreased on 45th postnatal day. Conclusion Perinatal BPA exposure may have an adverse effect on the brain developmnent of F1 male offspring.