Volatile flavour components, microbiota and their correlations in different sufu, a Chinese fermented soybean food

AIM

To investigate the volatile flavour components (VFCs), microbiota and their correlations of three categories of sufu, a Chinese fermented soybean food.

METHODS AND RESULTS

The VFCs were analyzed by headspace solid-phase micro-extraction (HS-SPME) combined with gas chromatography and mass spectrometry. A total of 141 VFCs were tentatively identified, in which 12 esters, eight aldehydes, five alcohols and nine miscellaneous compounds were recognized as the characteristic VFCs through the relative odour activity value. The complex microbial community was revealed by Illumina MiSeq sequencing. Among the total 202 bacteria and 125 fungi species identified, 16 bacteria and 7 fungi species were revealed as dominant community members. Furthermore, the VFC-microbiota correlation was characterized by Spearman's rank correlation coefficients (ρ). Based on the positive VFC-microbiota correlation, two bacterial species and three fungal species were selected as potential flavour-producing microbiota.

CONCLUSIONS

A variety of VFCs and complicated microbiota were observed in the three categories of sufu. Lactococcus lactis, Sphingobacterium sp., Pichia fermentans, Kodamaea ohmeri and Saccharomyces rouxii were the potential flavour-producing microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

The preliminary results would be useful for designing starter cultures to produce sufu with desirable sensory properties, consistent flavour and shorter ripening time. Furthermore, these results will also provide a new insight to improve the flavour quality of traditional fermented soybean food.

Depth of field extension and objective space depth measurement based on wavefront imaging

When all the parts of the wavefront imaging system are kept static after wavefront measuring, the target's images are blurry, because the depth of field (DOF) of the system affects the imaging quality. In this paper, the method for extending the DOF of the wavefront imaging system through an integrated architecture of a liquid-crystal microlens array (LCMLA) powered by electricity and a common photosensitive array, is presented. The DOF can be extended remarkably only by stitching together several sub-images of the LCMLA. The problem that the wavefronts and imaging results are insensitive to the objective depth is also solved. Optimal driving voltage signals are found out according to Sobel mean gradient to efficiently calibrate the depth of objective space in order to quantitatively measure the depth. The approach indicates a viable way to effectively extend the DOF of imaging micro-systems and to measure the geometrical depth of targets at the same time.

Knowledge regarding hepatitis B mother-to-child transmission among healthcare workers in South China

To determine the knowledge regarding hepatitis B virus (HBV) mother-to-child transmission (MTCT) and its prevention and treatment among healthcare workers (HCWs) in Guangdong Province, China, an HBV endemic area. An HBV knowledge questionnaire was administered to 900 HCWs from the 3rd Affiliated Hospital of Sun Yat-Sen University and 2 rural hospitals in Guangdong Province. The 27 items in the questionnaire fell into 3 sections: HBV MTCT general knowledge, respondents' practices of preventing HBV MTCT and awareness of the resources of preventing HBV MTCT. The data collected were coded and analysed using SPSS software version 20. In total, 503 of 900 HCWs responded to the survey (response rate: 55.9%). Eighty-four individuals responded correctly to all of the knowledge questions: 58 were doctors, and 26 were nurses (P < .05). Doctors more often performed practices than nurses (t = 3.591, P < .01). Participants from the infectious disease department demonstrated a significantly higher proportion of correct answers and resource utilization than other specialties (χ²  = 14.052, 7.998, P < .01). In terms of the average knowledge score, t test or ANOVA showed that there were significant differences between the specialty groups (t = 3.110, P < .01), hospital level groups (t = 2.337, P < .05) and age groups (F = 3.020, P < .05). Respondents' initiative increased with hospital level and age (t = 2.993, 7.493, P < .01). A considerable percentage of HCWs has misconceptions about HBV MTCT. Healthcare workers, in particular nurses, those working in noninfectious disease departments or township hospitals and younger medical staff, lack systematic and comprehensive knowledge about HBV MTCT and are in urgent need of HBV-related training.

[Study on the current status of smoking, intention of tobacco concession and related risk factors among 18-65-year olds patients with chronic diseases in Beijing]

Objective: To understand the status, attitude and related risk factors on smoking among 18-65 years old patients with hypertension, diabetes, dyslipidemia, chronic obstructive pulmonary disease (COPD) or asthma in Beijing. Methods: Data was gathered from the 2014 Beijing Non-communicable and Chronic Disease Surveillance Program. Multiple classified cluster sampling method was used and 19 815 participants aged 18-65 were sampled from 16 districts in Beijing. Results: Among all the 18 405 participants, male hypertensive patients showed a higher rate on current smoking than the other groups (χ(2)=17.695, P<0.001). Male patients with dyslipidemia had higher current smoking rate than the other groups (χ(2)=39.292, P<0.001). However, female patients with COPD or with asthma showed higher rate on current smoking than the other groups (χ(2)=6.276, P=0.012), (χ(2)=8.245, P=0.004). Among the smokers, hypertensive patients presented lower rate (χ(2)=20.487, P<0.001) on intention of smoking concession, than the other groups. Patients with COPD showed greater intention in quitting smoking (χ(2)=6.085, P=0.048), than the other groups. Male patients with diabetes (χ(2)=9.219, P=0.010) or dyslipidemia (χ(2)=13.513, P=0.001) who had stopped smoking tobacco appeared having higher rates in keeping the current status. Results from logistic regression analyses showed that smoking was the risk factor for hypertension (OR=1.17), dyslipidemia (OR=1.25), COPD (OR=1.78), and asthma (OR=1.57). Conclusions: Patients with certain kinds of chronic diseases showed higher rate of current smoking and lower rate of quitting. Cigarette consumption appeared an important risk factor for patients with hypertension, dyslipidemia, COPD, or asthma in Beijing.