Laticifers are highly specialized cells that synthesize and store natural rubber. Rubber trees (Hevea brasiliensisMuell. Arg.) contain both primary and secondary laticifers. Morphological and functional differences between the two types of laticifers are largely unknown, but such information is important for breeding and cultivation practices. Morphological comparison using paraffin sections revealed only distribution differences: the primary laticifers were distributed randomly, while the secondary laticifers were distributed in concentric rings. Using isolated laticifer networks, the primary laticifers were shown to develop via intrusive “budding” and formed necklace-like morphology, while the secondary laticifers developed straight and smooth cell walls. Comparative transcriptome analysis indicated that genes involved in cell wall modification, such as pectin esterase, lignin metabolic enzymes, and expansins, were highly up-regulated in the primary laticifers and correspond to its necklace-like morphology. Genes involved in defense against biotic stresses and rubber biosynthesis were highly up-regulated in the primary laticifers, whereas genes involved in abiotic stresses and dormancy were up-regulated in the secondary laticifers, suggesting that the primary laticifers are more adequately prepared to defend against biotic stresses, while the secondary laticifers are more adequately prepared to defend against abiotic stresses. Therefore, the two types of laticifers are morphologically and functionally distinct.

The objective of this work was to explore the relationship between the microbial communities of sourdoughs collected from the Xinjiang and Gansu areas of China and the quality of steamed bread. Compared to yeast-based steamed bread, sourdough-based steamed bread is superior in terms of its hardness, adhesiveness, flexibility, and chewiness. It is rich in flavor compounds, but a significant difference in volatile flavor substances was observed between the two sourdoughs. A total of 19 strains of lactic acid bacteria (LAB) were isolated from the Gansu sourdough sample, in which Lactiplantibacillus plantarum and Pediococcus pentosaceus were the dominant species, accounting for 42.11% and 36.84%, respectively. A total of 16 strains of LAB were isolated from the Xinjiang sourdough sample, in which Lactiplantibacillus plantarum was the dominant species, accounting for 75%. High-throughput sequencing further confirmed these results. Clearly, the species diversity of Gansu sourdough was higher. The volatile profiles of the sourdoughs were similar, but differences in the individual volatile compounds were detected between the sourdoughs of the Gansu and Xinjiang regions. These results point out that the differences in the microbiota and the dominant strains lead to differences in the quality of sourdoughs from region to region. This investigation offers promising guidance on improving the quality of traditional steamed bread by adjusting the microorganisms in sourdough.

The objective of this work was to explore the ability of lactic acid bacteria strains to bind benzo(a)pyrene (B(a)P) existing in PM_2.5. In this study, we examined the ability of Lactobacillus acidophilus NCFM to bind B(a)P in the simulated PM_2.5 environment. Among the tested 5 strains, Lactobacillus acidophilus NCFM exhibited the best capacity to bind B(a)P, and its B(a)P binding percentage was 60.00. Simulations of organic and inorganic systems which represent PM_2.5 indicated that B(a)P could be absorbed by strain L. acidophilus NCFM. For the inorganic system of pH 5, L. acidophilus NCFM bound 92.74 B(a)P with a cell concentration of 1×10¹⁰cfu/mL at 37°C for 8hr. Regarding the organic system with pH 6, 73.00 B(a)P was bound by strain L. acidophilus NCFM after this bacterium was incubated at 37°C for 10min. A quick B(a)P binding by this probiotic bacterium took place in the organic system. The removal of B(a)P from PM_2.5 was significantly related to incubation time, cultivation temperature, pH, and cell concentration. Thus, our finding shows that long-term consumption of L. acidophilus NCFM is beneficial for the reduction of B(a)P towards the population who are exposed to PM_2.5, although the ability of this bacterium to adsorb B(a)P is partly affected by the differences in the origin of PM_2.5.

Schisandra is a plant whose fruit possesses high biological potential and beneficial health effects. The pharmacological properties of Schisandra are attributed to its bioactive components, primarily polyphenols and polysaccharides. This study aimed to obtain Schisandra fruit extracts (SCE) from different locations in China and Poland, as well as Schisandra polysaccharides (SPO), and to compare their chemical composition and selected biological activities. The prebiotic and antibacterial effects of SCE and SPO on lactic acid bacteria (LAB), human and foodborne pathogens, and gut microbiota were investigated. The chemical composition of the three Chinese SCE was similar, whereas SCE from Poland (SCE-PL) differed. The main bioactive compounds differentiating the Chinese SCE were quercetin, isorhamnetin, and nicotiflorin, while gamma-tocopherol and mevalonic acid distinguished SCE-PL, as indicated through LC-QTOF-MS/MS metabolomic profiling. All SCE and SPO promoted the growth of LAB strains, confirming their prebiotic potential and ability to serve as effective carbon sources for LAB. Additionally, all SCE inhibited the growth of certain pathogens, with S. chinensis extract from China showing the strongest activity, whereas SPO did not exhibit such activity. Variations in chemical composition among SCE and SPO contribute to differences in their prebiotic and antimicrobial activity, highlighting the importance of species and geographical origin in determining their functional properties.