Synergy of 1-MCP and hypobaric treatments prevent fermented flavour and improve consumers' acceptability of 'Shughri' pear.

Development of fermented flavour during storage reduces acceptability of Shughri pear. Therefore, the current study was designed to investigate the combined effect of 1-Methylcyclopropene (1-MCP) and hypobaric treatment on stability of Shughri pear during 120 days of storage. Fruit were treated individually or combinedly with 25, 50, and 75 kilo pascal hypobaric treatments for 4 h and 1-MCP (0.3 µLL-1 and 0.6 µLL-1) for 24 h, whereas control received no treatment. The pears were stored for 120 days at (0 ± 1 °C, 85 ± 5% RH), and were evaluated after every 30 days. After cold storage, pears were shifted to simulated retail conditions (20 ± 3 °C, 65 ± 5% RH). The combination of 25 kPa + 0.6 µLL-1 1-MCP significantly (P ≤ 0.05) delayed fruit ripening, reduced Alcohol dehydrogenase (ADH), and Pyruvate decarboxylase (PDC) activities, maintained the quality, and led to higher consumers' acceptability of the pear followed by 50 kPa + 0.6 µLL-1 and 25 kPa + 0.3 µLL-1. The control fruit were marketable for a week after storage with relatively less acceptability due to fermented flavour compared to treated fruit, marketable for more than two weeks. Among all the treatments, the synergy of 1-MCP and hypobaric treatment 25 kPa + 0.6 µLL-1 1-MCP improved the postharvest storage life and quality parameters, preventing development of fermented flavour in the pears. The experiment was conducted on pilot scale, for commercial application, the results of this study should be validated on large scale.

Hypobaric treatment augments the efficacy of 1-MCP in apple fruit.

This research aimed to extend the postharvest shelf life of Royal Gala apple during cold storage and maintain its market value in simulated retail conditions. Apples were treated with hypobaric pressure (50 kPa for 4 h) followed by 1-MCP (0.5 µL L-1, 0.7 µL L-1, and 1.0 µL L-1) treatment for 24 h individually and in combinations, stored at (1 ± 1 °C, 85 ± 3% RH) for 120 d and analyzed for different quality parameters (Peel color, firmness, weight loss, TSS, acidity, ethylene production rate, and respiration rate) at each 30 d interval, followed by a 20 d simulated retail condition at 20 ± 3 °C with 4 d interval. Results indicated that all 1-MCP concentrations were more effective in retaining quality compared to individual hypobaric treatment. However, a synergistic effect was observed by combining 1-MCP with hypobaric treatment. Among the combined treatments, 1.0 µL L-11-MCP + 50 kPa more effectively and significantly retained quality during cold storage. Furthermore, the apples were more juicy, tasty, and attractive in color than others in simulated conditions. Addition of hypobaric treatment to 1-MCP might reduce endogenous ethylene in fruit by outward diffusion and blocking further ethylene synthesis by the action of 1-MCP. However, in-depth study is required for further understanding the phenomena.

Chemical composition, ruminal degradation kinetics, and methane production (in vitro) of winter grass species.

BACKGROUND: Information about the nutritive value, dry matter (DM) digestibility, and methane (CH4 ) emission potential of grass species is required for their optimal utilization in ruminant rations. The present study was designed: (i) to quantify the nutrient profile, mineral composition and in vitro dry matter digestibility (IVDMD) of winter grass species commonly available in northern Pakistan; and (ii) to measure the in vitro gas production (IVGP) and CH4 emission of the grass species during 72 h in vitro ruminal fermentation. Seven grass species, namely, Cenchrus ciliaris, Setaria anceps, Panicum antidotale, P. maximum, Pennisetum purpureum, Pennisetum orientale, and Atriplex lentiformis were assessed. RESULTS: A high level of variability (P < 0.001) was observed among grass species for the content of all measured nutrients, IVDMD, IVGP, and CH4 -production. Notably, the content (g kg-1 DM) of crude protein varied from 59.8 to 143.3, neutral detergent fiber from 560.3 to 717.9, IVDMD from 375.1 to 576.2, and 72 h cumulative IVGP from 97.6 to 227.4 mL g-1 organic matter (OM) and CH4 from 48 to 67 mL g-1 OM. Among the grasses, P. antidotale had greater content (g kg-1 DM) of crude protein (CP) (143.3), IVDMD (576.2), and 72 h cumulative IVGP (227.4 mL g-1 OM), and produced the smallest amount of total CH4 (48 mL g-1 OM) during 72 h fermentation. In contrast, A. lentiformis had the lowest content (g kg-1 DM) of CP (59.8), IVDMD (375.1), 72 h cumulative IVGP (97.6 mL g-1 OM), and produced a greater amount of total CH4 (67 mL g-1 OM) during 72 h fermentation. CONCLUSION: The findings of the current study highlight that it is possible to select and further develop grass species with high nutritional value and lower CH4 -production, which can improve livestock productivity, farm profitability, and long-term environment sustainability. © 2020 Society of Chemical Industry.

Identification of novel glycoside hydrolases via whole genome sequencing of Niabella ginsenosidivorans for production of various minor ginsenosides.

In this study, many bacterial strains were screened for the production of minor ginsenosides, but based on conversion competence among the strains, the strain Niabella ginsenosidivorans BS26T has the good ginsenoside-transforming ability. Therefore, the strain BS26T was selected for complete genome sequence analysis to determine the target (glycoside hydrolase) functional genes. Whole genome analysis of strain BS26T showed 43 glycoside hydrolase genes in total. To determine the target functional gene, 12 sets of six different glycoside hydrolases (3 set of ß-glucosidase; 3 set of trehalase; 3 set of arabinofuranosidase; 2 set of xylosidase; and one set of each α-galactosidase and α-fucosidase, respectively) were selected and cloned in E. coli BL21 (DE3) using the pGEX4T-1 vector and were characterized. Among these 12 sets of clones, only one, ß-glucosidase (BglNg-767), showed ginsenoside conversion ability. The BglNg-767 comprised 767 amino acids and belonged to glycoside hydrolase family 3 (GH3). The recombinant GST-BglNg-767 was capable of altering the ginsenosides Rb1, Rd, and gypenoside XVII (Gyp-XVII) to F2; Rb2 to C-O; Rb3 to C-Mx1, and Rc to C-Mc1. Besides, complete genome sequence analysis of strain BS26T also indicates 30 endopeptidase genes, which may be responsible for self-hydrolysis of the proteins. Therefore, using SDS-PAGE analysis, we predict that the difference between the molecular weight of the expressed protein (around 90 kDa) and the predicted amino-acid sequence (102.7 kDa) is due to self-hydrolysis of the proteins.