ABSTRACT
[This corrects the article DOI: 10.3389/fmicb.2022.1090401.].
ABSTRACT
Tibetan Plateau is facing serious shortage of forage in winter and spring season due to its special geographical location. Utilization of forages is useful to alleviate the forage shortage in winter and spring season. Consequently, the current study was aimed to evaluate the influence of storage time on the silage quality and microbial community of the maize (Zea mays L.) and faba bean (Vicia faba L.) mixed silage at Qinghai-Tibet Plateau. Maize and faba bean were ensiled with a fresh weight ratio of 7:3, followed by 30, 60, 90, and 120 days of ensiling. The results showed the pH value of mixed silage was below 4.2 at all fermentation days. The LA (lactic acid) content slightly fluctuated with the extension of fermentation time, with 33.76 g/kg DM at 90 days of ensiling. The AA (acetic acid) and NH3-N/TN (ammonium nitrogen/total nitrogen) contents increased with the extension of fermentation time and no significantly different between 90 and 120 days. The CP (crude protein) and WSC (water soluble carbohydrate) contents of mixed silage decreased significantly (P < 0.05) with ensiling time, but the WSC content remained stable at 90 days. The Proteobacteria was the predominant phyla in fresh maize and faba bean, and Pseudomonas and Sphingomonas were the predominant genera. After ensiling, Lactobacillus was the prevalent genus at all ensiling days. The relative abundance of Lactococcus increased rapidly at 90 days of ensiling until 120 days of fermentation. Overall, the storage time significant influenced the silage fermentation quality, nutrient content, and microbial environment, and it remained stable for 90 days of ensiling at Qinghai-Tibet Plateau. Therefore, the recommended storage time of forage is 90 days in Qinghai-Tibet Plateau and other cool areas.
ABSTRACT
This study assessed the fermentation quality and microbial community of corn (Zea mays L.) and soybean (Glycine max Merr.) (CS) mixed silage in strip intercropping system. CS mixed silage increased lactic acid content and decreased ammonia-N content compared to 100% soybean (S) silage, while it decreased ammonia-N content compared to 100% corn (C) silage. The largest number of epiphytic lactic acid bacteria was detected in CS fresh materials. During ensiling, Weissella and Lactobacillus dominated silage, the relative abundance of Lactobacillus in mixed silage was higher than that in S silage with the same S variety. After aerobic exposure (AE), synergistic effect existed in low relative abundance bacteria correlating with ammonia-N content and pH at ensiling 60 days and AE 7 days. In conclusion, CS mixed silage modified microbial community and improved fermentation quality.
Subject(s)
Silage , Zea mays , Fermentation , Lactobacillus , Glycine maxABSTRACT
OBJECTIVE: To optimize the ultrasonic extraction condition for oleanolic acid from Akebia trifoliata. METHOD: According to the orthogonal design L9 (3(4)), the optimum ultrasonic extraction technique was sought through experimental investigation, and was compared with the routine extraction technics. The contents of oleanclic acid were determined by UV-spectrophotometry. RESULT: The order of factors to affect the oleanolic acid extraction was extraction time > ethanol concentration > ultrasonic power > ration of interval time to ultrasonic time. The optimum ultrasonic extractions were A2B3C1D2. CONCLUSION: Compared with traditional extraction, ultrasonic method can save time, be easy to operate, improve extraction rates and need no heating.
