Improving Nutritive Value of Purple Field Corn Residue and Rice Straw by Culturing with White-Rot Fungi

Abstract

It was hypothesized that white-rot fungus fermented with rice straw and purple field corn improves nutrient utilization via enhanced digestibility and lowers methane (CH4) production due to the effects of the lovastatin compound. The aim of the current experiment was to investigate the effect of inoculation of two fungi belonging to white-rot fungus type on feed value and ruminal fermentation characteristic. The experiment was carried out according to a completely randomized 3 × 3 factorial design: three roughage sources (rice straw, purple corn stover, and purple corn field cob) for three inoculation methods (untreated, P. ostreatus treated, and V. volvacea treated). The two fungi increased concentration of lovastatin when compared to the untreated, and P. ostreatus had higher lovastatin production potential than V. volvacea (p < 0.05). The yield of lovastatin was obtained from rice straw fermentation with P. ostreatus. The monomeric anthocyanin content (MAC) in untreated purple field corn cobs was higher than in the fermentation groups. Ruminal fermentation gas production from soluble fractions ranged from −2.47 to 1.14 and differed among the treatments (p < 0.01). In comparison to all treatments, the gas production rate for the insoluble fraction was significantly highest (p < 0.01) in treatment alone, in which purple field corn stover was fermented with P. ostreatus and V. volvacea. There was significant interaction in in vitro dry matter digestibility at 12 h of incubation. Purple field corn cob had a higher significant effect on in vitro DM digestibility at 12 and 24 h after incubation when compared to that of other groups. Moreover, current research has found that roughage fermented with P. ostreatus and V. volvacea increased in vitro DM digestibility at 24 h after incubation. Fermenting roughage with fungi did not affect rumen pH, which ranged from 6.60 to 6.91 (p > 0.05), while P. ostreatus resulted in increased levels of ruminal ammonia-nitrogen concentrations. Propionic acid increased in all roughages fermented with P. ostreatus or V. volvacea after 8 h of ruminal fermentation testing. The two fungi fermented as substrate treatments had significantly lower (p < 0.05) CH4 production. Based on the improved rumen DM digestibility and reduced CH4 production, P. ostreatus and V. volvacea could be utilized for enhancing feeding efficiency of roughage.

Pleurotus Ostreatus and Volvariella Volvacea Can Enhance the Quality of Purple Field Corn Stover and Modulate Ruminal Fermentation and Feed Utilization in Tropical Beef Cattle

“…Methyl coenzyme-M reductase (mcr) is the key enzyme in the methanogenesis process [5,41]. These results were supported by our previous in vitro test, which showed that fermenting roughage with P. ostreatus and V. volvacea significantly reduced CH 4 production by approximately 10.83% to 11.32% compared to the untreated substrates [12]. Likewise, Jahromi [14] reported that lovastatin in fermented rice straw is effective at suppressing 96.43% of the CH 4 emission.…”

“…Hristov et al [42] demonstrated that protein could degrade into NH 3 -N by microbial extracellular enzymes and deamination. Likewise, a previous report indicated that NH 3 -N was increased by roughage fermented with white rot as compared with a control in vitro [12]. Moreover, the high NH 3 -N concentration in the roughage fermented with P. ostreatus was probably influenced by the high CP level, which is a supplemental source of N. In addition, P. ostreatus and V. volvacea are composed of CP, and there is a probability of additional protein supply to the cattle.…”

“…To realize MAC stability during roughage-treated storage, the relationship between MAC stability and lactic fermentation should be explained, because MAC contains anthocyanidin and sugars, and there is a possibility that sugars from MAC are used as a substrate for lactic fermentation [28,29]. The lovastatin concentration was 32.49 to 33.96 g/kg DM when roughages were fermented with P. ostreatus and V. volvacea, closely studied by Khonkhaeng [12]. Lovastatin can be produced by P. ostreatus and V. volvacea by controlling the culture conditions.…”

“…The lovastatin has been demonstrated to effectively inhibit the HMG-CoA reductase enzyme in methanogenic bacteria by interfering with the assembly of isoprenoid chains needed for membrane phospholipid synthesis and thus selectively depressing the growth of methanogenic bacteria without affecting other ruminal microorganism community [12][13][14]. Our previous work found that purple field corn stover fermented with P. ostreatus and V. volvacea can be beneficial when fed as an alternative fiber feed to improve in vitro digestibility, rumen fermentation, and reduction of CH 4 production [12]. However, there is a lack of information on whether purple field corn fermented with P. ostreatus and V. volvacea is effective in beef cattle.…”

Technical and economic feasibility of an integrated ethanol and anthocyanin coproduction process using purple corn stover

“…presenting a conservative case with respect to bioethanol production. Purple corn stover hybrids with higher structural carbohydrate content have been reported 26,27 . Thus, the effect of low (LSC) and high structural carbohydrate content (HSC) on MESP of the modified processes was evaluated (Table 7).…”