Adult (ADS) and larva stages of palm weevil Rhynchophorus phoenicis were analyzed for their nutritional potentials using proximate and mineral contents as indices. The early larva stage (ELS) contains the highest mois...Adult (ADS) and larva stages of palm weevil Rhynchophorus phoenicis were analyzed for their nutritional potentials using proximate and mineral contents as indices. The early larva stage (ELS) contains the highest moisture content of 11.94% while ADS has the least value of 4.79%. The late larva stage (LLS) has the highest protein content of 10.51% while ADS contains 8.43%. Ash content is highest in ELS with a value of 2.37% and lowest in ADS with a value of 1.43%. ELS and LLS have the highest (22.14%) and lowest (17.22%) fibre contents respectively. The values of potassium, magnesium and iron in ELS were (455.00±21.21), (60.69±2.57) and (6.50±3.40) mg/kg while LLS recorded (457.50±10.61), (43.52±1.37) and (6.00±1.10) mg/kg and ADS recorded (372.50±24.75), (53.31±1.88) and (22.90±3.70) mg/kg. Chromium, phosphorus, nickel, calcium, lead, man- ganese and zinc were also detected. Copper was not detected in any of the samples. In all the developmental stages the protein solubilities were pH dependent with the minimum protein solubilities occurring at acidic pH while the maximum protein solu- bilities occurred at alkaline pH.展开更多
Acid mine drainage(AMD)has become a widespread environmental issue and its toxicity can cause permanent damage to the ecosystem.However,there are few studies focusing on the formation of AMD under moderately thermophi...Acid mine drainage(AMD)has become a widespread environmental issue and its toxicity can cause permanent damage to the ecosystem.However,there are few studies focusing on the formation of AMD under moderately thermophilic conditions,hence we employed X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and 16S rRNA sequencing to study the dissolution of pyrite and bornite by a moderate thermophilic consortium,and explored the role of free and attached microorganisms in the formation of AMD.The consortium mainly comprised Acidithiobacillus caldus,Leptospirillum ferriphilum and Sulfobacillus thermosulfidooxidans.The results indicated that total iron in pyrite solution system reached 33.45 g/L on the 12th day,and the copper dissolution rate of bornite dissolution reached 91.8%on the 24th day.SEM results indicated that the surfaces of pyrite and bornite were significantly corroded by microorganisms.XRD and XPS results showed that ore residues contained jarosite,and the dissolving residue of bornite contained elemental sulfur.The dominant bacterial genus in pyrite dissolution was A.caldus,and L.ferriphilum in bornite dissolution.To sum up,microbes significantly accelerated the mineral dissolution process and promoted the formation of AMD.展开更多
文摘Adult (ADS) and larva stages of palm weevil Rhynchophorus phoenicis were analyzed for their nutritional potentials using proximate and mineral contents as indices. The early larva stage (ELS) contains the highest moisture content of 11.94% while ADS has the least value of 4.79%. The late larva stage (LLS) has the highest protein content of 10.51% while ADS contains 8.43%. Ash content is highest in ELS with a value of 2.37% and lowest in ADS with a value of 1.43%. ELS and LLS have the highest (22.14%) and lowest (17.22%) fibre contents respectively. The values of potassium, magnesium and iron in ELS were (455.00±21.21), (60.69±2.57) and (6.50±3.40) mg/kg while LLS recorded (457.50±10.61), (43.52±1.37) and (6.00±1.10) mg/kg and ADS recorded (372.50±24.75), (53.31±1.88) and (22.90±3.70) mg/kg. Chromium, phosphorus, nickel, calcium, lead, man- ganese and zinc were also detected. Copper was not detected in any of the samples. In all the developmental stages the protein solubilities were pH dependent with the minimum protein solubilities occurring at acidic pH while the maximum protein solu- bilities occurred at alkaline pH.
基金Projects(51934009,52074353)supported by the National Natural Science Foundation of ChinaProject(2019YFC1803600)supported by the National Key Research and Development Program of ChinaProject(2021JJ30855)supported by the Natural Science Foundation of Hunan Province,China。
文摘Acid mine drainage(AMD)has become a widespread environmental issue and its toxicity can cause permanent damage to the ecosystem.However,there are few studies focusing on the formation of AMD under moderately thermophilic conditions,hence we employed X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and 16S rRNA sequencing to study the dissolution of pyrite and bornite by a moderate thermophilic consortium,and explored the role of free and attached microorganisms in the formation of AMD.The consortium mainly comprised Acidithiobacillus caldus,Leptospirillum ferriphilum and Sulfobacillus thermosulfidooxidans.The results indicated that total iron in pyrite solution system reached 33.45 g/L on the 12th day,and the copper dissolution rate of bornite dissolution reached 91.8%on the 24th day.SEM results indicated that the surfaces of pyrite and bornite were significantly corroded by microorganisms.XRD and XPS results showed that ore residues contained jarosite,and the dissolving residue of bornite contained elemental sulfur.The dominant bacterial genus in pyrite dissolution was A.caldus,and L.ferriphilum in bornite dissolution.To sum up,microbes significantly accelerated the mineral dissolution process and promoted the formation of AMD.
