RESUMEN
In the present investigation, crude glycerol derived from transesterification process was utilized to produce the commercially-valuable malic acid. A combined resistant on methanol and malic acid strain of Aspergillus niger MTCC 281 mutant was generated in solid medium containing methanol (1-5%) and malic acid (40-80â¯g/L) by the adaptation process for 22â¯weeks. The ability of induced Aspergillus niger MTCC 281 mutant to utilize crude glycerol and pure glycerol to produce malic acid was studied. The yield of malic acid was increased with 4.45 folds compared with that of parent strain from crude glycerol. The highest concentration of malic acid from crude glycerol by using beneficial mutant was found to be 77.38⯱â¯0.51â¯g/L after 192â¯h at 25⯰C. This present study specified that crude glycerol by-product from biodiesel production could be used for producing high amount of malic acid without any pretreatment.
Asunto(s)
Aspergillus niger , Glicerol , Malatos , Biocombustibles , FermentaciónRESUMEN
INTRODUCTION: Dental fluorosis is considered as a serious public health problem in India. Water is usually the major source of fluoride exposure, but this is not the case always as exposure to local factors like diet can be important in some situations. Earlier studies have shown that jowar (a millet) consumption interacts with fluoride in the body and elevate fluorosis. AIM AND OBJECTIVE: To determine the association between jowar consumption and severity of dental fluorosis. MATERIALS AND METHODS: Hundred schoolgoing children of 10-14 years old was selected by random sampling from Wadloor village. Dental fluorosis was measured in children by Thylstrup-Fejerskov index (1988). Twenty-four hours diet recall method was used to know the exposure to jowar of the children. A pretested questionnaire was given to mother or caretaker to record the jowar consumption. Spot urine samples of children were collected in plastic containers (20 ml) and brought to the laboratory in icebox. Ion selective electrode method was used to measure the fluoride level in urine samples of children. RESULTS: On comparison of the quantity of jowar and fluorosis using Pearson Chi-square test, difference among variable was found out to be statistically significant (P = 0.013, P < 0.05). On comparison of quantity jowar consumption and urinary fluoride level using Pearson Chi-square test, the difference among variable was found statistically significant (P < 0.001). CONCLUSION: Jowar consuming population was positively associated with severity of dental fluorosis.