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1.
Crit Rev Food Sci Nutr ; 63(29): 10047-10078, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35531939

RESUMO

The enantiomeric pure and natural (+)-Lactones (C ≤ 14) with aromas obtained from fruits and milk are considered flavoring compounds. The flavoring value is related to the lactones' ring size and chain length, which blend in varying concentrations to produce different stone-fruit flavors. The nature-identical and enantiomeric pure (+)-lactones are only produced through whole-cell biotransformation of yeast. The industrially important γ-decalactone and δ-decalactone are produced by a four-step aerobic-oxidation of ricinoleic acid (RA) following the lactonization mechanism. Recently, metabolic engineering strategies have opened up new possibilities for increasing productivity. Another strategy for increasing yield is to immobilize the RA and remove lactones from the broth regularly. Besides flavor impact, γ-, δ-, ε-, ω-lactones of the carbon chain (C8-C12), the macro-lactones and their derivatives are vital in pharmaceuticals and healthcare. These analogues are isolated from natural sources or commercially produced via biotransformation and chemical synthesis processes for medicinal use or as active pharmaceutical ingredients. The various approaches to biotransformation have been discussed in this review to generate more prospects from a commercial point of view. Finally, this work will be regarded as a magical brick capable of containing both traditional and genetic engineering technology while contributing to a wide range of commercial applications.


Assuntos
Lactonas , Engenharia Metabólica , Lactonas/química , Lactonas/metabolismo , Biotransformação , Oxirredução , Saccharomyces cerevisiae/metabolismo
2.
J Biotechnol ; 393: 17-30, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39025368

RESUMO

Ricinoleic acid (RA) from castor oil was employed in biotransformation of peach-flavoured γ-decalactone (GDL), using a Candida parapsilosis strain (MTCC13027) which was isolated from waste of pineapple crown base. Using four variables-pH, cell density, amount of RA, and temperature-the biotransformation parameters were optimized using RSM and BBD. Under optimized conditions (pH 6, 10 % of microbial cells, 10 g/L RA at 28°C), the conversion was maximum and resulted to 80 % (+)-GDL (4.4 g/L/120 h) yield in shake flask (500 mL). Furthermore, optimization was achieved by adjusting the aeration and agitation parameters in a 3 L bioreactor, which were then replicated in a 10 L bioreactor to accurately determine the amount of (+)-GDL. In bioreactor condition, 4.7 g/L (>85 %) of (+)-GDL is produced with 20 % and 40 % dissolved oxygen (1.0 vvm) at 150 rpm in 72 h and 66 h, respectively. Further, a new Al-Mg-Ca-Si composite column-chromatography method is developed to purify enantiospecific (+)-GDL (99.9 %). This (+)-GDL is 100 % nature-identical as validated through 14C-radio-carbon dating. Thorough chemical investigation of enantiospecific (+)-GDL is authenticated for its use as flavour. This bioflavour has been developed through a cost-effective biotechnological process in response to the demand from the food industry on commercial scale.


Assuntos
Reatores Biológicos , Candida parapsilosis , Óleo de Rícino , Lactonas , Ácidos Ricinoleicos , Ácidos Ricinoleicos/metabolismo , Ácidos Ricinoleicos/química , Reatores Biológicos/microbiologia , Óleo de Rícino/química , Óleo de Rícino/metabolismo , Candida parapsilosis/metabolismo , Lactonas/metabolismo , Lactonas/química , Aromatizantes/metabolismo , Aromatizantes/química , Biotransformação
3.
J Biotechnol ; 377: 34-42, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37848135

RESUMO

Flavour molecules are generated now-a-days through microbial fermentation on a commercial scale. γ-Decalactone (GDL) is an important molecule due to its long-lasting flavouring impact as buttery, coconut and peach-type. In the current study, 33 microorganisms were isolated from different fruit sources, and their screening for target GDL production was performed. Using DNA sequencing, two potential strains yielding good amounts of GDL were identified from pineapple and strawberry fruits. The identified strains were Metschnikowia vanudenii (OP954735) and Candida parapsilosis (OP954733), and further optimized by Taguchi method. The effectiveness of lactone production is influenced by the rate of microbial growth under various operating conditions. The factors such as substrate concentration, pH, temperature, cell density and rotation (rpm) with 3 levels were applied for the GDL production using M. vanudenii (OP954735) and C. parapsilosis (OP954733) strains. The results revealed that the highest molar conversion of GDL was 24.69% (115.7 mg/g quantitative yield) and 52.69% (272.0 mg/g quantitative yield) at the optimal conditions using SB-62 and PA-19 strains, respectively. The two novel strains are reported for the first time for production of γ-decalactone and overall, this study opens up the possibility of using Taguchi design for large scale up process development for producing food flavours utilising environmentally friendly natural strains.


Assuntos
Lactonas , Leveduras , Leveduras/genética , Leveduras/metabolismo , Lactonas/química , Biotransformação
4.
J Clin Diagn Res ; 9(1): TC21-4, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25738057

RESUMO

INTRODUCTION: Developmental delay is defined as significant delay in one or more developmental domains. Magnetic Resonance Imaging (MRI) is the best modality to investigate such patients. Evaluation of a child with developmental delay is important not only because it allows early diagnosis and treatment but also helpful for parental counseling regarding the outcome of their child and to identify any possible risk of recurrence in the siblings. Thus this study was undertaken to evaluate the developmental delay in Indian children which will help the clinicians in providing an estimation of the child's ultimate developmental potential and organize specific treatment requirement and also relieve parental apprehension. AIMS AND OBJECTIVES: To study the prevalence of normal and abnormal MRI in pediatric patients presenting with developmental delay and further categorize the abnormal MRI based on its morphological features. MATERIALS AND METHODS: It is a prospective, observational & descriptive study of MRI Brain in 81 paediatric patients (46 Males and 35 Females), aged between three months to 12 years; presenting with developmental delay in Deccan College of Medical Sciences, Hyderabad; over a period of three years (Sept 2011 to Sept 2014). MRI brain was done on 1.5T Siemens Magnetom Essenza & 0.35T Magnetom C with appropriate sequences and planes after making the child sleep/sedated/ anesthetized. Various anatomical structures like Ventricles, Corpus callosum, etc were systematically assessed. The MRI findings were divided into various aetiological subgroups. RESULTS: Normal MRI findings were seen in 32% cases and 68% had abnormal findings of which the proportion of Traumatic/ Neurovascular Diseases, Congenital & Developmental, Metabolic and Degenerative, neoplastic and non specific were 31%, 17%, 10%, 2.5% and 7.5% respectively. The ventricles and white matter mainly the corpus callosum were the most commonly affected anatomical structures. The diagnostic yield was found to be 68% and higher yield was seen in patients presenting with developmental delay plus. CONCLUSION: The clinical diagnosis of developmental delay should not be the end point, but rather a springboard for an effective search for causal factors. MRI is the best investigation with a high yield in such patients.

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