L-Cysteine hydrochloride monohydrate

Green Synthesis of Crystalline Silica from Sugarcane Bagasse Ash: Physico-Chemical Properties.[Pubmed:35808020]

Nanomaterials (Basel). 2022 Jun 25;12(13):2184.

Sugarcane bagasse South Africa is an agricultural waste that poses many environmental and human health problems. Sugarcane bagasse dumps attract many insects that harm the health of the population and cause many diseases. Sugarcane ash is a naturally renewable source of silica. This study presents for the first time the extraction of nanosilica from sugar cane bagasse ash using L-Cysteine hydrochloride monohydrate acid and Tetrapropylammonium Hydroxide. The structural, morphological, and chemical properties of the extracted silica nanoparticles was cross examined using XRD, FTIR, SEM, and TGA. SEM analysis presents agglomerates of irregular sizes. It is possible to observe the structure of nanosilica formed by the presence of agglomerates of irregular shapes, as well as the presence of some spherical particles distributed in the structure. XRD analysis has revealed 2theta angles at 20, 26, 36, 39, 50, and 59 which shows that each peak on the xrd pattern is indicative of certain crystalline cubic phases of nanosilica, similar to results reported in the literature by Jagadesh et al. in 2015. The crystallite size estimated by the Scherrer equation based on the aforementioned peaks for ca-silica and L-cys-silica for the extracted particles had an average diameter of 26 nm and 29 nm, respectively. Furthermore, it showed a specific surface area of 21.6511 m(2)/g and 116.005 m(2)/g for ca-silica and L-cys silica, respectively. The Infrared (IR) spectra showed peaks at 461.231 cm(-1), 787.381 cm(-1) and 1045.99 cm(-1) which corresponds to the Si~O~Si bending vibration, the Si~O~Si stretch vibration, and the Si~O~Si stretching vibration, respectively. This confirms the successful extraction of nanosilica from sugar cane bagasse ash. TGA analysis has revealed that the as received sugarcane bagasse has high loss on ignition (LOI) of 18%, corresponding to the presence of the unburnt or partial burnt particles, similar to results reported by Yadav et al. This study has shown that sugar cane bagasse ash is a natural resource of silica which should be harnessed for industrial purposes in south Africa.

Safety and efficacy of l-cysteine monohydrochloride monohydrate produced by fermentation using Escherichia coli KCCM 80109 and Escherichia coli KCCM 80197 for all animal species.[Pubmed:32874303]

EFSA J. 2020 Apr 30;18(4):e06101.

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of l-cysteine monohydrochloride monohydrate produced by fermentation using two non-genetically modified strains of Escherichia coli K12 (E. coli KCCM 80109 and E. coli KCCM 80197) as a flavouring additive for all animal species. No safety concerns are derived from the use of these strains as production strains of the additive. The FEEDAP Panel concludes that the use of L-Cysteine hydrochloride monohydrate produced by E. coli KCCM 80109 and KCCM 80197 at concentrations up to 25 mg/kg complete feed is safe for the target species, for the consumer and for the environment. The product is proposed to be classified as respiratory irritant; however, exposure by inhalation is unlikely. Based on the results of the studies provided, it should be classified as skin irritant and that it causes serious eye damage. L-Cysteine hydrochloride monohydrate is not a dermal sensitiser. Since L-Cysteine hydrochloride monohydrate is used in food as flavourings, it is to be expected that it can provide a similar function in feed and no further demonstration of efficacy is necessary when used at concentrations up to 25 mg/kg complete feed and the corresponding concentration in water.

Safety and efficacy of l-cysteine hydrochloride monohydrate produced by fermentation using Escherichia coli KCCM 80180 and Escherichia coli KCCM 80181 as a flavouring additive for all animal species.[Pubmed:32874218]

EFSA J. 2020 Feb 10;18(2):e06003.

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of l-cysteine monohydrochloride monohydrate produced by fermentation using two genetically modified strains of Escherichia coli K12 (Escherichia coli KCCM 80180 and Escherichia coli KCCM 80181) as a flavouring additive for all animal species. No safety concerns are derived from the use of these strains as production strains of the additive. The FEEDAP Panel concludes that L-Cysteine hydrochloride monohydrate, produced by E.coli KCCM 80180 and KCCM 80181 at concentrations up to 25 mg/kg complete feed, is safe for the target species, for the consumer and for the environment. The product is proposed to be classified as respiratory irritant; however, exposure by inhalation is unlikely. L-Cysteine hydrochloride monohydrate produced by E.coli KCCM 80180 and E.coli KCCM 80181 was shown to be a skin and eye irritant but not a skin sensitiser. Since L-Cysteine hydrochloride monohydrate is used in food as flavouring, it is to be expected that it can provide a similar function in feed and no further demonstration of efficacy is necessary when used at concentrations up to 25 mg/kg complete feed and the corresponding concentration in water.