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The root of Panax notoginseng (Burk.) F.H. is one of the most famous natural medicines and functional foods for numerous diseases. The saponin constituents present in Panax notoginseng leaves (PNGL) demonstrate an elevated level of glycosylation in comparison to those in the roots, resulting in a significantly diminished bioavailability. In this study, we systematically screened nine recombinant thermostable glycosidases and identified a synergistic combination, namely Tpexy3 and Tpebgl3, to catalyze PNGL. At 70 °C, 2000 U of both glycosidases were added before and after 1 g of PNGL, yielding 650 mg of new fractions, of which ginsenosides Rg3, F2, CK, and PPD were identified as the major products. The enzymatic PNGL demonstrated a lipid droplet-lowering effect on the 3 T3-L1 lipid deposition model. Furthermore, the enzymatic PNGL exhibited significant inhibitory effects on weight gain, hyperlipidemia, hyperglycemia, and inflammation in high-fat diet (HFD) mice. Importantly, the enzymatic PNGL restored the HFD-induced increase in the Firmicutes/Bacteroidetes (F/B) ratio and promoted the growth of beneficial gut microbes with anti-inflammatory properties, improved lipid metabolism, and short-chain fatty acid production. These results strongly indicate that enzyme-catalyzed pretreatment of PNGL can effectively enhance its bioavailability and anti-obesity effects. Biological enzyme catalysis not only provides technical support for the development of specific functional products but also promotes the efficient and high-value utilization of natural product resources.

Abstract Background Early detection of hepatocellular carcinoma (HCC) is important in order to improve patient prognosis and survival rate. Methylation sequencing combined with neural networks to identify cell-free DNA (cfDNA) carrying aberrant methylation offers an appealing and non-invasive approach for HCC detection. However, some limitations exist in traditional methylation detection technologies and models, which may impede their performance in the read-level detection of HCC. Methods We developed a low DNA damage and high-fidelity methylation detection method called No End-repair Enzymatic Methyl-seq (NEEM-seq). We further developed a read-level neural detection model called DeepTrace that can better identify HCC-derived sequencing reads through a pre-trained and fine-tuned neural network. After pre-training on 11 million reads from NEEM-seq, DeepTrace was fine-tuned using 1.2 million HCC-derived reads from tumor tissue DNA after noise reduction, and 2.7 million non-tumor reads from non-tumor cfDNA. We validated the model using data from 130 individuals with cfDNA whole-genome NEEM-seq at around 1.6X depth. Results NEEM-seq overcomes the drawbacks of traditional enzymatic methylation sequencing methods by avoiding the introduction of unmethylation errors in cfDNA. DeepTrace outperformed other models in identifying HCC-derived reads and detecting HCC individuals. Based on the whole-genome NEEM-seq data of cfDNA, our model showed high accuracy of 96.2%, sensitivity of 93.6%, and specificity of 98.5% in the validation cohort consisting of 62 HCC patients, 48 liver disease patients, and 20 healthy individuals. In the early stage of HCC (BCLC 0/A and TNM I), the sensitivity of DeepTrace was 89.6 and 89.5% respectively, outperforming Alpha Fetoprotein (AFP) which showed much lower sensitivity in both BCLC 0/A (50.5%) and TNM I (44.7%). Conclusions By combining high-fidelity methylation data from NEEM-seq with the DeepTrace model, our method has great potential for HCC early detection with high sensitivity and specificity, making it potentially suitable for clinical applications. DeepTrace: https://github.com/Bamrock/DeepTrace

Abstract Objective The opportunities for sequencing-based methylome analysis of clinical samples are increasing. To reduce its cost and the amount of genomic DNA required for library preparation, we aimed to establish a capture methyl-seq protocol, which adopts pre-pooling of multiple libraries before hybridization capture and TET2/APOBEC-mediated conversion of unmethylated cytosine to thymine. Results We compared a publicly available dataset generated by the standard Agilent protocol of SureSelect XT Human Methyl-Seq Kit and our dataset obtained by our modified protocol, EMCap, that adopted sample pre-pooling and enzymatic conversion. We confirmed that the quality of DNA methylation data was comparable between the two datasets. As our protocol, EMCap, is more cost-effective and reduces the amount of input genomic DNA, it would serve as a better choice for clinical methylome sequencing.

Background: Early detection of hepatocellular carcinoma (HCC) is important in order to improve patient prognosis and survival rate. Methylation sequencing combined with neural networks to identify cell-free DNA (cfDNA) carrying aberrant methylation offers an appealing and non-invasive approach for HCC detection. However, some limitations exist in traditional methylation detection technologies and models, which may impede their performance in the read-level detection of HCC. Methods: We developed a low DNA damage and high-fidelity methylation detection method called No End-repair Enzymatic Methyl-seq (NEEM-seq). We further developed a read-level neural detection model called DeepTrace that can better identify HCC-derived sequencing reads through a pre-trained and fine-tuned neural network. After pre-training on 11 million reads from NEEM-seq, DeepTrace was fine-tuned using 1.2 million HCC-derived reads from tumor tissue DNA after noise reduction, and 2.7 million non-tumor reads from non-tumor cfDNA. We validated the model using data from 130 individuals with cfDNA whole-genome NEEM-seq at around 1.6X depth. Results: NEEM-seq overcomes the drawbacks of traditional enzymatic methylation sequencing methods by avoiding the introduction of unmethylation errors in cfDNA. DeepTrace outperformed other models in identifying HCC-derived reads and detecting HCC individuals. Based on the whole-genome NEEM-seq data of cfDNA, our model showed high accuracy of 96.2%, sensitivity of 93.6%, and specificity of 98.5% in the validation cohort consisting of 62 HCC patients, 48 liver disease patients, and 20 healthy individuals. In the early stage of HCC (BCLC 0/A and TNM I), the sensitivity of DeepTrace was 89.6 and 89.5% respectively, outperforming Alpha Fetoprotein (AFP) which showed much lower sensitivity in both BCLC 0/A (50.5%) and TNM I (44.7%). Conclusions: By combining high-fidelity methylation data from NEEM-seq with the DeepTrace model, our method has great potential for HCC early detection with high sensitivity and specificity, making it potentially suitable for clinical applications. DeepTrace: https://github.com/Bamrock/DeepTrace [ABSTRACT FROM AUTHOR]

Background: DNA methylation markers are considered robust diagnostic features in various cancer types, as epigenetic marks are commonly altered during cancer progression. Differentiation between benign prostatic hyperplasia (BPH) and early-stage prostate cancer (PCa) is clinically difficult, relying on the information of the patient's symptoms or levels of prostate-specific antigen. Methods: A total of 42 PCa patients and 11 BPH patients were recruited. Genomic DNA was purified from tissues and used for the library preparation of the target-enriched methylome with enzymatic conversion and a Twist 85 Mbp EM-seq panel. Paired-end sequencing (150 bp) was performed using NovaSeq 6000 or NextSeq 550. After quality control, including adapter trimming and de-duplication of raw sequencing data, differential methylation patterns were analyzed between the BPH and PCa groups. Results: We report DNA methylation patterns existing between BPH and PCa. The major finding is that broad hypermethylation occurred at genic loci in PCa tissues as compared to the BPH. Gene ontology analysis suggested that hypermethylation of genic loci involved in chromatin and transcriptional regulation is involved in cancer progression. We also compared PCa tissues with high Gleason scores to tissues with low Gleason scores. The high-Gleason PCa tissues showed hundreds of focal differentially methylated CpG sites corresponding to genes functioning in cancer cell proliferation or metastasis. This suggests that dissecting early-to-advanced-grade cancer stages requires an in-depth analysis of differential methylation at the single CpG site level. Conclusions: Our study reports that enzymatic methylome sequencing data can be used to distinguish PCa from BPH and advanced PCa from early-stage PCa. The stage-specific methylation patterns in this study will be valuable resources for diagnostic purposes as well as further development of liquid biopsy approaches for the early detection of PCa.

β-Alanine is the only naturally occurring β-type amino acid in nature, and it is also one of the very promising three-carbon platform compounds that can be applied in cosmetics and food additives and as a precursor in the chemical, pharmaceutical and material fields, with very broad market prospects. β-Alanine can be synthesized through chemical and biological methods. The chemical synthesis method is relatively well developed, but the reaction conditions are extreme, requiring high temperature and pressure and strongly acidic and alkaline conditions; moreover, there are many byproducts that require high energy consumption. Biological methods have the advantages of product specificity, mild conditions, and simple processes, making them more promising production methods for β-alanine. This paper provides a systematic review of the chemical and biological synthesis pathways, synthesis mechanisms, key synthetic enzymes and factors influencing β-alanine, with a view to providing a reference for the development of a highly efficient and green production process for β-alanine and its industrialization, as well as providing a basis for further innovations in the synthesis of β-alanine.

Malto-oligosaccharides (MOSs) from starch conversion is advantageous for food and pharmaceutical applications. In this study, an efficient malto-oligosaccharide-forming α-amylase AmyCf was identified from myxobacter Cystobacter sp. strain CF23. AmyCf is composed of 417 amino acids with N-terminal 41 amino acids as the signal peptide, and conserved glycoside hydrolase family 13 (GH13) catalytic module and predicted C-terminal domain with β-sheet structure are also identified. Phylogenetic and functional analysis demonstrated that AmyCf is a novel member of GH13_6 subfamily. The special activity of AmyCf toward soluble starch and raw wheat starch is 9249 U/mg and 11 U/mg, respectively. AmyCf has broad substrate specificity toward different types of starches without requiring Ca2+. Under ideal circumstances of 60 °C and pH 7.0, AmyCf hydrolyzes gelatinized starch into maltose and maltotriose and maltotetraose as the main hydrolytic products with more than 80% purity, while maltose and maltotriose are mainly produced from the hydrolysis of raw wheat starch with more than 95% purity. The potential applicability of AmyCf in starch processing is highlighted by its capacity to convert gelatinized starch and raw starch granules into MOSs. This enzymatic conversion technique shows promise for the low-temperature enzymatic conversion of raw starch. [ABSTRACT FROM AUTHOR]

Methylation sequencing is a promising approach to infer the tissue of origin of cell-free DNA (cfDNA). In this study, a single- and a double-stranded library preparation approach were evaluated with respect to their technical biases when applied on cfDNA from plasma and urine. Additionally, tissue of origin (TOO) proportions were evaluated using two deconvolution methods. Sequencing cfDNA from urine using the double-stranded method resulted in a substantial within-read methylation bias and a lower global methylation (56.0% vs. 75.8%, p ≤ 0.0001) compared to plasma cfDNA, both of which were not observed with the single-stranded approach. Individual CpG site-based TOO deconvolution resulted in a significantly increased proportion of undetermined TOO with the double-stranded method (urine: 32.3% vs. 1.9%; plasma: 5.9% vs. 0.04%; p ≤ 0.0001), but no major differences in proportions of individual cell types. In contrast, fragment-level deconvolution led to multiple cell types, with significantly different TOO proportions between the two methods. This study thus outlines potential limitations of double-stranded library preparation for methylation analysis of cfDNA especially for urinary cfDNA. While the double-stranded method allows jagged end analysis in addition to TOO analysis, it leads to significant methylation bias in urinary cfDNA, which single-stranded methods can overcome. [ABSTRACT FROM AUTHOR]

Objective: The opportunities for sequencing-based methylome analysis of clinical samples are increasing. To reduce its cost and the amount of genomic DNA required for library preparation, we aimed to establish a capture methyl-seq protocol, which adopts pre-pooling of multiple libraries before hybridization capture and TET2/APOBEC-mediated conversion of unmethylated cytosine to thymine. Results: We compared a publicly available dataset generated by the standard Agilent protocol of SureSelect XT Human Methyl-Seq Kit and our dataset obtained by our modified protocol, EMCap, that adopted sample pre-pooling and enzymatic conversion. We confirmed that the quality of DNA methylation data was comparable between the two datasets. As our protocol, EMCap, is more cost-effective and reduces the amount of input genomic DNA, it would serve as a better choice for clinical methylome sequencing. [ABSTRACT FROM AUTHOR]

In view of the problems of low yield of enzymatic conversion of ginsenoside Rb1 in traditional buffer solution, low solubility of intermediates and slow enzymatic conversion rate, ginsenoside Rb1 was converted by deep eutectic solvent auxiliary enzymatic method. The effects of DES types and mass concentration, pH value, temperature, enzyme-substrate mass ratio and reaction time on CK yield were investigated, and the optimal conditions for the conversion reaction were obtained in DES buffer with pH=5.3, the mass ratio of snail enzyme to substrate was 1∶1, and the yield of CK could reach 87.92% at 50 ℃ and the reaction for 36 h. The method of dissolving ginsenosides in DES solvent for enzymatic conversion was adopted, which can better increase the solubility of ginsenosides, enhance the secondary structure of enzymes, and improve the yield of CK, the preparation process is environmentally friendly, safe and suitable for industrial production.

In traditional oriental medicine, carrots (Daucus carota L.) are considered effective medicinal herbs; however, the use of D. carota leaves (DCL) as therapeutic agents has not been explored in depth. Therefore, we aimed to demonstrate the value of DCL, generally treated as waste while developing plants for wide industrial availability. Six flavone glycosides were isolated and identified from DCL, and their constituents were identified and quantitated using an NMR and HPLC/UV method, which was optimized and validated. The structure of chrysoeriol-7-rutinoside from DCL was elucidated for the first time. The method exhibited adequate relative standard deviation (<1.89%) and recovery (94.89–105.97%). The deglycosylation of DCL flavone glycosides by Viscozyme L and Pectinex was assessed. Upon converting the reaction contents to percentages, the luteolin, apigenin, and chrysoeriol groups showed values of 85.8, 33.1, and 88.7%, respectively. The enzyme-treated DCL had a higher inhibitory effect on TNF-α and IL-2 expression than that of the carrot roots or carrot leaves without enzyme treatments. These results highlight the importance of carrot leaves and could be used as baseline standardization data for commercial development. [ABSTRACT FROM AUTHOR]

In view of the problems of low yield of enzymatic conversion of ginsenoside Rb1 in traditional buffer solution, low solubility of intermediates and slow enzymatic conversion rate, ginsenoside Rb1 was converted by deep eutectic solvent auxiliary enzymatic method. The effects of DES types and mass concentration, pH value, temperature, enzyme-substrate mass ratio and reaction time on CK yield were investigated, and the optimal conditions for the conversion reaction were obtained in DES buffer with pH=5.3, the mass ratio of snail enzyme to substrate was 1∶1, and the yield of CK could reach 87.92% at 50 ℃ and the reaction for 36 h. The method of dissolving ginsenosides in DES solvent for enzymatic conversion was adopted, which can better increase the solubility of ginsenosides, enhance the secondary structure of enzymes, and improve the yield of CK, the preparation process is environmentally friendly, safe and suitable for industrial production. [ABSTRACT FROM AUTHOR]

γ-Cyclodextrin (γ-CD) is an attractive material among the natural cyclodextrins owing to its excellent properties. γ-CD is primarily produced from starch by γ-cyclodextrin glycosyltransferase (γ-CGTase) in a controlled system. However, difficulty in separation and low conversion rate leads to high production costs for γ-CD. In this study, γ-CGTase from Bacillus sp. G-825-6 STB17 was used in γ-CD production from cassava starch. With the introduction of sodium tetraphenylborate (NaBPh 4), the total conversion rate was promoted from an initial 18.07 % to 50.49 % and the γ-CD ratio reached 78.81 % with a yield of 39.79 g/L. Furthermore, the mechanism was conducted via the determination of binding constant, which indicated that γ-CD exhibited much stronger binding strength with NaBPh 4 than β-CD. The reformation of water molecules and the chaotropic effect might be the main driving forces for the interaction. Additionally, the conformations of CD complexes were depicted by NMR and molecular docking. The results further verified different binding patterns between CDs and tetraphenylborate ions, which might be the primary reason for the specific binding. This system not only guides γ-CD production with an efficient and easy-to-remove production aid but also offers a new perspective on the selection of complexing agents in CD production. [Display omitted] [ABSTRACT FROM AUTHOR]

Passion fruit peel contained various phenolic compounds with α-glucosidase and α-amylase inhibitory activities in vitro. However, the bound state and glycosylated forms hindered their active expression. In this article, β-glucosidase-producing Lactobacilli were inoculated into fermented peels for targeted metabolism. The results showed that the release of bound polyphenols and the increase of free polyphenols were significantly correlated with β-glucosidase activity. The strain G1 with high enzyme activity degraded 48.20% of the bound polyphenols after 24 h. The ability of extracts to inhibit α-glucosidase and α-amylase activities was significantly enhanced and closely related to the content of free polyphenols (r = −0.96 and −0.88, P < 0.001). Computer-assisted screening identified 38 phenolic compounds as potential dual inhibitors of α-glucosidase and α-amylase. Among them, 22 α-glucosidase inhibitors and 24 α-amylase inhibitors were identified for the first time. Various inhibitors, including phenolic acids, flavones, and flavonols, increased in content after fermentation. The total content of 14 glycosylated polyphenols decreased to 28.38% at 48 h, which was opposite to the aglycone. Molecular docking indicated that glycosylated polyphenols bind to β-glucosidase through hydrogen bonds and van der Waals forces. Different glycosylations at the C-3 position of quercetin bound at same sites to β-glucosidase. This study contributes to the theory of enhancing the functional activity of natural products through targeted fermentation transformation. [ABSTRACT FROM AUTHOR]

Hydrothermal pretreatment (HTP) has long been considered as an efficient and green treatment process on lignocellulosic biomass for bioconversion. However, the variations of cellulose supramolecular structures during HTP as well as their effects on subsequent enzymatic conversion are less understood. In this work, bamboo holocellulose with well-connected cellulose and hemicelluloses polysaccharides were hydrothermally treated under various temperatures. Chemical, morphological, and crystal structural determinations were performed systematically by a series of advanced characterizations. Xylan was degraded to xylooligosaccharides in the hydrolyzates accompanied by the reduced degree of polymerization for cellulose. Cellulose crystallites were found to swell anisotropically, despite the limited decrystallization by HTP. Hydrogen bond linkages between cellulose molecular chains were weakened due to above chemical and crystal variations, which therefore swelled, loosened, and separated the condensed cellulose microfibrils. Samples after HTP present notably increased surface area, favoring the adsorption and subsequent hydrolysis by cellulase enzymes. A satisfying enzymatic conversion yield (>85%) at rather low cellulase enzyme dosage (10 FPU/g glucan) was obtained, which would indicate new understandings on the green and efficient bioconversion process on lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

Geranyl esters (GEs) are valuable monoterpene esters derived from the esterification of geraniol and various carboxylic acids with a range of unique aromas and properties, making them valuable in perfumery, pharmaceutical, and cosmetic applications. Lipase-mediated esterification is considered to be a sustainable process but is challenged by the lack of a compatible catalytic method in conjunction with a customized microbial biosynthesis of geraniol. In this study, we developed an integrated process to convert glycerol and various carboxylates into GEs. The process includes microbial biosynthesis of geraniol using metabolically engineered Escherichia coli and enzymatic conversion of geraniol into GEs in a fermentation medium-organic biphasic system using an immobilized lipase. The enzymatic step for esterifying the target carboxylates with geraniol achieved >90% conversion under the optimized condition. Coupled with the geraniol from microbial fermentation, 0.59 g/L geranyl butyrate and 1.04 g/L geranyl hexanoate were produced subsequently, demonstrating the feasibility of converting renewable source into monoterpene esters through this integrated process, which bypassed feeding extra geraniol in the conventional lipase-mediated GE synthesis.

Malto-oligosaccharides (MOSs) from starch conversion is advantageous for food and pharmaceutical applications. In this study, an efficient malto-oligosaccharide-forming α-amylase AmyCf was identified from myxobacter Cystobacter sp. strain CF23. AmyCf is composed of 417 amino acids with N-terminal 41 amino acids as the signal peptide, and conserved glycoside hydrolase family 13 (GH13) catalytic module and predicted C-terminal domain with β-sheet structure are also identified. Phylogenetic and functional analysis demonstrated that AmyCf is a novel member of GH13_6 subfamily. The special activity of AmyCf toward soluble starch and raw wheat starch is 9249 U/mg and 11 U/mg, respectively. AmyCf has broad substrate specificity toward different types of starches without requiring Ca2+. Under ideal circumstances of 60 °C and pH 7.0, AmyCf hydrolyzes gelatinized starch into maltose and maltotriose and maltotetraose as the main hydrolytic products with more than 80% purity, while maltose and maltotriose are mainly produced from the hydrolysis of raw wheat starch with more than 95% purity. The potential applicability of AmyCf in starch processing is highlighted by its capacity to convert gelatinized starch and raw starch granules into MOSs. This enzymatic conversion technique shows promise for the low-temperature enzymatic conversion of raw starch.

Methylation sequencing is a promising approach to infer the tissue of origin of cell-free DNA (cfDNA). In this study, a single- and a double-stranded library preparation approach were evaluated with respect to their technical biases when applied on cfDNA from plasma and urine. Additionally, tissue of origin (TOO) proportions were evaluated using two deconvolution methods. Sequencing cfDNA from urine using the double-stranded method resulted in a substantial within-read methylation bias and a lower global methylation (56.0% vs. 75.8%, p ≤ 0.0001) compared to plasma cfDNA, both of which were not observed with the single-stranded approach. Individual CpG site-based TOO deconvolution resulted in a significantly increased proportion of undetermined TOO with the double-stranded method (urine: 32.3% vs. 1.9%; plasma: 5.9% vs. 0.04%; p ≤ 0.0001), but no major differences in proportions of individual cell types. In contrast, fragment-level deconvolution led to multiple cell types, with significantly different TOO proportions between the two methods. This study thus outlines potential limitations of double-stranded library preparation for methylation analysis of cfDNA especially for urinary cfDNA. While the double-stranded method allows jagged end analysis in addition to TOO analysis, it leads to significant methylation bias in urinary cfDNA, which single-stranded methods can overcome.

The occurrence of emerging contaminants, such as estrogens, in secondary and tertiary treated effluents and in sewage-impacted water bodies is one of the major obstacles to the implementation of water reuse. This review critically evaluates the performance of emerging process of enzymatic degradation of estrogens, and its efficiency. The data collected from peer-review literature show that enzymes have been extensively applied (in both free and immobilized form) in estrogen removal. Amongst others, the use of laccase as a catalyst provides over 90% removal of estrogens. Immobilized enzymes can overcome some limitations of the free biocatalysts, including reusability. Research evidence points to the formation of by-products, such as dimers and trimers. Nevertheless, estrogenic activity assessment indicates a reduction in toxicity after enzyme treatment. The cost and stability of enzymes, as well as their performance in a real wastewater matrix, are the major obstacles to the implementation of enzymatic processes in wastewater treatment. Continued endeavors are required to enhance the successful application of enzymes in the wastewater treatment industry. Processes of enzyme-supported conversion of estrogens are reviewed and discussed. Laccase is the most commonly applied enzyme and achieves over 90% estrogen removal. Immobilization is suggested as an effective tool for enhancement of estrogen removal. Dimers and trimers have been identified as main bioconversion products of estrogens. Existing research gaps are highlighted and future recommendations are provided. [ABSTRACT FROM AUTHOR]

The sugar beet industry is rooted firmly in the trade and agricultural policies of the European powers during the nineteenth century. Disruption of sugar importation into Europe triggered staggering advancements around a home-grown sugar crop based on a newly developed technology out of Lower Silesia. This resulted in today's well-established sugar beet industry that has since spread to all corners of the globe. Over the years, effort has been focused on the improvement of crop output, the reduction of processing costs and energy requirements, as well as the valorization of co-products. Today's industry has started the evolution toward sustainability and a circular economy and is currently gaining momentum. Some high-level scientific research is being transferred to the industry as witness to this process, and it is one of the most exciting times to be part of this realm in Europe. Sugar beet is a near-optimal feedstock for numerous chemical and biochemical products. Not only does it contains an array of valuable and extractable compounds, but it can also serve as a raw material for virtually limitless transformations. This is largely due to accelerating developments in enzymatic, fermentation and synthetic biotechnologies. In a world where sustainability has become a key focus, the sugar beet will continue to play an ever-important role. [ABSTRACT FROM AUTHOR]

Rare sugars are of great interest as alternative sweeteners because they are beneficial for human health and have a high industrial value. The existence of rare sugars in nature in very limited quantities has encouraged studies to convert common sugars obtained from plants into rare sugars by enzymatic, chemical or other methods. D-allulose, which has a very important place among rare sugars, is a sugar that stands out with its low calorie and sweetness very close to sucrose. It has the ability to regulate many biological functions such as lowering blood glucose level, improving insulin resistance, reducing fat accumulation in the body and reducing fever, as well as having high solubility and positive effects on food tissue, making the use of this sugar more efficient in food processing. D-allulose is known as "indigestible carbohydrate". It occurs naturally in many fruits and beverages and some cereal products. Today, D-allulose can be produced in many ways such as plant extraction, chemical synthesis, enzymatic conversion and can be safely used in the production of some foodstuffs. In this review, D-allulose production methods are presented, differences in these methods and their advantages and disadvantages are compared to each other. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soda pretreatment with redox mediator was successfully upscaled in a 20 L reactor. • Black liquor combustion met process energy demand with 21.11 MJ energy surplus. • Low lignin content in pretreated material favored fed-batch with low enzyme load. • Total reducing sugars (142 g L−1) closer to ideal for autonomous 2G distilleries. • Co-fermentation of C5 and C6 sugars simultaneously produced 61.3 g L−1 2G ethanol. This study presents the upscaling of soda pretreatment of sugarcane bagasse (SB) using a new redox mediator (2-hydroxynaphthalene-1,4-dione) obtained from renewable resources, which does not affect enzymatic hydrolysis and fermentation. Upscaling was performed from a 0.5 L batch static stainless steel reactor to a 20 L pulp digester with forced liquor circulation, analogous to digestors used in the pulp and paper industry. Enzymatic hydrolysis of the pretreated material was optimized using the fed-batch method and was then carried out on a larger scale. The fed-batch method, combined with addition of 1 % (v v−1) Tween 80, enabled the solids load to be increased from 10 % to 15 % (w v−1), with an enzyme load of only 3.00 FPU g−1. This led to a maximum total reducing sugars concentration of ∼142 g L−1 after 72 h of hydrolysis. Co-fermentation of C5 and C6 sugar-rich hydrolysate by a consortium of CERLEV 47 (Saccharomyces cerevisiae) and CERLEV 1015 (Pichia guilliermondii) led to a maximum 2G ethanol production of 61.3 g L−1 (308 L ethanol per ton of SB). Mass and energy balances demonstrated that the combustion of black liquor, a byproduct of the soda pretreatment, could satisfy the energy demands of the pretreatment, enzymatic hydrolysis, and fermentation, with an energy of 21.11 MJ using the surplus SB (80 %) from 1G ethanol production. This finding indicated that the developed process was robust and had the potential to enhance total 2G ethanol production. This study supports the feasibility of an integrated 1G/2G biorefinery by improving energy efficiency, economic viability, and environmental sustainability. [ABSTRACT FROM AUTHOR]

In traditional oriental medicine, carrots (Daucus carota L.) are considered effective medicinal herbs; however, the use of D. carota leaves (DCL) as therapeutic agents has not been explored in depth. Therefore, we aimed to demonstrate the value of DCL, generally treated as waste while developing plants for wide industrial availability. Six flavone glycosides were isolated and identified from DCL, and their constituents were identified and quantitated using an NMR and HPLC/UV method, which was optimized and validated. The structure of chrysoeriol-7-rutinoside from DCL was elucidated for the first time. The method exhibited adequate relative standard deviation (

Deep eutectic solvents (DESs) hold great potential in biorefining because they can efficiently deconstruct the recalcitrant structure of lignocellulose. In particular, inorganic salts with Lewis acids have been proven to be effective at cleaving lignin–carbohydrate complexes. Herein, a Zr-based DES system composed of metal chloride hydrate (ZrOCl 2 ·8H 2 O) and ethylene glycol (EG) was designed and used for poplar powder pretreatment. Zr4+-based salts provide sufficient acidity for lignocellulose depolymerization. The acidity of the DES was analysed by the Kamlet-Taft solvatochromic parameter, and the results demonstrated that the acidity can be regulated by the DES composition. Under the optimum conditions (ZrOCl 2 ·8H 2 O:EG molar ratio of 1:2), the DES pretreatment removes nearly 100 % hemicellulose and 94.7 % lignin. The recovered lignin exhibited a low polydispersity of 1.7. The cellulose residues deliver an efficiency of 94.4 % upon enzymatic digestion. Moreover, the DES can be easily recovered with high yield and purity, and the recycled DES still maintains high delignification and enzymatic hydrolysis efficiencies. The proposed DES pretreatment technology is promising for biomass valorization. [Display omitted] [ABSTRACT FROM AUTHOR]

Lactose is the most abundant by-product of the dairy industry and is increasingly recognized as an important feedstock to produce value-added compounds. Lactulose and epilactose are valuable prebiotics that can be generated from lactose with cellobiose 2-epimerases (CEases). Here we describe the characterization of the two CEases CbCEP and RfCEP, originated from the thermophilic microorganism Caldicellulosiruptor bescii and the mesophilic microorganism Roseburia faecis, respectively. CbCEP showed exceptional pH and temperature stability, with maximal activity at pH 7.5 and 70 °C. RfCEP exhibited maximum activity at 50 °C and pH 8. Under optimal conditions in small-scale experiments with commercial lactose, CbCEP produced both lactulose and epilactose with yields of 29.8% and 21.6%, respectively, while RfCEP produced only epilactose with a yield of 19.3%. Furthermore, we evaluated the application of CbCEP for lactulose and epilactose production in stirred fermenters at two different temperatures (70 and 30 °C) at a scale of 5 L volume and a concentration of cheese-whey permeate of 50 g/L. At 70 °C, lactulose was the predominant product of CbCEP-mediated lactose conversion, with a final yield of 30% (12.8 g/L) lactulose and 24.7% (10.6 g/L) epilactose. At 30 °C, lactose was mainly converted into epilactose, with a final yield of 35% (14.9 g/L), and a minor amount of lactulose (final yield of 4.3%, 1.8 g/L). The findings presented here may guide the design of an industrial strategy, based on the temperature-tunable activity of CbCEP, for production of valuable lactose derivatives at high yields directly from whey permeate.

BACKGROUND Coffee husk (CH) is the main agricultural solid waste generated during the coffee bean dry processing. Therefore, it is necessary to investigate other alternatives for the more noble use of this by‐product, adding value to it considering the circular economy concept within the coffee production chain. This study aimed to add value to CH by liquid hot water (LHW) pretreatment as an alternative to improve the enzymatic conversion of polysaccharides of this substrate to fermentable sugars through enzymatic hydrolysis. RESULTS: Box–Behnken experimental design was used to evaluate the effect of LHW pretreatment on the enzymatic hydrolysis yield (EHY), investigating the independent variables time (t), temperature (T), and liquid‐to‐solid ratio (LSR). The desirable condition (200 °C, 41 min, LSR of 5 mL g−1) was selected as the most suitable for the enzymatic hydrolysis, reaching an EHY value of 75.3% with an enzyme load of 40 FPU g PCH−1. The alkaline extraction step applied to pretreated coffee husk (PCH) was not effective to improve the EHY, as the cellulose fraction was not preserved. Two reloads of solids were considered an ideal condition, reaching an EHY value of 69.1% after 24 h of hydrolysis with a total enzyme load of 27 FPU g PCH−1. CONCLUSION: The liquid hot water of CHs associated with the reload of solids on enzymatic hydrolysis is an interesting alternative to reduce the cost with enzyme cocktail and hydrolysis time, thus making the process more feasible for technology upscaling. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The activity of rare saponins is generally better than that of their prototypes. There are significant differences in the proportions and pharmacological effects of rare saponins/prototype saponins in Gynostemma pentaphyllum samples dried with different methods, which may be related to the reaction catalyzed by glucosidase. To explore the pattern of the enzymatic reaction catalyzed by glucosidase during the processing of G. pentaphyllum and provide technical support for the green production of rare saponins, this experiment extracted glucosidase from fresh leaves of G. pentaphyllum, constructed a simulated reaction system, and conducted in vitro simulation reactions with the prototype saponins extract of G. pentaphyllum. Ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry was employed to detect the substrates, intermediate products, and final products of the reaction. Furthermore, traditional Chinese medicine chemical methods were used to purify and identify some substrates and products, on the basis of which the enzymatic reaction pattern was explored. The results confirmed the role of gypenoside-β-glucosidase in the enzymatic reaction and identified a total of 15 saponins, including PPD neutral saponins and acidic saponins(acetyl saponins, malonyl saponins, etc.,) in 4 groups during the reaction process. Four substrates and products were purified and identified, and it was clarified that gypenoside-β-glucosidase had selectivity. The enzymatic reaction pattern was summarized as follows.(1)The enzyme only hydrolyzed neutral saponins, while acidic saponins such as acetyl and malonyl saponins were not easily hydrolyzed.(2)The hydrolysis occurred at the glucosyl group at the C-3 position, while the glucosyl group at the C-20 position was not easily hydrolyzed. The enzymatic reaction of G. pentaphyllum can be employed to generate rare saponins, and the findings of this study can help expand and enhance the utilization value of G. pentaphyllum.

In this study, lactose in milk is converted to galacto-oligosaccharides (GOS) using β-gal from Kluveromyces lactis. Trans-galactosylation was done by adding 1 mL of β-gal in 1L milk at 42°C for 2 hours with continuous agitation. Subsequently, the cheese prepared from the GOS enriched milk and control milk were compared for the physico-chemical and organoleptic properties. The chemical composition of prebiotic cheese exhibited non-significant differences for the fat, protein, moisture and ash, whereas a significantly lower level of lactose (56.25%) was observed as compared to control cheese. Organoleptic evaluation showed that the prebiotic cheese has a similar appearance and overall acceptability as does the control cheese except for taste and texture which were improved by trans-glycosylation.

[Display omitted] • Using glycosidase has altered the characteristics of high glycosylation and low bioavailability of Panax notoginseng leaf triterpenes. • Through biocatalysis, the directional conversation of ginsenosides in Panax notoginseng leaves to rare ginsenosides with anti-obesity properties and improved impact on gut microbiota in mice. • This has brought about significant economic and social benefits for the reutilization of Panax notoginseng leaves. The root of Panax notoginseng (Burk.) F.H. is one of the most famous natural medicines and functional foods for numerous diseases. The saponin constituents present in Panax notoginseng leaves (PNGL) demonstrate an elevated level of glycosylation in comparison to those in the roots, resulting in a significantly diminished bioavailability. In this study, we systematically screened nine recombinant thermostable glycosidases and identified a synergistic combination, namely Tpexy3 and Tpebgl3, to catalyze PNGL. At 70 °C, 2000 U of both glycosidases were added before and after 1 g of PNGL, yielding 650 mg of new fractions, of which ginsenosides Rg 3 , F 2 , CK, and PPD were identified as the major products. The enzymatic PNGL demonstrated a lipid droplet-lowering effect on the 3 T3-L1 lipid deposition model. Furthermore, the enzymatic PNGL exhibited significant inhibitory effects on weight gain, hyperlipidemia, hyperglycemia, and inflammation in high-fat diet (HFD) mice. Importantly, the enzymatic PNGL restored the HFD-induced increase in the Firmicutes/Bacteroidetes (F/B) ratio and promoted the growth of beneficial gut microbes with anti-inflammatory properties, improved lipid metabolism, and short-chain fatty acid production. These results strongly indicate that enzyme-catalyzed pretreatment of PNGL can effectively enhance its bioavailability and anti-obesity effects. Biological enzyme catalysis not only provides technical support for the development of specific functional products but also promotes the efficient and high-value utilization of natural product resources. [ABSTRACT FROM AUTHOR]

Chitinases play crucial roles in enzymatic conversion of chitin and biocontrol of phytopathogenic fungi. Herein, a chitinase of glycoside hydrolase (GH) family 19, Sa ChiB, was cloned from Streptomyces alfalfae ACCC 40021 and expressed in Escherichia coli BL21(DE3). The purified Sa ChiB displayed maximal activities at 45 °C and pH 8.0, and showed good stability up to 55 °C and in the range of pH 4.0–11.0, respectively. It exhibited substrate specificity towards chitin and chitooligosaccharides (degree of polymerization 3–6) with the endo -cleavage manner. In combination with the N -acetyl hexosaminidase Sa HEX, it yielded a conversion rate of 95.2% from chitin powder to N -acetyl-D-glucosamine in 8 h and a product purity of >98.5%. Furthermore, the enzyme strongly inhibited the growth of tested pathogenic fungi. These results indicated that Sa ChiB has the great potential for applications in the conversion of raw chitinous waste in industries as well as the biocontrol of fungal diseases in agriculture. Unlabelled Image [ABSTRACT FROM AUTHOR]

The enzymatic conversion of lignins, possibly in combination with electrochemical oxidation, makes aromatics such as syringol, guaiacol, vanillin and catechol available in the qualities required by the fragrance industry. The lignins were obtained by soda digestion from wheat straw and Miscanthus, characterized and then converted with laccases. The overall yield amounted up to 9 wt % with a product spectrum confined to four substances. Catechol was the major product, with a fraction of ≈75 %. It can easily be isolated by extraction with acetone. [ABSTRACT FROM AUTHOR]

Levulinic acid (LA) is an important chemical building block listed among the top 12 value-added chemicals by the United States Department of Energy, and can be obtained through the hydrolysis of lignocellulosic biomass. Using the same approach as in the catalytic production of LA from biomass, catalytic methods to upgrade LA to higher value chemicals have been investigated. Since the discovery of the catabolic genes and enzymes in the LA metabolic pathway, bioconversion of LA into useful chemicals has attracted attention, and can potentially broaden the range of biochemical products derived from cellulosic biomass. With a brief introduction to the LA catabolic pathway in Pseudomonas spp., this review summarizes the current studies on the microbial conversion of LA into bioproducts, including the recent developments to achieve higher yields through genetic engineering of Escherichia coli cells. Three different types of reactions during the enzymatic conversion of LA are also discussed. Key points: • Levulinic acid is an alternative building block to sugars from cellulosic biomass. • Introduction of levulinic acid bioconversion with natural and engineered microbes. • Initial enzymatic conversion of levulinic acid proceeds via three different pathways. • 4-Hydroxyvalerate is one of the target chemicals for levulinic acid bioconversion. [ABSTRACT FROM AUTHOR]

Partially purified ginsenoside extract (PGE) and compound K enriched extract (CKE) were prepared from ginseng sprouts, and their antioxidant, anti-inflammatory and antithrombotic effects were investigated. Compared to the 6-year-old ginseng roots, ginseng sprouts were found to have a higher content of phenolic compounds, saponin and protopanaxadiol-type ginsenoside by about 56%, 36% and 43%, respectively. PGE was prepared using a macroporous adsorption resin, and compound K(CK) was converted and enriched from the PGE by enzymatic hydrolysis with a conversion rate of 75%. PGE showed higher effects than CKE on radical scavenging activity in antioxidant assays. On the other hand, CKE reduced nitric oxide levels more effectively than PGE in RAW 264.7 cells. CKE also reduced pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-1β and IL-6 than PGE. Tail bleeding time and volume were investigated after administration of CKE at 70–150 mg/kg/day to mice. CKE administered group showed a significant increase or increased tendency in bleeding time than the control group. Bleeding volume in the CKE group increased than the control group, but not as much as in the aspirin group. In conclusion, ginseng sprouts could be an efficient source of ginsenoside, and CKE converted from the ginsenosides showed antioxidant, anti-inflammatory and antithrombotic effects. However, it was estimated that the CKE might play an essential role in anti-inflammatory effects rather than antioxidant effects.

N -Acetyl- d -glucosamine (GlcNAc) is a valuable monosaccharide widely used in the medical, agricultural, biofuel, and food industries. Its efficient and environment-friendly production depends on the binary system of β- N -acetylhexosaminidase (HEX) and chitinase. In the present study, a HEX of glycoside hydrolasefamily 20 was identified in Streptomyces alfalfae ACCC40021, and was overexpressed in Escherichia coli. The purified recombinant Sa HEX showed maximal activities at 60°C and pH 5.5, and retained stable up to 45°C. The enzyme not only exhibited broad substrate specificity including p -nitrophenyl β- N -acetylglucosaminide, p -nitrophenyl β- N -acetylgalactosaminide, chitooligosaccharides and colloidal chitin, but also had higher specific activities (up to 1149.7 ± 72.6 U/mg) towards natural and synthetic substrates. When combined with a commercial chitinase, it achieved a conversion rate of 93.7% from 1% of colloidal chitin to GlcNAc in 6 h, with the product purity of >98%. These excellent properties make Sa HEX a potential enzyme candidate for the chitin conversion for various industrial purposes. Image 1 • A β- N -acetylhexosaminidase from Streptomyces alfalfae was cloned and overexpressed in Escherichia coli BL21 (DE3). • The purified recombinant Sa HEX showed maximal activity at 60 °C and pH 5.5, and stable up to 45°C. • The enzyme has broad substrate specificity including long-chain polysaccharide colloidal chitin. • In combination with a chitinase from Streptomyces griseus , it converted 93.2% of colloidal chitin to GlcNAc in 6 h. • These excellent properties make Sa HEX superior over other reported HEXs for potential applications in various industries. [ABSTRACT FROM AUTHOR]

Despite enormous progress in protein engineering, complemented by bioprocess engineering, the revolution awaiting the application of biocatalysis in the fine chemical industry has still not been fully realized. In order to achieve that, further research is required on several topics, including (1) rapid methods for protein engineering using machine learning, (2) mathematical modelling of multi-enzyme cascade processes, (3) process standardization, (4) continuous process technology, (5) methods to identify improvements required to achieve industrial implementation, (6) downstream processing, (7) enzyme stability modelling and prediction, as well as (8) new reactor technology. In this brief mini-review, the status of each of these topics will be briefly discussed. [ABSTRACT FROM AUTHOR]

Exploration and application of novel and sustainable deep eutectic solvents (DESs) on lignocellulose pretreatment are promising approaches to efficient bioconversion. However, comprehensive understanding on efficient DESs selection and inner mechanisms of lignocellulose deconstruction are still limited. Herein, bio-based acetylcholine chloride (AChCl) was firstly utilized as hydrogen bond acceptor in cooperation with lactic acid, urea and glycerol respectively for microwave-assisted pretreatment on moso bamboo in short time. High enzymatic conversion yield of bamboo cellulose (∼85%) was achieved by lactic acid-AChCl DES due to its lower pH value and viscosity, followed by glycerol-AChCl and urea-AChCl DES. In addition to the features of proposed DESs, changed chemical and physical properties of highly recalcitrant bamboo biomass after pretreatments were systematically determined. Besides of great amount of lignin (∼90%)/ xylan (100%) removal, micro- to nano-scale variations of cellulose structures including more dissociated microfibrils, lowered crystallinity, and enlarged crystallite sizes all played key roles in promoting bioconversion yields. Moreover, the multi-factors contributing to improved hydrolysis performance were integrated to evaluate the effects of novel DESs pretreatments on lignocellulose deconstruction, which may provide new strategies on bioconversion enhancement and process optimization. [Display omitted] • Acetylcholine chloride was firstly served as HBA for fast DES treatment on bamboo. • Boosted enzymatic conversion yield of 85% was achieved for AL-10 and AL-20. • Multi-factors inhibiting enzymatic conversion of biomass were summarized. • Cellulose supramolecular structures are key factors impacting the glucose yield. [ABSTRACT FROM AUTHOR]

In this study, the structural modification of Siam weed (Chromolaena odorata) was performed using NaOH–H2O2- and Ca(OH)2–H2O2-based oxidative pretreatment for the enzymatic conversion of the biomass to a biocommodity, reducing sugar (RS). Pretreatment of raw sample was evaluated at temperatures of 60°C, 70°C, 80°C, 90°C for different time intervals of 3, 6, 9, 12 h in alkaline medium (NaOH or Ca(OH)2). The effects of pretreatment time and temperature were considered in obtaining the optimum conditions. The optimum conditions for NaOH–H2O2 was obtained at 70°C and 3 h with a maximum cellulose content of 44.29%(w/w), lignin content reduced to 21.09% from the initial raw value of 24.2%. Pretreatment with Ca(OH)2–H2O2 resulted in the optimum conditions obtained to be 70°C for 3 h with a cellulose content of 47.18%. Enzymatic hydrolysis on the pretreated biomass at the optimum conditions showed NaOH–H2O2-treated sample yielded 424.35 mg equivalent glucose/g biomass of RS while Ca(OH)2–H2O2-treated sample yielded 335.81 mg equivalent glucose/g biomass of RS. The untreated raw sample yielded 68.75 mg equivalent glucose/g biomass of RS. Consequently, NaOH–H2O2 pretreatment displayed a higher efficiency than Ca(OH)2–H2O2 pretreatment. Stereomicroscopic and scanning electron microscopic imaging of the treated and untreated samples revealed morphological disruptions brought about by the treatments.

β-Alanine is the only naturally occurring β-type amino acid in nature, and it is also one of the very promising three-carbon platform compounds that can be applied in cosmetics and food additives and as a precursor in the chemical, pharmaceutical and material fields, with very broad market prospects. β-Alanine can be synthesized through chemical and biological methods. The chemical synthesis method is relatively well developed, but the reaction conditions are extreme, requiring high temperature and pressure and strongly acidic and alkaline conditions; moreover, there are many byproducts that require high energy consumption. Biological methods have the advantages of product specificity, mild conditions, and simple processes, making them more promising production methods for β-alanine. This paper provides a systematic review of the chemical and biological synthesis pathways, synthesis mechanisms, key synthetic enzymes and factors influencing β-alanine, with a view to providing a reference for the development of a highly efficient and green production process for β-alanine and its industrialization, as well as providing a basis for further innovations in the synthesis of β-alanine., Competing Interests: PS and SW were employed by Shandong Aobo Biotech Co. Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Song, Zhang, Wang, Xu and Wei.)

Gypenoside XLVI (gyp XLVI) is one of the major dammarane-type triterpenoid saponins from Gynostamma pentaphallum with glucosyls at C-3 and C-20 positions, which may constrain its bioactivities. The enzymatic conversion of gyp XLVI by naringinase, and the cytotoxicity of enzymolysis product on SMMC7721 and Bel7402 hepatoma cells were investigated. The results showed that gynosaponin TN-1 (gyp TN-1) was produced from the enzymatic conversion of gyp XLVI by naringinase. The optimum enzymolysis conditions were pH 4.2, 47.3 °C, and 16 h, with a yield of 73.44 ± 6.52% for gyp TN-1. In addition, gyp TN-1 exhibited higher inhibitory activities on SMMC7721 and Bel7402 hepatoma cells than gyp XLVI. Results from methyl thiazolyl tetrazolium (MTT) assay and acridine orange (AO)/ethidium bromide (EB) double staining were highly consistent. These results demonstrated that enzymatic conversion could be a promising method for producing gyp TN-1 from the biotransformation of gyp XLVI and the preparation of gyp TN-1 might provide a reference for the acquisition of novel anticancer drugs. [ABSTRACT FROM AUTHOR]

This study investigated the behaviour of key aroma compounds in the presence of human saliva (200 μL) from different individuals ( n = 3) submitted or not to centrifugation (whole vs clarified saliva). HS-GC results showed that human saliva strongly decreased the release of carbonyl compounds (aldehydes and ketones). This effect was dependent on i) the structure of the aroma compounds and ii) the saliva composition. Whole saliva exerted a higher effect than clarified saliva on aroma compounds. Moreover, this effect was individual-dependent and related to the total protein content and the total antioxidant capacity of saliva. HS-SPME and LLE-GC/MS analyses revealed that metabolism of the compounds by salivary enzymes was involved. This observation indicates that some aroma compounds could be metabolized in the oral cavity in an individual manner, which could have implications for aroma perception (e.g., formation of new metabolites with different odor thresholds and qualities) and/or organisms’ health status (e.g., compound detoxification). [ABSTRACT FROM AUTHOR]

Chitin is an abundant polysaccharide primarily produced as an industrial waste stream during the processing of crustaceans. Despite the limited applications of chitin, there is interest from the medical, agrochemical, food and cosmetic industries because it can be converted into chitosan and partially acetylated chitosan oligomers (COS). These molecules have various useful properties, including antimicrobial and anti-inflammatory activities. The chemical production of COS is environmentally hazardous and it is difficult to control the degree of polymerization and acetylation. These issues can be addressed by using specific enzymes, particularly chitinases, chitosanases and chitin deacetylases, which yield better-defined chitosan and COS mixtures. In this review, we summarize recent chemical and enzymatic approaches for the production of chitosan and COS. We also discuss a design-of-experiments approach for process optimization that could help to enhance enzymatic processes in terms of product yield and product characteristics. This may allow the production of novel COS structures with unique functional properties to further expand the applications of these diverse bioactive molecules.

The need for natural antimicrobials with reference to food preservation and food safety highlights the importance of vegetable fats that can be an essential source of fatty acids with antimicrobial properties. The hydrolysis of raw palm fat was evaluated using the in vitro solid state cultivation of eight strains of Yarrowia lipolytica . Therefore, the solid state enzymatic conversion of raw fat at different water activity values and time periods (up to 7 days) was performed. The best results were obtained with Y. lipolytica MIUG D14 at 25 °C, a w 0.98, after 7 days of solid state cultivation. The free fatty acids profile was analyzed by GC-MS and the results revealed a higher concentration of some acids, recognized for their antimicrobial effects, i.e 50% palmitic acid (C16:0), 20% linoleic acid (C18:2) and over 6% for the lauric (C12:0) and myristic (C14:0) acids. The results revealed that under controlled conditions, the solid state enzymatic conversion of raw palm is an effective method for free fatty acids with antimicrobial activity production, at reduced costs. This process can be successfully used for obtaining a biopreservation effect in various applications in food industry and related fields, such as cosmetics. [ABSTRACT FROM AUTHOR]