Kinetics of Phosphate Ions and Phytase Activity Production for Lactic Acid-Producing Bacteria Utilizing Milling and Whitening Stages Rice Bran as Biopolymer Substrates.

A study evaluated nine kinetic data and four kinetic parameters related to growth, production of various phytase activities (PEact), and released phosphate ion concentration ([Pi]) from five lactic acid bacteria (LAB) strains cultivated in three types of media: phytate (IP6), milling stage rice bran (MsRB), and whitening stage rice bran (WsRB). Score ranking techniques were used, combining these kinetic data and parameters to select the most suitable LAB strain for each medium across three cultivation time periods (24, 48, and 72 h). In the IP6 medium, Lacticaseibacillus casei TISTR 1500 exhibited statistically significant highest (p ≤ 0.05) normalized summation scores using a 2:1 weighting between kinetic and parameter data sets. This strain also had the statistically highest levels (p ≤ 0.05) of produced phosphate ion concentration ([Pi]) (0.55 g/L) at 72 h and produced extracellular specific phytase activity (ExSp-PEact) (0.278 U/mgprotein) at 48 h. For the MsRB and WsRB media, Lactiplantibacillus plantarum TISTR 877 performed exceptionally well after 72 h of cultivation. It produced ([Pi], ExSp-PEact) pairs of (0.53 g/L, 0.0790 U/mgprotein) in MsRB and (0.85 g/L, 0.0593 U/mgprotein) in WsRB, respectively. Overall, these findings indicate the most promising LAB strains for each medium and cultivation time based on their ability to produce phosphate ions and extracellular specific phytase activity. The selection process utilized a combination of kinetic data and parameter analysis.

Production of Phenylacetylcarbinol via Biotransformation Using the Co-Culture of Candida tropicalis TISTR 5306 and Saccharomyces cerevisiae TISTR 5606 as the Biocatalyst.

Phenylacetylcarbinol (PAC) is a precursor for the synthesis of several pharmaceuticals, including ephedrine, pseudoephedrine, and norephedrine. PAC is commonly produced through biotransformation using microbial pyruvate decarboxylase (PDC) in the form of frozen-thawed whole cells. However, the lack of microorganisms capable of high PDC activity is the main factor in the production of PAC. In addition, researchers are also looking for ways to utilize agro-industrial residues as an inexpensive carbon source through an integrated biorefinery approach in which sugars can be utilized for bioethanol production and frozen-thawed whole cells for PAC synthesis. In the present study, Candida tropicalis, Saccharomyces cerevisiae, and the co-culture of both strains were compared for their biomass and ethanol concentrations, as well as for their volumetric and specific PDC activities when cultivated in a sugarcane bagasse (SCB) hydrolysate medium (SCBHM). The co-culture that resulted in a higher level of PAC (8.65 ± 0.08 mM) with 26.4 ± 0.9 g L-1 ethanol production was chosen for further experiments. Biomass production was scaled up to 100 L and the kinetic parameters were studied. The biomass harvested from the bioreactor was utilized as frozen-thawed whole cells for the selection of an initial pyruvate (Pyr)-to-benzaldehyde (Bz) concentration ([Pyr]/[Bz]) ratio suitable for the PAC biotransformation in a single-phase emulsion system. The initial [Pyr]/[Bz] at 100/120 mM resulted in higher PAC levels with 10.5 ± 0.2 mM when compared to 200/240 mM (8.60 ± 0.01 mM). A subsequent two-phase emulsion system with Pyr in the aqueous phase, Bz in the organic phase, and frozen-thawed whole cells of the co-culture as the biocatalyst produced a 1.46-fold higher PAC level when compared to a single-phase emulsion system. In addition, the cost analysis strategy indicated preliminary costs of USD 0.82 and 1.01/kg PAC for the single-phase and two-phase emulsion systems, respectively. The results of the present study suggested that the co-culture of C. tropicalis and S. cerevisiae can effectively produce bioethanol and PAC from SCB and would decrease the overall production cost on an industrial scale utilizing the two-phase emulsion system with the proposed multiple-pass strategy.

Extraction of gymnemic acid from Gymnema inodorum (Lour.) Decne. leaves and production of dry powder extract using maltodextrin.

The aim of the present study was to maximize the extraction of gymnemic acid (GA) from Phak Chiang Da (PCD) leaves, an indigenous medicinal plant used for diabetic treatment in Northern Thailand. The goal was to overcome the low concentration of GA in the leaves, which limits its applications among a larger population and develop a process to produce GA-enriched PCD extract powder. The solvent extraction method was employed to extract GA from PCD leaves. The effect of ethanol concentration and extraction temperature were investigated to determine the optimum extraction conditions. A process was developed to produce GA-enriched PCD extract powder, and its properties were characterized. In addition, color analysis (L*, a*, and b*) was performed to evaluate the overall appearance of the PCD extract powder. Antioxidant activity assay was conducted to assess the ability of the PCD extract powder to neutralize DPPH free radicals. The results showed that the concentration of 50% (v/v) ethanol at 70 °C for 2 h resulted in a higher GA concentration of 8307 mg/kg from dried PCD leaves. During the drying process, the use of maltodextrin at a concentration of 0.5% (w/v) was found to produce PCD extract powder with the maximum GA concentration. The color analysis revealed that the PCD extract powder had a dark greenish tint mixed with yellow. The antioxidant activity assay showed that 0.1 g of PCD extract powder was able to neutralize 75.8% of DPPH free radicals. The results concluded that PCD extract powder could potentially be used as a source of nutraceuticals or as a functional food ingredient. These findings suggest the potential value of GA-rich PCD extract powder in various applications in the pharmaceutical, nutraceutical, or food industries.

Enhancement in mechanical and antimicrobial properties of epoxidized natural rubber via reactive blending with chlorhexidine gluconate.

An epoxidized natural rubber (ENR) blend with chlorhexidine gluconate (CHG) was prepared using a two-roll mill at 130 °C. CHG was added at concentrations of 0.2, 0.5, 1, 2, 5, and 10% (w/w) as an antimicrobial additive. The ENR blend with 10% (w/w) CHG showed the best tensile strength, elastic recovery, and Shore A hardness. The ENR/CHG blend exhibited a smooth fracture surface. The appearance of a new peak in the Fourier transform infrared spectrum confirmed that the amino groups of CHG reacted with the epoxy groups of ENR. The ENR with 10% CHG exhibited an inhibition zone against Staphylococcus aureus. The proposed blending improved the mechanical properties, elasticity, morphology, and antimicrobial properties of the ENR.

Valorization of rice straw, sugarcane bagasse and sweet sorghum bagasse for the production of bioethanol and phenylacetylcarbinol.

Open burning of agricultural residues causes numerous complications including particulate matter pollution in the air, soil degradation, global warming and many more. Since they possess bio-conversion potential, agro-industrial residues including sugarcane bagasse (SCB), rice straw (RS), corncob (CC) and sweet sorghum bagasse (SSB) were chosen for the study. Yeast strains, Candida tropicalis, C. shehatae, Saccharomyces cerevisiae, and Kluyveromyces marxianus var. marxianus were compared for their production potential of bioethanol and phenylacetylcarbinol (PAC), an intermediate in the manufacture of crucial pharmaceuticals, namely, ephedrine, and pseudoephedrine. Among the substrates and yeasts evaluated, RS cultivated with C. tropicalis produced significantly (p ≤ 0.05) higher ethanol concentration at 15.3 g L-1 after 24 h cultivation. The product per substrate yield (Yeth/s) was 0.38 g g-1 with the volumetric productivity (Qp) of 0.64 g L-1 h-1 and fermentation efficiency of 73.6% based on a theoretical yield of 0.51 g ethanol/g glucose. C. tropicalis grown in RS medium produced 0.303 U mL-1 pyruvate decarboxylase (PDC), a key enzyme that catalyzes the production of PAC, with a specific activity of 0.400 U mg-1 protein after 24 h cultivation. This present study also compared the whole cells biomass of C. tropicalis with its partially purified PDC preparation for PAC biotransformation. The whole cells C. tropicalis PDC at 1.29 U mL-1 produced an overall concentration of 62.3 mM PAC, which was 68.4% higher when compared to partially purified enzyme preparation. The results suggest that the valorization of lignocellulosic residues into bioethanol and PAC will not only aid in mitigating the environmental challenge posed by their surroundings but also has the potential to improve the bioeconomy.

Pretreatment and enzymatic hydrolysis optimization of lignocellulosic biomass for ethanol, xylitol, and phenylacetylcarbinol co-production using Candida magnoliae.

Cellulosic bioethanol production generally has a higher operating cost due to relatively expensive pretreatment strategies and low efficiency of enzymatic hydrolysis. The production of other high-value chemicals such as xylitol and phenylacetylcarbinol (PAC) is, thus, necessary to offset the cost and promote economic viability. The optimal conditions of diluted sulfuric acid pretreatment under boiling water at 95°C and subsequent enzymatic hydrolysis steps for sugarcane bagasse (SCB), rice straw (RS), and corn cob (CC) were optimized using the response surface methodology via a central composite design to simplify the process on the large-scale production. The optimal pretreatment conditions (diluted sulfuric acid concentration (% w/v), treatment time (min)) for SCB (3.36, 113), RS (3.77, 109), and CC (3.89, 112) and the optimal enzymatic hydrolysis conditions (pretreated solid concentration (% w/v), hydrolysis time (h)) for SCB (12.1, 93), RS (10.9, 61), and CC (12.0, 90) were achieved. CC xylose-rich and CC glucose-rich hydrolysates obtained from the respective optimal condition of pretreatment and enzymatic hydrolysis steps were used for xylitol and ethanol production. The statistically significant highest (p ≤ 0.05) xylitol and ethanol yields were 65% ± 1% and 86% ± 2% using Candida magnoliae TISTR 5664. C. magnoliae could statistically significantly degrade (p ≤ 0.05) the inhibitors previously formed during the pretreatment step, including up to 97% w/w hydroxymethylfurfural, 76% w/w furfural, and completely degraded acetic acid during the xylitol production. This study was the first report using the mixed whole cells harvested from xylitol and ethanol production as a biocatalyst in PAC biotransformation under a two-phase emulsion system (vegetable oil/1 M phosphate (Pi) buffer). PAC concentration could be improved by 2-fold compared to a single-phase emulsion system using only 1 M Pi buffer.

Partially saturated canthaxanthin alleviates aging-associated oxidative stress in D-galactose administered male wistar rats.

It has been earlier reported that partially saturated canthaxanthin (PSC) from Aspergillus carbonarius mutant is non-toxic, has anti-lipid peroxidation activity and can induce apoptosis in prostate cancer cell lines. In the present study, the antiaging effect of PSC was explored in D-galactose administered male wistar rats. 8-10 weeks old, male wistar rats were randomly divided into (i) Vehicle Control Group (VCG), (ii) Aged Control Group (ACG), (iii) Aged + α Lipoic Acid Group (ALG) and (iv) Aged + Partially saturated canthaxanthin Group (APG). Rats received D-galactose (300 mg /kg bwt/day; i.p.) alone (ACG) or together with PSC (APG) (20 mg/kg bwt/day; oral) and α Lipoic Acid (ALG) (80 mg/kg bwt/day; oral) for 10 weeks. Rats in VCG were injected with the same volume of physiological saline (i.p.) and fed with olive oil (vehicle). In vitro protein oxidation and DNA oxidation inhibition, in vivo malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), acetylcholinesterase (AChE) and monoamine oxidase (MAO) activities were determined. In addition, brain neurotransmitters, dopamine and serotonin were estimated by NMR. PSC treatment showed inhibition against protein and DNA oxidation. PSC effectively improved D-galactose induced aging rats by inducing a protective effect through up-regulation of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT) and brain neurotransmitters and downregulated malondialdehyde (MDA) and monoamineoxidase (MAO) levels. Thus, PSC appears to be a functional compound having antioxidant and antiaging properties.

Changes in morphogenesis and carotenogenesis to influence polygalacturonase secretion in Aspergillus carbonarius mutant.

Mycelial morphogenesis and the production of fungal secretory proteins are still largely unknown. A mutant strain of Aspergillus carbonarius UV-10046 produced abundant polygalacturonase (PG) along with partially saturated canthaxanthin (PSC) at low pH conditions. In the present study, the relationship between PG secretion and PSC biosynthesis was studied using carotenogenic inhibitors and SDS-PAGE electrophoresis. Also the correlation between morphogenesis and PG secretion was investigated by analysing through microscopic studies. From the results, it was observed that secretion of PG was positively influenced by the PSC biosynthesis. The results also showed that the mutant with hairy mycelial structure resulted in higher PG activity when compared to the wild type that lacks hyper branching. From the results, it was confirmed that a mutation might have occurred in the isoprenoid pathway that has helped mutant for survival at acidic conditions. Further, an alteration in the morphogenesis and hyper branching development caused over secretion of PG enzyme in the mutant.

The antioxidant effect of mulberry and jamun fruit wines by ameliorating oxidative stress in streptozotocin-induced diabetic Wistar rats.

Polyphenols act by scavenging reactive oxygen species during oxidative stress and hence are useful in the treatment of metabolic disorders including diabetes. This study describes the effect of polyphenol rich mulberry and jamun wines fed to streptozotocin-induced diabetic rats. To male adult Wistar rats, divided into groups (n = 10 per group) intraperitoneal injection was administered with streptozotocin at 38 mg per kg body weight for inducing diabetes. After confirmation of diabetes, rats divided into groups were fed each day with 5.7 milliliter per kg body weight of mulberry, jamun, white and red grape wines for 6 weeks. One group of animals received resveratrol at 20 mg per kg body weight. After six weeks of treatment, blood glucose, urinary profile, lipid profile, plasma, liver, kidney, brain and eye antioxidant enzyme activities, lipid peroxidation, non-esterified fatty acids (NEFA) and hepatic glutathione (GSH) content were determined. Though wine and resveratrol feeding did not improve the glycemic status of diabetic rats, increases in antioxidant enzymes and GSH content accompanied by reduced NEFA and lipid peroxidation were observed. The kidneys and brains of resveratrol fed rats showed significant reduction in malondialdehyde equivalents, exhibited an improved antioxidant status of tissues and an increased glutathione content. The findings suggested that the wines can ameliorate the consequences of diabetes due to their antioxidants.

Resveratrol content and antioxidant properties of underutilized fruits.

In the present study, resveratrol content and antioxidant properties of underutilized fruits such as Jamun (Syzygium cumini L.), Jackfruit (Artocarpus heterophyllus) and Mulberry (Morus rubra) were investigated keeping Grape (Vitis vinifera) as a reference. Ethanol/water (80:20 v/v) extracts of different parts of fruit samples including skin, pulp and seeds were analyzed by HPLC and MS for the quantification of resveratrol. Total polyphenols, flavonoids, DPPH scavenging activity and total antioxidant capacity were also investigated. Among the samples analyzed, mulberry fruit (whole) showed highest resveratrol content (50.61 µg g(-1) dry weight) followed by jamun seed (34.87 µg g(-1) dry weight), jamun pulp (13.70 µg g(-1) dry weight) and skin of jamun (11.19 µg g(-1) dry weight). Jamun seed extract exhibited the highest polyphenol content (55.54 mg gallic acid equivalent g(-1) dry weight) and highest antioxidant property (IC50 value-0.40 mg ml(-1)). The results suggest that underutilized fruits high in resveratrol and other polyphenols can be used as functional beverages.

A short-term toxicity study of Aspergillus carbonarius carotenoid.

In a pharmacokinetic study, high-performance liquid chromatography analysis of blood samples of Wistar female rats fed with partially saturated canthaxanthin (PSC) of Aspergillus carbonarius showed the presence of the carotenoid in the plasma within 6 hours of feeding. In another study for safety assessment of PSC fed to rats over a period of 28 days at 0.05%, 0.10%, and 0.25%, the rats showed no changes in food intake. There were no significant differences observed in body weight, hematological parameters, or serum clinical enzymes compared to the control group not fed with PSC. Deposition of PSC in the eyes of the rats was also not observed. The results showed that PSC-fed rats were not adversely affected as far as toxicological studies were concerned.

Antioxidant and lipid peroxidation activities in rats fed with Aspergillus carbonarius carotenoid.

Effect of feeding partially saturated canthaxanthin (PSC), purified from Aspergillus carbonarius mutant, was studied using four groups of female albino rats (n=6) for 4 weeks. While the control group received basal diet ad libitum, Groups I, II and III were fed with basal diet containing 50, 100 and 250 ppm PSC, respectively. PSC feeding did not cause any significant changes in food intake and there was no gain in body weight either. PSC included in the diet significantly decreased cholesterol in blood. There was 44.75% and 60.54% decrease in LDL-cholesterol in rats fed with 50 and 100 ppm carotenoid. Hepatic ascorbic acid content increased by 44.59% in rats fed with 50 ppm PSC. Dietary PSC at 250 ppm lowered lipid peroxides by 19.49%. Activities of antioxidant enzymes, glutathione transferase and catalase were significantly higher in serum and liver of PSC fed rats compared to the controls. The results suggested that PSC feeding can induce hypocholesterolmic and antioxidant properties in rats.