Total Reducing Sugars Research Articles

Valorisation of the invasive alga Rugulopteryx okamurae through the production of monomeric sugars

Rugulopteryx okamurae is an invasive brown alga causing severe environmental and economic problems on the western Mediterranean coasts. Thus, in addition to the difficulties caused to the fishing and tourism sectors, there is a need to manage its accumulation on the beaches. This work aims to valorise this waste by using it as raw material for producing monosaccharides through a two-stage sequential process. These sugars could be used for different fermentative processes to obtain high-value-added bioproducts. In this work, biological pretreatment of the previously conditioned seaweed with the fungus Aspergillus awamori in solid-state fermentation (SSF), followed by enzymatic hydrolysis with a commercial enzyme cocktail, was performed. The effect of the extension of the biological pretreatment (2, 5, 8 and 12 days) on the subsequent release of total reducing sugars (TRS) in the enzymatic hydrolysis stage was studied. To analyse this effect, experimental data of TRS produced along the hydrolysis were fitted to simple first-order kinetics. Also, the secretion of cellulase and alginate lyase by the fungus, along with the biological pretreatment, was determined. The results suggest that 5 days of biological pretreatment of the macroalgae with A. awamori followed by enzymatic saccharification for 24 h with Cellic CTec2® (112 FP units/g of dry biomass) are the best conditions tested, allowing the production of around 240 g of TRS per kg of dried biomass. The main sugars obtained were glucose (95.8 %) and mannitol (1.5 %), followed by galactose (1 %), arabinose (0.9 %) and fucose (0.5 %).Key points• Five-day SSF by A. awamori was the best condition to pretreat R. okamurae.• Five-day SSF was optimal for alginate lyase production (1.63 ±0.011 IU/g biomass).• A maximum yield of 239 mg TRS/g biomass was obtained (with 95.8 % glucose).Graphical

Hydrolysis of cassava's (Manihot esculenta Crantz) waste polysaccharides using the natural zeolite Stilbite-Ca as catalyst

Agribusiness produces a large amount of organic waste, such as by-products of lignocellulosic and starch biomasses, which are often discarded incorrectly, leading to environmental problems. This paper aims to study the catalyzed hydrolysis of Manihot esculenta Crantz (cassava) using natural zeolite as heterogeneous catalyst. The biomass and zeolite characterization were analyzed according to their physical-chemical properties. Cassava waste presented 70.66 % of starch, which indicates its potential to yield high added-value products such as fermentable sugar, dextrin, and 5-hydroxymethylfurfural. X-ray diffraction, Fourier-transform infrared, scanning electron microscopy with energy dispersive, and X-ray fluorescence analysis of the natural zeolite showed a mineralogical composition of Stilbite-Ca. According to these material's properties, the natural zeolite was applied to the catalysis of cassava waste. It presents 86.53 % of conversion in 6 h producing 17.77 % of total reducing sugars, which was superior to the hydrolysis reaction only with water.

Investigation of a robust pretreatment technique based on ultrasound-assisted, cost-effective ionic liquid for enhancing saccharification and bioethanol production from wheat straw

Application of cost-effective pretreatment of wheat straw is an important stage for massive bioethanol production. A new approach is aimed to enhance the pretreatment of wheat straw by using low-cost ionic liquid [TEA][HSO4] coupled with ultrasound irradiation. The pretreatment was conducted both at room temperature and at 130 °C with a high biomass loading rate of 20% and 20% wt water assisted by ultrasound at 100 W-24 kHz for 15 and 30 min. Wheat straw pretreated at 130 °C for 15 and 30 min had high delignification rates of 67.8% and 74.9%, respectively, and hemicellulose removal rates of 47.0% and 52.2%. Moreover, this pretreatment resulted in producing total reducing sugars of 24.5 and 32.1 mg/mL in enzymatic saccharification, respectively, which corresponds to saccharification yields of 67.7% and 79.8% with commercial cellulase enzyme CelluMax for 72 h. The ethanol generation rates of 38.9 and 42.0 g/L were attained for pretreated samples for 15 and 30 min, equivalent to the yields of 76.1% and 82.2% of the maximum theoretical yield following 48 h of fermentation. This demonstration provided a cheap and promising pretreatment technology in terms of efficiency and shortening the pretreatment time based on applying low-cost ionic liquid and efficient ultrasound pretreatment techniques, which facilitated the feasibility of this approach and could further develop the future of biorefinery.

Flagging defensive roles of carbohydrate-active enzymes (CAZymes) and carbohydrates during Puccinia triticina-wheat interactions

Puccinia triticina (Pt) infects wheat, leading to colonization of leaf tissues, pustule formation on the leaf and eventually yield loss. Fungicides and breeding techniques are used to manage Pt infection in wheat. However, there is a growing need for biochemical studies to identify critical metabolites and proteins that contribute to plant susceptibility or resistance against Pt. The current study investigated defensive role of non-structural, structural carbohydrates, and CAZymes during Pt-wheat interaction at 1, 7, and 14 days post inoculation (dpi). The results revealed that glucose, total reducing sugars and sucrose were significantly decreased by more than 50% in Pt inoculated susceptible Thatcher (IS) plants. Sucrose concentrations decreased by 0.80 and 0.93 fold in IS compared to control sample (CS) at 1 and 7 dpi. Pt inoculated resistant Thatcher + Lr9 (IR) plants and control (CR) did not display differences in soluble carbohydrate concentrations. In addition, exoglucanase, endoglucanase, pectinase and carbohydrate esterase activities were significantly higher at 1 or 7 dpi in IS compared to IR plants. The cellulose-content was 29% in IR samples compared to 15% in CR samples at 14 dpi. Additionally, hemicellulose increased by 2% in IR at 14 dpi. The cell wall reinforcements in resistant plants were supported by Fourier transformation infrared results that revealed that IR holocellulose content was not affected by Pt infection, but IS samples holocellulose decreased at 7 dpi. In conclusion, increased activities of CAZymes, decreased cell wall holocellulose content, and reduced soluble carbohydrates were susceptibility indicators.

Simultaneous saccharification of hemicellulose and cellulose of corncob in a one-pot system using catalysis of carbon based solid acid from lignosulfonate.

The drive towards sustainable chemistry has inspired the development of active solid acids as catalysts and ionic liquids as solvents for an efficient release of sugars from lignocellulosic biomass for future biorefinery practices. Carbon-based solid acid (SI-C-S-H2O2) prepared from sodium lignosulfonate, a waste of the paper industry, was used with water or ionic liquid to hydrolyze corncob in this study. The effects of various reaction parameters were investigated in different solvent systems. The highest xylose yield of 83.4% and hemicellulose removal rate of 90.6% were obtained in an aqueous system at 130 °C for 14 h. After the pretreatment, cellulase was used for the hydrolysis of residue and the enzymatic digestibility of 92.6% was obtained. Following these two hydrolysis steps in the aqueous systems, the highest yield of total reducing sugar (TRS) was obtained at 88.1%. Further, one-step depolymerization and saccharification of corncob hemicellulose and cellulose to reducing sugars in an IL-water system catalyzed by SI-C-S-H2O2 was conducted at 130 °C for 10 h, with a high TRS yield of 75.1% obtained directly. After recycling five times, the solid acid catalyst still showed a high catalytic activity for sugar yield in different systems, providing a green and effective method for lignocellulose degradation.

The Study of the Heterogeneity of the Qualities of Argan Oils and Pomaces from Different Cooperatives in the Essaouira Region (Morocco)

In this study, a comparison of the intra-regional variation in the quality of Argan oil and pomace collected from 12 cooperatives in the Essaouira region (Morocco) during the COVID-19 period was carried out. All studied Argan pomaces together with the extraction solvents showed a significant difference (p ≤ 0.05) in the total phenolic compounds, flavonoids, and tannins contents. The proteins, residual oils, total sugars, and total reducing sugars contents in the collected pomaces vary considerably among cooperatives of origin, with maximum averages of 50.45%; 30.05%; 3.82 milligrams of glucose equivalent per gram of dry matter; and 0.53 milligrams of glucose equivalent per gram of dry matter, respectively. Therefore, it is a very valuable ingredient for livestock feed and some cosmetic products that may contain it. The remaining Argan oil content in the pomace varied significantly among cooperatives, ranging from 8.74 to 30.05%. Pomace from traditional extraction recorded the highest content (30.05%), showing that the artisanal and modern extraction processes are not standardized. The measurements of acidity, peroxide value, specific extinction coefficient at 232 nm and 270 nm, and conjugated dienes were carried out in accordance with Moroccan Standard 08.5.090 in order to qualitatively classify all investigated Argan oils. Accordingly, the analyzed oils were categorized as "extra virgin Argan oil," "fine virgin Argan oil," "ordinary virgin Argan oil," and "lampante virgin Argan oil." Therefore, several factors can explain these variations in quality grades, both endogenous and exogenous. Overall, the variation observed in the obtained result allows us to deduce the most significant variables impacting the quality of Argan products and by-products.

Evaluating the Prebiotic Potential of Lepidium Sativum Seed Mucilage as a Nutraceutical Ingredient

The current study investigates the prebiotic potential of Lepidium sativum L. seeds mucilage on different lactobacilli strains. The quantification of the total reducing sugar in the mucilage was attained by Ultraviolet-Visible Spectrophotometric method. The mucilage exhibited efficient resistance against α-amylase and artificial gastric juice hydrolysis compared to standard prebiotic inulin. The mucilage also exhibited efficient activity necessary for the augmentation of almost all strains of lactobacilli. In vitro studies also exhibited that lactobacilli amount was at par to standard prebiotics (p<0.05) in the medium supplemented with the mucilage. The study led to conclude that the seed mucilage of Lepidium sativum exhibits efficient prebiotic activity and thereby can be used as a potential functional nutraceutical supplement.

Determination of Chemical Parameters of Fruits Available in the Markets of Pokhara, Nepal

The main objective of this paper is to determine the chemical parameters: pH, optical density (OD), electrical conductivity (EC), percentage of moisture content, total ash, silica, dietary fiber, total acid, vitamin C, total reducing sugar, and formaldehyde content, of selected fruits (apple, banana, coconut, grape, litchi, mango, mousambi, papaya, pineapple, pomegranate and watermelon) available in the markets of Pokhara. Chemical parameters were analyzed by using standard methods in the Research Laboratory of Prithvi Narayan Campus Pokhara, Nepal from 15th March 2022 to 14th June 2022. The pH content ranged from 3.17 to 5.40 indicating acidic nature of all the fruit juices. Electrical conductivity was maximum for coconut juice (818 μS cm–1) followed by pomegranate, grape, mousambi and pineapple whereas that of mango was minimum (246 μS cm–1). Maximum to minimum value of moisture content, total ash, dietary fiber, titratable acidity and vitamin C were from 93.59% (for watermelon) to 72.80% (for coconut), 1.705% (for banana) to 0.360% (for watermelon), 4.52% (for coconut) to 0.35% (for watermelon), 0.098368% (for coconut) to 0.022448% (for watermelon), and 0.049354% (for mousambi) to 0.004121% (for grape) respectively. The highest value for total reducing sugar was recorded in Papaya (2.913269%) whereas lowest value observed in coconut (0.2106619%). Washable formaldehyde content was ranged from 0.01942085% (for grape) to 0.00038287% (for watermelon). The observed chemical parameters of fresh fruits as analyzed by using standard methods are in agreement with previously published values. This study shows that fruit samples are nutritious and fit for fresh eating by consumers.

Pretreatment with a combination of steam explosion and NaOH increases butanol production of enzymatically hydrolyzed corn stover

As an essential lignocellulosic source, corn stover (CS) arouses an extensive interest in transforming into bio-butanol and high-value-added products. Optimization experiments of medium and kinetic fermentation experiments of Clostridium acetobutylicum CICC 8008 were conducted. The CS was pretreated by a combination of steam explosion and NaOH, followed by saccharification by cellulase. The saccharification liquor contained 65.91 g/L of total reducing sugar. The optimum fermentation medium was 1,000 mL saccharification liquor supplemented with 4.89 g/L yeast extract, 6.9 g/L CaCO3, and 10.56 mg/L biotin. When the optimum medium was used in the butanol fermentation process, the maximum acetone-butanol-ethanol (ABE) content was 41.78 g/L, and the contents of acetone, butanol, and ethanol were 9.73, 23.82, and 8.23 g/L, respectively. The maximum specific growth rate was 0.066 h−1, the coefficient of growth was 2.29 g/(gL), and no substrate and production inhibition were found. ABE was the growth-associated metabolite. Collectively, our current findings provided valuable insights into the efficient application of lignocellulose biomass into the biorefinery of butanol.

Optimization of Solid-State Fermentation of Switchgrass Using White-Rot Fungi for Biofuel Production

Biological delignification using white-rot fungi is a possible approach in the pretreatment of lignocellulosic biomass. Despite the considerable promise of this low-input, environmentally-friendly pretreatment strategy, its large-scale application is still limited. Therefore, understanding the best combination of factors which affect biological pretreatment and its impact on enzymatic hydrolysis is essential for its commercialization. The present study was conducted to evaluate the impact of fungal pretreatment on the enzymatic digestibility of switchgrass under solid-state fermentation (SSF) using Phanerochaete chrysosporium (PC), Trametes versicolor 52J (Tv 52J), and a mutant strain of Trametes versicolor that is cellobiose dehydrogenase-deficient (Tv m4D). Response surface methodology and analysis of variance (ANOVA) were employed to ascertain the optimum pretreatment conditions and the effects of pretreatment factors on delignification, cellulose loss, and total available carbohydrate (TAC). Pretreatment with Tv m4D gave the highest TAC (73.4%), while the highest delignification (23.6%) was observed in the PC-treated sample. Fermentation temperature significantly affected the response variables for the wild-type fungal strains, while fermentation time was the main significant factor for Tv m4D. The result of enzymatic hydrolysis with fungus-treated switchgrass at optimum pretreatment conditions showed that pretreatment with the white-rot fungi enhanced enzymatic digestibility with wild-type T. versicolor (52J)-treated switchgrass, yielding approximately 64.9% and 74% more total reducing sugar before and after densification, respectively, than the untreated switchgrass sample. Pretreatment using PC and Tv 52J at low severity positively contributed to enzymatic digestibility but resulted in switchgrass pellets with low unit density and tensile strength compared to the pellets from the untreated switchgrass.

Squalene rich virgin palm oil by microwave-assisted enzyme aqueous extraction from palm mesocarp

Microwave-assisted enzyme aqueous (MAEA) technique may improve the concentration of squalene in virgin palm oil (VPO). However, the efficiency of different enzyme compositions in various MAEA reaction conditions has yet to be determined. Therefore, the activity of four types of enzymes, hemicellulase, cellulase, pectinase, and phospholipase, and their mixture under various MAEA reaction conditions, including enzyme concentration (0,1 and 2%), pH (4.5 and 8), and incubation time (0, 2 and 4 h) were evaluated and its effect on the oil yield, squalene content, total reducing sugar and fatty acid composition of VPO was evaluated. The squalene content and fatty acids composition were analyzed using GC-FID. The results showed that MAEA significantly increased the oil yield and squalene content compared to aqueous extraction (AE), microwave aqueous extraction (MA) and enzyme aqueous extraction (EAE). The highest oil yield (39.48 ± 4.03%) was obtained from mixed enzymes at pH 4.5, and the highest squalene content (961.77 ± 53.16 mg/100 g) was obtained from mixed enzyme at pH 8. Microwave pre-treatment in enzyme aqueous extraction also significantly reduces the extraction time. VPO obtained from MAEA has higher lauric acid content. Overall, the best reaction condition to produce squalene rich VPO is by using 2% mixed enzyme, pH 8 and 4 h of incubation time. The results showed that MAEA extraction techniques are feasible for producing a high concentration of squalene in VPO as functional food products.

Sustainable Total Reducing Sugar Production by Waste Printed Power Board Derived Zn–Zr Photocatalyst

Sustainable Total Reducing Sugar Production by Waste Printed Power Board Derived Zn–Zr Photocatalyst

Determination of Physical-chemical Parameters in Bee Products: A Preliminary Investigation from Africa’s Most Renewed Bee Village in Tanzania

Aim: The main objective of this study was to evaluate the determination of physical-chemical parameters in bee products: a preliminary investigation from Africa’s most renewed bee village in Tanzania; specifically, the study presents preliminary findings of an inquiry that examined pesticide contamination in bee products from Kijiji cha Nyuki located in Tanzania. The study measured the levels of physical-chemical parameters in honey products harvested from the selected bee apiaries.
 Material and Methods: A mixed methods approach was adopted for this study and collected data both primary and secondary data were collected using physical observation and survey, interviews, and questionnaires, purposive and random sampling techniques were used in this study to select a total of 104 participants who was taken as a sample from universal populations. Qualitative and quantitative data were analyzed using IBM Statistical Package for Social Sciences (SPSS) Computer Programme version 25, where the statistics aspect was determined from the results obtained from both questionnaires and laboratory experiments. A preliminary investigation from Africa’s most renewed bee village in Tanzania; Collected samples were analyzed at TBS & SGS laboratories.
 Results: The results show all studied areas met honey quality assurance guidelines stipulated by the ministry of natural resources and tourism suggesting moisture content in honey should not exceed 21%. pH test showed honey sample from Egypt apiaries had higher pH of 4.3 and honey from Kijiji cha Nyuki had a low pH of 3.54 implying honey from the studied areas falls within the pH applicable range. Test of Hydroxylmethly furfural mg/kg discovered an average of 13.65 mg/kg in honey samples from 4 studied areas out of the 5, with 107.13 mg/kg of HMF in honey samples from Egypt. Suggesting that honey samples from the 4 study areas with exception of samples from Egypt met the TZS 851:2006 standards and national’s guidelines of 40mg/kg Hydroxylmethly furfural. Finally, the Test of total reducing sugar as inverted sugar % m/m, from five samples as per Tanzania Bureau of Statistics (TBS) laboratory results found a maximum of 68.91 % m/m and 64.4 % m/m minimum. The amount of physical-mechanical contaminations that were identified in honey from 4 areas with the exemption of samples from Egypt apiaries poses no risk to consumers.
 Contribution to Policy Implication: This study recommends interventions among farmers and beekeepers on the safe use of pesticides, good hygienic handling, and the storage practices. It has contributed to the understanding of how the regulations outlining the use of insecticides is being implemented, and the current economic condition of studied farms. This calls on policymakers to rethink ways of engaging the beekeepers, and to have an ongoing discussion with beekeepers and concerned stakeholders about a model that could be used to enhance pesticides regulation in Tanzania.

Improved Sugar Recovery of Alkaline Pre-Treated Pineapple Leaf Fibres via Enzymatic Hydrolysis and Its Enzymatic Kinetics

The biofibre complex structure in pineapple leaf fibres (PALFs) can be disrupted using the alkaline pre-treatment method with sodium hydroxide (NaOH). Nonetheless, the pre-treated structures have an impact on the bioconversion of PALFs into sugar. Thus, the impact necessitates precise reaction conditions, which are required for the enzymatic hydrolysis of PALFs. In this study, the Box–Behnken design (BBD) was utilised to achieve maximum sugar yield from PALFs. The optimised enzymatic hydrolysis conditions were 229 µg/mL of cellulase, a reaction temperature of 45 °C, and a hydrolysis time of 69 h. Resultantly, an 84% increase in sugar yield was observed, from 17.26 mg/mL to 108.74 mg/mL after the optimisation process. Moreover, a significant influence (p = 0.0009) of the enzymatic hydrolysis on hydrolysis time and temperature was observed. Additionally, the kinetic study analysis of NaOH pre-treatment and the enzymatic hydrolysis process were investigated. The kinetics of enzyme concentrations on total reducing sugar (TRS) production using an insoluble substrate were investigated based on modified Michaelis–Menten and Chrastil models. The result of the models is in good agreement with the experimental data, as the PALF hydrolysis process was reasonably well predicted. This study provides valuable information for predicting the sugar yield of the PALF bioconversion.

Pre-sowing enrichment of Echinacea angustifolia seeds with macronutrients improved germination performance and early seedling growth via stimulating the metabolism of reserves

Seed enrichment with macronutrients such as N, K and P through nutrient seed-priming is a low-cost and low-risk technique to improve seed vigor and proper establishment of early seedlings. The objective of this study was to assess the potential of nutrient-enrichment of Echinacea angustifolia seeds, a high-valuable medicinal plant in pharmaceutical industry, with NK, KP or NKP through seed-priming with KNO3, KH2PO4 and a mixture of KNO3 and KH2PO4, respectively, on seed germination indices and early growth of seedlings, relative to non-enrichment treatments (non- and water-priming). The data showed that vigor of NK-, KP- or NKP-enriched seeds improved when compared with non-enriched seeds, while the highest seed vigor was manifested by NKP-enriched seeds. This finding was supported by higher final germination percentage, germination rate indices, coefficient uniformity of germination and seedling vigor index, and less mean germination time observed for macronutrient-enriched seeds, especially for NKP-enriched seeds. Other evidence to support enhanced vigor of macronutrient-enriched seeds was increased activity of total dehydrogenase (an indicator for accessing seed viability and vigor) in NK-, KP- and NKP-enriched seeds, with the highest activity in NKP-enriched seeds. In addition, the growth of early seedlings obtained from NK-, KP- and NKP-enriched seeds increased relative to that of the seedlings obtained from non-enriched seeds, with the highest early growth for the seedlings originating from NKP-enriched seeds. The activities of α-amylase and β-amylase were stimulated in NK-, KP- and NKP-enriched seeds, with the highest stimulation being observed in NKP-enriched seeds. This finding was consistent with the highest total reducing sugars and total soluble sugars in NKP-enriched seeds. Therefore, pre-sowing enrichment of the seeds with NKP can be suggested to improve seed vigor and vigorous establishment of early seedlings in nutrient-poor soils.

Lipid bioproduction through optimization of thermal diluted acid pretreatment on native grass using Yarrowia lipolytica

In the present study, thermal-dilute sulfuric acid pretreatment was performed on native grass (Cyperus distans) biomass for achieving optimized simple sugar recovery. Lipid bioproduction was performed using Yarrowia lipolytica from pretreated native grass biomass. Optimization of thermal diluted acid pretreatment on native grass biomass was investigated using one factor at a time (OFAT) method and response surface methodology. The maximum total reducing sugar (34.26 ± 1.55 g/L) in native grass hydrolysate was obtained at 163.8 °C, 1.57 % (v/v) of sulfuric acid concentration for 21 min. Minimization of formed inhibitors was performed using detoxification. About 11.64 ± 0.84 g/L of lipid was produced with 65.52 % (w/w) of lipid content after 96 h from detoxified native grass hydrolysate using Y. lipolytica in a 5 L fermentor. Result revealed that optimization of thermal diluted acid pretreatment on native grass biomass is an efficient method for lipid production using Y. lipolytica.

Additives Enhancing Enzymatic Hydrolysis of Wheat Straw to Obtain Fermentable Sugar.

In order to explore the effect of additives on enzymatic hydrolysis of lignocellulose biomass, the effect of two different additives, Triton X-100 (TX-100) and Bovine serum albumin (BSA), enzyme dosages, and additive concentrations on enzymatic hydrolysis to obtain fermentable sugar using cellulose extracted from wheat straw (WS) as the substrate was investigated in this study. An enzymatic hydrolysis kinetic model was used to successfully describe the enzymatic hydrolysis in a heterogeneous system. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to determine the effect of extraction and enzymatic hydrolysis on the composition and structure of the samples. The results showed that the total reducing sugar concentration of the raw was 1.535g/L at 120h, but that of the extracted cellulose (EC) increased to 5.087g/L at 120h, indicating that EC from WS is more conducive to enzymatic hydrolysis compared with the raw. The total reducing sugar concentration with the addition of the TX-100 was 6.737g/L at 120h, which was greater than that with the addition of the BSA (5.728g/L at 120h), indicating that the addition of two additives improved the enzymatic hydrolysis efficiency, especially TX-100. The kinetic studies showed that the initial enzymatic hydrolysis reaction rate (Km) of the EC was more than four times greater than that of the raw. The Km of the EC added with TX-100 and BSA were increased by 29.50% and 22.89% compared with that of the EC without the addition of additive. The addition of additives is an effective method for enhancing enzymatic hydrolysis efficiency and fermentable sugar production from lignocellulosic biomass.

Pilot-scale conversion of corn stover into lipids by the red yeast Rhodosporidium toruloides

Microbial lipid-based biorefinery has gained much attention because of its potential social and environmental benefits. While several studies were done on lipid production from lignocellulosic biomass at small scale, many processing details were not well-documented, and the suitability for scaling-up remained unclear. Here we report results of lipid production from corn stover (CS) by the red yeast Rhodosporidium toruloides CGMCC 2.1389 in a 1000-L bioreactor. The entire process included alkaline pretreatment, enzymatic hydrolysis, hydrolysates preparation, cell cultivation, and lipid recovery. It was found that the hydrolysates preparation step was heavily affected by the performance of its preceding steps. We achieved CS digestibility up to 90% and successfully obtained hydrolysates for lipid production at a yield of 0.17 g lipid per g total reducing sugar. Enzyme-assisted lipid recovery from the culture broth was also verified at a 50-L scale with a total lipid extraction rate of 74%. Overall, the conversion of CS into microbial lipids was fully verified at pilot-scale, and key issues were identified for further improvements in future studies.

Biogenic CuO and ZnO Nanoparticles as Nanofertilizers for Sustainable Growth of Amaranthus hybridus.

The biogenic synthesis of CuO and ZnO nanoparticles (NPs) was carried out by Stenotrophomonas maltophilia. The shape, size, and chemical identity of the CuO and ZnO NPs were determined using FTIR, XRD, SEM, EDX, and TEM analysis. The study aimed to investigate the effects of the CuO and ZnO NPs on Amaranthus hybridus seed germination and plant growth. Two different fertilizer application modes (hydroponics and foliar) were studied with varying concentrations of CuO (0.06 µM, 0.12 µM) and ZnO (0.12 µM, 0.24 µM) nanoparticles with water control and Hoagland’s media control. The hydroponic system of fertilizer application demonstrated better efficiency in terms of plant growth as compared to the foliar application. The agronomic traits, SPAD value, total reducing sugars, antioxidant activity, amount of copper, and zinc ions in root and shoot were analyzed for all experimental plants and found better with the nanoparticle application. The highlight of the study is the application of extremely low concentrations of CuO and ZnO nanoparticles, almost 70% lower than the copper and zinc salts in the Hoagland’s medium for improved plant growth. The use of lower concentrations of nanoparticles can prevent their accumulation in the environment and also lower the production cost. The high antioxidant concentration exhibited by the plants treated with CuO and ZnO nanoparticles ensures the enhanced plant’s resistance to infections and pests while promoting plant growth.

Estimation of degradation kinetics of bioactive compounds in several lingonberry jams as affected by different sweeteners and storage conditions.

Lingonberry fruits are considered to play an important role in nutrition, as they comprise a variety of health-promoting components. Because of lingonberries seasonal availability and also due to their rapid degradation, their stability during processing is a continuous challenge for the food industry. Lingonberries are ideal fruits in making jam due to their natural deep reddish color, but recently, increased demand for low-calorie jams with alternative sweeteners has gained special attention. In this line, the objective of this study was to monitor the changes in anthocyanins, vitamin C, total phenolics, total reducing sugars and antioxidant capacity of several lingonberry jams formulated with different sweeteners (sucrose, fructose, erythritol, brown sugar, coconut sugar, stevia, saccharin). Due to the fact that storage conditions are important factors for jam quality, the jams were stored for 180days at 4°C and 25°C (both under light and dark conditions). The rate constants (k) and the half time values (t1/2) of the degradation processes were determined and degradation kinetics was studied. For all analyzed conditions, first-order reaction kinetics was established for the degradation process of anthocyanins, whereas a second-order kinetic model described the degradation of the other compounds. Kinetic parameters showed that the stability of the studied compounds was highly influenced by the type of sweetener used in jam formulation. Total phenolics and antioxidants were best preserved in the presence of stevia, coconut sugar and fructose, whereas a destabilizing effect of erythritol on vitamin C and anthocyanins content during storage was observed. Among all the studied compounds, anthocyanins presented the fastest degradation, regardless storage conditions. The stability of studied compounds was higher at lower storage temperature (4°C), while increasing the temperature at 25°C and exposure to light determined higher rate of the degradation processes. The results provide useful information for understanding some bioactive compounds degradation in real foods, contributing to the development of new food products and providing information of commercial importance.