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Given crude oil prices and their environmental impacts, the use of sustainable renewable alternative energies such as biofuels is rapidly progressing in numerous countries. Among biofuels, bioethanol is a renewable and clean fuel that can be obtained from the fermentation of several raw agricultural materials, including date fruit. However, the low product yield, mainly due to the low-grade nutrient content, limits its use as a promising alternative biofuel. This current study investigated bioethanol production from date by-products in Saudi Arabia and examined the impact of calcium and nitrogen sources added at different concentrations (0 to 1 g/L) on the productivity and ethanol concentration using Saccharomyces cerevisiae. Yeast extracts and ammonium chloride (NH4Cl) were tested as nitrogen sources for bioethanol fermentation from date juice. Calcium chloride (CaCl2) and calcium carbonate (CaCO3) were evaluated as calcium sources for the same purpose mentioned above. The results showed that both calcium and nitrogen sources improved ethanol production efficiencies. The addition of calcium sources such as CaCl2 at 0.4 g/L resulted in maximum ethanol concentration (41.5 ± 0.85 g/L) and the highest productivity of 0.511 g/L/h. Thus, an increase of 31.3% compared to the control sample was acquired. Ammonium chloride was found to be the best nitrogen supplement among them. Indeed, supplementing the fermentation medium with 1 g/L NH4Cl gave an optimal ethanol concentration and productivity, reaching more than 65 g/L and 0.83 g/L/h, respectively. This is an increase of 106.6%. The functional group of ethanol (C2H5OH) for all the elaborated samples was confirmed by Fourier-transform infrared spectroscopy (FTIR) and NMR analyses. Moreover, the results confirmed the high quality and purity of the bioethanol products. Thus, the “Khodhari” date variety of low market value is a privileged substrate for industrial bioethanol production. For this reason, a proposed flow diagram of a designed plant for bioethanol industrialization is provided and detailed.

The increasing global population has led to an increase in food demand; consequently, aquaculture is one of the food production sectors that has offered opportunities to alleviate hunger, malnutrition, and poverty. However, the development of a sustainable aquaculture industry has been hindered by the limited availability of natural resources as well as its negative impact on the surrounding environment. Hence, there is an urgent need to search for better aquacultural production systems that, despite their high productivity and profitability, utilize fewer resources such as water, energy, land, and capital in conjunction with a negligible impact on the environment. Biofloc technology (BFT) is one of the most exciting and promising sustainable aquaculture systems; it takes into account the intensive culture of aquatic species, zero water exchange, and improved water quality as a result of beneficial microbial biomass activity, which, at the same time, can be utilized as a nutritious aquaculture feed, thus lowering the costs of production. Furthermore, BFT permits the installation of integrated multi-trophic aquaculture (IMTA) systems in which the wastes of one organism are utilized as feed by another organism, without a detrimental effect on co-cultured species. This review, therefore, highlights the basics of BFT, factors associated with BFT for the successful production of aquatic species, the significance of this food production system for the sustainable production of economically important aquatic species, its economic aspects, drawbacks, limitations, and recommended management aspects for sustainable aquaculture.

Fermentative production of optically pure lactic acid has roused interest among researchers in recent years due to its high potential for applications in a wide range of fields. More specifically, the sharp increase in manufacturing of biodegradable polylactic acid (PLA) materials, green alternatives to petroleum-derived plastics, has significantly increased the global interest in lactic acid production. However, higher production costs have hindered the large-scale application of PLA because of the high price of lactic acid. Therefore, reduction of lactic acid production cost through utilization of inexpensive substrates and improvement of lactic acid production and productivity has become an important goal. Various methods have been employed for enhanced lactic acid production, including several bioprocess techniques facilitated by wild-type and/or engineered microbes. In this review, we will discuss lactic acid producers with relation to their fermentation characteristics and metabolism. Inexpensive fermentative substrates, such as dairy products, food and agro-industrial wastes, glycerol, and algal biomass alternatives to costly pure sugars and food crops are introduced. The operational modes and fermentation methods that have been recently reported to improve lactic acid production in terms of concentrations, yields, and productivities are summarized and compared. High cell density fermentation through immobilization and cell-recycling techniques are also addressed. Finally, advances in recovery processes and concluding remarks on the future outlook of lactic acid production are presented.

Abstract Aim This study aims to use fermentation waste of ethanol production (solid and liquid) for riboflavin and recycling of bacterial biomass as biofertilizers to enhance the growth of some oily crop plants. Methods and Results Out of 10 yeast isolates from fresh milk, Clavispora lusitaniae ASU 33 (MN583181) was able to ferment different concentrations of glucose (2.5%, 5%, 7.5%, 10%, 15% and 20%) into ethanol with high efficiency at 10%. Among seven non-Lactobacillus bacterial isolates recovered from cheese samples, two bacterial isolates Bacillus subtlis-SR2 (MT002768) and Novosphingobium panipatense-SR3 (MT002778) were selected for their high riboflavin production. Different media (control medium, fermentation waste medium and a mixture of the fermentation waste medium and control medium [1:1]) were used for riboflavin production. These media were inoculated by a single or mixture of B. subtlis-SR2, N. panipatense-SR3. The addition of the waste medium of ethanol production to the control medium (1:1) had a stimulatory effect on riboflavin production whether inoculated with either a single strain or a mixture of B. subtlis-SR2 and N. panipatense-SR3. A mixture of fermentation waste and control media inoculated with N. panipatense produced a high riboflavin yield in comparison with other media. Inoculation of Zea mays and Ocimum basilicum plants with either the bacterial biomass waste of riboflavin production (B. subtlis or N. panipatense) or a mixture of B. subtlis and N. panipatense) shows a stimulatory effect on the plant growth in comparison with control (uninoculated plants). Conclusions These results demonstrate the possibility of minimizing the cost of riboflavin and biofertilizer manufacturing via interlinking ethanol and riboflavin with the biofertilizer production technology. Significance and Impact of Study This study outlines the methods of evaluating the strength of spent media by applying procedures developed in the vitamin production industries. Furthermore, bacterial biomass waste can act as an environmentally friendly alternative for agrochemicals.

The Eastern Mediterranean Region (EMR) is considered among the world’s most vulnerable to the dire impacts of climate change. This review paper aims at (1) characterizing climate change in countries of the EMR; (2) examining the potential effects of climate change on the nutritional and health status of the population; and (3) identifying the most vulnerable population groups. The paper explored several climate change indicators including daily temperatures, extreme temperature, daily precipitation, extreme precipitation (flooding, drought, storms, etc.), humidity, CO2 concentrations and sea surface temperature in EMR countries. Findings suggest that climate change will exert a significant adverse effect on water and food security and showed that the nutritional status of the population, which is already characterized by the triple burden of malnutrition, is likely to worsen via three main pathways mediated by climate change, namely, its impact on food security, care and health. Women, infants, children, those living in poor households and those experiencing displacement will be among the most vulnerable to the nutritional impacts of climate change. The paper concludes with a set of recommendations from the Initiative on Climate Action and Nutrition, which can support the region in tackling the critical nexus of climate change and nutrition.

The need for a shift in diet toward a more sustainable one has reached an urgency in certain regions, including Iran, due to more rapid climate change and a higher level of vulnerability. This study was undertaken to identify and summarize available data on changes required in the current Iranian diet to make it more sustainable and the extent to which current policies in the country have addressed such a shift. In this study, PubMed, Scopus, and Web of science, as well as Iranian scientific search engines, including Scientific Information Database and Magiran, were systematically searched from January 1990 to July 2021. A total of 11 studies and policy analyses were included in this study. Based on the findings, moving Iranian diet toward sustainability will require increase in consumption of dairy, fruits, vegetables, cereals, poultry, and legumes and decrease in consumption of bread, rice, pasta, red meat, eggs, fats, sugars, and sweets. There has been a great deal of effort and investment on policies and strategies to decrease the amount of sugar, salt, and fat (specifically trans-fatty acids) in the Iranian diet, which makes it more sustainable healthwise. Several policies and programs have been implemented to tackle non-communicable diseases (NCDs) by reducing access to unhealthy foods, which is in line with health dimension of a sustainable diet. However, there is almost no direct address to ecological aspect of sustainable diet in the food and nutrition policy documents in the ccountry. Development of an enabling environment to a sustainable diet will require policy and actions to improve public awareness, support study to provide evidence and identify possible alternatives, and plan and implement interventions/programs to promote and facilitate healthy and sustainable diets.

Coal combustion generates many gases and emissions which are harmful to public health and the environment. So, it is necessary to assess the health risks for the people living in the nearby cement plants that use coal as a fuel. In this article, a health risk assessment HRA was carried out concerning the air emissions from a cement plant in the heavy industry area located at Beni Suef governorate - Egypt. The article handles the assessment of the health risks for pollutants classified as non-carcinogenic i.e. sulfur dioxide - mercury and the health risks for pollutants classified as carcinogenic i.e. arsenic – chromium VI. An Air dispersion modeling program AERMOD is used to measure and evaluate long and short terms health impacts to expect the concentration of pollutants at the ground level within 30 km radius of the studied cement plant. The emissions measurements findings are used as input to the model in addition to some factors such as meteorology and surrounding terrain. Consequently, the program can implement simulations for the emissions concentration level of the mentioned pollutants and their effects on the population at Jazirat Abu Salih village, which is 10 km far from the studied cement plant. The results for mentioned pollutants concentrations levels matched with acceptance and safe levels of ambient air quality standards. In addition, the increment lifetime cancer risk ILCR by inhalation was calculated for arsenic and chromium and all results conformed with the safe and accepted limits.

The present study was aimed to evaluate the suitability of agro-wastes and crude vegetable oils for the cost-effective production of poly-β-hydroxybutyrate (PHB), to evaluate growth kinetics and PHB production in Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 with these carbon substrates and to study the biodegradation of PHB accumulated by these cultures. Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 accumulates higher amounts of PHB corn (79.90% of dry cell mass) and rice straw (66.22% of dry cell mass) medium respectively. The kinetic model suggests that the Pseudomonas sp. RZS1 follows the Monod model more closely than A. faecalis RZS4. Both the cultures degrade their PHB extract under the influence of PHB depolymerase. Corn waste and rice straw appear as the best and cost-effective substrates for the sustainable production of PHB from Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1. The biopolymer accumulated by these organisms is biodegradable in nature. The agro-wastes and crude vegetable oils are good and low-cost sources of nutrients for the growth and production of PHB and other metabolites. Their use would lower the production cost of PHB and the low-cost production will reduce the sailing price of PHB-based products. This would promote the large-scale commercialization and popularization of PHB as an ecofriendly bioplastic/biopolymer.