This is a working overview of amino acids, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-04-09 and is reviewed periodically as new material appears.
Collagen peptides are short chains of amino acids produced by hydrolyzing collagen from animal connective tissues. The parent protein occurs in skin, bone, tendons, and cartilage, where it provides tensile strength. Hydrolysis breaks native triple-helical structures into smaller fragments, improving solubility in water. The resulting mixture consists mainly of glycine, proline, hydroxyproline, and other residues. Commercial ingredients are often described by average molecular weight rather than a single defined molecule.
Industrial production typically begins with raw materials such as bovine hide, porcine skin, fish skin, or eggshell membrane. A pretreatment step removes fat and non-collagenous proteins, after which enzymes or acid/alkali conditions cleave peptide bonds. Manufacturers then purify, concentrate, and dry the hydrolysate into a powder. The degree of hydrolysis influences peptide length, solubility, and taste. Because source and process vary, two collagen peptide powders can differ in amino acid profile and molecular weight distribution.
Common sources for collagen peptide production include bovine hide, porcine skin, fish skin, and poultry cartilage. The raw material is first cleaned and then treated with enzymes such as pepsin or microbial proteases under controlled conditions. Hydrolysis time, temperature, and enzyme concentration influence the final peptide size distribution. After hydrolysis, the mixture undergoes filtration, purification, and drying to yield a powder. The amino acid composition is notable for high levels of glycine, proline, and hydroxyproline, which are characteristic of collagen.
The functional properties of collagen peptides depend on their molecular weight profile and amino acid sequence. They are highly soluble in water and produce low-viscosity solutions even at relatively high concentrations. Some peptides exhibit surface activity, which allows them to act as emulsifiers or foaming agents in food systems. The absence of a rigid triple-helical structure distinguishes them from gelatin, which can form gels upon cooling. Chromatographic separation and mass analysis are used to characterize the peptide mixture.
Collagen peptides are short chains of amino acids derived from collagen, a structural protein found in connective tissues such as skin, bone, and cartilage. The production process involves breaking native collagen into smaller fragments through hydrolysis, which cleaves peptide bonds. Unlike intact collagen, these peptides dissolve in water and do not form a triple helix. Commercial preparations typically contain peptides with molecular weights ranging from about 2,000 to 20,000 daltons. The term collagen peptide is often used interchangeably with hydrolyzed collagen or collagen hydrolysate.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | Hydrolyzed collagen, collagen hydrolysate, gelatin hydrolysate | Peptide and hydrolysate are often used interchangeably. |
| Typical sources | Bovine hide, porcine skin, fish skin, eggshell membrane | Source affects amino acid profile and labeling. |
| Appearance | White to off-white powder | Color can vary slightly with raw material and processing. |
| Solubility class | Water-soluble | Dissolves in cold or warm water better than native collagen. |
| Average molecular weight | Typically 1–10 kDa | Values depend on hydrolysis conditions and measurement method. |
Rhodesia, officially the Republic of Rhodesia from 1970 onwards, was an unrecognised state in Southern Africa that existed from 1965 to 1979. Rhodesia was the de facto successor to the self-governing colony of Southern Rhodesia following its unilateral declaration of independence (UDI) from the United Kingdom in 1965. Throughout this fourteen-year period, Rhodesia faced internal conflict and political unrest. Following the Lancaster House Agreement in 1979 and general elections held under a universal suffrage in 1980, the territory finally gained de jure independence and international recognition as the Republic of Zimbabwe. The rapid decolonisation of Africa in the late 1950s and early 1960s alarmed a significant proportion of Southern Rhodesia's white population. In an effort to delay the transition to black majority rule, the white Southern Rhodesian cabinet issued a unilateral declaration of independence (UDI) from the United Kingdom on 11 November 1965. The new nation, renamed Rhodesia, initially sought recognition as an autonomous realm within the Commonwealth of Nations, but reconstituted itself as a republic in 1970. Following the UDI, the United Nations Security Council passed resolution 216 which called upon all states to deny recognition and assistance to Rhodesia. Two far-left African nationalist parties, the Zimbabwe African People's Union (ZAPU) and Zimbabwe African National Union (ZANU), launched an armed insurgency against the government after the UDI, sparking the Rhodesian Bush War.
For example, there is the Pomodorino del Piennolo del Vesuvio, the "hanging tomato of Vesuvius", and the well-known and highly prized San Marzano tomato grown in that region, with a European protected designation of origin certification.
Most researchers define Avialae as branch-based clade, though definitions vary. Many authors have used a definition similar to "all theropods closer to birds than to Deinonychus", with Troodon being sometimes added as a second external specifier in case it is closer to birds than to Deinonychus. Avialae is also occasionally defined as an apomorphy-based clade (that is, one based on physical characteristics). Jacques Gauthier, who named Avialae in 1986, re-defined it in 2001 as all dinosaurs that possessed feathered wings used in flapping flight, and the birds that descended from them. Despite being currently one of the most widely used, the crown-group definition of Aves has been criticised by some researchers. Lee and Spencer (1997) argued that, contrary to what Gauthier defended, this definition would not increase the stability of the clade and the exact content of Aves will always be uncertain because any defined clade (either crown or not) will have few synapomorphies distinguishing it from its closest relatives. Their alternative definition is synonymous with Avifilopluma.
Because common law judges historically gave inadequate remedies for workers who were dismissed, and let employers dictate the terms of dismissal by contract, the Fair Work Act 2009 section 382 contains the right to be "protected from unfair dismissal", if the person is an employee, and under section 383 they have been working for at least 6 months, or one year for an employee of an employer with under 15 staff. Small businesses may have a defence if they comply with the Small Business Fair Dismissal Code. In addition, employees must be covered by an award or enterprise agreement, and have an income below $167,500 in July 2023 (the "high income threshold"). Another exception is that "casual" employees have no rights unless they have a "reasonable expectation of continuing employment by the employer on a regular and systematic basis". In Ponce v DJT Staff Management Services a traffic controller employed through a labour hire firm, and classed as "casual", had unpredictable work shifts and some breaks in work, but was still held to have had work on a regular and systematic basis. Unlike in most high income countries, the Fair Work Act 2009 fails to treat expiry of fixed-term contracts as a dismissal that must be fair. The meaning of dismissal includes termination, or being forced to resign by the employer's conduct, or demotion with a significant reduction of pay or duties.
Sources: en.wikipedia.org
The original Counter-Strike has been played in competitive tournaments since 2000, with the first major event taking place at the Cyberathlete Professional League (CPL) Winter Championship in 2001. The CPL announced a transition from Quake III Arena to Counter-Strike for the Winter Championship. Prior to this, the 2000 Babbage's event featured a Counter-Strike competition sponsored by Kärna, the parent company of Razer, offering a $15,000 prize pool. However, Kärna experienced financial difficulties, leading to delays in prize payouts. On March 14, 2001, the CPL issued a statement confirming that alternative arrangements would be made if the payments were not received by April 2, 2001.
==== Precipitation amount effect ==== In contrast to temperature control at high latitudes, the isotopic composition of precipitation in the tropics is mainly influenced by rainfall amount (negative correlation). This "amount effect" is also observed for summer precipitation in the subtropics. Willi Dansgaard, who first proposed the term "amount effect", suggested several possible reasons for the correlation: (1) As cooling and condensation progress, the rainfall isotopic composition reflects an integrated isotopic depletion by the Rayleigh process; (2) A small amount of rainfall is more likely to be influenced by evaporation and exchange with surrounding moisture, which tend to make it more isotopically enriched. At low latitudes, the amount effect for δ18O is around −1.6‰/100mm precipitation increase at island stations, and −2.0‰/100mm at continental stations. It was also noted that the amount effect was most pronounced when comparing isotopic composition of monthly precipitation at different places in the tropics. The amount effect is also expected for HIC, but there are not as many calibration studies. Across southeast Asia, the δD sensitivity to monthly precipitation amount varies between −15 and −25‰/100mm depending on location. In temperate regions, the isotopic composition of precipitation is dominated by rainfall amount in summer, but more controlled by temperature in the winter. The amount effect may also be complicated by changes in regional moisture sources.
Glycolysis – The first stage is known as glycolysis, which produces 2 ATP molecules, 2 reduced molecules of nicotinamide adenine dinucleotide (NADH) and 2 pyruvate molecules that move on to the next stage – the Krebs cycle. Glycolysis takes place in the cytoplasm of normal body cells, or the sarcoplasm of muscle cells. The Krebs cycle – This is the second stage, and the products of this stage of the aerobic system are a net production of one ATP, one carbon dioxide molecule, three reduced NAD+ molecules, and one reduced flavin adenine dinucleotide (FAD) molecule. (The molecules of NAD+ and FAD mentioned here are electron carriers, and if they are reduced, they have had one or two H+ ions and two electrons added to them.) The metabolites are for each turn of the Krebs cycle. The Krebs cycle turns twice for each six-carbon molecule of glucose that passes through the aerobic system – as two three-carbon pyruvate molecules enter the Krebs cycle. Before pyruvate enters the Krebs cycle it must be converted to acetyl coenzyme A. During this link reaction, for each molecule of pyruvate converted to acetyl coenzyme A, a NAD+ is also reduced. This stage of the aerobic system takes place in the matrix of the cells' mitochondria. Oxidative phosphorylation – The last stage of the aerobic system produces the largest yield of ATP – a total of 34 ATP molecules. It is called oxidative phosphorylation because oxygen is the final acceptor of electrons and hydrogen ions (hence oxidative) and an extra phosphate is added to ADP to form ATP (hence phosphorylation).
In the back of the chamber, there is packing around the piston or a doughnut-shaped seal with a toroid-shaped sphincter-like spring inside compressing the seal around the piston. This holds the fluid pressure when the piston slides in and out and makes the pump leak-tight. The packing or seals can wear out after prolonged use and can be replaced. The metering rate can be adjusted by varying the strokelength by which the piston moves back and forth or varying the speed of the piston motion. A single-piston pump delivers liquid to the outlet only during the discharge stroke. If the piston's suction and discharge strokes occur at the same speed and liquid is metered out half the time the pump is working, then the overall metering rate averaged over time equals half the average flow rate during the discharge stroke. Some single-piston pumps may have a constant slow piston motion for discharge and a quick retract motion for refilling the pump head. In such cases, the overall metering rate is practically equal to the pumping rate during the discharge stroke.
In Iran, dill is known as 'shevid' and sometimes, is used with rice and called 'shevid-polo'. It also is used in Iranian 'aash' recipes, and similarly, is called sheved in Persian. In India, dill is known as 'Sholpa' in Bengali, shepu (शेपू) in Marathi, sheppi (शेप्पी) in Konkani, savaa in Hindi, or soa in Punjabi. In Telugu, it is called 'Soa-kura' (herb greens). It also is called sabbasige soppu (ಸಬ್ಬಸಿಗೆ ಸೊಪ್ಪು) in Kannada. In Tamil it is known as sada kuppi (சதகுப்பி). In Malayalam, it is ചതകുപ്പ (chathakuppa) or ശതകുപ്പ (sathakuppa). In Sanskrit, this herb is called shatapushpa. In Gujarati, it is known as suva (સૂવા). In India, dill is prepared in the manner of yellow 'moong dal', as a main-course dish. It is considered to have very good antiflatulent properties, so it is used as 'mukhwas', or an after-meal digestive. Traditionally, it is given to mothers immediately after childbirth. In the state of Uttar Pradesh in India, a small amount of fresh dill is cooked along with cut potatoes and fresh fenugreek leaves (Hindi आलू-मेथी-सोया). In Manipur, dill, locally known as pakhon, is an essential ingredient of chagem pomba – a traditional Manipuri dish made with fermented soybean and rice. In Laos and parts of northern Thailand, dill is known in English as Lao coriander (Lao: ຜັກຊີ or Thai: ผักชีลาว), and served as a side with salad yum or papaya salad. In the Lao language, it is called 'phak see', and in Thai, it is known as 'phak chee Lao'.
Sources: en.wikipedia.org
They are derived from collagen-rich animal tissues, commonly bovine hide, porcine skin, fish skin, or eggshell membrane. Processing removes non-collagen proteins and breaks the collagen into smaller water-soluble fragments. The final ingredient is a mixture, not a single peptide.
Native collagen has a triple-helical structure and is largely insoluble in cold water. Hydrolysis disrupts that structure and shortens the chains, producing peptides that dissolve more readily. The two materials also differ in molecular weight and functional behavior in foods.
They are not considered complete proteins because they are low in or lack certain essential amino acids, including tryptophan. They can still contribute amino acids when eaten with other protein sources. Labels usually list protein content rather than a complete amino acid score.
Gelatin is a partially hydrolyzed form of collagen that retains the ability to form gels in water. Collagen peptides undergo more extensive hydrolysis, resulting in shorter chains that dissolve in cold water without gelling. The two products differ in molecular weight distribution and functional behavior.